J Neurosurg 48:450-454, 1978
Spontaneous healing of intraeranial aneurysms after subarachnoid hemorrhage Case report
GORAN EDNER, MEO. LIe., DAVID M . C. FOnSTEn, F.R.C.S., LADISLAU STEINER, M.D., AND ULF BERGVALL, MED. LIC.
Departments of Neurosurgery and Neuroradiology, Stockholm, Sweden
Karolinska Sjukhuset,
v" A case of spontaneous intra-aneurysmal thrombosis, verified angiographically, is reported in a patient with subarachnoid hemorrhage and without surgical intervention. The frequency of such an occurrence and the factors involved are reviewed and discussed. KEY WORDS intracraniai aneurysm 9 subarachnoid hemorrhage 9 cerebral angiography 9 spontaneous thrombosis 9 antifibrinolytic drugs 9
EW cases of complete spontaneous thrombosis verified during life have been reported in the medical literature in patients with subarachnoid hemorrhage (SAH). Recently, in this clinic, we managed a patient whose anterior communicating artery (ACoA) aneurysm failed to fill with contrast material at a second preoperative angiogram 17 days after SAH. The case is presented here, and the literature is reviewed. The question of the frequency of such an occurrence, the factors that might favor such an event, and the permanence of such a thrombosis are discussed.
F
Case Report
This 26-year-old woman was admitted 3 days after SAH, at the onset of which she had briefly lost consciousness. On admission, there was neck stiffness but no focal neurological signs; she was normotensive and in good general health. The 450
cerebrospinal fluid was bloody, and the supernatant xanthochromic. There was no significant family history, but for several years she had been taking an oral contraceptive regularly (at the time of admission, Neovlar 21"). Four days after SAH, a single saccular aneurysm, 10 • 8 • 8 mm in size, arising from the ACoA was demonstrated at fourvessel cerebral angiography (Fig. 1 upper left) using rapid serial angiography and Isopaque (meglumine and calcium metrizoates). There was no evidence of vasospasm or hematoma. In addition to bed rest, she was given epsilonaminocaproic acid (EACA), 30 gm intravenously per day for the first 4 days, then 36 gm daily by mouth. During the next few days the patient became drowsier and developed papilledema, with 2 diopters of protrusion. Repeat spinal *Each capsule of Neovlar 21 contains 0.25 mg D-Norgestrel, and 50 mg aethinyl aestradiol. J. Neurosurg. / Volume 48 / March, 1978
Spontaneous healing of intracranial aneurysms
FIG. 1. Right internal carotid angiography with compression (subtraction) 4 days (upper left), 17 days (upper right), 3 months (lower left), and 14 months (lower right) after SAH. The aneurysm (arrow) is clearly seen on Day 4 but is not visible on the subsequent angiograms.
tap showed no sign of rebleeding and the deterioration was attributed to vasospasm. She was given dexamethasone (Decadron), 16 mg daily, and her condition gradually improved. Right carotid angiography was repeated 17 days after SAH (Fig. 1 upper right). Unexpectedly there was no filling of the aneurysm, despite adequate communication across the ACoA on cross-compression of the carotid artery. Severe arterial spasm was widespread. There was no evidence of progressive ventricular dilatation, with a ventriculocranial index TM unchanged at 0.31. The patient's condition continued to improve slowly; dexamethasone and EACA were gradually reduced in dose and discontinued by the 24th day. The papilledema gradually subsided after the introduction of acetazolamide (Diamox), 20 mg/kg/day, and furosemide (Lasix), 40 mg daily, on the 24th day. The patient was discharged home 6 weeks after the hemorrhage. She remained well, and after 5 months returned to her previous occupation as a social worker. To ensure that there was still no filling of the aneurysm, right carotid angiography with cross-compression was repeated twice more,
J. Neurosurg. / Volume 48 / March, 1978
3 months and 14 months after SAH (Fig. 1 lower). On both occasions, contrast filling of the ACoA was adequate, but on neither occasion was there any filli~agof the aneurysm. No ventricular dilatation developed. The patient remains well 3 years after SAH. Discussion
It was suggested by Dandy, TM in 1944, that perhaps as many as 15% of patients with SAH due to ruptured intracranial aneurysms may be healed by spontaneous thrombosis of the aneurysms. This estimate has been supported by some autopsy studies. For example, Crompton 7 reported complete thrombosis in 21 of 166 patients (13%) who died without surgical interference, and Housepian and Pool ~2 reported 10 similar instances among 113 patients (9%). In both series the incidence was smaller in patients whose aneurysms had not bled. On the other hand, Krayenb~ihl found only one totally thrombosed aneurysm in a series of 7452 autopsies? e The high incidence of complete thrombosis that was found at autopsy has not been encountered during life. At the Karolinska Hospital between 1964 and 1973, rapid serial 45'1
G. Edner, D. M. C. Forster, L. Steiner and U. Bergvall cerebral angiography was repeated, without intervening surgery, in 78 patients (84 aneurysms) with SAH, at intervals varying from 2 days to 8 years. Twelve aneurysms had increased in size, six were smaller although there was no vasospasm, the one reported in this article had disappeared, and the remaining were unchanged. From our experience, it seems unlikely that more than 1% or 2% of ruptured intracranial arterial aneurysms will spontaneously thrombose completely. Furthermore, such a thrombosis must be complete to provide a cure, and the fact that partially thrombosed aneurysms may rebleed is well d o c u m e n t e d ) A review of the literature has revealed only six cases in which complete thrombosis of an intracranial arterial aneurysm has been established during life following SAH, without surgical interference with the aneurysm or its parent artery, locally or in the neck. 19,23,27,28 In these six cases, an aneurysm was demonstrated radiologically following SAH, but failed to fill with contrast medium when angiography of the appropriate vessel was repeated after intervals ranging from a few weeks to several years. We have omitted cases in which the artery feeding the ruptured aneurysm did not opacify during the repeat a n g i o g r a p h y because of gross spasm obliterating the feeding artery or a failing circulation in a moribund patient. 17,3~,37 T h e s p o n t a n e o u s disappearance of a number of aneurysms of mycotic origin has been satisfactorily established by a few a u t h o r s ? ,5,",25,39 It is easy to imagine the process by which i n f l a m m a t i o n of the aneurysm wall might lead to thrombosis and r_pair. A similar process combined with partial narrowing of the aneurysmal neck may a c c o u n t for the c o m p l e t e occlusion encountered in cases where craniotomy has been performed and the aneurysm dissected but not completely ligated or clipped. 2,4,~1,~5 Similarly, the gradual obliteration of an aneurysm treated by stereotaxic radiosurgery may occur by the same process? s It is also well d o c u m e n t e d that an aneurysm may diminish in size or completely fail to fill with contrast material after partial or complete temporary or permanent intracranial or extracranial occlusion of the principal feeding artery? '8,~2a~,~8,4~ Logically, attempts have been made to promote thrombosis in berry aneurysms by 452
combining a n t i f i b r i n o l y t i c therapy with regionally retarded circulation and controlled hypotension. Khil'ko and Shkliarova ~4 reported successful thrombosis in six of nine cases with saccular aneurysms arising from the internal carotid, but no case of complete thrombosis with an A C o A aneurysm. Mullan a~ reported the combined use of partial carotid ligation, hypotensive medication, and antifibrinolytic therapy in 15 patients with bleeding berry aneurysms, while awaiting the optimum time for operation. No information was given regarding the radiological appearance of the aneurysms at the time of intracranial surgery. In the present case, when angiography on the 17th day after S A H showed no filling of the a n e u r y s m , it was not considered justifiable to expose the patient to the risks of intracranial surgery. The factors leading to the occlusion remain uncertain. Antifibrinolytic therapy and the previous use of oral contraception may have had an influence, although the effect of the latter on coagulation and fibrinolysis in vitro are conflicting. 6,~~ I f the failure of the aneurysm to fill with contrast material was due to blood clot, 33 such a clot might recanalize, and rebleeding occur? T M As Mullan and his coworkers have pointed out, the blood clot that seals the initial aneurysmal hemorrhage seems clinically to have a very short life, as does the clot initiated artificially with an electric current. 29,31 Only time will indicate the degree of permanence of the thrombosis in the present case and the correctness of the decision to defer surgery, which was contrary to the decision to operate in the case reported by H 5 5 k and Norl6n. 23 It is clear from this review that the spontaneous thrombosis of ruptured intracranial arterial aneurysms without intervention is rare and too infrequent for the outcome in the cases in which it does occur to be predicted with confidence.
References 1. Barker WF: Mycotic aneurysms. Ann Surg 139:84-89, 1954 2. af Bj6rkesten G, Troupp H: Changes in the size of intracranial arterial aneurysms. J Neurosurg 19:583-588, 1962 3. Black SPW, German W J: Observations on the relationship between the volume and the size J. Neurosurg. / Volume 48 / March. 1978
Spontaneous healing of intraeranial aneurysms
4.
5.
6. 7.
8.
9.
10. 1I.
12.
13. 14.
15.
16.
17.
of the orifice of experimental aneurysms. J Neurosurg 17:984-990, 1960 Bonnal J, Stevenaert A: Thrombosis of intracranial aneurysms of the circle of Willis after incomplete obliteration by clip or ligature across the neck. J Neurosurg 30:158-164, 1969 Cantu RC, LeMay ML, Wilkinson HA: The importance of repeated angiography in the treatment of mycotic-embolic intracranial aneurysms. J Neurosurg 25:189-193, 1966 Caspary EA, Peberdy M: Oral contraception and blood-platelet adhesiveness. Lancet 1:1142-1143, 1965 Crompton MR: Recurrent haemorrhage from cerebral aneurysms and its prevention by surgery. J Neurol Neurosurg Psychiatry 29: 164-170, 1966 Cronqvist S, Lundberg M, Troupp H: Temporary or incomplete occlusion of the carotid artery in the neck for the treatment of intracranial arterial aneurysms. Neurochirurgia 7:146-151, 1964 Crawford T: Some observations on the pathogenesis and natural history of intracranial aneurysms. J Neurol Neurosurg Psychiatry 22:259-266, 1959 Dandy WE: Intracranial Arterial Aneurysms. Ithaca, NY: Comstock Publishing, 1944, pp 1-22 Devadiga KV, Mathai KV, Chandy J: Spontaneous cure of intracavernous aneurysm of the internal carotid artery in a 14-month-old child. Case report. J Neurosurg 30:165-168, 1969 Drake CG: Ligation of the vertebral (unilateral or bilateral) or basitar artery in the treatment of large intracranial aneurysms. J Neurosurg 43:255-274, 1975 Drake CG, Allcock JM: Postoperative angiography and the "slipped" clip. J Neurosurg 39:683-689, 1973 Drake CG, Vanderlinden RG: The late consequences of incomplete surgical treatment of cerebral aneurysms. J Neurosurg 27:226-238, 1967 Durity F, Logue V: The effect of proximal anterior cerebral occlusion on anterior communicating artery aneurysms. Postoperative radiological survey of 43 cases. J Neurosurg 35:16-19, 1971 Ecker AD, Riemenschneider PA: Deliberate thrombosis of intracranial arterial aneurysm by partial occlusion of the carotid artery with arteriographic control. Preliminary report of a case. J Neurosurg 8:348-353, 1951 Epstein BS: The roentgenographic aspects of thrombosis of aneurysms of the anterior communicating and anterior cerebral arteries. Am
J Roentgenol Radium Ther Nucl Med 70: 211-217, 1953
J. Neurosurg. / Volume 48 / March, 1978
18. Galera R, Greitz TVB: Hydrocephalus in the adult secondary to the rupture of intracranial arterial aneurysms. J Neurosurg 32:634-641, 1970 19. Hemmer R, Umbach W: Verlaufsformen intrakranieller sackfSrmiger Aneurysmen. Arch Psychiatr Nervenkr 200:612-625, 1960 20. Hilden M, Amris C J, Starup J: The haemostatic mechanism in oral contraception. Aeta Obstet Gynecol Stand 46:562-571, 1967 21. Hollin SA, Gross SW: Changing size of an aneurysm. Report of a case. J Neurosurg 24:573-575, 1966 22. Housepian EM, Pool JL: A systematic analysis of intracranial aneurysms from the autopsy file of the Presbyterian Hospital, 1914 to 1956. J Neuropathol Exp Neurol 17: 409-423, 1958 23. H65k O, Norl6n G: Aneurysms of the middle cerebral artery. A report of 80 cases. Acta Chir Stand (Suppl 235):1-39, 1958 24. Khil'ko VA, Shkliarova ED: [Artificial formation of clots in arterial aneurysms with the aid of epsilon-aminocaproic acid and other coagulants against the background of regionally retarded circulation.] Vopr Neirokhir 33:6-11, 1969 (Rus) 25. Kowada M, Takahashi M, Gito Y: Spontaneous cure of intracranial aneurysm. Case report. Acta Neurochir 31:131-137, 1974 26. Krayenb/ihl H: Das Hirnaneurysma. Schweiz Arch Neurol Psyehiatr 47:155-236, 1944 27. Lodin H: Spontaneous thrombosis of cerebral aneurysms. Case reports. Br J Radiol 39:701-703, 1966 28. Marguth F, Schiefer W: Spontanheilung eines intrakraniellen Aneurysms angiographisch nachgewiesen. Acta Neurochir 5:38--45, 1957 29. Mullan S: Conservative management of the recently ruptured aneurysm. Surg Neurol 3:27-32, 1975 30. Mullan S: Experiences with surgical thrombosis of intracranial berry aneurysms and carotid cavernous fistulas. J Neurosurg 41: 657-670, 1974 31. Mullan S, Beckman F, Vailati G, et al: An experimental approach to the problem of cerebral aneurysm. J Neurosurg 21:838-845, 1964 32. Mullan S, Dawley J: Antifibrinolytic therapy for intracranial aneurysms. J Neurosurg 28: 21-23, 1968 33. Nizzoli V, Lechi A: Emorragie subaracnoidee spontanee con reperto angiografico negitivo. Sist Nerv 16:82-103, 1964 34. Poller L, Thomson JM: Clotting factors during oral contraception: further report. Br Meal J 2:23-25, 1966 35. Sato S, Suzuki J: Prognosis in cases of intracranial aneurysm after incomplete direct 453
G. Edner, D. M. C. Forster, L. Steiner and U. Bergvall operations. Acta Neurochir 24:245-252, 1971 36. Scott RM, Garrido E: Spontaneous thrombosis of an intracranial aneurysm during treatment with epsilon aminocaproic acid. Surg Neuroi 7:21-23, 1977 37. Spetzler RF, Winestock D, Newton HT, et al: Disappearance and reappearance of cerebral aneurysm in serial arteriograms. Case report. J Neurosurg 41:508-510, 1974 38. Steiner L, Leksell L, Forster DMC, et al: Stereotactic radiosurgery in intracranial arterio-venous malformations. Aeta Neuroehir (Suppl) 21:195-209, 1974 39. Suwanwela C, Suwanwela N, Charuchinda S, et al: Intracranial mycotic aneurysms of extravascular origin. J Neurosurg 36:552-559, 1972
454
40. Tindall GT, Goree JA, Lee JF, et al: Effect of common carotid ligation on size of internal carotid aneurysms and distal intracarotid and retinal artery pressure. J Neurosurg 25: 503-511, 1966 41. Ygge J, Brody S, Korsan-Bengtsen K, et al: Changes in blood coagulation and fibrinolysis in women receiving oral contraceptives. Comparison between treated and untreated women in a longitudinal study. Am J Obstet Gyneeol 104:87-98, 1969
Address reprint requests to: David M. C. Forster, F.R.C.S., The Royal Infirmary, Sheffield, $6 3DA, England.
J. Neurosurg. / Volume 48 / March, 1978
Spontaneous healing of intraeranial aneurysms after subarachnoid hemorrhage Case report
GORAN EDNER, MEO. LIe., DAVID M . C. FOnSTEn, F.R.C.S., LADISLAU STEINER, M.D., AND ULF BERGVALL, MED. LIC.
Departments of Neurosurgery and Neuroradiology, Stockholm, Sweden
Karolinska Sjukhuset,
v" A case of spontaneous intra-aneurysmal thrombosis, verified angiographically, is reported in a patient with subarachnoid hemorrhage and without surgical intervention. The frequency of such an occurrence and the factors involved are reviewed and discussed. KEY WORDS intracraniai aneurysm 9 subarachnoid hemorrhage 9 cerebral angiography 9 spontaneous thrombosis 9 antifibrinolytic drugs 9
EW cases of complete spontaneous thrombosis verified during life have been reported in the medical literature in patients with subarachnoid hemorrhage (SAH). Recently, in this clinic, we managed a patient whose anterior communicating artery (ACoA) aneurysm failed to fill with contrast material at a second preoperative angiogram 17 days after SAH. The case is presented here, and the literature is reviewed. The question of the frequency of such an occurrence, the factors that might favor such an event, and the permanence of such a thrombosis are discussed.
F
Case Report
This 26-year-old woman was admitted 3 days after SAH, at the onset of which she had briefly lost consciousness. On admission, there was neck stiffness but no focal neurological signs; she was normotensive and in good general health. The 450
cerebrospinal fluid was bloody, and the supernatant xanthochromic. There was no significant family history, but for several years she had been taking an oral contraceptive regularly (at the time of admission, Neovlar 21"). Four days after SAH, a single saccular aneurysm, 10 • 8 • 8 mm in size, arising from the ACoA was demonstrated at fourvessel cerebral angiography (Fig. 1 upper left) using rapid serial angiography and Isopaque (meglumine and calcium metrizoates). There was no evidence of vasospasm or hematoma. In addition to bed rest, she was given epsilonaminocaproic acid (EACA), 30 gm intravenously per day for the first 4 days, then 36 gm daily by mouth. During the next few days the patient became drowsier and developed papilledema, with 2 diopters of protrusion. Repeat spinal *Each capsule of Neovlar 21 contains 0.25 mg D-Norgestrel, and 50 mg aethinyl aestradiol. J. Neurosurg. / Volume 48 / March, 1978
Spontaneous healing of intracranial aneurysms
FIG. 1. Right internal carotid angiography with compression (subtraction) 4 days (upper left), 17 days (upper right), 3 months (lower left), and 14 months (lower right) after SAH. The aneurysm (arrow) is clearly seen on Day 4 but is not visible on the subsequent angiograms.
tap showed no sign of rebleeding and the deterioration was attributed to vasospasm. She was given dexamethasone (Decadron), 16 mg daily, and her condition gradually improved. Right carotid angiography was repeated 17 days after SAH (Fig. 1 upper right). Unexpectedly there was no filling of the aneurysm, despite adequate communication across the ACoA on cross-compression of the carotid artery. Severe arterial spasm was widespread. There was no evidence of progressive ventricular dilatation, with a ventriculocranial index TM unchanged at 0.31. The patient's condition continued to improve slowly; dexamethasone and EACA were gradually reduced in dose and discontinued by the 24th day. The papilledema gradually subsided after the introduction of acetazolamide (Diamox), 20 mg/kg/day, and furosemide (Lasix), 40 mg daily, on the 24th day. The patient was discharged home 6 weeks after the hemorrhage. She remained well, and after 5 months returned to her previous occupation as a social worker. To ensure that there was still no filling of the aneurysm, right carotid angiography with cross-compression was repeated twice more,
J. Neurosurg. / Volume 48 / March, 1978
3 months and 14 months after SAH (Fig. 1 lower). On both occasions, contrast filling of the ACoA was adequate, but on neither occasion was there any filli~agof the aneurysm. No ventricular dilatation developed. The patient remains well 3 years after SAH. Discussion
It was suggested by Dandy, TM in 1944, that perhaps as many as 15% of patients with SAH due to ruptured intracranial aneurysms may be healed by spontaneous thrombosis of the aneurysms. This estimate has been supported by some autopsy studies. For example, Crompton 7 reported complete thrombosis in 21 of 166 patients (13%) who died without surgical interference, and Housepian and Pool ~2 reported 10 similar instances among 113 patients (9%). In both series the incidence was smaller in patients whose aneurysms had not bled. On the other hand, Krayenb~ihl found only one totally thrombosed aneurysm in a series of 7452 autopsies? e The high incidence of complete thrombosis that was found at autopsy has not been encountered during life. At the Karolinska Hospital between 1964 and 1973, rapid serial 45'1
G. Edner, D. M. C. Forster, L. Steiner and U. Bergvall cerebral angiography was repeated, without intervening surgery, in 78 patients (84 aneurysms) with SAH, at intervals varying from 2 days to 8 years. Twelve aneurysms had increased in size, six were smaller although there was no vasospasm, the one reported in this article had disappeared, and the remaining were unchanged. From our experience, it seems unlikely that more than 1% or 2% of ruptured intracranial arterial aneurysms will spontaneously thrombose completely. Furthermore, such a thrombosis must be complete to provide a cure, and the fact that partially thrombosed aneurysms may rebleed is well d o c u m e n t e d ) A review of the literature has revealed only six cases in which complete thrombosis of an intracranial arterial aneurysm has been established during life following SAH, without surgical interference with the aneurysm or its parent artery, locally or in the neck. 19,23,27,28 In these six cases, an aneurysm was demonstrated radiologically following SAH, but failed to fill with contrast medium when angiography of the appropriate vessel was repeated after intervals ranging from a few weeks to several years. We have omitted cases in which the artery feeding the ruptured aneurysm did not opacify during the repeat a n g i o g r a p h y because of gross spasm obliterating the feeding artery or a failing circulation in a moribund patient. 17,3~,37 T h e s p o n t a n e o u s disappearance of a number of aneurysms of mycotic origin has been satisfactorily established by a few a u t h o r s ? ,5,",25,39 It is easy to imagine the process by which i n f l a m m a t i o n of the aneurysm wall might lead to thrombosis and r_pair. A similar process combined with partial narrowing of the aneurysmal neck may a c c o u n t for the c o m p l e t e occlusion encountered in cases where craniotomy has been performed and the aneurysm dissected but not completely ligated or clipped. 2,4,~1,~5 Similarly, the gradual obliteration of an aneurysm treated by stereotaxic radiosurgery may occur by the same process? s It is also well d o c u m e n t e d that an aneurysm may diminish in size or completely fail to fill with contrast material after partial or complete temporary or permanent intracranial or extracranial occlusion of the principal feeding artery? '8,~2a~,~8,4~ Logically, attempts have been made to promote thrombosis in berry aneurysms by 452
combining a n t i f i b r i n o l y t i c therapy with regionally retarded circulation and controlled hypotension. Khil'ko and Shkliarova ~4 reported successful thrombosis in six of nine cases with saccular aneurysms arising from the internal carotid, but no case of complete thrombosis with an A C o A aneurysm. Mullan a~ reported the combined use of partial carotid ligation, hypotensive medication, and antifibrinolytic therapy in 15 patients with bleeding berry aneurysms, while awaiting the optimum time for operation. No information was given regarding the radiological appearance of the aneurysms at the time of intracranial surgery. In the present case, when angiography on the 17th day after S A H showed no filling of the a n e u r y s m , it was not considered justifiable to expose the patient to the risks of intracranial surgery. The factors leading to the occlusion remain uncertain. Antifibrinolytic therapy and the previous use of oral contraception may have had an influence, although the effect of the latter on coagulation and fibrinolysis in vitro are conflicting. 6,~~ I f the failure of the aneurysm to fill with contrast material was due to blood clot, 33 such a clot might recanalize, and rebleeding occur? T M As Mullan and his coworkers have pointed out, the blood clot that seals the initial aneurysmal hemorrhage seems clinically to have a very short life, as does the clot initiated artificially with an electric current. 29,31 Only time will indicate the degree of permanence of the thrombosis in the present case and the correctness of the decision to defer surgery, which was contrary to the decision to operate in the case reported by H 5 5 k and Norl6n. 23 It is clear from this review that the spontaneous thrombosis of ruptured intracranial arterial aneurysms without intervention is rare and too infrequent for the outcome in the cases in which it does occur to be predicted with confidence.
References 1. Barker WF: Mycotic aneurysms. Ann Surg 139:84-89, 1954 2. af Bj6rkesten G, Troupp H: Changes in the size of intracranial arterial aneurysms. J Neurosurg 19:583-588, 1962 3. Black SPW, German W J: Observations on the relationship between the volume and the size J. Neurosurg. / Volume 48 / March. 1978
Spontaneous healing of intraeranial aneurysms
4.
5.
6. 7.
8.
9.
10. 1I.
12.
13. 14.
15.
16.
17.
of the orifice of experimental aneurysms. J Neurosurg 17:984-990, 1960 Bonnal J, Stevenaert A: Thrombosis of intracranial aneurysms of the circle of Willis after incomplete obliteration by clip or ligature across the neck. J Neurosurg 30:158-164, 1969 Cantu RC, LeMay ML, Wilkinson HA: The importance of repeated angiography in the treatment of mycotic-embolic intracranial aneurysms. J Neurosurg 25:189-193, 1966 Caspary EA, Peberdy M: Oral contraception and blood-platelet adhesiveness. Lancet 1:1142-1143, 1965 Crompton MR: Recurrent haemorrhage from cerebral aneurysms and its prevention by surgery. J Neurol Neurosurg Psychiatry 29: 164-170, 1966 Cronqvist S, Lundberg M, Troupp H: Temporary or incomplete occlusion of the carotid artery in the neck for the treatment of intracranial arterial aneurysms. Neurochirurgia 7:146-151, 1964 Crawford T: Some observations on the pathogenesis and natural history of intracranial aneurysms. J Neurol Neurosurg Psychiatry 22:259-266, 1959 Dandy WE: Intracranial Arterial Aneurysms. Ithaca, NY: Comstock Publishing, 1944, pp 1-22 Devadiga KV, Mathai KV, Chandy J: Spontaneous cure of intracavernous aneurysm of the internal carotid artery in a 14-month-old child. Case report. J Neurosurg 30:165-168, 1969 Drake CG: Ligation of the vertebral (unilateral or bilateral) or basitar artery in the treatment of large intracranial aneurysms. J Neurosurg 43:255-274, 1975 Drake CG, Allcock JM: Postoperative angiography and the "slipped" clip. J Neurosurg 39:683-689, 1973 Drake CG, Vanderlinden RG: The late consequences of incomplete surgical treatment of cerebral aneurysms. J Neurosurg 27:226-238, 1967 Durity F, Logue V: The effect of proximal anterior cerebral occlusion on anterior communicating artery aneurysms. Postoperative radiological survey of 43 cases. J Neurosurg 35:16-19, 1971 Ecker AD, Riemenschneider PA: Deliberate thrombosis of intracranial arterial aneurysm by partial occlusion of the carotid artery with arteriographic control. Preliminary report of a case. J Neurosurg 8:348-353, 1951 Epstein BS: The roentgenographic aspects of thrombosis of aneurysms of the anterior communicating and anterior cerebral arteries. Am
J Roentgenol Radium Ther Nucl Med 70: 211-217, 1953
J. Neurosurg. / Volume 48 / March, 1978
18. Galera R, Greitz TVB: Hydrocephalus in the adult secondary to the rupture of intracranial arterial aneurysms. J Neurosurg 32:634-641, 1970 19. Hemmer R, Umbach W: Verlaufsformen intrakranieller sackfSrmiger Aneurysmen. Arch Psychiatr Nervenkr 200:612-625, 1960 20. Hilden M, Amris C J, Starup J: The haemostatic mechanism in oral contraception. Aeta Obstet Gynecol Stand 46:562-571, 1967 21. Hollin SA, Gross SW: Changing size of an aneurysm. Report of a case. J Neurosurg 24:573-575, 1966 22. Housepian EM, Pool JL: A systematic analysis of intracranial aneurysms from the autopsy file of the Presbyterian Hospital, 1914 to 1956. J Neuropathol Exp Neurol 17: 409-423, 1958 23. H65k O, Norl6n G: Aneurysms of the middle cerebral artery. A report of 80 cases. Acta Chir Stand (Suppl 235):1-39, 1958 24. Khil'ko VA, Shkliarova ED: [Artificial formation of clots in arterial aneurysms with the aid of epsilon-aminocaproic acid and other coagulants against the background of regionally retarded circulation.] Vopr Neirokhir 33:6-11, 1969 (Rus) 25. Kowada M, Takahashi M, Gito Y: Spontaneous cure of intracranial aneurysm. Case report. Acta Neurochir 31:131-137, 1974 26. Krayenb/ihl H: Das Hirnaneurysma. Schweiz Arch Neurol Psyehiatr 47:155-236, 1944 27. Lodin H: Spontaneous thrombosis of cerebral aneurysms. Case reports. Br J Radiol 39:701-703, 1966 28. Marguth F, Schiefer W: Spontanheilung eines intrakraniellen Aneurysms angiographisch nachgewiesen. Acta Neurochir 5:38--45, 1957 29. Mullan S: Conservative management of the recently ruptured aneurysm. Surg Neurol 3:27-32, 1975 30. Mullan S: Experiences with surgical thrombosis of intracranial berry aneurysms and carotid cavernous fistulas. J Neurosurg 41: 657-670, 1974 31. Mullan S, Beckman F, Vailati G, et al: An experimental approach to the problem of cerebral aneurysm. J Neurosurg 21:838-845, 1964 32. Mullan S, Dawley J: Antifibrinolytic therapy for intracranial aneurysms. J Neurosurg 28: 21-23, 1968 33. Nizzoli V, Lechi A: Emorragie subaracnoidee spontanee con reperto angiografico negitivo. Sist Nerv 16:82-103, 1964 34. Poller L, Thomson JM: Clotting factors during oral contraception: further report. Br Meal J 2:23-25, 1966 35. Sato S, Suzuki J: Prognosis in cases of intracranial aneurysm after incomplete direct 453
G. Edner, D. M. C. Forster, L. Steiner and U. Bergvall operations. Acta Neurochir 24:245-252, 1971 36. Scott RM, Garrido E: Spontaneous thrombosis of an intracranial aneurysm during treatment with epsilon aminocaproic acid. Surg Neuroi 7:21-23, 1977 37. Spetzler RF, Winestock D, Newton HT, et al: Disappearance and reappearance of cerebral aneurysm in serial arteriograms. Case report. J Neurosurg 41:508-510, 1974 38. Steiner L, Leksell L, Forster DMC, et al: Stereotactic radiosurgery in intracranial arterio-venous malformations. Aeta Neuroehir (Suppl) 21:195-209, 1974 39. Suwanwela C, Suwanwela N, Charuchinda S, et al: Intracranial mycotic aneurysms of extravascular origin. J Neurosurg 36:552-559, 1972
454
40. Tindall GT, Goree JA, Lee JF, et al: Effect of common carotid ligation on size of internal carotid aneurysms and distal intracarotid and retinal artery pressure. J Neurosurg 25: 503-511, 1966 41. Ygge J, Brody S, Korsan-Bengtsen K, et al: Changes in blood coagulation and fibrinolysis in women receiving oral contraceptives. Comparison between treated and untreated women in a longitudinal study. Am J Obstet Gyneeol 104:87-98, 1969
Address reprint requests to: David M. C. Forster, F.R.C.S., The Royal Infirmary, Sheffield, $6 3DA, England.
J. Neurosurg. / Volume 48 / March, 1978
