MUCOCELES OF THE SPHENOID SINUS: NEURO-OPHTHALMOLOGIC MANIFESTATIONS* BY Melvin G. Alper, MD INTRODUCTION

MUCOCELES OCCUR LESS OFTEN IN THE SPHENOID SINUS THAN IN THE OTHER

paranasal sinuses. Since their first description by Berg' in 1889, preoperative or ante mortem diagnosis was rarely established until recent years. Delayed diagnosis in the past often led to severe visual loss while misdiagnosis resulted in exploratory craniotomy for pituitary tumor with disastrous consequences. Nugent and associates2 recentLy reviewed the world literature finding 81 cases, reporting 63 of these and adding 2 of their own. Isolated case histories have appeared since this review so that approximately 100 cases of sphenoid sinus mucoceles have been reported to date. 3-10 Since many of these patients are first seen because of eye complaints, it is important for the ophthalmologist to be aware of the ocular manifestations. With an increased index of clinical suspicion and the use of presently available sophisticated neuroradiologic techniques, early diagnosis and proper management should become more common in the future. This paper will report seven additional cases of sphenoid sinus mucocele with ocular findings varying from isolated ocular motor nerve palsies to total blindness. The diagnostic neuroradiologic features will be presented, and the proper management will be described. PATHOLOGY

Although some doubt exists concerning the etiology, mucoceles in general have been divided into primary and secondary types (Table *From the Department of Ophthalmology, Washington Hospital Center, D. C. TR. AM. OPHTH. Soc., vol. LXXIV, 1976

Washington,

54 TABLE I: CLASSIFrCATION OF MUCOCELES

I. Primary Types A. Retention cysts arise from mucous glands of sinus epithelium. II. Secondary Types A. Due to obstruction of sinus ostia. B. Arise from cystic degeneration of sinus polyps.

I). Primary types arise from retention cysts of the mucous glands of the sinus epithelium. Secondary types arise either from obstruction of the sinus osteum or from cystic degeneration of sinus polyps.13 This process precludes normal drainage of the sinus and leads to a dilated cavity filled with a thick dark or sometimes clear fluid. They may be unilateral or bilateral. Ciliated columnar cells of the sphenoid sinus are replaced by cuboidal cells or layers of pigment cells. The mucocele wall is composed of fibrous connective tissue with round cell infiltration. 14 Because of their relationship to many vital structures, sphenoid sinus mucoceles can cause a wide variety of symptoms and signs de-

FIGURE 1

Coronal diagram demonstrating relationship of the sphenoid sinus to surrounding vital structures. Arrows indicate pathways of extension of sphenoid sinus mucoceles encountered in this series of seven patients.

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FIGURE 2

Lateral diagram illustrating routes of extension of mucoceles of the sphenoid sinus. Mucoceles may extend upward eroding the bone of the sella floor to press against the pituitary gland and chiasm simulating an intrasellar adenoma. More often, extension is anterior against the ethmoid cells, which offer little resistance, and thence to the orbital apices. Displacement of the cavernous portion of the carotid artery commonly occurs from lateral and upward extension. Involvement of the cranial nerves III, IV, VI and V (first and second division) comes from lateral extension. Erosion of the clivus posteriorly simulates chordomas. Inferior extension into the nasopharynx with erosion of the palatine bone is another route of extension.

pending upon which adjacent structure is involved by the expanding cyst. Because the posterior ethmoidal cells offer the least resistant barrier to erosion, pressure from the expanding sphenoidal sinus is primarily transmitted to this area and thus to the apices of the orbit, causing headache and visual symptoms (Fig. 1 and 2). The sphenoid sinus itself lies in the body of the sphenoid bone usually incompletely divided by a midline septum. Anteriorly, the sphenoid sinus abuts the posterior ethmoid air sinus and cribiform plate and forms part of the posterior upper nasopharyngeal wall where it drains by two ostia into the nasopharynx. Posteriorly, it is located in front of and under the sella turcica. Inferiorly, it is bounded by the nasopharynx and the pterygoid fossa. Laterally, the sphenoid sinus is bounded posteriorly by the cavernous sinuses and internal carotid arteries, while anteriorly it is separated from the optic canal by a bony

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wall 0.5 mm thick. The volume of the sphenoid sinus can vary from 0.05 to 14.0 cc. The structures that surround the sphenoid sinus include the first six cranial nerves, the internal carotid arteries, the cavernous sinuses, the tuberculum sellae, the sella turcica, the anterior and posterior clinoids, the planum sphenoidale, the pituitary gland, the optic canals, the medial walls of the superior orbital fissures and the orbit, and the clivus posteriorly. CASE REPORTS CASE 1

A 23-year-old white women, was seen on January 2, 1969, with a chief complaint of severe headache behind her left eye associated with double vision and drooping of the left upper lid for 24 hours duration. Three weeks before the onset of the present illness she had had flu and had been confined to bed for one week. For two weeks prior to the onset of the present illness she had had a full sensation in her head with stuffy ears and a dull ache behind her left eye. Twenty-four hours before the onset of her present illness the pain behind her left eye became intense. She awakened with double vision and drooping of her left upper lid. The pain behind her left eye was characterized as being more intense in the supine position and somewhat alleviated when assuming the erect position. A review of systems revealed menarche at age 11 years. The menses were regular, occurring every thirty days for four to five days duration until 18 months before the present illness. At that time they became irregular and were characterized by heavy flooding every two to three months with amenorrhea in the interim. Seven years prior to the onset of the present illness she developed a great gain in weight, reaching a body weight of 278 lbs. Her energy was said to be normal but there was a loss of libido. The vision of the right eye was 20/20 and the left eye was 20/20 with best correction. There was an external third nerve paralysis of the left eye (Fig. 3); pupillary reflexes were normal in both eyes. The anterior segments of each eye were within normal limits. The optic nerve and retina were normal in each eye. Visual fields by Goldmann perimeter as well as by tangent screen revealed a bitemporal hemianopia to small test targets but there were full fields to large test targets. Applanation tension in each eye was 14 mm mercury. The neurological evaluation was within normal limits except for the above described third nerve palsy. She appeared to be an obese, well developed, well nourished white female in no acute distress. Her blood pressure was 160/ 100. Her heart and lungs were normal. The remainder of the physical examination was non-revealing. There was a normal blood count and urinalysis. Her blood sugar was 77 mg/ 100 ml; urea nitrogen, 6 mg/100 ml; sodium, 137.5 mEq; potassium, 3.7 mEq; chloride, 95 mEq; cortisol, 6.5 mEq per 100 ml (normal 7 to 27). Glucose

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FIGURE 4

Postoperative photograph of patient in Figure 3 demonstrating recovery of the left third nerve following sphenoidectomy and sinusotomy.

tolerance test showed the following: fasting, 82 mg/100 ml; one-half hour, 138 mg/100 ml; one hour, 138 mg/100 ml; two hours, 120 mg/100 ml; three hours, 108 mg/100 ml. Tests for urine sugar and acetone were negative in all of these collections. The urine 17 ketosteroids measured 12.3 mg per twenty-four hours; the 17 hydroxysteroids, 6.4 mg per twenty-four hours (17 ketosteroids normal for females: 7 to 13; 17 hydroxysteroids normal for females: 2.7). Twentyfour hour urine gonadotropin (FSH) was less than eight rat units per twentyfour hour urine specimen. (Normal reproductive range for females is 8 to 30 rat units per twenty-four hour urine specimen.) Serum protein electrophoresis was within normal limits. Cerebrospinal fluid evaluation: protein 18.3 mg/ 100 ml; 19 lymphocytes; sugar 50 mg/100 ml; chlorides 120 mg/100 ml; the Kolmer and colloidal gold were normal. Serum protein electrophoresis of the spinal fluid protein was within normal limits. Iodine-131 thyroid uptake after twenty-four hours, 15.7% (normal euthyroid range 16 to 30%). T 3 was 36.1% (normal range 27 to 38%). Urine creatinine measured 1,618 mg per twenty-four hours. On the second hospital day the patient spiked a fever to 103 F. Blood cultures showed a twenty-four hour gram negative Hemophilus influenzae bacillus which was sensitive to ampicillin, chloramphenicol, colistine, erythromycin, canomycin, neomycin, penicillin, streptomycin and tetracycline. The urine cultured Escherichia coli and Staphylococcus epidermis. Ampicillin and streptomycin were given. Her fever returned to normal and the blood culture was reported as negative after 48 hours. The sella appeared to be enlarged on normal skull films, but with tomography the sella turcica floor was well demonstrated and there was a mass measuring 1 X 4 cm in the

FIGURE

5

A: Lateral roentgenogram of skull (Case 1), showing enlargement and distention of the sphenoid sinus. White and black arrow demonstrates partial destruction of sella turcica floor. Two small arrows show involvement of the clivus. A nasopharyngogram has been performed. Single black arrow demonstrates protrusion of soft tissue mass into the roof and posterior wall of the nasopharynx. B: Modified waters view of paranasal sinus (Case 1). Black arrow indicates lateral displacement of left lamina papyracea.

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FIGURE 6

Brachial arteriogram (Case 1) demonstrates lateral displacement of the cavernous portion of the internal carotid artery in the AP view (A), and upward displacement with some arterial narrowing in the lateral view (B). Normally, the cavernous portion of the internal carotid artery bows inward in contradistinction to the outward bowing deformity noted in A.

sphenoid sinus. The posterior clinoid was destroyed in its lower part. There was partial destruction of the clivus and some of the bony floor of the sella. Protrusion of a soft tissue mass 1 cm in diameter into the roof and posterior wall of the nasopharynx was also noted with destruction of the left posterior clinoic, left dorsum sellae and left anterior clinoid. Nasopharyngograms demonstrated the nasopharyngeal lesion to good advantage. Brachial arteriography with filling of both internal carotids revealed lateral and upward displacement of the portion of the internal carotid artery lying within the carvernous sinus (Fig. 6). Pneumoencephalography demonstrated no abnormalities of the ventricular system. A chest roentgenogram was within normal limits. Scintiscan utilizing technetium 99 failed to demonstrate any definite abnormality in the brain. The preoperative impression was that of a mucocele of the sphenoid sinus although a pituitary tumor such as chromophobe adenoma or a chordoma of the clivus could not be excluded. On the twenty-second hospital day a submucous resection of the nasal septum and transnasal removal of a mass from the sphenoid sinus was performed under general anesthesia. The sinus was filled with a thick cheesy white material which was mostly suctioned out and cultured. The entire sac lining the sphenoid sinus was carefully removed and the sinus cleansed of its debris. Two small ureteral catheters were placed in the sinus and sutured to the nasal vestibule for drainage. Culture of the material from the sphepoid sinus revealed Haemophilus influenzae. The microscopic diagnosis of the tissue removed from the sphenoid sinus was interpreted as a pyomucocele.

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FIGURE 7

Preoperative photographs (Case 2) demonstrating right third nerve paralysis and loss of light reflex in both eyes (A, B, C, D). A right third nerve paralysis and blindness was noted on admission to hospital with left upper quadrantanopia. Following a spontaneous convulsion while undergoing a brain scan, the patient became blind in the left eye. Atrophy ensued in both the right (E) and left (F) optic nerves, although the third nerve paralysis recovered.

Twenty-four hours following evacuation of the material from the sphenoid sinus the patient regained normal function of the third nerve. In the year following the operation the patient lost 55 pounds without change in her diet. Her menses became regular and the cortisol levels returned to normal. Follicular stimulating hormone, which had been less than eight rat units for twentyfour hour urine specimen preoperatively returned to more normal limits postoperatively measuring 16 units per twenty-four hour unit specimen. Her visual fields returned to normal in forty-eight hours.

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FIGURE 8

Cerebral flow study (Case 2) performed with Tc-99m-pertechnetate demonstrating decreased activity in the right internal carotid artery (one arrowhead) when compared to the left (two arrowheads).

The patient has remained well and her endocrine abnormalities have disappeared. CASE 2

A 24-year-old black man was admitted to the hospital on July 17, 1972 with a history of severely progressive headache for eight days which was generalized in character with some preponderance for localization in the right supraorbital area. Four days before admission he became nauseated without vomiting. The headache was unremitting and was not relieved by analgesics. Three days before admission he awoke with increased pain and ptosis of the right upper lid. There was an associated blurring of the vision in the right eye. He was seen in the emergency room where the problem was felt to be migraine and he was referred to an evening "walk in" clinic. At the "walk in" clinic he was given fiorinal and an appointment was made for thorough evaluation one week later. Three days later he was seen in the emergency room because of unrelieved headache which had increased in severity and had now become associated with a complete ptosis of the right upper lid (Fig. 7). He was referred immediately to the eye clinic where it was determined that the right eye was blind. The vision in the left eye was 20/200 and there was a complete third

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FIGURE 9

Lateral roentgenogram of skull (Case 2) demonstrating destruction of sella floor (arrow) with preservation of the dorsum and anterior clinoid process. Haziness is present in the inferior portion of the expanded sphenoid sinus.

nerve paralysis present on the right side. In addition, a confrontation visual field revealed an upper temporal defect in the left eye. On admission to the hospital on July 17, 1972, the physical examination revealed a well developed, well nourished, 24-year-old black man in no acute distress. Except for the abovenoted abnormalities which had been observed in the eye clinic, he was neurologically intact. The differential diagnosis at that time was aneurysm of the internal carotid artery, superior orbital fissure syndrome, a parasellar cavernous sinus lesion, or pituitary apoplexy. Skull roentgenograms were obtained and a complete destruction of the sella turcica with preservation of the dorsum and anterior clinoid processes was revealed. The roof of the sphenoid sinus was not visualized. These findings were borne out on tomography of the sphenoid and sella area. He was immediately sent to the nuclear medicine department for cerebral blood flow and brain scan. During the flow studies there was abnormal cerebral perfusion with definite but decreased counts from the right hemisphere when compared to the left. Symmetry, however, was rapidly obtained. There was no evidence of an aneurysm during the flow study. While in the nuclear medicine department he had a spontaneous convulsion following which he was blind in the left eye. The brain scan itself was within normal limits and no mass lesion was noted. He was next sent immediately to the neuroradiology section where a right brachial arteriogram showed normal filling of the vertebral-basilar artery system with

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X

FIGURE

^

^

10

Selective right transfemoral carotid angiography in Case 2 shows total obstruction of the right internal carotid artery at its cavernous portion on lateral view (A) (arrow) and outward bowing on AP view (B) (arrow).

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:4.......4........

~~~~~~~~~~~~~~~~~~~~~~~~~~~..:.'.;.:'. A Preopera>.tiv :.+8.: abora ceeba flow s$tud (Case 2). B:.:

Normal postoperative flow study. Despite recovery of a normal cerebral blood flow postoperatively, the patient remained blind in both eyes', but recovered from the right third nerve

paralysis.

delayed flow into the right carotid system (Fig. 10). There was reflux filling of the left carotid by passage of the dye via the intra-cavernous and supra-cavernous portions which indicated obstruction of the right carotid artery. A right transfemoral angiogram was then performed with selective right carotid arteriography demonstrating a normal common carotid up to the bifurcation where there was delayed flow through the internal carotid and total obstruction at the level of the anterior clinoid. There was also lateral displacement of the cavernous portion of the internal carotid artery and no filling of any intracranial branch above the siphon. A percutaneous left carotid arteriogram was then performed and the cavernous portion showed its normal inward bowing in contrast to that of the right internal carotid artery. Neuroradiological impression at this time was obstruction of the right internal a very

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carotid artery at the level of the anterior clinoid with lateral displacement of the cavernous portion. It was felt that there was an intrinsic lesion in the region of the sella and sphenoid sinus most likely arising from a lesion of the sphenoid sinus itself. The patient's status at this time was that of blindness in both eyes with a complete third nerve paralysis on the right side, but he was otherwise neurologically intact. All other laboratory studies were normal. His blood count was within normal limits and there was a normal differential white blood cell count. The ear, nose and throat service was consulted. A transpalatal sphenoidectomy was performed with evacuation of a huge sphenoid sinus pyomucocele. Alpha hemolytic streptococcus was cultured and proved to be sensitive to ampicillin, which was instituted. After this treatment, there was no recovery of the postoperative visual acuity, although the third nerve paralysis in the right eye improved. He was discharged one week after admission, blind in both eyes with a recovering right third nerve paralysis. He was readmitted six days later with a hemorrhage from the palatal incision which had dehisced. Five hundred cc of whole blood were given on admission and he was taken to the operating room where another 500 cc of whole blood were administered. The bleeding area in the palate was resutured and hemostasis obtained. The postoperative course was subsequently uneventful and he was discharged four days after admission. He subsequently developed serum hepatitis which recovered without incident. When last seen, he was blind in both eyes and the third nerve paralysis had completely recovered. CASE 3

A 50-year-old black man was admitted to the hospital on November 5, 1970 with a two month history of progressively severe headache, worse in the supine position than in the erect position. In the days just prior to admission it had become so severe that he could not sleep. One week prior to admission he had developed diplopia. The remainder of his history was unrevealing. Examination of his eyes revealed vision in the right eye to be 20/20, vision in the left eye to be 20/20; the visual fields were normal; intraocular pressure by applanation was 15 mm of Hg in each eye. Slit lamp examination was normal. Ophthalmoscopy was normal. Bilateral sixth nerve paralysis was present (Fig. 12). He was otherwise intact neurologically. Skull roentgenograms were obtained and revealed an increased lucency in the sphenoid sinus with thinning of the clivus. Polytomography revealed the clivus to be eroded in its major portion. The floor of the sphenoid sinus was also eroded with a soft tissue mass extending into the epipharynx. The floor of the sella turcica was normal. Cerebral blood flow and brain scan revealed an asymmetry in the posterior view of the left side below the tentorium adjacent to the midline. On lateral views, there was some asymmetry in the region of the posterior fossa, more diffusely increased on the left than on the right. Transfemoral selective arteriography was performed. The left veretebral artery was normal as was the basilar artery. Selective injection into the left common carotid artery showed lateral displacement of the internal carotid at the level of the cavernous sinus. In

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FIGURE 12

Photograph (Case 3) demonstrating bilateral abducens nerve paralysis. Primary position (A). Gaze right (B). Gaze left (C).

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FIGURE 13

Pneumoencephalogram (Case 3) demonstrates air along the clivus (arrow) which is thinned. The air extends into the pre-pontine system normally with no masses demonstrated. The sella floor is intact and the sphenoid sinus is expanded.

addition, the artery was slightly elevated. A fractional pneumoencephalogram revealed air along the clivus in the pre-pontine system and its lateral extension with no masses into the prepontine system (Fig. 13). The third and fourth ventricle as well as the aqueduct and lateral ventricles were not well visualized although the chiasmal portion of third ventricle was seen to be normal. All other laboratory studies were within normal limits. A transeptal sphenoidectomy and sinusotomy was performed on November 19, 1970. Tissue from the sphenoid sinus was obtained for biopsy and for culture. The tissue of the sphenoid sinus was interpreted as acute and chronic sinusitis and Staphylococcus epidermidis was cultured. This was sensitive to ampicillin, chloramphenicol, erythromycin, canomycin, cephalothin, linococin, penicillin and streptomycin. The sinus was drained and the patient was placed on antibiotics. The headache was relieved but there was no improvement in the bilateral sixth nerve paralysis. Because of persistent bilateral abducens nerve paralysis, he was readmitted one month later and a biopsy was obtained from the nasopharynx. A transitional cell carcinoma was discovered. He was given radiation and chemotherapy without relief of the bilateral abducens nerve paralysis. In July, 1971 he developed bronchopneumonia and expired on July 6, 1971. Autopsy revealed transitional cell carcinoma of the naso-

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pharynx and base of the skull invading the sphenoid sinus, the clivus, and other areas along the base of the skull; bronchopneumonia; and retention cysts of the kidney. Death was attributed to the bronchopneumonia. CASE 4

A 33-year-old black woman was well until seven months before admission on April 25, 1967, when she developed increasingly severe headaches which were accentuated in the supine position and often awakened her in the middle of the night. After assuming the erect position the headaches gradually subsided. In the immediate weeks prior to admission the headaches became so severe that she was confined to bed with constant throbbing pain localized to the vertex and occiput, unrelieved by common analgesics. Three weeks prior to admission she had developed horizontal diplopia in association with the severe pain in her head. Two months previously she had been examined by her otolaryngologist and treated in his office for sphenoid sinusitis without relief of her symptoms. With onset of diplopia she was referred to a local ophthalmologist who observed an uncorrected vision of 20/20 in each eye, and a concomitant, nonaccommodative esotropia of 16 prism diopters for both distance and 14 inches. Orthophoria was present at 4 inches and moderate exophoria at 2 inches. The remainder of the ocular examination was normal and intraocular pressure measured 15 mm/Hg by applanation tonometry in each eye. The ophthalmogist felt that this was a divergence paralysis and not a bilateral sixth nerve palsy.

Because of the possibility that this was a supranuclear paralysis of divergence with mid-brain disease, the patient was hospitalized on April 25, 1967 on the neurosurgical service. The admission examination revealed a well developed, well nourished black woman of stated age in apparent pain but no acute distress. The resident noted a left lateral rectus muscle palsy on admission as well as an apparent weakness of divergence at distance. Her pupils appeared equal and reacted normally to light and accommodation. Apparently the extraocular motility had changed from the previous evaluation by the ophthalmologist and she now displayed a definite left lateral rectus muscle paralysis. In addition there was loss of sense of smell and taste and some weakness of the left side of the face of a peripheral type facial nerve paresis. The laboratory evaluation was essentially within normal limits. The blood count was normal with a normal differential. Cerebrospinal fluid revealed normal opening pressure and 38 mg/100 ml protein with no cells. Cultures of the cerebrospinal fluid and urine were normal. Routine roentgenograms of the skull including tomograms revealed that the sella turcica was normal in size and configuration without intra- or parasellar calcification. There was a mass or bony density adjacent to the mid-portion of the clivus as seen in the lateral projection and this mass appeared to encroach upon the sphenoid sinus posteriorly suggesting either a chordoma or a meningioma. The radiolucency in the mid-portion of the clivus measured about 2.5 cm and the sphenoid sinus appeared to be continuous with this radiolucency.

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A brain scan failed to reveal any abnormality. A right retrograde brachial arteriogram was performed on May 10, 1967 and showed good visualization of the basilar artery in a normal position without displacement from the clivus. The transverse sinus in the posterior fossa and the jugular vein revealed no abnormalities. The cavernous portion of the right internal carotid was slightly bowed laterally and a similar abnormality was noted in the left internal carotid cavernous portion. A fractional pneumoencephalogram revealed no abnormalities. These findings pointed to the possibility of a sphenoid sinus mass eroding the clivus but not displacing any neural structures. On June 2, 1967 a submucous resection and transeptal sphenoid sinusotomy with biopsy of the sphenoid mucosa and insertion of a cannula were performed. Creamy yellow mucopurulent material under slight pressure was obtained upon entry into the sphenoid sinus. There was no tumor within the sphenoid that was visible. A ureteral catheter No. 5 was inserted into the sphenoid sinus for drainage. The mucopurulent material cultured Staphylococcus epidermidis and proved sensitive to penicillin. The patient had an unremarkable recovery, the diplopia subsided, the headache disappeared and she was discharged asymptomatic. When last seen in November 1967, she remained asymptomatic. CASE 5

A 58-year-old white woman was hospitalized on February 25, 1971 because of severe right sided headache which had become progressive in intensity for five to six weeks prior to admission. The pain originated in the right occipitofrontal area and extended to the right retrobulbar area becoming most intense behind the right eye. For many years she had had vague right sided headaches prior to the onset of the present illness and there had been some difficulty in breathing from the right nostril. There were no other associated visual or neurologic complaints. Examination on admission revealed the vision in each eye to be 20/20 with best correction. The external examination, slit lamp examination, and ophthalmoscopy were normal. Intraocular pressure was 15 mm Hg by applanation tonometry. Visual fields were full. Her general physical examination revealed a well developed, well nourished white female in no apparent distress with blood pressure 140/80. Except for a moderately deviated nasal septum to the right her physical examination was noncontributory. Routine skull roentgenograms demonstrated opacification of the right sphenoid sinus. Tomograms showed erosion of the sphenoid plate. Echoencephalogram, electroencephalogram, and brain scan were normal. All other laboratory evaluations were normal. The impression was mucopyocele of the sphenoid sinus. On March 3, 1971 a transeptal sphenoid sinusotomy was performed. The sinus was noted to be filled with thick mucopurulent material. A culture revealed Proteus mirabilis. The pathologic report was chronic hyperplastic sinusitis of the sphenoid sinus. A French No. 5 ureteral catheter had been inserted into the sinus for drainage and the patient was discharged from the

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hospital on March 8, 1971, asymptomatic. When last seen she had remained free of her headaches and retrobulbar pain. CASE 6

A 12-year-old black boy was admitted to the Washington Hospital Center on January 6, 1976 with two months history of headaches accentuated in the supine position. Two weeks prior to admission he had fallen and skull roentgenograms were performed because of minor head trauma. The sphenoid sinus was noted to be enlarged. Polytomography denoted no bony destruction. The past medical history revealed that in 1973 he had undergone a nasal polypectomy in another hospital. On admission the patient appeared to be a well developed, well nourished twelve year old boy in no obvious distress. A physical examination was essentially normal except for deviation of the nasal septum to the right and polypoid degeneration of the nasal mucosa. Ophthalmological consultation revealed vision in each eye to be 20/20. There was an alternating exotropia of 16 prism diopters at distance and near with convergence insufficiency. Visual fields were full. Intraocular pressure was 13 mm Hg by applanation tonometry in each eye. Ophthalmoscopy was negative. A minimal degree of myopia was present. Routine laboratory studies were within normal limits. A skull roentgenogram revealed a soft tissue mass with sharp margins arising from the floor of the sphenoid sinus which itself was enlarged. The mass measured 2 cm in diameter and there was no evidence of bony destruction. On January 7, 1976 a transnasal sphenotomy was performed under roentgen ray control. Cultures were taken and revealed Staphylococcus epidermidis and alpha hemolytic Streptococcus not group D, both of which were sensitive to penicillin. Mucosa revealed chronic inflammation consistent with sphenoid sinus mucopyocele. A ureteral catheter No. 4 was placed in the previously empty sphenoid sinus and the patient was discharged on the sixth postoperative day. He has remained asymptomatic since discharge and when last seen was relieved of his headaches. CASE 7

A 42-year-old white male physician was hospitalized on December 18, 1963 with a 6-week history of unremitting left side headache. It was associated with left ptosis and was aggravated by sneezing or coughing, drinking whiskey or smoking tobacco, and when assuming a supine position. It was relieved by aspirin or eating. Antibodies did not relieve the condition. Physical examination including neurological evaluation was non-revealing except for the left ptosis. The vision in each eye was 20/20 without correction. There was ptosis on the left upper lid. The pupils were equal and reacted well to light and accommodation. Visual fields were full to all test targets. Cocaine chemodiagnostic testing for Horner's syndrome was negative. Urinalysis, complete blood count, EEG, and brain scan were normal. Lumbar puncture demonstrated an opening pressure of 175 mm Hg. All studies of the cerebrospinal fluid were normal and smears and cultures for tubercle

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bacillus and fungi were negative. Blood studies were within normal limits. Protein-bound iodine (PBI) was 8.9 ,g/100 ml (normal 4 - 8). Serology was negative. Roentgenograms of the skull, including laminography, revealed a defect in the floor of the sella turcica and an abnormal shadow in the sphenoid sinus. The differential diagnosis included pituitary tumor invading the sphenoid sinus or some pathologic process arising in the sphenoid sinus and secondarily destroying the floor of the sella turcica. A mucocele of the sphenoid sinus was considered. Left ptosis associated with left-sided headache was suggestive of Raeder's paratrigeminal neuralgia, but Horner's syndrome was absent. On January 15, 1964, a turbinectomy of the middle turbinate was performed and the sphenoid sinus explored by direct inspection. The sinus was felt to be normal by the surgeon. Following this procedure, headaches were relieved but ptosis persisted. After two weeks, the headache returned and Dr. John Bordley of Johns Hopkins Hospital was asked to see the patient in consultation. He has kindly made his records available. When the patient was seen by Dr. Bordley, he had developed a left external ophthalmoplegia, involving the third and sixth nerves. Because of the erosion of the sella floor, pituitary tumor was considered in the differential diagnosis. A total rhinotomy was performed which allowed exposure of the sphenoid as well as the extradural approach to the pituitary should this be necessary. Following drainage of a mucopyocele of the sphenoid sinus, the patient was relieved of his symptoms and a follow-up roentgenogram revealed regeneration of the bone of the sella turcica floor. The patient remains well to this time. He reported that on April 21, 1976, he had had no more headaches and that the ptosis had completely cleared.

CLINICAL FINDINGS

The most common presenting symptom was headache, usually severe and chronic, either constant or intermittent, and more intense in the supine position (Table II). The headache was often retrobulbar in character, many times frontotemporal in nature and occasionally occurred in the occipitovertex. The headache was usually relieved on assuming an erect position. In case 7, the headache was associated with ptosis and aggravated by drinking alcohol. These symptoms were suggestive of Raeder's trigeminal neuralgia although Horner's syndrome was absent. Diplopia was a common symptom due to either third or sixth nerve palsy (cases 1, 2, 3, 4). Loss of vision progressing to total blindness and bilateral optic atrophy occurred in one patient (case 2). Visual field defects of a bitemporal nature were noted in two patients (cases 1 and 2). Severe endocrine disturbance was noted in one patient and was relieved after successful treatment of the mucocele (case 1).

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TABLE II: CLINICAL FINDINGS IN 7 PATIENTS WITH SPHENOID MUCOCELES

Number of Cases

Percent

Symptoms

Headache Loss of vision Diplopia Otolaryngologic history Endocrine disturbances

7 1 4 3 1

100 14.28 57.14 42.85 14.28

Signs

External ophthalmoplegia 5 71.42 IIIrd nerve 3 42.85 VIth nerve 3 42.85 Ptosis 1 14.28 Optic atrophy 1 14.28 Studies Visual field loss 2 28.57 Enlarged sphenoid sinus 7 100 Bone erosion 6 85.71 Clivus involvement 3 42.85 Sella turcica destruction 3 42.85 Carotid artery displacement of angiography* 4 57.14 *Cerebral angiography was performed on only 4 patients, so that 100% abnormalities occurred in these our.

One patient (case 3) revealed a transitional cell carcinoma of the nasopharynx with involvement of the base of the skull which probably resulted in occlusion of the sphenoid sinus drainage, causing a secondary type of obstructive mucopyocele. Enlargement of the sphenoid sinus was present in all seven patients. Erosion of bone was a common finding on roentgen ray examination (cases 1, 2, 3, 4, 5, 7) and involved most of the surrounding bony structures. The sella turcica was destroyed in 3 cases (1, 2, 7) and the clivus was also involved in 3 instances (2, 3, 4). The optic canal was spared in this series. All four patients who underwent cerebral angiography had lateral bowing of one or both internal carotid arteries in the cavernous portion. The second patient (case 2) had an occlusion of the right internal carotid artery at the anterior aspect of the siphon. DIAGNOSIS

Diagnosis is made on the basis of roentgen ray evaluation. Any dense opacification of the sphenoid sinus with expanded or destroyed osseous walls in association with a widened superior orbital fissure, eroded optic canal, elevated anterior clinoid and planum sphenoidale, lateral dis-

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placement of the lamina papyracea, or sella turcica floor destruction, should suggest the diagnosis of sphenoid sinus mucocele. 11'12'14"15 Special studies should include hypocycloidal polytomography, which is useful in delineating the extent and nature of the anatomical change; computerized assisted tomography to determine intracranial extension; carotid arteriography which characteristically shows displacement of the internal carotid artery; and, in some cases, pneumoencephalography which may be necessary to determine chiasmal involvement or to rule out disease of the clivus. 18"19 DIFFERENTIAL DIAGNOSIS

Differential diagnosis includes a whole host of syndromes and lesions including the following: (1) ophthalmoplegic migraine, (2) internal carotid artery aneurysms, (3) hypophyseal tumors, (4) nasopharyngeal tumors, (5) craniopharyngioma, (6) tumor of the sphenoid sinus and/or posterior ethmoid cells, (7) meningioma, (8) glioma, (9) cholesteatoma, (10) chordoma, (11) adamantanoma, (12) base of the skull tumors, (13) pneumosinus dilitans, and (14) sphenoid fissure syndrome. TREATMENT

The treatment of choice of sphenoid mucoceles is rhinologic surgery. 16 Our otolaryingologic consultant prefers transnasal sphenoidectomy to remove the diseased mucous membranes and sinusotomy with adequate drainage maintained by some form of indwelling drain.17 Ureteral catheters placed under roentgen ray control into the sinus and sutured into position have been utilized for this purpose. One of the patients (case 7) underwent surgery at Johns Hopkins Hospital. A total rhinotomy with exposure of the sphenoid through the septum was performed which allowed visualization of the entire sphenoid cavity as well as an extradural view of the pituitary fossa.20 It is not within the scope of this report to describe in detail the various surgical techniques, but it is the author's conviction that transcranial approaches are contraindicated because they are too hazardous. Appropriate antibiotic control is also important and should be continued as indicated. DISCUSSION

The seven patients presented characterize the neuro-ophthalmologic findings in sphenoid sinus mucoceles. Our findings are very similar

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to those of McCarthy and others who summarized the clinical findings described by Nugent and colleagues and those from the recent literature. 8 In our patients headache was the most common symptom, and was characteristically accentuated in the supine position. It was relieved when the upright position was assumed. It could well be explained on the basis of irritation of the gasserian ganglion or the first two branches of the trigeminal nerve by expansion against these structures in the supine position. It could also be explained by reason of upward stretching of the planum sphenoidal and floor of the anterior cranial fossa or by posterior pressure against the clivus. Ophthalmoplegia is explained on the basis of lateral extension involving the cranial nerves as they pass through the cavernous sinus. Case 3 presented a diagnostic puzzle which was solved only with passage of time. A secondary type of mucocele probably developed due to obstruction of the nasopharyngeal ostia by transitional cell carcinoma. The fact that headache was relieved following drainage of the sphenoid sinus indicates that distention of the sinus itself contributed to this symptom. Diagnosis of nasopharyngeal carcinoma is difficult in most instances. In this patient, the appearance of a sphenoid sinus mucocele masked the true diagnosis for a period of time because we attributed all of the symptoms to the mucocele. Failure of recovery from bilateral abducens nerve paralysis, however, led to biopsy of the nasopharynx. This established the diagnosis and pointed to invasion of these cranial nerves by the tumor as the cause for paralysis. Autopsy eventually proved these findings. Pituitary tumor was considered in the differential diagnosis of cases 1, 2 and 7. Chromophobe adenoma was suspected in Case 1 because of bitemporal hemianopia, endocrine change, and headache. Pituitary apoplexy was considered in Case 2 because of headache and sudden blindness associated with destruction of the sella turcica. Headache and destruction of the sella floor in one patient (Case 7) also pointed to pituitary involvement. Although it is possible to compress the optic nerve by extension towards the optic canal, the most likely explanation for blindness which occurred in case 2 was by reason of embarrassment of the blood supply due to lateral extension against the intracavernous portion of the internal carotid artery. In fact, this latter phenomenon was well demonstrated both by cerebral blood flow on radionuclide scanning and by arteriography. The radionuclide cerebral blood flow demonstrated a definite embarrassment of blood supply to the right side and was confirmed

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Alper by arteriography which revealed occlusion of the internal carotid above the syphon. Following a convulsion while undergoing a brain scan, the patient became totally blind in his left eye. Although we were unable to demonstrate embarrassment of blood supply on this side by either arteriography or radionuclide cerebral blood flow one must consider the possibility of a vascular occlusion because of the precipitous nature of the blindness. Doyle and Simeon7 reported the only case in the literature thus far of internal carotid artery occlusion. Their patient had angiographic evidence of bilateral carotid artery occlusion but fortunately blindness did not ensue due to collateral circulation from the vertebrobasilar system. However, there was marked optic atrophy in the right eye of their patient following sphenoid sinusotomy. The endocrine disturbance noted in one patient (Case 1) characterized by severe weight gain, amenorrhea, and lowered cortisol levels is quite unusual. Very few cases have been reported in the literature with this phenomenon. It is interesting to note that the patient had a marked weight loss and return of normal menses following relief of her mucopyocele of the sphenoid sinus. To date we have been unfortunate in not having obtained computerized assisted tomographic evidence of sphenoid sinus mucoceles, so that we do not have an example to demonstrate the characteristic findings by this new non-invasive technique. Despite this, with the use of hypocycloidal polytomography and angiography we feel that the diagnosis can readily be made once the condition is suspected. Delay in reaching a proper diagnosis before treatment was instituted in one patient (Case 2) could well have attributed to the ensuing blindness. A high index of suspicion is necessary, in order to perform the proper sequence of diagnostic investigations, as was well demonstrated in the cases herein reported. SUMMARY

Seven examples of mucocele of the sphenoid sinus have been described. The characteristic symptoms and signs have been described, and the diagnostic neuroradiologic features have been demonstrated. The condition is not a benign one, as is demonstrated by total blindness which occurred in one patient (Case 2). A high index of suspicion for this condition with early referral for neuroradiologic diagnosis leads to proper management and treatment which is usually successful.

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REFERENCES 1. Berg J: Bidrag till kannedomen om sjirkdomarna i nasans bihalor samt till laran om cerebro-spinal-vatskas flytning ur nasam. Nord Med Ark 21:1-24, 1889. 2. Nugent GR, Sprinkle P, Bloor BM: Sphenoid sinus mucoceles. J Neurosurg 32:443 1970. 3. Stanton MB: Sphenoid sinus mucocele. Am J Ophthalmol 70:991, 1970. 4. Friedmann G, Harrison S: Mucocele of the sphenoidal sinus as a cause of recurrent oculomotor nerve palsy. J Neurol Neurosurg Psychiatry 33:172, 1970. 5. Ghosh P, Desmond AF: Sphenoidal mucocele. J Laryngol Otol 84:1073, 1970. 6. Simms NM, Brown WE, French LA: Mucocele of the sphenoid sinus presenting as an intrasellar mass. J Neurosurg 32:708, 1970. 7. Doyle CS, Simeon FA: Mucocele of the sphenoid sinus with bilateral internal carotid artery occlusion. J Neurosurg 36:351, 1972. 8. McCarthy WJ Jr, Frenkel M, Busse BJ: Visual loss as the only symptom of sphenoid sinus mucocele. Am J Ophthalmol 74:1134, 1972. 9. Kuhns TR: Diplopia and optic atrophy in a 59-year-old man. Presented at the Fourth Annual Neuro-Ophthalmologic Pathology Symposium, Northwestern Univ., Chicago, Feb. 1972. 10. Krueger TP, McFarland J, Ommaya AK: Pyocele of the sphenoid sinus. J Neurosurg 22:616-621, 1965. 11. Bloom DL: Mucoceles of the maxillary and sphenoid sinus. Radiology 85:11031110, 1965. 12. James AE Jr: Destroyed sphenoidal sinus. JAMA 206:2732-2733, 1968. 13. Brown JM, Goodhill V: In I Coates GM, Schenck P and Miller NV (eds): Otolaryngology, Vol. 3, Hagerstown, Maryland, WF Prior, 1956, Chap. 15, pp 15-17. 14. Palubinskas AJ, Davies H: Roentgen features of nasal accessory sinus mucoceles. Radiology 72:576-584, 1959. 15. Valvassori GE, Putterman AM: Ophthalmologic and roentgenographic findings in sphenoidal mucoceles. Trans Am Acad Ophthalmol Otolaryngol 77:703-713, 1973. 16. Maisel RH, Deeb ME, Bone RC: Sphenoid sinus mucoceles. Laryngoscope 83:930939, 1973. 17. Trible Wm: Personal Communication. 18. Takahashi M, Jingu K, Nakayama T: Roentgenologic appearances of sphenoethmoidal mucocele. Neuroradiology 6:45-49, 1973. 19. Minagi H, Margolis MT, Newton TH: Tomography in the diagnosis of sphenoid sinus mucocele. Am J Roentgenol Radium Ther Nucl Med 115:587-591, 1972. 20. Bordley J: Personal communication.

DISCUSSION

DR DAVID 0. HARRINGTON. I have read Dr Alper's paper with great interest and profit. I will have only good things to say about it in this discussion. I believe that Dr Alper's most important conclusion is that one must have a high index of suspicion for this condition in order to avoid the often disastrous results of misdiagnosis or delay in diagnosis. He points out that the diagnosis is made on the basis of roentgenographic evaluation and it is interesting to note that only four of his nineteen references are in ophthalmic journals. The majority of reports of this condition are found in journals of radiology and neurosurgery. It is also noteworthy that the most elegant and sophisticated roentgenographic techniques were necessary to establish the diagnosis.

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The difficulties in differential diagnosis are manifested in the author's list of fourteen possible conditions which may simulate a sphenoid sinus mucocele. In the absence of clear cut roentgenographic evidence of sphenoid sinus disease it may still be possible to establish the diagnosis on clinical findings alone. Direct chiasmal pressure with interference with its blood supply may produce bitemporal hemianopic visual field defects. A more frequent finding is an irregular scotomatous defect due to pressure and ischemic infarction in the optic nerve. This may also give rise to altitudinal hemianopia, either monocular or binocular. In years past it was common practice to open and drain the ethmoid and sphenoid sinuses in almost every case of papillitis or retrobulbar neuritis with central scotomatous field defects. The rhinologist often reported a swollen and congested sinus but rarely uncovered a muco-pyocele. Many of these cases demonstrated prompt and dramatic improvement in their visual loss and their scotomas rapidly disappeared. It is presently popular to scoff at this form of treatment for optic neuritis but it seems quite possible that the drainage of a suspect sphenoid sinus may prevent the development of a true mucocele and lead to the happy results that Dr Alper has so well documented when early and adequate rhinologic surgery is instituted. In the event that it is quite impossible to decide between a diagnosis of pituitary adenoma and sphenoidal mucocele the surgical approach should be by the transsphenoidal route. If no mucocele is encountered a hypophysectomy may then be accomplished via the same route. I agree that a transcranial approach is extremely hazardous if a mucocele is present. Dr Alper is to be congratulated on this presentation. It again calls to our attention a potentially very serious disease which, when recognized, is amenable to treatment. Dr Alper's case reports are models of completeness and deserve careful study. DR THOMAS HEDGES. I want to congratulate Doctor Alper on his presentation and show three slides which illustrate again the importance of recognizing the consistent pain that the slower onset type patient will develop behind his eyes with a sphenoid sinus mucocele. This type of pain is consistent with many of these pathologic phenomena within the cavernous sinus. This young man had optic atrophy and hemichromatopsia and was thought to have had a chromophobe adenoma. On the arteriogram, you will see that he had complete occlusion of both carotid arteries by compression of the mucocele. He was one of the first patients that I had seen with a transsphenoidal approach through the sphenoidal sinus which has now become so valuable in the treatment of pituitary tumors. His symptoms were immediately relieved. He had a typical large "balloon" sella illustrating the ideal patient (whether he has a pituitary lesion or a sphenoid sinus mucocele) who should now be operated upon through the sphenoidal sinus. This brachial arteriogram shows the vessels that are coming into the orbit. They are coming there through the posterior circulation, and as you can see, through the other route through the external maxillary artery.

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There is a spectrum from the slow onset that this boy demonstrates to the apoplexic type. The latter are really neurosurgical emergencies. Again, congratulations to Dr Alper for a fine paper. DR THOMAS P. KEARNS. I, too, would like to congratulate Doctor Alper on his first meeting and his first paper. At the risk of being accused of bringing CAT fever to these lovely islands, I felt compelled to step forward. For those of you who don't know what CAT fever is and those who have not read the recent article in the New England Journal of Medicine, let me define CAT fever. It is the feverish impulse to own, operate, exploit or write about what has been known as computerized axial tomography (CAT) but has been renamed computed tomography (N Eng J Med 294: 954-956, 1976). I'm surprised that Dr Alper did not have some CAT scans as I hear they also have CAT fever in Washington. Doctor Pang tells me that CAT fever has already reached Honolulu and I am sure it will soon spread throughout the islands. May we have that first slide please? This is the new 320 matrix EMI-Scan that we are using at our institution. For those who might not be familiar with CAT scans, the first matrix was an 80 x 80. The present one and the one that is used most often now is 160 x 160. This slide shows the total body scanner which is a 320 matrix. Not only does it give you better definition, that is higher resolution, but as you can see you can fit the patient's head in much easier. With the previous EMI-Scan the patient had to have a small head or you couldn't see the orbits. Here you see we're scanning not only the orbits but even below the orbits. Look at this nice sphenoid sinus. There is no mucocele here. I have not as yet seen a mucocele since we have been using our 320 matrix EMI-Scan. You can see the nasal cavity here, the maxillary sinus here, and this is the sphenoid sinus. Here is another EMI-Scan showing the nasal septum, the sphenoid sinus, and the brain tissue here. Here is another EMIScan of a patient who does have a nasopharyngeal tumor. This is not a mucocele or a pyocele but this is a neurolemmoma in the nasopharynx. Here are the teeth and the nasopharynx. There is tumor tissue extending into the nasal cavity from this side. This slide is one which cannot be made with the original EMI-Scan. It takes a total body scan to do this. The head was cut vertically, and we have a coronal section. As you can see the tumor invades the middle fossa. Here is the sphenoid sinus invaded from the left side whereas the right side is normal. The EMI-Scan should be very helpful in demonstrating these tumors that Doctor Alper has described. Thank you. DR ROBERT W. HOLLENHORsT. I, too, was intrigued by this very fine paper. We encounter one of these occasionally at the Mayo Clinic. My colleagues and I reported one case in the Archives of Ophthalmology in the November 1957 issue. The findings were very similar to those reported by Doctor Alper. Our patient was a 60-year-old nurse, admitted to the hospital complaining of failing vision of five weeks' duration. Four months prior to her admission she had noted a full headache and was diagnosed by a physician at home as having hyper-

Alper 80Ape tension. The headaches became progressively more severe; and, five weeks before admission, the pain which had been rather generalized then localized to the left infraorbital region. She developed diplopia and blurred vision in the left eye. The left eye swelled shut, and within 24 hours she was blind in this eye. During the next few days she lost all of her central vision as well as the temporal field in the opposite eye. The acuity was 3/200 in the right eye. At exploration we found a large cyst of the sphenoid sinus which was drained through the intracranial route, and then an opening was made through the sphenoid sinus into the pituitary fossa. She recovered almost all her vision in the re-

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maining eye although the one that originally went blind remained blind. I'd be curious to know whether Doctor Alper had come across cases prior to our 1957 report because we looked everywhere and couldn't find a similar report. Thank you. DR ALBERT D. RUEDEMANN. Mr President. I would -like to thank our new member for his first paper and ask two questions. The first one I would ask is why is it that we see so many mucoceles or pyoceles of the frontal sinus and so few mucoceles or pyoceles of the sphenoidal sinus? I am not quite sure by the author's statement whether we are talking about mucoceles or pyoceles because I think there might be an etiological difference between the two. I would ask him to differentiate these two terms. DR ALPER. Mr Chairman, I would like to thank all of my discussants, and especially Dr Harrington, for being so kind to initiate the discussion. I felt presumptuous in giving a paper at my first meeting. To have such a nice reception makes me feel that the effort was worth while. Dr Harrington, I think, in essence, answered Dr Ruedemann's question that perhaps we have been missing the diagnosis of sphenoid sinus mucoceles and that they are more common than we realize. Certainly, with the onset of "CAT fever," more of these are going to be found. Like Dr Kearns, we have not seen a mucocele since we have had computerized axial tomography. We have had one patient with a sphenoid sinus mucocele in the past six months on the Otolaryngologic Service, but the ear, nose and throat surgeons did not obtain a scan. They are not quite as enthused with this new modality as we are and have not fully utilized the CAT for diagnostic procedures. We have had examples of mucoceles in the frontal and ethmoid sinuses, but we have not as yet had a sphenoid sinus mucocele demonstrated on our CAT. Dr Hedges reports on the only other case in the literature (reported by Doyle and Simeon in the Archives of Neurology) of bilateral occlusion of the internal carotid artery demonstrated by arteriography. There are no other cases in the world literature that I have reviewed. Dr Hollenhorst's patient is the only one up until 1957 that had transcranial drainage without complication. Drs McFarland, Ommaya, and co-workers at NIH had an identical patient that was drained transcranially. They got into a lot of trouble with meningitis and it is for this reason that the transsphenoidal approach is recommended. The plea to

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keep the patients out of neurosurgical hands, unless the neurosurgeon is able to handle the transsphenoidal route, is important to avoid intracranial complications. In answer to Dr Ruedemann's other question, no one has really demonstrated why there are more of these mucoceles in the other paranasal sinuses and why they are so rare in the sphenoid sinus. In answer to Dr Ruedemann's question regarding terminology of "mucopyocele or pyomucocele"; when mucoceles become infected they become pyomucoceles or mucopyoceles, the terms are synonymous. However, they can cause symptoms even when they are mucoceles. The major symptom is that of headache. The headache is characterized, at least in all of our patients, and in Dr McFarland's patient who was reported in the Archives of Neurosurgery, as being most severe in the supine position and relieved in the erect position. I want to thank the other discussants again and the audience. Thank you very much.