Proceedings of the 27th annual meeting of the Società Italiana di Neurochirurgia, Rome, 16--18 November 1978. Abstracts.

ACTA NEUROCHIRURGICA

Acta Neurochirurgica 48, 121--148 (1979)

9 by Springer-Verlag 1979

Proceedings of the 27th Annual Meeting of the Societ~t Italiana di Neurochirurgia, Rome, 16-18 November 1978 Compiled by

I. P a p o * I. A n a e s t h e s i a and Intensive Care in N e u r o s u r g e r y

A. Puig, Carrillo, P., Mediero, J. M., Chito, P. F. (Neuroanaesthesia, Intensive Care Service, C. Ramdn y Cajal, Madrid): Sodium Nitroprusside in Cerebral Vascular Malformations. Sodium nitropruside is the drug we use intravenously to produce arterial hypotension by direct dilatation of the vessels. We have carried out several investigations on 90 patients of both sexes, aged from 23 to 65 years. The anaesthesia technique used in our Department is based on Neuroleptoanalgesia II and controlled ventilation to keep the PaO 2 sufficiently high and the PaCO~ between 25 and 30 mmHg, reducing in this way the cerebral blood flow and the intracranial pressure. ECG, pulse rate, plethismograms, arterial pressure, CVP, and ICP are monitorized as a general rule. Gasometries are performed during the pre-, per-, and postoperative stages. Measurement of the arterial pressure is carried out through radial or dorsalis pedis cannulas. Perfusion of SNP should be by intravenous catheter, preferably in an arm. The perfusion system is in fact an automatic bomb. Once the patient has been anaesthetized and all the constants steadied, we carry out a drug test. The total dose varies between 0.6 and 6 ~tgs/kg/min being in general terms 0.5-1.5 ~tgs/kg/min. These values depend on the cardiocirculatory condition and possible previous hypotensive medication, which reduces the dose. If 10 minutes later, we are not getting satisfactory result after a correct dosage, we stop the drug and try a new technique. As a general rule, in all our cases it has been quite enough to reduce the mean arterial pressure to 40-50 mm Hg in order to atta& and correct the vascular defect successfully. Hypotension times have varied between 6 and 130 minutes. The cerebral perfusion has been sufficient in spite of having a head elevation around 15 20% * Prof. Dr. I. Papo, Ospedale Generale Regionale, 1-60100 Ancona, Italy.

0001-6268179100481012115 05.60

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I. Papo:

Our cases have had good recovery from anaesthesia with a satisfactory neurological state. We have tried to ensure that the arterial pressure when leaving the surgical area is similar to the preoperative one. In all our controlled hypotension casualties with sodium nitroprusside, we have not met with tachyphylaxis or with thiocyanate poisoning. The explanation for this can be that we do not use such high doses as other authors, because we combine sodium nitroprusside with neuroleptanalgesia and controlled ventilation. In some patients we have also used halothane 0.5-1% to reduce the SNP dose still further. A . P u i g , J a r a b a , J., G a F a l c e s , C., H e r r e r o , C. ( N e u r o a n a e s t h e s i a , I n t e n s i v e C a r e S e r v i c e , C. R a m 6 n y C a j a l , M a d r i d ) : Influence of

Sodium Nitroprusside in Cerebral Dynamics. We have studied the dynamic changes from sodium nitroprusside in patients who were surgically treated for cerebral vascular malformations. The previously described methodology brought the following results. When mean arterial pressure is decreasing there is a simultaneous increase of the ICP. In those with the dura closed ICP may reach values over 40%. At the same time the Perfusion Pressure may decrease down to 50%. In spite of these changes the SNP is able to maintain a sufficient cerebral blood flow due to its dilatation action, produced without myocardium depression or diminution of the cardiac output. We do not know whether such increases of the ICP are due to an increase of the cerebral blood flow by direct vessel dilatation or to a simple auto-regulation response to the arterial hypotension. We never found any signs of cerebral hypoxia, as the demand for oxygen falls in anaesthetized patients. The results agree with those of Turner and McDowall, who found some increase in the ICP in the early stages of hypotension. This disappears at lower MAP levels or when the SPN perfusion is reduced. At the end of the administration the arterial pressure comes back gradually to basal values while the ICP may remain slightly decreased. Looking at these investigations, we can establish, that the SNP increases the CBF and consequently the ICP only in cases of moderate arterial hypotension with normocapnia, and it could be of certain importance in patients having an intact dura mater. We prevent possible troubles by hyperventilating the surgical patient with IPP, controlled by arterial gasometries, in order to keep the PO~ increased and the PCO.2 between 25 and 30 mm Hg, reducing in this way the CBF. On the other hand, the unquestionable benefits of NLA, which decrease ICP per se, enhance the already described effects, and the final result is a minimum dose of SNP with no risks of intoxication by thiocyanate, offering a surgical field under the best conditions. As complementary techniques, we find of special interest those recommended by McDowall in order to avoid ICP increases in normocapnic patients and those with the dura closed. 1. When SNP is used the arterial pressure should fall as quickly as possible to a level below 70 m m H g in order to avoid cerebral congestion and increases of ICP. 2. Infusion speed should be slowly reduced at the end of the hypotensive period in order to avoid an increase in arterial pressure before the alterated cerebral autoregulation mechanisms recover.

Proceedings of the 27th Annual Meeting

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Da Plan, R., Pasqualin, A., Vivenza, C., Scienza, R., Malesani, G. C. (Dipartimento di Neuroehirurgia and II Servizio di Anestesia e Rianimazione dell'Ospedale Civile di Verona): Neurosurgical Considerations About Sodium Nitroprusside-Induced Deep Controlled Hypotension. By deep hypotension, we mean hypotensive technique with blood pressure values below 60 mm Hg of systolic arterial pressure. Ninety-three patients with intracranial arterial aneurysms and 15 patients with intracranial AV malformations were operated on with this technique in our Department. The evaluation of the results obtained with the deep hypotensive technique is discussed by comparison with a similar group of patients operated on under normal pressure. Deep hypotension is undoubtedly the only effective procedure in the control of haemorrhage during surgery, especially in cases of aneurysmal rupture. The length of deep hypotension in single patients averaged between 30 and 60 minutes; in a few cases, periods of 2 or 3 hours were reached, especially when dealing with AV malformations. The advantages of this technique were obvious: 1. In the control of haemorrhage from aneurysmai rupture with no consequent need to close the afferent vessels. 2. In the use of bipolar coagulation for the reduction in size of large necks, owing to the marked decrease in intraaneurysmal pressure. 3. In the removal of huge AV malformations and in critical areas of the brain. Provided classical contraindications are observed, Sodium Nitroprusside-induced deep controlled hypotension has been shown to be an easily performed, low-risk procedure. No death or postoperative disturbances were shown to be clearly related to deep hypotension per se. Nevertheless, attention has to be paid to the use of deep hypotension in early surgery for intracranial aneurysms (i.e., before the 14th day after subarachnoid haemorrhage), due to the possible association of deep hypotension with vascular spasm and the consequent ischaemic complications.

Guariento, V., Battaglia, C., Brigadeci, G., Zappala', V., Baietta, S., Scienza, R., Da Plan, R., Malesani, G. C. (II Servizio di Anestesia e Rianimazione e Dipartimento di Neurochirurgia di Verona): Anesthesiological, Clinical, and Bio-Humoral Aspects of Deep Hypotension Induced by Sodium Nitroprusslde for the Surgical Treatment of Intracranial Aneurysms and Angiomas. Experience Derived from 108 Cases. From February 1976 to August 1978 in the Department of Neurosurgery of Verona 93 intracranial aneurysms and 15 intracranial arterio-venous malformations were surgically treated under deep hypotension induced by sodium nitroprusside. Cerebral, cardiocirculatory, renal, and metabolic parameters were generally satisfactory, thus confirming the easy use of the drug and the validity and safeness of the method, with pressure values (30 mm Hg) and durations (two to three hours) which had not been leasable until recently.

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I. Papo:

* U r c i u o l i , R., ** R e y n e r i , C., ** Tosetti, L., *** L i b o n i , W., * Lo Russo, G., * G i u n t e l l i , V., ':" Frego, L. (* I s t i t u t o di N e u r o c h i r u r g i a - - D i r e t t o r e : V. A. F a s a n o , ** F a r m a c i a , O s p e d a l e M a g g i o r e San G. B a t t i s t a d e l i a citt~t di T o r i n o , *":'* S e r v i z i o N e u r o r a d i o l o g i a C l i n i c a N e u r o l o g i c a I I , U n i v e r s i t ~ degli S t u d i di T o r i n o ) : Con-

trolled Hypotension With Intravenous Nitroglycerine surgery.

in Neuro-

Intravenous Nitroglycerine has been used intraoperatively to produce controlled hypotension in 30 neurosurgical cases during elective neurosurgical procedures for aneurysm, arterio-venous malformation, cerebral turnouts. Its pharmacological aspects and ability to produce a rapid fall in blood pressure~ without causing harmful effects, impairment of cerebral autoregulation, or change of intracranial pressure, are compared with other agents in use today (trimethaphan-Sodium Nitroprusside). Controlled hypotension was induced with the prepared solution of nitroglycerine via an infusion pump in order to achieve a mean arterial blood pressure from 80 torr to not lower than 50 torr. All patients during hypotension were monitored by continuous blood pressure and pulse rate records, EEG spectral analysis, intracranial pressure, and cerebral blood-flow; respiration was controlled artificially to correct paCO2 to 30 torr. EEG spectral analysis was carried out according to Fourier's traditional transformation. Intracranial pressure was recorded by "Hellige Epidural electromanometer", and cerebral blood flow determination was controlled by Doppler external probe on the common carotid, ophthalmic, temporal, and brachial arteries. Some cases underwent a selective carotid-cerebral angiography at 50 tort levels of blood pressure. The characteristics of nitroglycerine preparation, clinical evaluation, and results are reported and discussed. D i G i u g n o , G., Izzi, A., Rosa, G. ( I n s t i t u t e of N e u r o s u r g e r y - - H e a d : B. G u i d e t t i , U n i v e r s i t y o f R o m e , I t a l y ) : General Anaesthesia

in Paediatric Neurosurgery. The peculiarity of the problems of paediatric general anaesthesia comes essentially from the particular physiopathologicaI characteristics of the child. The small respiratory volume and the small calibres of the gas lines contrast with the significant oxygen need. Tracheal intubation, which is essential in all cases, increases the respiratory resistance. This involves tiring of the weak respiratory musculature of the small child on spontaneous respiration, and in cases on controlled ventilation the necessity of applying high insufflation pressures. The need to provide small volumes with high frequency and high pressure requires special care in the reduction of the dead space of the respirator and the circuits. Small blood volume (8% of the body weight) makes the child very sensitive to haemorrhage. The precariousness of all the homeostatic regulation systems and of the nervous vegetative system can cause small alterations to endanger cardiovascular, respiratory, thermal, hydro-electrolytic and acid-base balances. As a matter of *'act, the relative importance of the volume of the extracellular liquids, the small capacity of the kidney, and the superior metabolic rate make the child less autonomous, and more liable to dehydratation, vascular collapse, and metabolic acidosis.


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Neurosurgery gives the anaesthesist specific problems that are generally more difficult to solve in the child: the control of intracranial volume and pressure, control of haemorrhage, position on the operating table. The first problem is solved by wise administration of osmotic diuretics, by CSF drainage and, above all, by moderate hyperventilation set so that the PaCO2 remains between 30 and 35 mm Hg. The control of haemorrhage mainly depends on the local infiltration of epinephrine (1:400,000) so as to avoid considerable bleeding from skin and muscle and on the postural drainage associated with moderate arterial hypotension, usually obtained without ganglioplegics to which, by the way, children show resistance. Many operations require the lateral, prone or sitting position. In the first two cases the main care will be the thorax abdomen freedom, necessary for a correct development of the gaseous exchanges and of the venous return. The sitting position in the operations on the posterior fossa cranica gives the best solution to the above mentioned problems but exposes the patient to the risk of cerebral ischemia and air embolism. It is essential so as to avoid the first one, to have a good possibility of control of the volemia and on the hypotension effects of the anaesthesia, which, therefore, must be quite manageable. To avoid the second risk an absolute control of the child's respiration is essential and the application of a light positive expiratory pressure can be very useful. Our series comprehends 858 operations of pediatric neurosurgery (Table i and 2) over the last ten years: this presumes a continuous evolution of the techniques that were being used. At present our behaviour can be thus summarized: We do not attach essential importance to the premedication which, if given, provides atropination and, in the children above one year of age, sedation with hydroxizine or diazepam with dosages that do not expose to the risk of preoperatory hypoventilation. We are using always more scarcely, even in the smaller children, the induction with volatile anaesthetics, generally preferring the endovenous administration of small doses of thiopental. The induction under mask is restrained to the rare cases in which the first attempts of vein injection fail. The use of the myorelaxing drug for the intubation is restrained to the children older than three years of age. The tracheal intubation is always performed with sondes of reinforced latex, head setted for the bigger children. Their placement requires particular care in all cases and can create a few problems in new-born babies and in the prone position. The techniques for the preservation of the anaesthesia can depend in part, on the type of operation performed but, in practice we are giving an always greater space to neurolepto-anaesthesia to the detriment of volatile agents. Their use is limited to the cases in which a significant hypotension is required and always in the last stages of the operation. A careful dosage of neuroleptoanaesthesia drugs scarcely exposes the patient to the risk of postoperative breath insufficiency and allows the best operative conditions together with a quiet postoperative course. We recommend in all cases the use of automatic lungs ventilation and a mixture of 50~ protoxide in oxygen. The control of vital parameters includes the oscillotonometric estimation of the A.P., the spirometric, ECGraphic, and thermometric monitoring, the auscultation of the cardiac action placing a phonendoscope over the precordial or interscapular region.

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I. Papo: Table 1. Distribution of Cases According to the Type of Lesion Non neoplastic hydrocephalus Subtentorial expanding lesions Supratentorial expanding lesions Encephalocele and myelomeningocele Craniostenosis Epilepsy-ECoG-hemispherectomy Other lesions

244 102 134 26 61 13 278

Total

858

Table 2. Cases Distribution According to the Age Age:

years

0-i

1-2

2-3

3-4

4-5

5-6

6-14

No.

cases

278

74

68

55

55

36

292

Years Years

0-2 0-6

cases 352 cases 566

* Zattoni, J., ** Rivano, C., * Siani, C., * Spina, G. (* Anaesthesia and Intensive Care Institute; '::~ NeurosurgicaI Institute, University of Genoa, Italy): Induction of Anaesthesia With an Intravenous Bolus of Althesin-Effects on ICP and Some Related Functions (AP, VP, EEG, aPCO.,_-apH-aPO,_,). Eight conscious patients on spontaneous respiration were given 0.5 mg atropine sulphate intramuscularly, and 30--40 minutes later, 40-50 (45.5 + 4.33 average) ~tl/kg of Althesin were injected to induce anaesthesia. Patients were admitted for cryptogenie, traumatic, or tumoural neurological disorders. Continuous and simultaneous recordings were made for intracranial pressure (ICP), systemic arterial pressure (AP), central venous pressure (VP), and electroencephalogram (EEG). Programmed evaluations were followed for aPCO2, apH, aPO 2, and pain reactivity. Spontaneous respiration was maintained during the whole session. ICP, AP, and VP were measured at their mean values. Data come from ten I.-V. injections of Althesin. ICP and AP decreased in all cases, while VP fell in half of them. Mean global ICP, AP, and VP drops were 6.82 + 3.91 (P < 0.05), 20.18 + 9.30, and 1.21 + 0.24 mm Hg. The maximum decrease of ICP (3.5-17 mm Hg) occurred three minutes after the injection, and was positively related (P < 0.05) to its basal value. AP never fell below 60 mm Hg. In five cases the EEG showed a dominant delta-wave pattern and in the other five typical burst-suppressions. During these phases, clinical pain reactivity was suppressed or greatly reduced. Spontaneous or evoked clonic movements were seen in some cases. Generally, aPCO,, increased by 1-5 mm Hg; in all cases aPO._, fell by 3-12 mm Hg. Apnoea for 20 seconds followed in three cases, and jaw relaxation in four. The recovery of ICP began within the second and fourth minutes after the injections. Consciousness was regained after 7-15 minutes. The basal values of ICP and AP were reached 12-22 and 6-22 minutes after the injections. No dangerous rebound was recorded.


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* Zattoni, J., ** Perria, C., * Siani, C., * Piva, R., * Patrone, S. (* Anaesthesia and Intensive Care Institute; ** Neurosurgical Institute, University of Genoa, Italy): Althesin Intravenous Infusion to Induce and Maintain Anaesthesia, Effects on ICP and Some Related Functions (AP, VP, EEG, aPCO2-apH-aP02). Nine conscious patients on spontaneous respiration were given 0.5 mg intramuscular atropine sulphate; 30-60 minutes later, infusions of Althesin began at speeds of 0.25, 0.35, and 0.60 ml/kg/h, and were adjusted at about 0.4 ml/kg/h after 7-10 minutes. Patients had cryptogenic, traumatic, or tumoural neurological disorders. During the whole session, intracranial pressure (ICP), systemic arterial pressure (AP), central venous pressure (VP), and the electroencephalogram (EEG) were continuously and simultaneously recorded. A programmed evaluation was followed for apCO2, apH, apO2, and clinical pain reactivity. ICP, AP, and VP were measured at their mean values. Data come from twelve intravenous Althesin infusions. ICP fell in twelve, AP in ten, and VP in six cases. Global mean ICP, AP, and VP drops were 3.88 _+ 1.22 (P < 0.05), 20.76 + 17.44 (P < 0.05), and 0.90 + 1.50 (P < 0.20) m m H g respectively. The decrease of the ICP began after 2-8 minutes of infusion and it did not differ in two cases with unchanged or increased AP. No relation was found between the drop of ICP and its basal value. In only one case did AP fall below 60 mm Hg. All infusions induced an EEG delta-wave pattern; in nine of them typical burst suppressions followed. Increases in apCO 2 were 0.6-5 mm Hg in nine cases; apO2 generally fell by 3-13.3 mm Hg. In one case the respiratory depression was associated with increase of ICP above the basal value. Clinical pain reactivity was suppressed or greatly reduced. In some cases there occurred spontaneous and evoked clonic movements. The recorded functions recovered after discontinuation of infusion. ICP and AP began to recover within 1-9 and 3-5 minutes respectively, and reached basal values after the following 5-8 minutes without dangerous rebounds. Consciousness recovered within 9-25 minutes.

Zattoni, J. (Anaesthesia and Intensive Care Institute, University of Genoa, Italy): Sequence of ICP, AP, VP, and EEG Changes After Intravenous Injection of Althesin. Under the same experimental conditions as reported in another communication, simultaneous and continuous recording of intracranial pressure (ICP), systemic arterial pressure (AP), central venous pressure (VP) and electroencephalogram (EEG) allowed us to observe the starting times of the effects induced by the intravenous injection of 40-50 (42.5 _+ 4.33 average) bd/kg of Althesin. Delays were measured from the beginning of the intravenous injection, and are here indicated in seconds. Data (mean + ES) concern eleven intravenous injections. 31.16 + 1.76 increased amplitude of high frequency waves and appearance of theta waves in EEG 37.35 + 3.13 EEG slowing due to diffuse delta waves 37.62 + 2.80 drop in the ICP 44.58 + 3.65 drop in the AP 56.52 + 2.81 drop in the VP (only in six injections) 62.70 + 4.14 apnoea (only in three injections) 74.01 + 8.51 appearance of burst suppression in EEG (only in five injections)

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I. Papo:

The beginning of the ICP drop preceded that of the AP ( P ~ 0 . 0 5 ) and of the VP (P < 0.05); and it was associated with either an increase or a decrease of apCO.,. Therefore, ICP behaviour cannot be attributed to AP, VP, or apCO2. The beginning of the ICP drop is almost simultaneous with the EEG slowing (P < 0.001). This is in agreement with the hypothesis (McDowall et al. 1972, Pickerodt et aI. 1972) that the ICP change is due to a brain metabolic depression inducing a physiological reduction of the cerebral blood flow.

Zanini, F., Verlato, R., * Benedetti, A., * Rubini, L., * Alexandre, A. (II Servizio di Anestesia e Rianimazione O.C. Vicenza, * Divisione di Neuro&irurgia O.C. Vicenza): Reflex Analgesia and Controlled

Hypotension During NeurosurgicaI Procedures. There is abundant evidence of the value of controlled arterial hypotension in the surgical treatment of intracranial aneurysms. But deep hypotension may not be used in patients who are old, or who suffer from hypertension or angiosclerosis. Even mild hypotension in these patients may be dangerous, and may interfere with the pharmacokinetics of anaesthetic drugs. In order to obtain a safer neurosurgical approach we employed an anaesthesiological procedure based on "reflex analgesia" by acupuncture, which affords exclusion or marked reduction of analgesic drugs. Hypotension to 70 mm Hg was reached by sodiumnitroprusside or by Arfonad, or by an association of both of these. The doses were analogous to those employed in exclusively pharmacological anaesthesia. The exclusion or marked reduction of analgesic drugs by the application of this method allows an immediate recovery of consciousness. Our experience is based on 19 patients: 9 intracranial aneurysms and 10 brain tumours. Results were good, consisting of early recovery, with reduction of several complications. This method is suggested in cases in which hypotension is dangerous because of the precarious conditions of the patients.

* Bonezzi, C., **':"Bianchi, E., ** Pezzotta, S., ** Lechner, C., ** Brambilla, G. (Ospedale Policlinico "S. Matteo", Universit~ di Pavia, * Servizio di Anestesia e Rianimazione II--Direttore Prof. A. Mapelli, ** Clinica Neurochirurgica--Direttore Prof. P. Paoletti, *** Clinica Pediatrica--Direttore Prof. G. R. Burgio): Atypical

Complications After Ventriculoperitoneal Shunt in the Newborn. Role of the Volumetric Buffering Mechanism. In order to underline the importance of a correct method in neurosurgical general anaesthesia during and after ventriculoperitoneal shunting in newborn affected by congenital hydrocephalus the authors present an atypical postoperative syndrome. The clinical picture includes alterations of the cardiovascular, respiratory, and central nervous systems and of the acid-base balance. Since this syndrome does not seem to be attributable to malfunctioning of the shunt nor to well-known complications associated with a shunting system, the role of volume-pressure ratio in the variations of intravascular blood-cerebrospinal fluid (CSF) equilibrium is considered as regards dynamics of the intracranial fluid


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compartments. CSF stealing by a shunt causes, as rapid compensatory mechanisms, both an internal displacement of the skull bones with sinking of the fontanelles and a rise in intracranial blood volume. This compensatory shifting of blood may cause hypovolaemic shock, the severity of which is proportional to the ratio between the amount required as intracranial buffer and the total circulatory blood volume. The clinical picture, a postoperative complication of ventriculoperitoneal shunts in congenital hydrocephalus with high CSF volume, is probably due to an altered intracranial equilibrium between blood and CSF: there may be an excessive CSF loss outside or an excessive flow of blood inside the central nervous system. Since this syndrome is a specific complication of ventriculoperitoneal shunts the authors suppose that the CSF loss in the peritoneum be a determinant factor in causing the picture. In ventriculoatrial shunts the more balanced flow of CSF into the circulatory system may prevent the appearance of the syndrome. This hypothesis is supported by the similarity of the symptoms to those of haemorragic shock. Also, in these cases a CT scan revealed modified intracranial rations between CSF, blood, brain, and skull, in the absence of other disorders. Other factors causing or precipitating this disease included cardiovascular, respiratory, or renal abnormalities in the preoperative stage and, most important, CSF and blood losses during surgery.

Turazzi, S., Feriotti, G. A., Bricolo, A. (Department of Neurosurgery, City Hospital, Verona, Italy): Head Injury Survivors Who Remain Unconscious. Recent progress in treatment and intensive care for badly brain damaged patients has led to an increase in the number of patients surviving for a long time without recognisable mental function. The heavy toll in time and effort imposed by these patients on the hospital staff and structures, and the economic impact on society at large have in recent time drawn the attention of public opinion and of administrators of public funds. To assess critically the magnitude of the problem we have surveyed the number of patients with prolonged comatose states following injury to the head admitted to the Neurosurgical ICU of Verona City Hospital during tfi~ period 1967/1976. The real incidence of prolonged comatose states is 4~ derived from the total number of acute traumatic comas, and 0.66% from the total population of the patients suffering from injuries to the head. From the final analysis of our data collected over a period of 10 years, it appears that only 94 cases qualify as prolonged comatose states. Of these only 11% are in a vegetative state at the end of one year, and 31~ go on to a socially satisfactory recovery. Is therefore the feeling of the authors that, if a problem exists, it is not overwhelming, and time, effort, and human resources are in the long run definitely not wasted.

Biroli, F., Fascendini, A., * Goglio, A., * Marchiaro, G. (Divisione di neurochirurgia degli ospedali riuniti di Bergamo--Diretta dal Prof. V. Cassinari, * Servizio di microbiologia Ospedali Riuniti di Bergamo): Urinary Infections in Neuroresuscitation. 9 ActaNeurochirurgica, Vol. 48, Fasc. 1~2

130

I. Papo:

The authors ta&ie the problem of hospital infections in a neurological intensive care unit because septic complications are one important reason for the failure of neurosurgical operations, as well as of resuscitation. In particular, they discuss their experiences in coping with urinary infections, and emphasise four main aims: 1. to involve and to make responsible paramedical staff during the phase of studying and formulation of asepsis rules to prevent infections, 2. to set up multidisciplinary work with the contribution of all the different specialists who are interested in the solution of this problem, 3. to revise the methods of using antibiotics in a neurological intensive care unit, 4. result evaluation. G a m b a r d e l l a , G., C a m b r i a , S. (Istituto di N e u r o c h i r u r g i a - - D i r e t = tore Inc. Prof. S. C a m b r i a , Universifft di Messina): The Utility of

ParenteraI Hyperalimentation in Prolonged Coma With Severe Brain Damage. It is well-known that metabolism is remarkably increased in cases of prolonged coma with severe brain damage. In such circumstances the necessary protein and caloric requirements can be obtained only by parenteral hyperalimentation. Estimations of nitrogen balance and serum proteins were carried out in 36 patients with prolonged coma due to severe brain lesions. It is concluded that high caloric parenteral nutrition suppresses catabolic situations, and is beneficial to the clinical courses of these patients. * G a m b a c o r t a , D., ** Consorti, P., * Biancotti, R., ** Zei, E. (* N e u r o & i r u r g i a , *" Anestesia e R i a n i m a z i o n e O s p e d a l e Regionale, Siena): Clinical Elements of Prognosis in Skull--Brain Injured

Patients. A Study of 108 Cases. In this communication the authors hope to assess whether, and to what degree, the severity of the initial neurological situation and age conditioned the prognosis of 108 brain injured patients treated in the neurosurgical intensive-care unit of Siena Regional Hospital from 1974 to 1977. Neurological desease classification was made according to the classification proposed by Posner and Plum (6). Mortality was 46.2~ Age influenced the severity of the neurological syndrome, and also facilitated the appearance of septic respiratory complications, which in their turn aggravated brain disease. Nevertheless, age differences appeared to have a lower prognostic value when the neurological syndrome was very serious from the beginning. Alvisi, C., Borromei, A. ( D e p a r t m e n t of N e u r o s u r g e r y of the U n i v e r s i t y of B o l o g n a - - H e a d : Prof. C. Alvisi): Value of Therapy

With Gamma-Aminobutyric Acid (GABA). The authors, after giving some theoretical and pharmacodynamic opinions on GABA, report their clinical experience for 18 consecutive years with the use of y-aminobutyric acid in cases of central comas, psychorganic postoperative syndromes, and Parkinson's disease.


131

The drug, in the various pathologies listed above, shows a waking effect, with raising of the level of consciousness, a re-equilibrating action in psychorganic involutions, especially acute ones, and considerable antiakinetic activity. After an analysis of the original results obtained, considered especially in the light of the most modern researches into the importance of the GABA-ergie mediation in the basal ganglia, some interesting neurofunctional hypotheses, which are connected with the problem of nervous conduction in human pathology, are advanced. According to these hypotheses the aminoacid works clinically owing to its role as inhibiting mediator (rather than an oxidisable substrate) with extrapyramidal nigro-striatal lesions.

II. Free Topics V i v e n z a , C., D a P l a n , R. ( D i p a r t i m e n t o di n e u r o c h i r u r g i a di V e r o n a ) : The Use of Antifibrinolytic Drugs in the Management of

Subarachnoid Hemorrhage Due to Aneurysmal Rupture. The aim of the present study was to investigate the value of antifibrinolytic therapy in regard to recurrent haemorrhage in a consecutive series of 63 patients with SAH due to aneurysmal rupture treated with tranexamic acid (AMCA) in our Department. For this purpose, the group was compared with another series of 68 patients, admitted to our Department in the years 1968-1969 and not treated with antifibrinolytic agents. When evaluating clinical results, a significant comparison between the opposite groups can be obtained only in the first two weeks after SAH; after this period, the surgical treatment makes comparability more difficult. During the first two weeks, no recurrent haemorrhage was observed in the group of patients treated with AMCA, while 10 recurrent hemorrhages, with 8 deaths, were observed in the control group. The antifibrinolytic treatment, if necessary, was prolonged for four weeks. During this period, 3 recurrent haemorrhages, with one death, were observed in the AMCA-treated group, and 15 recurrent haemorrhages, with I2 deaths, were observed in the control group. Finally, complications related to the antifibrinolytic treatment are discussed. D e R i u , P. L., F a l z o i , A., P a p a v e r o , L., R o c c a , A., Viale, G. L. ( N e u r o s u r g i c a l C l i n i c , U n i v e r s i t y o f Sassari): Local Cerebral Blood

Flow Following Middle Cerebral Artery Occlusion in Rabbits Treated by Omental Transposition to the Brain. Transposition of intact omentum, as well as transplantation of omental grafts with anastomized pedicles, has been proved to develop vascular connections with the underlying brain, thus preventing or minimizing the occurrence of infarcts following experimental middle cerebral artery occlusion. In order to evaluate the effectiveness of the method, which may prove of value in treatment of cerebral ischaemia, investigations of several physiological and biochemical parameters are in progress in this Clinic. The purpose of the present study is to analize the effect of the omental transposition on the local cerebral blood flow following middle cerebral artery occlusion. Adult rabbits of both sexes had the omentum transposed to the right temporoparietal brain convexity, according to the method Goldsmith et al. Three months 9*

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after surgery the right middle cerebral artery was exposed by the transorbital approach and clipped. Animals without omental transpositions served as controls. Local cerebral blood flow was measured by the inhaled hydrogen clearance technique. A femoro-aortic arterial line allowed monitoring of blood pressure and gases. Hydrogen washout curves were recorded prior and immediately after middle cerebral artery occlusion. In the control animals local blood flow in the temporal lobe following arterial occlusion dropped, as a general rule, betow 40% of the values recorded prior to occlusion. In the animals previously treated by omental transposition the effect of the ligation was greatly reduced, the local blood flow in the temporal lobe ranging from 60 to 85% of the normal values. Although preliminary findings on chronic phases of ischaemia reveal that omental transposition does not always radically affect the threshold for infarction, there is evidence that the method is effective in reducing the changes related to the ischaemic insult, at least in the early phases,

Da Plan, R., Pasqualin, A., Scienza, R., Vivenza, C. (Dipartimento di Neurochirurgia di Verona): A Report of 10 Cases of AV Malformations in Critical Areas of the Brain, Operated on With the Aid of Microscope and Deep Controlled Hypotension. The surgical treatment of AV malformations in critical areas of the brain is still debatable; this is due to the frequent association of these lesions with only epileptic seizures and minimal or no neurological deficits. In recent years, reports of this type of AV malformation with successful surgical treatment have appeared in. the literature. Ten cases of intracranial AV malformation with severe surgical problems, either on account of the area of brain involved, or the preoperative symptoms, were operated on in our Department. Outstanding advantages were obtained in these cases from the use of the operating microscope and deep controlled hypotension, allowing removal of AV malformations with sparing of critical areas involved. All cases had successful results. Control angiography, performed in all cases, gave the proof of complete removal of the lesions.

Cecotto, C., Janes, P. P., de Nardi, F. (Ospedale Generale Regionale, Divisione Neurochirurgica, U dine): Follow Up of 702 Cases of SAH Considerations on the Aetiology. The authors report 702 cases of SAH, and consider the problem of spontaneous SAH by using CT. We have carefully examined the rich literature on the subject, relevant to the clinical, histological, and experimental aspects of the problem, and we conclude that the presence of an intracranial aneurysm is due to an acquired pathological condition, associated with the particular nature of the cerebral circulation which causes a sectorial abiotrophy of the arterial wall and the consequent development of the aneurysmal sac.

Castellano, F., Profeta, G. (Neurosurgical Division, Cardarelli Hospital, Naples): Carotid Ophthalmic Aneurysms.


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In Locksley's cooperative study (1966) we find the term "carotid ophthalmic" for the first time, but Jefferson (1937) and Dandy (1944) had already directed their attentions to this topic. We report 15 cases, admitted to Cardarelli Hospital in Naples in the period 1968-1977: nine of them were operated on, three refused surgery, and three were not operated on, because of their clinical status. In seven patients the aneurysm was approached directly: in six the aneurysm beck was clipped, and in the seventh we achieved a reduction in size. In one patient intracranial and extracranial trapping were performed, and in one patient the carotid artery was progressively closed. There was no death, and long term results have been excellent. In only one case was there visual impairment after surgery. The authors, after consideration of anatomical data (Dawson), clinical manifestations, and surgical technique problems, come to these conclusions: 1. Angiotomography is very useful in showing the neck of the aneurysm, which is not always easily detectable. 2. The direct microscopical approach is better than carotid ligature in the neck, and this point of view is in agreement with recent experiences of Almeida, Sengupta, Guidetti, and Ya~argil. 3. It is always advisable to prepare the carotid artery in the neck, for possible temporary ligature.

Vivenza, C., Da Plan, R., Pasqualin, A. (Dipartimento di Neurochirurgia di Verona): A Report of a Case of Huge A V Malformation With Spontaneous Cure Demonstrated on Angiography. Very few cases of AV malformations with spontaneous cure demonstrated on angiography are reported in the literature. The case presented here has some points of interest : 1. the huge AV malformation, already evaluated 8 years before, had been considered not amenable to surgical treatment at the time of diagnosis because of its size and the area involved; 2. the appearance of mild but progressive neurological symptoms (increased frequency of epileptic seizures and mild left hemiparesis) suggested a possible surgical treatment, due to the advances in surgery and anaesthesiology; 3. the disappearance of the lesion was shown by a new angiographical study: this finding suggests that one should repeat angiography when planning surgical treatment for an AV malformation diagnosed years before; 4. the CAT scan, in spite of angiography, showed hyperdensity at the site of the lesion, without changes with contrast medium. On skull X-ray, an increase in size of a previous small area of calcification was also noted; 5. clinical improvement was achieved following more adequate antiepileptic therapy.

Cerillo, A., Vizioli, L., Corriero, G., Tedeschi, G. (Universit~t di Napoli, Clinica Neurochirurgica, Naples): Intracerebral Haemorrhage: an Attempt at Statistical Assessment for Operability. The authors report a series of 110 patients with intracerebral haemorrhage: 85 underwent surgery and 25, although suitable candidates for surgery, refused operation. The results are assessed in order to indicate the operability, in relation to the

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coma level, age, site of the haemorrhage, mode of onset, metabolic values, cardiocirculatory diseases and interval between accident and operation. With each of the parameters considered, a numerical value has been arbitrarily assigned in relation to their prognostic incidence. In this way we were able to determine a "total" value in order to assign patients to groups of different surgical risk.

Briani, S., Gagliardi, R., Guizzardi, G., Ammannati, F., Sottini, M. (Neurosurgical Division, Arcispedale S. M. Nuova, Florence): Middle Cerebral Artery Thrombosis; Autolysis of the Platelet Thrombus Following STA-MCA By-Pass. We report the clinical case of a patient suffering from middle cerebral artery acute occlusion and operated upon, within four hours, with the aim of a radical embolectomy. At surgery an extensive thrombosis of the MCA horizontal tract was found: therefore, it was impossible to achieve a complete disobliteration of the vessel, and a STA-MCA microsurgical anastomosis was performed. An angiographic control, one month after the intervention, showed a complete restitution of the blood flow in all the branches of the MCA and in the whole homolateral hemispheric circulation. The clinical follow up and the angiographic control suggest several very interesting considerations on the choice of surgical treatment in acute occlusive cerebrovascular disease.

Colombo, F., Curri, D., Benedetti, A. (Divisione di Neurochirurgia dell'Ospedale Civile di Vicenza--Head: Prof. A. Benedetti): A Case of Broken Heifetz' Clip. A case of angiographically demonstrated broken Heifetz' clip is presented. As angiography showed no filling of the aneurysm, reoperation was not considered necessary. The cause of the fracturing of the clip remains unknown. Some hypotheses are suggested.

Gerosa, M., Gasparotto, G., Carteri, A. (Universit~ degli studi di Padova, Istituto di Neurochirurgia, Padova): The Immune Biology of Malignant Gliomas: the B- and T-Cells-Dependent Immune Response. The immunological evaluation of primary malignant intracranial neoplasms is still a matter of some discussion, inasmuch closely related to unsolved biological problems. The authors report a two years experience concerning the immunological monitoring of malignant gliomas, with particular regard for the B- and T-cellsmediated immunity and delayed hypersensitivity reactions. Some of the main pre-operative findings--the clear depression of delayed hypersensitivity reactions; the relevant failure of the T-cell-dependent immune response, currently identified by Ea-RFC and blastigenesis tests; the peculiar enhancement of spontaneous cytotoxicity; - - should in time assume a prognostic meaning for immuno-histological considerations. The evolution of the post-operative immunological follow up is discussed.


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* Mosca, L., ** Paoletti, P., ** Baldini, M., ** Princi, L. (* Institute of Anatomical and Histological Pathology, State University of Pavia--Chairman: Prof. L. Mosca, ** Institute of Neurosurgery, State University of Pavia--Chairman: Prof. P. Paoletti): Empty Sella and Rathke's Cleft Cyst. Hypophyseal narrowing and sellar remodelling can depend on extracranial (A), perisellar (B), or intrasellar (C) causes. Headaches, rhinorrhoea, visual-hypothalamic-pituitary defects, or no symptoms at all can arise. A. Sella turcica ballooning in obese hypertensive women can derive from hypoventilation, increased venous and intracranial pressure, CSF and cavernous sinus circulation impairment. B. Diaphragma sellae hypoplasia with subarachnoid space extension to sellar cavity (arachnoid cyst) is of major importance. Sphenoid sinus mucoceles and cystic craniopharyngioma must be considered for differential diagnosis. Ependymal cysts may bulge through the infundibulum. C. Among pituitary lesions: atrophy, apoplexy, infarcts, necrosis, fibrosis in apparently normal (especially diabetics) or in particular cases (pregnancy, primary tumours); surgery, radiation, yttrium implantation with possible circulatory disturbances in chiasma and optic nerves. True cysts must be considered. Their origin can be from: neuroepithelium pinched off to form usually ependyma-lined cavities; Rathke's pouch remnants; cystic evolution of follicles sometimes visible among normal adenohypophyseal structures. All cysts can contain clear yellow fluid, mucin, colloid, haemorrhage ddbris, cholesterol crystals, inflammatory cells, macrophages, giant cells. When properly preserved, they can be lined by ciliated, columnar-cuboidal, flattened epidermoid epithelium with possible secretory goblet cells. All these structures can appear either in Rathke's pouch or in neuroepithelium derived cysts. Surgery, even if unable to remove the entire cyst, seems equally satisfactory when the cystic content and part of the epithelial membrane are withdrawn. On the basis of our surgical and pathological experience new cases of empty sella due to pituitary cysts are presented.

* Cecotto, C., * de Nardi, F., ** Leonardi, M. (Ospedale Generale Regionale, Udine, * Divisione di Neurochirurgia--Primario: Prof. C. Cecotto, ** Sezione di Neuroradiologia, Istituto di Radiodiagnostica 1~ Primario Prof. M. Corsi): Interest of Threedimensional CT in the Sf~dy of Parasellar Lesions. The traditional neuroradiological examinations do not allow a complete study of parasellar lesions. It may be difficult to evaluate the relationships between a mass and the surrounding anatomical structures. The three dimensional CT may provide this kind of information and, moreover, complementary findings useful to differential diagnosis and surgical approach.

Luccarelli, G., Migliavacca, F. (Neurosurgery Division, Istituto Neurologico "C. Besta", Milan): Follow-Up Results in 68 Patients Operated on for Dermoid and Epidermoid Turnours of the Central Nervous System.

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From 1947 to 1977, 68 patients with dermoid and epidermoid tumours of the central nervous system have been operated on at the Istituto Neurologico of Milan. Although such tumours are benign, in the past years partial removal was adopted to avoiding damage to the surrounding nervous structures. The aim of this study is to analyse the follow-up results carried out in a period of 4 months to 23 years, assessing thereby the results achieved either by partial or total removal of the tumour.

Porta, M., Rougerie, J. (H6pital Foche, Department of Neurosurgery, Suresnes): Considerations on Surgical Treatment of Subdural Haematomas in Infants. In spite of the frequent occurrence of HSD in infants in the first two years of life, a general agreement concerning its management and treatment is still to be reached. Moreover, the different pathological aspects of these collections in the subdurai space and the basic mechanism of fluid accumulation (by haemorrhage or effusion) has to be better defined. In order to treat subdural haematomas in infants the authors feel the need of determining the degree of intracranial pressure that characterizes "acute" and "chronic" phases. In the acute stage treatment is quite simple: repeated subdural taps are indicated, more seldom burr holes or craniectomy. Of course every possible event, like dehydration or infection, if present, has to be treated in order to prevent SDH recurrence and in every case the success of therapy has to be documented by radiological examination. This acute subacute stage is followed by a later chronic stage, with normal or increased ICP. The possible chronic evolution and the high risk of recurrence of HSD in infants emphasize the need for a specific and reliable treatment for this pathological condition. The surgical procedure that is proposed by authors would mainly consist in membrane excision, reduction of cranio-cerebral disproportion, and anterior displacement of the midline bony bridge with restoration of the normal junctional angle between cerebral veins and superior sagittai sinus. This technique seems to produce a more physiological condition, even if its use is recommended only when a craniocerebral disproportion has been clearly detected.

Maira, G., di Rocco, C., Belloni, G., Borrelli, P., Iannelli, A., Vignati, A. (Istituti di Neurochirurgia e Radioiogia, Universit~ Cattolica, Roma, e Servizi di Endocrinologia a Pediatria, Ospedale Bambino Gesfi, Roma): Transphenoidal Microsurgery of Chromophobe Pituitary Microadenomas in Children With Isolated GH Deficiency. Four children with prepubertal growth failure (growth rate prior to admission: 2 to 3 cm/year), of ages ranging between 6 and 12 years, were initially regarded as hypopituitary idiopathic dwarfs. All of them were characterized by an isolated growth hormone (GH) deficiency, which was apparent in the basal condition and following L-Dopa and hypoglycaemia stimulation. The secretion of the remaining pituitary hormones was normal, as demonstrated by a complete laboratory and endocrine evaluation (AM and PM cortisol, T3-T4, TSH, FSH, LH, electrolytes, calcium and phosphorus serum levels). In three of these children the radiological picture (standard and hypocycloidal


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tomography) of the sella turcica was regarded as "border-line" because of the presence of minimal erosion or depression of the floor or of rounding of the profile. Radiological examination was definitively negative in the fourth child. All the patients underwent a CT scan which disclosed a localized nodular area of hyperdensity within the sella, following the contrast medium administration. At surgery (transphenoidal approach, using the operating microscope) the nodular density was found to correspond to a microadenoma, which could be selectively removed. The pituitary gland was easily recognized and respected. Histologically, the microadenoma was of chromophobe type in all the cases. The operation was followed by an immediate improvement of the growth rate, with an enhancement of the G H secretion (follow-up 9 to 13 months). These results seem to suggest the importance of the association between an isolated G H deficit and a positive CT scan in the early diagnosis of growth failure due to an organic purely intrasellar lesion in children.

Zampieri, P., Giordano, R., Pensabene, V., Carteri, A. (Department of Neurosurgery, Institute of Pathology, University of Padua): Cerebellar Astrocytomas in Children. Long Term Study. Fifty-five cases of children with cerebellar astrocytomas were operated on at the Neurosurgical Institute of the University of Padua from 1952 to 1966. In this series there were patients with a median lesion (vermis), with a lateral lesion (cerebetlar hemisphere), with a lesion involving both the vermis and one cerebellar hemisphere, or with a lesion of the fourth ventricle. Operative mortality was 18~ (10 cases). The present study concerns 25 of the 55 patients (45~ Survival was more than 10 years. In perticular 6 patients have survived more than 20 years, 8 patients 15 to 20 years, and 11 patients 10 to 15 years. The clinical symptoms, the pathological findings, and the type of treatment (complete or incomplete removal, irradiation) are presented. The quality of survival (functional status, neurological deficits, recurrence of the tumour) is illustrated. The authors point out that complete removal gives the best result, but also an incomplete removal can give a long term survival (in this series 10 cases have survived 10 to 23 years).

Carbonin, C., Alexandre, A., Volpin, L., Benedetti, A. (Ospedale civile di Vicenza, Divisione di Neurochirurgia, Vicenza): Surgical Treatment of Arachnoid Cysts of the Sylvian Fissure. This report concerns the surgical treatment of four cases of arachnoid cysts of the Sylvian fissure: in two cases a cystoperitoneal shunt was performed, with a satisfactory result; the other two were treated by radical intervention with excision of the cyst. The first of these was operated on as an emergency, following a craniocerebral injury, on the suspicion of an acute subdural haematoma, and died 10 days later. The second patient, showing also bony alterations consisting in elevation and forward dislocation of the small sphenoidal wing, was successfully treated after a complete neuroradiological study. Postoperative CT scan demonstrates reexpansion of temporal lobe. The authors review the pertinent literature, and consider the anatomopathological aspects and the natural history of the disease.

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Lechner, C., Pezzotta, S., Paoletti, P. (Ospedale Policlinico S. Matteo, Clinica Neurochirurgica, Pavia): Giant Meningioma in a Child Aged 9. The case presented is of particular interest due to the rarity of this oncotype in childhood. The data in the literature regarding this subject is briefly discussed. Our findings are, for the most part, in agreement with those in the literature. In our patient, too, the tumoural mass was extremely voluminous (300 g) so as to merit the term "giant" meningioma. It was is not in contact with the dura mater, and the initial neurological picture was due to endocranial hypertension. Focal signs appeared later. The clinical and neuroradiological diagnostic process, the total surgical removal of the tumour, and the postoperative period were described and illustrated. The patient underwent a clinical follow up which included periodical CT scans. The radical ablation of the turnout, with complete disappearance of the neurological symptoms, was ascertained.

Caldarelli, M., di Rocco, C., Rossi, G. F. (Istituto di Neurochirurgia, Universit~t Cattolica, Rorna): CerebrospinaI Fluid PressureVolume Relationship in Children. The introduction into clinical neurosurgical practice of the subarachnoid constant infusion manometric test (IT) for studying the CSF absorptive capacity by Katzman and Hussey, was followed by many reports on the value of the test as a diagnostic aid for surgical indication in hydrocephalic patients. However, there are only a few observations specifically related to infants and children. In recent years, 115 IT's have been carried out in paediatric age patients in the Neurosurgical Institute of the Catholic University of Rome, either in the diagnostic phase or in the postoperative evaluation. For analytical purposes, the children have been divided into three main groups on the grounds of the clinical and neuroradiological findings: 1. hydrocephalus, 2. cerebral atrophy, 3. craniosynostosis or microcephaly. Results indicating a severe impairment in the CSF absorption have been obtained in all the hydrocephalic children in whom the neuroradiological findings suggested a ventricular dilatation under tension (these patients were characterized by a very steep linear slope--2 cm H~O/min--of the Pressure/Volume (P/V) curve during the test. Conversely, CSF absorption deficit was ruled out in the children with neuroradiological evidence of cerebral atrophy as well as in craniosynostotic children with early fusion of a single cranial suture (P/V curve slope: 0.55 cm H20/min). A moderate deficit in the CSF absorption was found in some children with the clinical picture of slowly progressive hydrocephalus (P/V curve slope below 1.3 cm H20/min). Finally, CSF absorption mechanisms defective in the low pressure ranges but normal at the high pressure values were apparent in children with a multiple cranial suture early fusion.

Longatti, P. L., Pellone, M., Scanarini, M., d'Avella, D., Carteri, A. (Istituto di Neurochirurgia dell'Universit~ di Padova): A Method for Evaluation of Shunt Independent Arrested Hydrocephalus. After a brief review of the literature, a definition of "shunt independent arrested hydrocephalus" is given. Different opinions have been expressed about: the need for a lifetime-functioning CSF shunt; our clinical experience is discussed.


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Since 1977 a method of ICP recording through the multipurpose valve (MCV) has been devised. As MPV is shut off, ICP rises and acute hydrocephalus ensues. The high ICP develops within different periods of latency. The test is interrupted when the first "plateau waves" appear. Twenty-two hydrocephalic children treated with a ventriculo-peritoneal shunt (V-P) with the MPV have thus been evaluated. The latency time varied from five minutes to four hours; different ICP tracing patterns were obtained in every patient but in none was a normal pressure observed. The morphology of the ICP recording tracings and the length of the "time latency" can be indicative for prognostic purposes. However, we think that the best way to follow up the evolution of this hydrocephalic syndrome is by performing repeated controls. L o n g a t t i , P. L., Pellone, M., C i s o t t o , P., L i c a t a , C., C a r t e r i , A. ( I s t i t u t o di N e u r o c h i r u r g i a dell'Universit~t di P a d o v a ) : CSF Shunt

Systems Pressure-Flow Rate Evaluated in HydrocephaIic Children. Many methods of assessing the patency and the adequacy of CSF shunt systems have been suggested, but few experiences of their pressure-flow rate evaluations have been reported. For two years we have been attempting to determine the pressure-flow curves, i.e., resistance curves, in CSF shunts placed in hydrocephalic &ildren, using the method developed in the laboratory by Fox in 1973. After puncture of the valve reservoir, ICP is recorded; thus the CSF, spontaneously flowing from the ventricular catheter, both at opening pressure and at negative pressure of 10 H.20 cm, is gravimetrically evaluated. The resistance of the distal catheter is produced by its perfusion with physiological solution, at both 15 and 30 H20 cm. Thirty-two hydrocephalic patients treated with CSF diversionary V-P shunts have been tested. For each case we obtained a pressure-flow curve, In thirteen cases we observed that the patency was assured, but the resistance of the shunt was increased and the adequacy lost. In four cases postoperative assessments have been made. After a review of the literature the advantages of this very simple method are discussed. * B a l d i n i , M., *Princi, L., ** V i v e n z a , C., *** T o n n a r e l l i , G., ** Signorini, G. (* I n s t i t u t e o f N e u r o s u r g e r y , S t a t e U n i v e r s i t y o f P a v i a - - C h a i r m a n : P r o f . P. P a o l e t t i , ** D e p a r t m e n t o f N e u r o s u r g e r y , B o r g o T r e n t o H o s p i t a l , V e r o n a - - C h a i r m a n : P r o f . G. D a l l e O r e , *** D e p a r t m e n t o f N e u r o s u r g e r y , C i v i l H o s p i t a l , L e g n a n o - - C h a i r m a n : P r o f . G. C. N i c o l a ) : Thoracic Disc Hernia Surgery 1 Thoracic disc protrusions are quite rare. About 250 cases have been reported. The prognosis is often poor in spite of surgical treatment; an objective improvement was observed in 40~ of surgical cases, which represents 3-5~ of the total reported cases. Clinical findings. Nine cases of thoracic disc posterior protrusion are presented: six men and three women, aged between 18 and 61; in two patients kyphosis is considered the most important factor in the genesis of these lesions. In the lower 1 The full paper will be published in Acta Neurochirurgica.

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third of the thoracic spine disc hernias were more frequent (five cases); in the middle and upper third there were respectively three and one; but five disc dislocations out of nine were median. Some clinical features are suggestive of the diagnosis: pain in the back always present in different intensity, referred intermittent or continuous root pain (four cases), bilateral or unilateral paresis in all patients, bilateral or unilateral skin vibration sense hypaesthesia in six cases, including the abdominal regions in two. In only one case was sphincter insufficiency observed. Surgery. After a period, varying from five days to a month from the beginning of nervous symptomatology, we performed a hemi- or complete laminectomy, adding a lateral incision for postero-lateral approach. The lateral opening may be improved by removing the transverse process, exactly at the myelographic and tomographic level. Following spinal cord decompression by dural incision we reconstructed the dura. Results. Patients observed after at least six months from surgery show in six cases regression of motor loss and sphincter symptoms. However, there was no permanent postoperative deterioration. P r o f e t a , G., M a g g i , G. ( N e u r o s u r g i c a l D i v i s i o n - - C h i e f : P r o f . F. C a s t e l l a n o , C a r d a r e l l i H o s p i t a l , N a p l e s ) : Terminal Ventriculostomy

for Syringomyelia. Report of Two Cases. The pathogenesis of syringomyelia is not yet known, and the surgical management is still an open problem. Terminal ventriculostomy, as proposed by Gardner et al. (1977) to treat "communicating" syringomyelia could be the alternative approach instead of cranio-vertebral decompression or subarachnoid shunt of the syrinx. This operation was performed by the authors in two cases. In both of them there was postoperative improvement of the neurological symptoms although in only one did the conus appeared enlarged and CSF escape after excision of the filum. In the author's opinion the main problem is the difficulty in preoperative diagnosis of "communicating" syringomyelia and particularly in determining the size of the syrinx. The best diagnostic procedure for this condition is pneumoencephalography, although sometimes the definitive diagnosis can be made only at surgery. This operation is simple and might be curative for "communicating" syringomyelia, especially when there are no associated malformations. D i L o r e n z o , N . , S a v i n o , St., N i c o l e , S., S o r a n o , V. ( I n s t i t u t e of N e u r o s u r g e r y , R o m e M e d i c a l School): Aneurysmal Bone Cysts of

the Spine. Report of Seven Cases Treated by Surgery Only. Aneurysmal bone cysts are a well-defined pathological entity (Jaffe and Lichtenstein 1942)..Several authors have outlined the clinical and radiological features of such lesions, leaving the treatment an open question (surgery, radiotherapy, or both). We report seven cases of aneurysmal bone cysts of the spine surgically treated at the Institute of Neurosurgery, University of Rome. None received postoperative radiotherapy. Long-term outcome was excellent in all cases 14, 13, 11, 6, and 3 years after operation; the last case, operated upon 4 months ago, is now symptom-free.


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Keeping in mind the above results and the potential hazards of radiotherapy, i.e., radionecrosis and malignant degeneration, is our opinion that this essentially

benign lesion should be treated by surgery only.

Giua, G., Luccarelli, G. (Neurosurgery Division, Istituto Neurologico "C. Besta", Milan): Closed Space Infection (Discitis) as Complication After Removal of Herniated Disk. Discitis intervertebralis after surgical operation for herniated disk is a rare complication: reports give an incidence that varies from 0.2~ to 2~ Discitis intervertebralis has to be suspected when, in the immediate postoperative course or up to a few months after operation, lumbosacral pain appears. This alters the normal postoperative course and cannot be explained by disc herniation recurrence. The signs of this disease, beside the pain, are increased erythrocyte sedimentation rate, and X-ray findings, consisting of narrowing of intervertebral space, bone erosion, sclerosis of the intervertebral bodies, and bone fusion. Tomograms are essential for early diagnosis. In the last 15 years 20 cases of discitis have been observed at the Istituto Neurologico of Milan. Sixteen of them had been operated on by us and four in other hospitals. Our 16 cases represent 0.6% of 2,530 disc hernias operated upon in that period. Immobilization, antibiotics, and antiphlogistic therapy were effective treatment.

Bianchi, R., Canapicchi, R., Molea, N., Parenti, G., Tusini, G. (Universit~ di Pisa, Istituto di Neurochirurgia, Pisa): Scanning in the Diagnosis of Neoplastic Diseases of Bone in the Spine. We have studied some patients affected by primary and secondary neoplastic diseases of bone in the spine putting in relation the X-rays and bone scanning using 99 mTc pyrophosphate. It may be observed that bone scanning is positive earlier than X-rays in demonstrating bone neoplastic diseases. Furthermore, bone scanning gives a more accurate demonstration of the extension, distribution, and number of the bone neoplastic lesions. On the other hand, because of the poor resolution of bone scanning, it is always necessary to have a radiographic study for comparison.

* Gambacorta, D., * Scarf6, G. B., ** Forzini, L., ** Ferrari, F., * Reale, F. (* Neurosurgical Department, Regional Hospital, Siena, ** Institute of Radiology, University of Siena): Computed Tomography of the Lumbar Spine. Preliminary Report. Forty patients were submitted to CT of the lumbar spine. Twenty patients had no clinical signs of lumbar spine or root disease. In 15 of these the normality was confirmed by simple X-ray and CT studies. Twenty patients were suffering from various lumbar pathologies: spinal stenosis, spondyloarthrosis, metastatic tumours, traumatic lesions, and postoperative pain. Each of them were submitted to X-ray, radiculography, CSF examination, and CT without contrast media. Many examples are given to show the effectiveness of CT in demonstrating the anatomical details of the lumbar spine, normal or pathological.

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CT, compared with other radiodiagnostic procedures, appears superior in careful assestment of the morphology of the lumbar canal, articular joints, and radicular foramina. The method is illustrated.

Bricolo, A., Dalle Ore, G. (Department of Neurosurgery, City Hospital, Verona): Experience With Percutaneous Cervical Cordotomy. Thanks to the pioneering effort of Mullan et al. and their introduction of the percutaneous approach to the spino-thalamic tract at cervical level, a new era was open for the relief of intractable cancer pain. Nowdays, percutaneous cordotomy performed under local anaesthesia has becomed so perfected and safe as to replace altogether the open technique. Furthermore, in the hands of experienced surgeons it can afford relief from intractable pain due to malignancies in almost terminal patients without adding the stresses and dangers of traditional cordotomy with better selectivity and precision. One hundred and eighty procedures were performed the authors with highly satisfactory results in 93~ of cases. Life-threatening complications were completely avoided, and minor complications were kept at very low level. Major guidelines adopted are: a) patient's full cooperation, b) detailed neurological examination to identify non-surgical patients with anaesthetic lesions, c) local anaesthesia to allow complete patient's awareness during the procedure, d) a lateral approach between C 1 and C 2 vertebrae, e) X-ray identification of the dentate ligament and anterior border of the cord by Myodil, f) insertion of electrode tip into the cord under continuous impedance monitoring, g) neurophysiological localization of the spino-thalamic tract by electrical stimulation, h) radiofrequency produced lesion and i) mandatory delay of at least a week if a controlateral procedure is necessary. Because of the high accuracy of localization through the neurophysiological stimulation and the selectivity of the radiofrequency lesion, analgesia at a high cervical level is easily obtained.

Graziussi, G., Terracciano, S., Granata, F. (Divisione di Neurochirurgia, Ospedale San Gennaro, Napoli): Percutaneous Trigeminal Thermal Rhizotomy Without General Anaesthesia. The introduction of Sweet's technique represents a great progress in the treatment of trigeminal neuralgia. Radiofrequency percutaneous controlled thermal rhizotomy, in fact, combines the advantages of percutaneous methods (safety, brevity) with the advantages of "open" techniques (efficacy, direct control of the lesion). Although reduced, some complications are still present: they are mainly represented by unwanted analgesia or anaesthesia in one or more trigeminal divisions. Ultrashort anaesthesia and staged increments of five degrees do not permit avoidance of such a complication in all cases. Sweet has, in fact, observed, after a five degree increment of heat, transformation of an area of mild hypalgesia into an area of deep anaesthesia. This complication is particularly serious when it occurs in the first division area. Furthermore, in some patients with serious cardiac, hepatic, or renal insufficiency, repeated ultrashort anaesthesia may represent an added risk to the procedure.


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For these reasons we have adopted, in selected cases, the technique of thermal rhizotomy without general anaesthesia. This technique, quoted by Sweet, consists of making thermal lesions in the wakeful patient, with very slow heating ( 89 degree increments), and with continuous testing of sensation. In 92 percutaneous procedures we have adopted this technique 20 times. The results have been identical to those obtained with the standard technique, but in no case have we observed sensory or other complications.

Matricali, B. (Department of Neurosurgery, University Hospital, Leiden): Continuous Spinal Drainage in the Treatment of Pre- and

Postoperative Cerebrospinal Fluid Fistulae. By lowering the cerebrospinal fluid pressure many spontaneous post-traumatic and postoperative CSF fistulae will seal without problems. Even long-standing leaks will heal without need of surgery. Originally CSF pressure was lowered by repeated lumbar punctures, but this is uncomfortable for the patient and there is no possibility of checking the CSF pressure level continuously. For continuous drainage a catheter is applied intradurally and connected to a sterile bag. By raising or lowering an interconnected drip chamber the CSF pressure can be very easy and safely controlled. The indications for continuous spinal drainage and period of its application are: 1. Delayed post-traumatic and postoperative fistulae: one patient was drained for 45 days with final success. 2. In all cases of surgically closed fistulae: drainage period about 15 days. 3. In all cases in which a watertight closure of the dura is impossible: drainage period at least 10 days. 4. In all patients, with trans-sphenoidal pituitary surgery. If no CSF flows during the operation the drain is removed at the end of intervention. If CSF leakage clearly occurs the drainage is continued for seven days. This holds also true in case of doubt about a leakage. Up to now continuous spinal drainage has offered no problems of infection. The collected CSF is tested daily bacteriologically and cytologically. Patients often complain of radicular pain from catheter irritation. Partial withdrawal of the catheter is then necessary and effective. In one patient radicular impairment has persisted. References

1. Aitkeen, R. R., Drake, C. G., Continuous spinal drainage in the treatment of postoperative cerebrospinal fluid fistulae. J. Neurosurg. 21 (1964), 275--277. 2. McCallum, J., Maroon, J. C., Jannetta, P. J., Treatment of postoperative cerebrospinal fluid fistulas by snbarachnoid drainage. ]-. Neurosurg. 42 (1975), 434--437. 3. Ommaya, A. K., Spinal fluid fistulae. Clin. Neurosurg. 23 (1976), 363--392. 4. Vourc'h, G., Continuous cerebrospinal fluid drainage by indwelling spinal catheter. Brit. J. Anesth. 35 (1963), 118--120. 5. Findler, G., Sahar, A., Beller, A. J., Continuous lumbar drainage of cerebrospinal fluid in neurosurgical patients. Surg. Neurol. 6 (1977), 455--457.

** Nicole, S., * Palma, L., * Refice, G. M. (* Institute of Neurosurgery--Head: Prof. B. Guidetti, Rome University, ** 2nd Chair

144 for

I. Papo: Neurosurgery--Head:

Prof.

A.

Fortuna,

Rome

University):

Primary Orbital Expanding Lesions. Report of 104 Cases. A series of 104 primary orbital expanding lesions, surgically treated, consisting of 20 malignant and 84 benign lesions, is presented. The pathological, clinical, and roentgenological features, and the long-term follow up are analysed. Proptosis was the most frequent clinical sign (98~ followed by limitation of ocular movements (44~ and by visual function impairment (32~ Computerized tomography (CT) scan was very effective in delineating the relations between lesions and anatomical landmarks. A good surgical result was achieved in the majority of benign lesions, the subfronral-extradural approach to the orbit being sufficient in most cases. ** N i c o l e , S., '~"P a l m a , L. (* I n s t i t u t e of N e u r o s u r g e r y - - H e a d : P r o f . B. G u i d e t t i , R o m e U n i v e r s i t y , ** 2 n d C h a i r for N e u r o s u r g e r y - H e a d : P r o f . A. F o r t u n a , R o m e U n i v e r s i t y ) : Idiopathic Orbital

Pseudotumor. By the term orbital pseudotumor is meant any idiopathic inflammatory condition of the orbit acting as a mass lesion. Twenty-one patients with orbital pseudotumors have been operated upon in the Institute of Neurosurgery of Rome University. The usual clinical picture includes abrupt proptosis, chemosis, pain, and an uneven evolution. Correlation is suggested between computerized tomography (CT) scan and pathological features. Visual function impairment prompts surgery, otherwise conservative treannent with steroids and CT scan controls are advised. D ' A v e l l a , D., S c a n a r i n i , M., M i n g r i n o , S. ( I s t i t u t o di N e u r o chirurgia, P a d o v a ) : The Subarachnoid Continuous Recording of

Intracranial Pressure (SAP) in Clinical Practice. Review o~ 150 Cases. The results obtained by recording intracranial pressure with a polyethylene catheter or a needle placed in the subarachnoid lumbar space (SAP) in 150 cases from 1975 to 1978 are reported. Many authors stressed the limits of this method, above all the difficulty of long term recording. However, in our opinion, the method presents unquestionable advantages when used as a pre- and postoperative routine. The SaP is particularly suited for hydrocephalic syndromes, subarachnoid haemorrhage, and pseudotumor cerebri; the only limitation is represented by intracranial expanding lesions and any other pathology that interferes with cranial and spinal CSF communication. We also performed simultaneous ventricular and lumbar ICP recordings which served to confirm the identity of ICP measured at both levels. The average time of recording was between 6 and 8 hours, up to a maximum of 18 hours. No complication was observed in the 150 monitored cases. Sironi, V. A., C a b r i n i , G. P., M a r o s s e r o , F., R a v a g n a t i , L., ** P o r r o , M. G. ( N e u r o s u r g i c a l I n s t i t u t e of the U n i v e r s i t y , M i l a n , *'~" " M . N e g r i " P h a r m a c o l o g i c a l Research I n s t i t u t e , M i l a n ) : Some


145

Data on Anticonvulsant Drugs Concentrations and Distribution in Human Brain. Method. Observations were carried out in 10 patients (8 males and 2 females) affected by non-tumoural partial epilepsy who received surgical treatment. After depth EEG study by chronic stereotactically implanted electrodes, six patients were submitted to unilateral temporal lobectomy, two to parietal cortectomy, one to frontal lobectomy, and one to fronto-temporal lobectomy. All the patients had been receiving antiepileptic drugs at therapeutic doses and plasma levels. In eight cases phenobarbitone (PB) was associated with other antiepileptic drugs: diphenylhydantoin (DPH) in six cases, carbamazepine (CBZ) in one case, carbamazepine and clonazepam (CNP) in one case. Two patients were treated with CBZ alone. Brain/plasma concentrations ratio, brain/CSF concentrations relationship, and topographic distribution of PB, DPH, and CBZ were investigated. Results. A statistically significant correlation between plasma and brain concentration does exist for PB and DPH. This correlation is even better between brain and CSF concentrations. Assuming that CSF concentration is an expression of the free diffusable drug fraction, from the study of brain/CSF ratio it is possible to state that PB and DPH can reach in the cerebral cortex a concentration respectively 12 and 8 times higher than CSF concentration. Antiepileptic drugs are uniformly distributed in the gray and white matter, with only a slight trend of D P H and CBZ to reach higher concentration in the white matter. Considering regional distribution, PB shows a lower concentration in the temporal lobe in comparison with fronto-parietal areas. As far as DPH is concerned, we found higher D P H concentration in the temporal lobe than in frontal and parietal lobes. For CBZ no evaluation of cortical distribution was possible. Rhinencephalic structures seem to have similar concentrations to the corresponding gray matter of temporal cortex for PB, DPH, and CBZ. In one case, in the amygdala PB concentration was higher that in Ammon's horn and in the gray matter of the same temporal lobe. * B u o n a g u i d i , R., C a r p i , A., F e r d e g h i n i , M., N i c c o l i n i , A., Lev a n t i , C., B i a n c h i , R., * T u s i n i , G . (* N e u r o s u r g i c a l I n s t i t u t e , C e n t r e for Nuclear Medicine, and Institute for Medical Pathology, Univ e r s i t y o f P i s a ) : Measurement of FSH, LH, PRL, and GH Con-

centrations in Cerebrospinal Fluid (CSF) and Their Relationship With Blood Circulation Levels in Patients With Different Neurological Diseases. Follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and growth hormone (GH 5 have been measured in CSF during diagnostic or surgical procedures in the following groups of patients: A. 6 intervertebral discs, B. 3 cerebro-vascular diseases, C. 10 cerebro neoplastic diseases without pituitary or diencephalic involvement, D. 2 multiple sclerosis, E. I porencephaly, F. 1 cervical myelopathy, G. 1 pseudotumor cerebri, H. 1 cerebral atrophy, I. 3 patients with various non-specific neurological symptomatologies. CSF was obtained by lumbar puncture in 20 patients and from the right lateral ventricles during iodioventriculography or during insertion of ventriculo-atrial shunts in the remaining 8 subjects; simultaneously a blood sample was taken to determine the same hormones in the serum. 10 ActaNeurochirurgica,VoI. 48, Fasc. 1--2

146

I. Papo:

The hormonal determinations in CSF gave the following results (mean + 1 SD; ng/ml) :

Patients' group

FSH

LH

A B C D E + F + G + H + I

0.7 0.5 0.5 0.4 0.6

0.6 0.5 0.5 0.5 0.9

+ 0.3 _+ 0.24 + 0.26 + 0.0I + 0.4

+_ 0.2 +_ 0.2 _+ 0.2 + 0.2 + 0.5

PRL

GH

3.8 2.7 3.7 -3.3

0.4 0.5 0.4 0.4 0.4

+ 0.8 + 0.1 + 1 + 0.5

_+ 0.08 _+ 0.08 + 0.06 _+ 0.05 + 0.08

No significant difference was observed between the mean CSF values of FSH, LH, PRL, and G H in the lateral ventricles (respectively 0.47; 0.43; 3.6; 0.4; all ng/ml) and in the lumbar subarachnoid space (respectively 0.6; 0.73; 3.4; 0.4; ng/ml). A significant direct correlation was observed between serum and CSF concentrations of hormones (r = 0.68, p 0.001 for FSH; r = 0.66, p 0.001 for LH; r = 0.57, p 0.05 for PRL; and r = 0.512, p 0.05 for GH). A positive correlation was also found between age (which ranged from 29 to 70 years) and FSH concentrations in CSF (r = 0.523, p 0.05) in the women studied. These data strongly suggest that FSH, LH, PRL, and G H circulate in CSF with concentrations proportional to their serum levels and independently of the different diseases studied.

* Trimarchi, F., ** Baldini, M., ** Princi, L. (* Ophthalmologic Clinic--Chairman: Prof. G. Morone, State University of Pavia, ** Institute of Neurosurgery--Chairman: Prof. P. Paoletti, State University of Pavia): Subjective and Objective Campimetry in the Occipital Lesions. In the majority of cases it is difficult to determine by current parameters whether lateral "homonymous hemianopia" is a consequence os lesion anterior or posterior to the lateral geniculate body. By the use of objective campimetry, it is possible to distinguish clearly between an anterior and a posterior lesion: objective campimetry in fact is determined by the activated retinal area which subsequently generates the pupillo-motor reflex. Since the fibres inherent in the visual pathways and the pupillary fibres remain together during the first two-thirds of the optic tract it follows that every lesion of the optic nerve, of the optic chiasma, and the optic tract involve the two distinct system in the same manner, whereas a lesion to the optic radiations leaves the pupillary tract intact. For precisely this reason the two methods give the same results in anterior lesions of the geniculate body while only the objective campimetry remains unaltered in posterior lesions of the geniculate body. Subjects with lesions anterior or posterior to the geniculate body, lesions clearly shown either by Computerized Axial Tomography or by operation are investigated in this way and consequently the topographic precision is demonstrated by this painless neuro-ophthalmological method.


147

A l e x a n d r e , A., R u b i n i , L., F a r i n e l l o , C., N e r t e m p i , P. ( D i v i s i o n o f N e u r o s u r g e r y - - H e a d : P r o f . A. B e n e d e t t i , O . C . V i c e n z a ) : Electro-

encephalographic and Cognitive Alterations in Severely Head Injured Patients. The authors, who in the past have studied cognitive alterations in head injured patients, develop the hypothesis of assuming EEG modifications of REM sleep during the acute phase and during PTA as a prognostic parameter of neuropsychological defects. This hypothesis is based on the following reported observations: 1. the important role of the hippocampus in memorisation is demonstrated by means of neurophysiological studies in animals and in man following electrical stimulations or surgical ablations; 2. in normal subjects the deprivation of REM sleep markedly reduces short term memory; and, during REM, CBF increases by 150% in some structures among which the temporal lobes; 3. hippocampectomy reduces the global amount of sleep and particularly the amount of REM sleep; 4. Neuropathological observations underline the frequent involvement of hippocampal structures in head injured patients; 5. in head injuries some authors report a reduction of REM, others a reduction of short term memory. In a series of 15 head injured patients sleep electropoligraphic recordings have been performed in the acute phase and thereafter every two months, together with the application of neuropsychological tests (WAIS, RAVEN). The results demonstrate the correlation between these two elements. A quantitative alteration of REM is present in patients with cognitive defects. A complete recovery of REM is observed in patients free from those defects. This correlation may offer, in the acute phase, a further element for the individual prognosis of the head injured patient, when cognitive evaluation by means of classical tests is not yet possible.

* P a g n i n i , P., M e n n o n n a , P., C a g n o n i , G., * C i p p a r r o n e , L., A m m a n n a t i , F. ( N e u r o s u r g i c a l D e p a r t m e n t o f S. M a r i a N u o v a H o s p i t a l , F l o r e n c e , * A u d i o l o g y , U n i v e r s i t y o f F l o r e n c e ) : The Visual

Suppression Test as a Screening Examination for the Evaluation of the Position, Volume, and Relationship With Surrounding Structures of Ponto-Cerebellar Tumors, This communication concerns our own two-year clinical experience of VST as a routine test in otoneurological and neurosurgical examination. During this period, in our Neurosurgical Division we have observed eight patients suffering from ponto-cerebellar angle tumors of varying anatomopathological natures. The VST is performed during caloric stimulations of the ear contralateral to the turnout. This particular test may very often give relevant clinical information about tumour extension towards the cerebellum. When vestibular cerebellar structures, and particularly the s cerebelli, are impaired, VST is pathological: an inhibition deficit or even a true "paradoxical phenomenon" (increase or presence of caloric nystagmus during VST) may be present. I0"

148

I. Papo: Proceedings of the 27th Annual Meeting

C a m b r i a , S., C a m b r i a , M., R a n d a z z o , L. ( I s t i t u t o di N e u r o c h i r u r g i a - - D i r e t t o r e Inc. P r o f . S. C a m b r i a , Universit~t di Messina):

Transbuccal-Transclival Approach for Removal of a Clivus Chordoma: Use of Endoscopy. One case of a clivns chordoma in a 13-year-old girl, operated on by the transbuccal-transclival approach is reported. The authors remark on the intraoperative use of endoscopy for a better removal of the turnout. Initial clinical improvement persists after one year. * T u m b i o l o , A., ** S o r r e n t i n o , G., * M o r e l l o , A., ** P e l l e g r i n o , S. (* D i v i s i o n o f N e u r o s u r g e r y a n d ** D i v i s i o n o f O t o r h i n o l a r i n g o l o g y , Ospedale Civico, Palermo): Nystagmus Retractorius in Post-

Traumatic Comatose Patients. Three cases of nystagmus retractorius were observed in comatose patients after head injury. In the two cases who had favourable courses the nystagmus disappeared when the level of consciousness became normal. On the contrary, in the third case, it did not disappear until the time of death.

Proceedings of the 26th annual meeting of the Società Italiana di Neurochirurgia 24-26 November 1977, Rome, Italy. Abstracts.

Abstracts of the 16th Annual Meeting of the American Society of Neuroradiology 1978.

Proceedings of the British Cardiac Society. 20-21 November 1978. Abstracts.

Proceedings of the Anatomical Society of Great Britain and Ireland. November 1978. Abstracts.

Abstracts of the EAO 23rd Annual Scientific Meeting, September 25-27, 2014, Rome, Italy.

Abstracts of the 4th Annual Meeting, Frontiers in Neurology, November 21, 2014, Dublin, Ireland.

Abstracts of the Hong Kong Urological Association Annual Scientific Meeting, November 9, 2014, Hong Kong.

Abstracts of the Fourth Annual Meeting of the Associazione Italiana Sistema Nervoso Periferico, April 13–15, 2014, Sorrento (Na), Italy.

Abstracts of the 3rd Annual Meeting, Frontiers in Neurology, 15 November 2013, Dublin, Ireland.

The American Society for Cell Biology 32nd annual meeting. November 15-19, 1992, Denver, Colorado. Abstracts.

Abstracts from the ASENT 18th Annual Meeting.

Heberden Society clinical meeting, June 1978. Abstracts.

Paediatric Pathology Society. Proceedings of the Twenty-fourth Annual Meeting: Abstracts.

Abstracts of the 48th Annual Scientific Meeting of the Vascular Society of Great Britain and Ireland, 27–29 November 2013.

Scottish Paediatric Society. Annual general meeting, 17 November 1978. Scientific communications.

Pancreatic Society of Great Britain and Ireland. 14th annual meeting. 17 November 1989. Abstracts.

2015 ASCB Annual Meeting abstracts.

Proceedings of the British Medical Ultrasound Society. 22nd annual meeting. Harrogate, December 4-6, 1990. Abstracts.

Abstracts of the 41st Annual Meeting of the Austrian Diabetes Society. November 21-23, 2013. Salzburg, Austria.

Abstracts of the 2013 Annual Scientific Meeting of the Irish Thoracic Society (ITS). November 15-16, 2013. Derry, Ireland.

ASGCT 19th Annual Meeting: Abstracts.

Abstracts of the 49th Annual Scientific Meeting of the Vascular Society of Great Britain and Ireland, November 26-28, 2015.

Society for Pediatric Radiology abstracts: 1978 meeting.

Abstracts of the 16th Annual Meeting of the Israel Society for Neuroscience, November 25-27, 2007, Eilat, Israel.