VISUAL PROGNOSIS OF OPTIC NERVE SHEATH MENINGIOMAS PRODUCING SHUNT VESSELS ON THE OPTIC DISK: THE HOYT-SPENCER SYNDROME* BY Robert W. Hollenhorst, Jr., MD (BY INVITATION), Robert W. Hollenhorst, Sr., MD AND (BY INVITATION) Collin S. MacCarty, MD SHUNTING OF THE RETINAL VENOUS BLOOD INTO THE CHOROIDAL CIRCULATION MAY
indicate a meningioma of the optic nerve sheath. However, such shunts are most commonly due to occlusive retinal venous disease, glaucomatous optic atrophy, or one of the retinal proliferative vascular syndromes. Occasionally, they are of congenital origin. The quatrad of slowly progressive loss of vision, increasing pallor of the optic disk, opticociliary (retinochoroidal) shunt veins, and indentation of the posterior pole of the eye is virtually diagnostic of primary orbital meniIngioIna growiIng in a wrap-around fashion about the optic nerve. Although Salzmann' probably was the first to describe acquired shunt veins of the optic disk, he found them in a pathologic specimen and not oIn clinical examinatioin; and they may have been of congenital origin because there was an associated coloboma. Elschnig2 described a meniingioma involving the orbit which produced papilledema and a markedly exophthalmic eye. In the extirpated eve, he traced the shunt veins from the retina through the choroid and into the vortex veins but could not follow them further. In his papers,23 he described various forms of retinochoroidal venous and arterial communications. Recent interest in this subject stems from the stimulating papers of Frisen, Hoyt, and Tengroth4 and of Spencer.5 These authors postulated that most such patients initially have edema of the affected optic disk and that the outlook for preservation of vision is poor once the opticociliary veins have developed.
*Fromn the l)epartmient of Ophthalhnologv (Dr Holleinhorst, Jr. anid Dr Hollenihorst, Sr.) anid the D)epartment of Neuirologic Surgery (Dr NMacCartv), Mavo Clinic anid Mayo Found(lationi, Rochester, Minnesota.
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The nine patients whose case histories are presented had remarkably uniform historical and clinical courses. The first two patients had bilateral orbital tumors, and the other seven had unilateral tumors. REPORT OF CASES CASE 1
A 26-year-old man came to the Mayo Clinic oIn Feb. 4, 1974. His left eve had been blind since the age of 3 years. The blindness was ascribed to a blow oin the head. The right eye had beeni normal until it began to lose vision in August, 1973. Visual acuity was 20/30, 14/24 in the right eye. The left eye was without light perception. The visual field of the right eye was contracted (Fig. IA). There were large opticociliary shunt veins on both optic disks; in the right eye, some of these veins coursed through the upper temporal choroid. The right optic disk was pale grade 2 (on the basis of 1 to 4), and the left disk was pale grade 4 (Fig. 1B and C). Computerized tomogramns, optic canal and skull roentgeniogramns, and carotid anigiograms showed no abnormnalities. At operation on Feb. 14, 1974, a small
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(Case 1) A: Visual field of right eye has expanded postoperatively but is markedly contracted due to optic nerve atrophy. Left eve is blind. B: Two years after operation. Vision, right eye, further deteriorated. c: Two and a half years after operationi. Further deterioration of vision.
c
psammniomatous meninlgionsa was removed from its site just lateral to and beneath the right optic canal and extendinig into it. The right orbit was not unroofed nor was the the left orbit explored. Postoperative visual fields (Fig. 2A) of the right eve were improved. ExaminiatioIn in July, 1974 and July, 1975 showed nIo chainge. The exaiiinlationi in Junie, 1976 showed further loss of central visioIn and further (lepression of the visual field (Fig. 2B). OIn the basis of positive findilngs onl a caroti(l anigiogramn, a seconid operationi was donie oni Junie 8, 1976. After unroofiing the right orbit, an infiltratinig imeninlgiomua was founid envelopinig the optic nerve. Not all of the lesioin could be removed. Postoperative visual fields were uis-
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changed, but study done on Nov. 22, 1976, showed further deterioration (Fig. 2C). Further surgerv was considered injudlicious. Although the left orbit was not explored, the symmetry of the visible chaniges in the two eves seemed to be compatible with bilateral orbital meninlgiomnas. CASE 2
An 18-year-old woman was seen on Jan. 16, 1974, stating that visioIn in her right eve had been poor since the age of 6 years and poor in her left eve since April, 1973. The right eve had progressively lost vision and becamiie totally blind when she was 16 years old. Bilateral angiogramns in July, 1973 showed no abnormalities. There was no history of papilledema. Both optic disks were pale: grade 4 of the right anid grade 2 of the left. There were two opticociliary shunt veins on the left optic disk, one at the 5:00 o'clock and one at the 8:00 o'clock positioIn, but noine on the right optic disk. The right eve was blind anid was exotropic 10 degrees; the left eye had vision of 20/70, 14/21. Computerized tomogramis, skill and optic canal roentgeinograms, anlgiogrami-s, and pneumioenicephalogramiis all gave normal results. Visual field examinatioil showed a blindl right eye and an arcuate scotoina with reduced cenitral visioIn in the left eve (Fig. 3). There was no measurable exophthalmnos. Craniotomvy on Jan. 21, 1974, revealed a ring meningiom-a of psammllnomuatous type enlcasinig the right optic nerve in the dorsal aspect of the optic cainal andl a similar one around the left optic nerve in the optic canal. These tumors were removed, but no improvement in the vision ensued postoperatively. No followtip was possible. CASE 3
A 41-year-old womain was seen at the MIayo Clinic in February, 1958 because of blurred vision in the right eye since October, 1957. In December, 1957, anl ophthalmnologist noted edema of the right optic nerve and treatedl her with nicotiinic acid and later with prednisolonie. However, visuial acuity continlued to worsen. Examiinationi showed 4 diopters of papilledema of the right optic dlisk, without hemorrhage, and a normnal left optic disk. Visual acuity was 20/80 in the right eye, improvable to 20/25 with a +1.00 lens, and 20/20, 14/21 in the left eye. The visual field of the right eye was mildly contracted for small targets and the blind spot was enlarged; the field of the left eye was normnal (Fig. 4A). Roentgeniogramiis of the skull, pneumoeincephalogramns, and ventriculogramns gave negative results. An orbital tumor was suspected, but exploration was not advised. One mointh later, the acuity of the right eye had decreased to 20/200, 14/56 and improved to 20/30, 14/21 with a +2.00 lens, indicative of increasiing inldenitation of the posterior pole of the right eye. The papilleclemia was 5 diopters. Exophthalmomiieter readinigs were 18 mnim on the right and 17 min left. The visual field showed only an enlarged blind spot. Orbitonometry inidicatedl increase(l resistance in the right orbit, suggestive of tumor.
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FIGURE 3
(Case 2) Blind right eye. Arcuate field defects, left eye.
In November, 1958, the field of the right eye was more contracted (Fig 4B), and the right disk was still elevated 5 diopters (Fig. 5A). When she returned in April, 1959, the right eye was totally blind and the papilledema measured 4 diopters. There was moderate pallor of the disk and still only 1 mm of proptosis. The opticociliary shunt veins were first visible, dimly seen through the papilledema, in 1966 (Fig. SB). At her last examination in 1972, the right eye was exophthalmic (3 mm), blind, and exotropic (10 degrees). The papilledema measured 11/2 diopters, with numnerous venous shunts on the disk. In 1974, a letter indicated that no change had taken place.
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(Case 3) A: Contraction of field and enlarged blind spot, right eye. Normal left. contraction of field, right eye.
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CASE 4
This patient was 53 years old in March, 1973 when she was first seen at the Mayo Clinic. She had noted a gradual painless decrease in vision of the left eye since December, 1971. She had received oral steroids since August, 1972, without effect on vision.
FIGURE 5
(Case 3)
Right eye with 5 diopters of papilledema. November, 1958. B: Right eye with 4 diopters of papilledema and with visible opticociliary shunt veins, 1966. A:
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(Case 4) X Normal right eye. Greatly contracted field, left eye, March, 1973. B: Pronounced further loss of vision 4 months after operation, June, 1973.
The acuity was 20/14, 14/21 in the right eye and 20/30, 14/21 in the left eye. External examiniationi showed no abnormalities other than an exophthalmomneter reading of 14 mm on the right and 17 mm on the left. There was an afferent defect in the reactions of the left pupil. The fundus of the right eye was normal, but the left disk was edematous (4 diopters). The field of the left eye was generally depressed and that of the right eye was normal (Fig. 6A). Roentgenogramus of the head, orbital tomograins, angiograins, and orbital venograms all gave normal results. Transfrointal exploration showed evidence of high orbital pressure with a thinned orbital roof andl lateral wall. After the orbit was unroofed, a meniingiotheliomatous meninlgiomia was removed from the optic nerve sheath where it extended from behind the globe to the ligamenit of Ziiun. The tumor arose from the attachment of the dura to the clinoid process and from the inferior aspect of the optic canal. Some visioIn was lost durinig the operation. Further visioIn was lost (Fig. 6B) in the left eye during the ensuing 4 months. The left disk was edlematous and was elevated 2'/2 diopters. There was no exophthalmos. In November, 1973, visual acuity was 20/60, the visual field had diminished to 4 degrees, the optic dlisk was pale grade 3 with mild edema, and there was 2 mnm of exophthalmos. The back of the globe was inldente(l about 6 diopters. In December, 1974, acuity of the left eye was 20/100, the disk was pale grade 4, the visual field was reduced to 1 degree, and the papilledema measured 1'/2 diopters. Opticociliary shunts were observed for the first time.
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At the last examination in March, 1976, the left eye had light perception only and the right eye remained normal. No further surgery was advised. CASE
5
A 61-year-old woman was seen at the Mayo Clinic on Aug. 24, 1965, after pallor of the optic disk and a deficit in visioIn of the right eye were discovered. She stated that she had not noted the loss of vision until it was poinited out to her. The vision of the right eye was reduced to finger countinig. The left eve had 20/20, 14/14 visioIn. The right optic disk was pale grade 2; it had ragged marginis and was slightly edematous. The retinal veins were darkenied, ancd there were opticociliarv shunt veins at the 4:00 and the 7:00 o'clock imarginis of the disk (Fig. 7A). There was no proptosis; tensions and movemnents were normal. The visual field of the right eye was depressed and contracted (Fig. 7B). Roentgenograms of the skull showed no abnormality. The patient refused other tests but returned for an examinationi of her eyes in January, 1966, July, 1966, anid July, 1967. At each visit, visioIn of the right eve was worse; and at the last visit, the eye was blind. Roentgenogramns of the skull in July, 1967 showed an osteoma on the upper aspect of the right anterior clinoid process, probably the site of origin of a meninigiomia. Although she refused surgerv, she returned on numilerous occasionis. A computerized tomogram in September, 1975 showed enlargemnenit of the optic nerve (Fig. 8) Other than the development of extreme pallor of the right optic disk, there
has been nio other maniifestationi of continiued growth of the tumior; the opticociliarv shunt veins remainied unchanged, and no proptosis was ineasuredl at any timne. CASE 6
A 47-year-old womilanl was seeni at the Mayo Clinic in Jtuly, 1975 for inivestigationi of chronic fatigue and depressioni. The visioIn of the right eve had begun to deteriorate 13 years previously and within 4 years was blind. At that time, extensive tests showed no abnormiiality and the optic atrophy was thought to be due to drusen. The examiniationi showed a blind right eye and a normnal left eve. The right optic disk was pale grade 4, anid there were opticociliary shunt veinis oni the disk; and the posterior pole of the globe was inidenited about 3 diopters (Fig. 9). Ther-e was 11/2 mm of exophthalmos of the right eye, mild lateral deviationi of the eve, and grade 2 paresis of the medial rectus imuscle. The visual field of the left eve was normial. FIGURE 7 (opposite) (Case 5) A: Right disk with pallor grade 2, slight edemna anid shunits at the 4:00 anid 7:00 o'clock positionis. Large commlluniicating choroidal vein at the 7:00 o'clock but not at the 4:00 positioni. B: Contracted field, right eve. Normal left. August, 1965.
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FIGUeRE 8
(Case 5) Computerized tomogram showing enlarged right optic nerve, September, 1975.
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FIGURE 9
(Case 6) Pallor grade 4 of right optic disk and shunt veins at the 5:00 and 8:00 o'clock positions.
The patient refused further examination. However, there seemed to be no doubt that this was a meningioma of the optic nerve sheath. CASE 7
A 49-year-old woman was first examined at the Mayo Clinic on Nov. 15, 1976. She had gradually lost the vision of the right eye, beginning in 1966, and it had been blind since 1971. In 1968, the right optic disk was swollen. After extensive tests, including brain scans and angiograms, all of which were negative, she consulted several clinics. The loss of vision was thought to be due to drusen of the optic disk. Exophthalmos of the right eye was first seen in January, 1976. A computerized scan at that time was interpreted as showing hypertrophy of the muscle cone, enlargement of the optic nerve, but no evidence of tumor. This same scan was later reviewed and interpreted as showing proptosis with a thickened right optic nerve near the orbital apex, consistent with meningioma. Examination showed a totally blind right eye and a normal left eye. There was 3 mm of exophthalmos of the right eye and grade 4 pallor of the optic disk, with evidence of previous edema and with opticociliary venous shunts (Fig. 10) at the 6:00 and 8:00 o'clock positions. Exploration was not advised unless the exophthalmos progressed.
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FIGURE 10
(Case 7) Pallor grade 4 of right optic disk, with shunt veini at the 6:00 and 8:00 o'clock positions.
C(ASE 8
A 47-year-old man was examined at the Mayo Clinic on June 8, 1976. The visionl of his right eye began to fail in 1962, and the eye became blind within 3 vears. Extensive investigation at that time failed to reveal a cause. Details of that examinatioin were not available except that in 1962 he had 20/30 visioIn anld papilledema in the right eye, 20/20 vision and a normal left eye, and by 1971, there was no light perception in the right eye. The examination showed a blind right eye with 2 mm of exophthalmos, inild limitation of movement in all directions, and no orbital resistance to retropulsion. There was grade 3 to 4 pallor of the optic disk, with evidences of previous papilledema and prominent opticociliary shunt veins on the optic disk (Fig. 11). Computerized tomography showed enlargement of the optic nerve compatible with a meningioma of the optic nerve sheath or an optic nerve glioma (Fig. 12). Surgery was not advised unless the exophthalmos increased significanitly. The left eve remained normal throughout. CASE 9
A 40-year-old woman was not seen at our clinic, but data were supplied bi a clinic in another state. The patient first sought help in February, 1972 and colmplailled that she had blurred visioIn in the right eye for 9 moniths. The acuity was 20/30 in the right eye and 20/20 in the left eye. The right optic disk was mildly edemna-
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FIGURE 11
(Case 8) Pallor grade 3 to 4 of right optic disk. Shunts at the 3:00, 7:00, and 11:00 o'clock positioins, with huge choroidal communications.
tous, and there were three opticociliary shunt veins on the disk (Fig. 13A). Visual field examination of the right eye showed a dense inferior altitudinal defect and genieralized constriction of the field (Fig. 13B). The examination of the left eye gave norm-al results. Results of tomograms of the optic foramina and roentgenograms of the skull were normnal; the right optic canal and orbit were slightly smncaller than the left. By March, 1972, the acuity of the right eye had decreased to 20/60, and the visual field was worse. Carotid arteriograms and a pneumoencephalogram revealed no abnormalities. Repeated examinations failed to uncover the cause of the condition, and the visioIn remained fairly stable until June, 1973, when a rapid diminution to 20/400 occurred in the right eye. The disk had turned pale, and only a minute residual field of visioIn remlainled in the eye. By Septeinber, 1974, when she returned because of increasinigly severe headaches for 1 month, the right eye had only light perception; and papilledema was observed in the left eye. A radioactive scan and a pneumoencephalogram showed a imass in the anterior midlinie frontal region. Craniotomy proved that this was a psammnomnatous meningioma attached to the crista galli. It was not conttinuous with the imeninlgioma that surrounided the optic nerve. Postoperatively, light perceptioni was present in the right eye; blut a year later, the eve was enitirely blind.
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FIGURE 12
(Case 8) Computerized tomogram showing enlargment of right optic nerve. SUMMARY OF DATA
Of the nine patients, two were men and seven were women. One man and one woman had bilateral meningiomas. Six patients had the right eye affected, one had the left eye, and two had both eyes affected. The ages at onset of the visual deficit among the patients with unilateral disease were 33, 34, 39, 39, 40, 51, and 61 years and among those with bilateral disease, 3 and 6 years. The man who had both orbits involved was said to have gone blind in the left eye at the age of 3 years and his right eye began to fail at the age of 25 years; the woman with bilateral involvement lost vision in her right eye when she was 6 years old and vision of her left eye was first affected at the age of 17 years. Progressive loss of vision to absence of light perception showed a remarkably consistent course, as it occurred in 2, 2 to 3, 3, 3, 3, 4, and 5 years in the seven patients with unilateral defects. The time periods in the patients with bilateral defects were not certain because one of the patients was thought to have lost vision in his left eye as a result of a blow on the head when he was 3 years old, and he became blind in the right eye in 3 years; the other patient lost vision in her right eye during a 10-year period, and no follow-up data on her left eye were available.
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VO.S.:20/20
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B FIGURE 13
(Case 9) A: Right optic disk with edema and three opticociliary shunt veins. B: Pronounced contracted visual field with arcuate defects, right eye. Left eye is normal.
Hollenhorst et al Prior or concurrent papilledema was documented in the affected eye in six of the nine patients and was questionable in another patient. Papilledema was absent in the two patients with bilateral disease. Proptosis was documented in five patients, being 1, 1½, 2, 3, and 3 mm and always straightforward. Posterior indentation of the globe was noted in five patients, being as much as 6 diopters in one. Only three patients had defects in motility; in all, it was mild. All of the patients had roentgenograms of the skull, and generally, the results were negative. Eight had roentgenograms of the optic canals, and results were negative in all. Seven had cerebral angiograms, and all had normal results. Three had negative pneumoencephalograms; one had a negative ventriculogram; and one had a negative venogram. Skull roentgenograms taken later in case 5 showed an osteoma that was not seen 2 years previously, and in case 9, a frontal lobe tumor developed and was visualized on a pneumoencephalogram. Five patients had computerized tomograms; three tomograms showed the orbital tumors and two failed to do so. Four patients (cases 1, 2, 4, and 9) underwent operation, with removal of all resectable tumor. Although none of the four lost further vision during the surgery, three continued to lose vision during the ensuing years and the fourth was lost to follow-up. Pathologic diagnosis was psammomatous meningioma in three patients and meningiotheliomatous meningioma in the other. The assumption of similar tumors being present in the five orbits that were not explored is open to question, although we have little doubt that they also were meningiomas because findings were so similar. Also, among the five cases of unverified disease, three had positive findings by computerized tomography. The opticociliary shunt veins noted on the optic disks were present in 10 of the 11 eyes involved by these tumors. In one patient (case 2), shunts were observed in the eye with more recent loss of vision but none in the blind eye. There were from one to three shunts, and these could be seen to communicate with large choroidal veins in four patients whose choroidal vessels were visible. All except two patients (cases 3 and 4) had shunts at the first examination, even though the onset of visual symptoms in at least three others (cases 1, 2, and 9) had occurred only within the previous 6 to 9 months. In the other patients, the visual loss had begun between 3 and 14 years previously. 156
DISCUSSION
Opticociliary shunt veins are fairly common in eyes that have suffered from a prior occlusion of the central retinal vein, or a branch of it, as well
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as in eyes with glaucomatous excavation. Also, over the years, there have been many descriptions of various anomalies of the circulation, including opticociliary veins of physiologic type.2,36-10 Venous shunts that develop because of progressive interference with the venous outflow through the central retinal vein in the optic nerve just behind the globe have a different appearance, as they are convoluted and dilated channels that develop from preexisting capillary communications between the retina and the choroid. These occur with optic nerve gliomas, i"' chronic atrophic papilledema, 12 and orbital cysts, 13 as well as with orbital meningiomas. Although the association of acquired opticociliary shunt veins with orbital meningiomas has been known at least since 1893, the recent publications of Frisen, Hoyt, and Tengroth,4 and Spencer5 have revived this knowledge. Meningiomas that arise primarily from the meningeal coverings of the optic nerve within the orbit are relatively rare. Newell and Beaman'4 found only two of 143 patients with meningioma; one patient had 19 mm of proptosis caused by a malignant meningioma, but neither of the two patients had shunt veins. None of the 106 patients with sphenoid ridge meningiomas described by Kearns and Wagener'5 had shunt veins, even those with orbital invasion. Karp and coauthors16 described 25 patients with primary intraorbital meningiomas; there were 21 women and four men with an average age of 31.7 years and a median age of 38 years. Ten patients were less than 20 years of age, and six were less than 10 years of age. Fifteen patients had the right orbit involved, and eight had the left; in two, the affected side was unknown. Ten had papilledema of the affected eye, six had lid edema, and four had limited ocular movement. Only one ofthe ten patients less than 20 years old is alive without recurrent tumor, and five of the ten had to undergo reoperation. Of the 13 patients more than 20 years old, 10 were alive and well 3 to 24 years later. We found no evidence of invasion of the globe in any of our patients, but Coston17 described a patient in whom the meningioma invaded the choroid and retina, and he showed a photograph of a fundus with a typical opticociliary shunt vein. Martin and Schofield's'8 patient was a 3-year-old child with invasion but no shunt veins. Rodrigues and coauthors'9 reported on a case similar to that of Coston's. Walsh20 emphasized the preponderant involvement in females and the association with neurofibromatosis. Moore's2' patient was similar to one of our patients (case 9) in that neither had continuity between the meningioma of the sphenoid ridge and the one involving the optic nerve. He postulated that this may have
Hollenhorst et al been metastasis. We considered that our patient (case 9) had two separately developing meningiomas. In the series of Frisen and coauthors4 the four patients with the triad ofopticociliary veins, disk pallor, and visual loss included two with bilateral defects. Although the report stated that the four were "middle-aged females," 45, 49, 40, and 55 years old, the onset was at age 32 years in the 45-year-old, 40 years in the 49-year-old, 19 years in the 40-year-old, and "blind for years" in the 55-year-old. In these respects, they are similar to our series because seven of our nine patients were female and most were in their 30's or were younger at onset. Three of their patients had mild exophthalmos, as did ours. Frisen and coauthors4 and others5'22 postulated that nearly all patients with meningiomas of the optic nerve sheath initially had edema of the optic disk owing to passive congestion caused by compression of the retrobulbar portion of the central retinal vein and that bypass channels develop within the eye by the dilatation of preexisting capillaries that connect the central retinal vein with peripapillary choroidal veins. As the tumor gradually destroys the optic nerve, the vision is lost and pallor of the nerve head develops, while the shunt veins bypass the central 158
vein.
While this sequence seems to be followed in general, our patients 1, 2, and 9 seem to have developed shunts without edema of the optic disks; and these shunts may have developed before the onset of any symptoms or signs of loss of vision. Of the authors who have written on these tumors, so far as we can determine, only Spencer5 mentioned the indentation or flattening of the globe and the development of hypermetropia in consequence. However, this was observed in five of our patients and probably was overlooked in others of the series. The prognosis for vision was invariably grim for all nine of our patients and seemed to be similarly poor for those reported in the literature to date, whether with or without surgical therapy. The poor outlook for vision probably results from the characteristic growth of the tumor along the meninges, enwrapping the optic nerve and destroying the pial blood supply to the nerves. Surgical removal of the tumor often causes further destruction of the blood vessels and subsequent deterioration of vision. SUMMARY
Nine patiei)ts, including seven women and two men, had meningiomas of the optic nerve sheath. The defect was bilateral in two, in the right
Nerve Sheath Meningiomas
159 eye in six, and in the left eye in one. Most had edema of the disk, and all had progressive loss of vision to blindness in the affected eye owing to optic nerve atrophy. In 10 of the 11 affected eyes, opticociliary shunt veins developed on the optic disk. Exophthalmos was mild and not more than 3 mm in any patient. Ocular movement was mildly impaired in three patients. Indentation and flattening of the posterior pole of the eye was documented in five eyes. Nine of the eleven eyes went on to blindness; one was worse after operation, and the eleventh was lost to follow-up. Surgical treatment has not been effective in these cases or in those reported in the literature. ADDENDUM
Since this paper was prepared, three additional patients with optic atrophy and associated opticociliary shunt veins have been observed: two had recurrent sphenoid ridge meningiomas with orbital extension, and the third had a blind left eye probably due to huge drusen within the optic disk. REFERENCES 1. Salzmann M: Zur Anatomie der angeborenen Sichel nach innen-unten. Albrecht von Graefes Arch Ophthalmol 39 Part 4:131, 1893. 2. Elschnig A: Ueber opticociliare Gefisse. Klin Monatsbl Augenheulkd 36:93, 1898. 3. Elschnig A: Cilioretinale Gefiisse. Albrecht von Graefes Arch Ophthalmol 44:144, 1897. 4. Frisen L, Hoyt WF, Tengroth BM: Optociliary veins, disc pallor and visual loss: a triad of signs indicating spheno-orbital meningioma. Acta Ophthalmol (Kbh) 51:241, 1973. 5. Spencer WH: Primary neoplasms of the optic nerve and its sheaths: clinical features and current concepts of pathogenetic mechanisms. Trans Am Ophthalmol Soc 70:490, 1972. 6. Hoeg N: Ueber optico-ciliare Vener. Abrecht von Graefes Arch Ophthalmol 55:256, 1903. 7. Duke-Elder S: System of Ophthalmology. Vol 3, Part 2. St. Louis, C. V. Mosby Company, 1963, pp 792-793. 8. Winther E: Abnormal course of retinal blood-vessels of the same type found in a father and his son. Acta Ophthalmol (Kbh) 17:236, 1939. 9. Braune: Ein Beitrag zur Kenntnis optikociliarer Gefisse. Klin Monatsbl Augenheilkd 43:579, 1905. 10. Kraupa E: Beitrage zur Morphologie des Augenhintergrundes. IV. Optikoziliare Arterien, Optikusrandvenen und optikochorioideale Venen. Klin Monatsble Augenheilkd 72:724, 1924. 11. Hoyt WF, Beeston D: The Ocular Fundus in Neurologic Disease: A Diagnostic Manual and Stereo Atlas, St. Louis, C. V. Mosby Company, 1966, p 42. 12. Hedges TR: Papilledema: its recognition and relation to increased intracranial pressure. Surv Ophthalmol 19:201, 1975 13. Miller NR, Green WR: Arachnoid cysts involving a portion of the intraorbital optic nerve. Arch Ophthalmol 93:1117, 1975. 14. Newell FW, Beaman TC: Ocular signs of meningioma. Am J Ophthalmol 45:30, 1958.
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15. Kearns TP, Wagener HP: Ophthalmologic diagnosis of meningiomas of the sphenoidal ridge. Am J Med Sci 226:221, 1953. 16. Karp LA, Zimmerman LE, Borit A, Spencer WH: Primary intraorbital meningiomas. Arch Ophthalmol 91:24, 1974. 17. Costoni TO: Primary tumor of the optic nerve: with report of a case. Arch Ophthalmol 15:696, 1936. 18. Martin VAF, Schofield PB: Meningioma invading the optic nerve. Br J Ophthalnol 41:161, 1957. 19. Rodrigues MM, Savino PJ, Schatz NJ: Spheno-orbital meningioma with optociliary veins. Am J Ophthalnol 81:666, 1976. 20. Walsh FB: Meningiomas, primary within the orbit and optic canal. In Fifth Miami Neuro-ophthalmological Symposium. Vol 5. Hollendale, Florida, Hollendale Press, 1971, pp 240-266. 21. Moore CE: Sphenoidal ridge meningioma with optic nerve metastasis. BrJ Ophthalmol 52:636, 1968. 22. Walsh FB, Hoyt WF: Clinical Neuro-ophthalmology. Vol 3, Third edition. Baltimore, Williams & Wilkins Company, 1969, pp 2080-2083.
DISCUSSION
DR ALAN M. LATIES. Drs Hollenhorst, Hollenhorst and MacCarty are to be congratulated on a careful clinical study of optic nerve sheath meningioma. Although they describe each case in considerable detail, they focus their presentation largely on two questions: the relationship of opticociliary veins to prior edema ofthe optic nerve head and the meaning of the appearance ofan opticociliary vein to vision. Attention is paid to disc edema to test what mnight be called the congestive hypothesis by Frisen, Hoyt and Tengroth. That is, that an opticociliary vein develops when the venous drainage from the nerve head is impeded, such impedence first causing edema. With minor exceptions the authors confirm a congestive hypothesis: specifically, there is clear evidence of disc edema in six of nine patients, partial but suggestive evidence in one of nine and in the other two the history is so long and the eye examination occurred at such a late date that there is a chance that unobserved disc edema might well have been present for a period of time. So far as visual prognosis is concerned, a single word sums it up: dismal. In most reported series and in the present report, an optic nerve meninigioma severe enough to cause disc edema and visible opticociliary shunts, leads to irreversible loss of vision. Interestinigly, the merits of doing a careful clinical review are once again illustrated through the finding of acquired hypermetropia in five patients. Although acquired hypermetropia due to posterior flatteninlg of the globe had beeni previously pointed out by Spencer, in many other instanices it apparently has been overlooked. Lastly, there is a questioni about the precise nature of anl opticociliarv vessel. Under the heading of congeniital abnormnalities, Walsh and Hoyt speak of abnormnal communiicationis between the retinial anid ciliarv systems to include an opticociliarv vein. Similarly, Henkinid and Benjamnini in a recent review of vascular anomialies
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and neoplasms of the optic nerve head (Trans Ophthalmtiol Soc UK 96:418-423, 1976) speak of them in two senses. First, as a congenital anomaly. Second, "the vast majority are developmental resulting from a partial block of the central retinal vein with secondary enlargement of the preexisting capillary network of the optic nierve head. This capillary bed, derived from the posterior ciliary circulationi, would normally drain from the central vein." Somewhat further along, Drs Henkinid and Benjamnini make the point that "opticociliary veins are found mnost frequently after a central retinal vein occlusion and may be the only obvious se(luelae of such an occlusion." In stating that opticociliary veins derive from enilargemenit of a preexisting capillary network, Drs Henkind and Benjamini in fact reiterate what apparently is a consensus concerninig their derivation. However, there is cause to question this consensus; cause instead of wonder whether there mnight not exist in most normal people true venous channels at the optic nerve head draining to the choroid, channlels that under stress can dilate. Certainlv such should be suspected both from clinical and from experimental grounds. A detailed review by Hayreh (BrJ Ophthalmizol 49:626-645, 1965) of many aspects of this matter is available. Equally importanit, Fujino, Curtin and Norton (Arch Ophthal7alol 81:395-406, 1969) showed in the owl monkey that the difference between occlusioin of the central retinal vein at the surface of the optic disc versus its closure as it emerged from the optic nerve posterior to the globe were entirely differenit in consequenice, the former causing a destructive hemorrhagic retinopathy while the latter, although it temporarily impedes venous outflow, vields a far less dIramnatic clinical picture and thus must be moderated by available alterniate routes of drainiage of somewhat greater capacity thani would be afforded by a capillary nietwork. Further evidence alonig this line is available from inijection studies. For inistanice, Aniderson (AmiiJ Ophthalmtiol 20:341-351, 1970) has writtell, "Not all the vessels that extend radially about the optic nerve in the choroid are arteries. Somne of these simall vessels could be traced back as tributaries of a vortex vein. Thus the capillary network of the optic nerve head has both arterial and venious conniiections with the choroidal circulation." Similar observations have been made by WVybar (Amii J Ophthalinol 38:513-518, 1954) and others. In closing, I wanit to thanik Drs. Hollenhorst, Hollenhorst and MacCarty for suppl,ying the paper- to me in plenity of time anid onice agaill to congratulate them for the high quality of their clinical review.
Dmi Fm\xK B. WVALSmm. I congratulate the essayist who bears his father's nlame. I amii (qtuite ssure that his father will remember this mnornlilng as a proud one. The paper was valuable. My experienice with optic nierve sheath meninlgiomiias has been that visual acuity has been lost invariablv. This might occur if the meninlgiomiia was founid to be ectopic anid outside the optic nierve sheath but I do niot have experienice in such a catse. Not related to what l)r Holleinhorst has described we recently have observed a young Imlanl in whomn our nieuroradiologist suggested that pnieumnosinius dilitans well mlight explaini bilateral loss of visioIn.
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An 18-year-old boy was shown to have a tremendous enlargement of the sphenoid sinus with a portion of its protrusion extending superiorly almost to the level of the anterior portion of the sella turcica. Loss of vision was gradual in both eyes of this patient and the X-ray picture I do not have this morning. The protruding sinus was considered for a time as a possible explanation for the progressive bilateral loss of vision. Our experience with pneumosinus dilitans as regards symptomatology was nil. The patient and his parents refused transcranial operation and the boy was returned to the hospital weeks later with the vision reduced to light perception in both eyes. There was pronounced pallor of both discs. On this admission a transcranial operation revealed a meningioma surrounding each optic nerve as it approached the optic canal. These tumors were very small. Tomograms and an EMI-Scan had been described as negative. After operation the patient retained light perception only in each eye. Certainly pneumosinus dilitans was not the proper diagnosis. DR WILLIAM RICHARD GREEN. I would like to raise one point for consideration. Arachnoidal or dural cysts of the optic nerve can simulate the picture of intradural meningiomas within the orbit and should be considered in the differential diagnosis. The presence of an optociliary shunt may be a clue to the presence of such a cyst. When orbital exploration is performed, palpation of the nerve may help to differentiate a dural or arachnoid cyst from a meningioma. Recognition that the lesion is a cyst saves the eye and excision of a portion of the dura in the area of a cyst may result in improvement of vision. DR DAVID COGAN. I realize that the Hoyt-Spencer thesis postulates an obstruction of the retinal vein and collateral drainage by the choroid. Yet these cilioretinal vessels seem to me to differ from the rete mirabile which one sees with central retinal vein obstruction. I wonder, therefore, if they may not represent, in some cases at least, drainage from the tumor itself. I have one pathologic specimen, for instance, where the meningioma had extended into the choroid and might well have utilized such drainage. It would be interesting to know, therefore, whether fluoroangiography showed an early fluorescence of these vessels as would be expected in tumor drainage, or a delayed fluorescence as would be expected with a relative obstruction. DR LAWTON S\trri. This is a very important paper. There is a definite tendency for optic nerve sheath meningiomas to be bilateral. We have had two cases of bilateral optic nerve sheath meningiomas and Dr Glaser has kindly given me notes on a third bilateral case. Interestingly enough, the field defect started temporally in one eye- this then spread until the eye went blind. It then started in the temporal field of the other eye and the last thing left was a nasal- field in the seconid eye. This would immediately make one suspect chiasmal compression. However, arteriograms and air studies were negative in all of these cases for years. The lesions were found by CT scan in only three of the five bilateral cases. Dr Glaser's patient was a 38-year-old woman whose left eye went totally blind at
163 Nerve Sheath Meningiomas age 5 years. At surgery recently when the right eye was involved she was found to have bilateral optic nerve sheath meningiomas. I would not have suspected that one could have an optic nerve sheath meningioma for 33 years with negative contrast studies but that was the report in his case. There have been some reports of efficacy of irradiation therapy on meningiomas. I have treated one patient with a clinical diagnosis of optic nerve sheath meningioma with radiotherapy with improvement from hand movements to 20/70 in the involved eye and she has held this for a year and a half. I believe we will sooIn find that irradiation therapy is the treatment of choice for optic nerve sheath meningiomas, when the diagnosis has been carefully established. I should like to congratulate Dr Hollenhorst and associates on this excellent and important paper. DR ROBERT HOLLENHORST. I wish to thank all the discussors. Doctor Laties, your point about the possible alternative origin of these vessels from other sources than those we have postulated may certainly well be true. I just cannot answer the question. Thank you, Doctor Walsh, for your kind remarks and for your presentation of a very interesting case. Doctor Green's and Doctor Smith's points are very well taken. If the patient has some vision, we do explore the orbit in the hope of restoring some vision. Two of these patients had a blind eye and refusea surgery. If some vision is present, I think one must consider other possible surgically treatable lesions such as an orbital cyst. Doctor Cogan, we have not obtained any ocular specimens; I cannot be certain that some of these cases may not have had invasion of the posterior aspect of the globe. Our fluorescein studies were quite inconclusive although we did not use this method in all cases. I now show four other cases we discovered since the paper was written. This is a patient who had a sphenoid ridge meniingioma. As you can see, there are some small shunt vessels on this disc as well as some residual papilledema and edema residues extending from the disc. The next patient has shunt vessels on the disc; he had a recurrent anterior clinoid meningioma. This next patient had hyaline masses in the disc and a small amount of vision in the eye. Over the course of eight years she developed 3 mm of proptosis, and some small shunt vessels in among the hyaline masses in the optic disc. This last case is a patient who had an optic nerve glioma extending from the back of the globe to the optic chiasm. Shunt vessels were noted on the initial visit along with some edema of the retina and extending to the macula. The next slide shows the same eye following extirpation of the optic nerve glioma. The optic nerve was severed just behind the globe. The shunt vessels have all disappeared. Thank you very much.
indicate a meningioma of the optic nerve sheath. However, such shunts are most commonly due to occlusive retinal venous disease, glaucomatous optic atrophy, or one of the retinal proliferative vascular syndromes. Occasionally, they are of congenital origin. The quatrad of slowly progressive loss of vision, increasing pallor of the optic disk, opticociliary (retinochoroidal) shunt veins, and indentation of the posterior pole of the eye is virtually diagnostic of primary orbital meniIngioIna growiIng in a wrap-around fashion about the optic nerve. Although Salzmann' probably was the first to describe acquired shunt veins of the optic disk, he found them in a pathologic specimen and not oIn clinical examinatioin; and they may have been of congenital origin because there was an associated coloboma. Elschnig2 described a meniingioma involving the orbit which produced papilledema and a markedly exophthalmic eye. In the extirpated eve, he traced the shunt veins from the retina through the choroid and into the vortex veins but could not follow them further. In his papers,23 he described various forms of retinochoroidal venous and arterial communications. Recent interest in this subject stems from the stimulating papers of Frisen, Hoyt, and Tengroth4 and of Spencer.5 These authors postulated that most such patients initially have edema of the affected optic disk and that the outlook for preservation of vision is poor once the opticociliary veins have developed.
*Fromn the l)epartmient of Ophthalhnologv (Dr Holleinhorst, Jr. anid Dr Hollenihorst, Sr.) anid the D)epartment of Neuirologic Surgery (Dr NMacCartv), Mavo Clinic anid Mayo Found(lationi, Rochester, Minnesota.
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The nine patients whose case histories are presented had remarkably uniform historical and clinical courses. The first two patients had bilateral orbital tumors, and the other seven had unilateral tumors. REPORT OF CASES CASE 1
A 26-year-old man came to the Mayo Clinic oIn Feb. 4, 1974. His left eve had been blind since the age of 3 years. The blindness was ascribed to a blow oin the head. The right eye had beeni normal until it began to lose vision in August, 1973. Visual acuity was 20/30, 14/24 in the right eye. The left eye was without light perception. The visual field of the right eye was contracted (Fig. IA). There were large opticociliary shunt veins on both optic disks; in the right eye, some of these veins coursed through the upper temporal choroid. The right optic disk was pale grade 2 (on the basis of 1 to 4), and the left disk was pale grade 4 (Fig. 1B and C). Computerized tomogramns, optic canal and skull roentgeniogramns, and carotid anigiograms showed no abnormnalities. At operation on Feb. 14, 1974, a small
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c
psammniomatous meninlgionsa was removed from its site just lateral to and beneath the right optic canal and extendinig into it. The right orbit was not unroofed nor was the the left orbit explored. Postoperative visual fields (Fig. 2A) of the right eve were improved. ExaminiatioIn in July, 1974 and July, 1975 showed nIo chainge. The exaiiinlationi in Junie, 1976 showed further loss of central visioIn and further (lepression of the visual field (Fig. 2B). OIn the basis of positive findilngs onl a caroti(l anigiogramn, a seconid operationi was donie oni Junie 8, 1976. After unroofiing the right orbit, an infiltratinig imeninlgiomua was founid envelopinig the optic nerve. Not all of the lesioin could be removed. Postoperative visual fields were uis-
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changed, but study done on Nov. 22, 1976, showed further deterioration (Fig. 2C). Further surgerv was considered injudlicious. Although the left orbit was not explored, the symmetry of the visible chaniges in the two eves seemed to be compatible with bilateral orbital meninlgiomnas. CASE 2
An 18-year-old woman was seen on Jan. 16, 1974, stating that visioIn in her right eve had been poor since the age of 6 years and poor in her left eve since April, 1973. The right eve had progressively lost vision and becamiie totally blind when she was 16 years old. Bilateral angiogramns in July, 1973 showed no abnormalities. There was no history of papilledema. Both optic disks were pale: grade 4 of the right anid grade 2 of the left. There were two opticociliary shunt veins on the left optic disk, one at the 5:00 o'clock and one at the 8:00 o'clock positioIn, but noine on the right optic disk. The right eve was blind anid was exotropic 10 degrees; the left eye had vision of 20/70, 14/21. Computerized tomogramis, skill and optic canal roentgeinograms, anlgiogrami-s, and pneumioenicephalogramiis all gave normal results. Visual field examinatioil showed a blindl right eye and an arcuate scotoina with reduced cenitral visioIn in the left eve (Fig. 3). There was no measurable exophthalmnos. Craniotomvy on Jan. 21, 1974, revealed a ring meningiom-a of psammllnomuatous type enlcasinig the right optic nerve in the dorsal aspect of the optic cainal andl a similar one around the left optic nerve in the optic canal. These tumors were removed, but no improvement in the vision ensued postoperatively. No followtip was possible. CASE 3
A 41-year-old womain was seen at the MIayo Clinic in February, 1958 because of blurred vision in the right eye since October, 1957. In December, 1957, anl ophthalmnologist noted edema of the right optic nerve and treatedl her with nicotiinic acid and later with prednisolonie. However, visuial acuity continlued to worsen. Examiinationi showed 4 diopters of papilledema of the right optic dlisk, without hemorrhage, and a normnal left optic disk. Visual acuity was 20/80 in the right eye, improvable to 20/25 with a +1.00 lens, and 20/20, 14/21 in the left eye. The visual field of the right eye was mildly contracted for small targets and the blind spot was enlarged; the field of the left eye was normnal (Fig. 4A). Roentgeniogramiis of the skull, pneumoeincephalogramns, and ventriculogramns gave negative results. An orbital tumor was suspected, but exploration was not advised. One mointh later, the acuity of the right eye had decreased to 20/200, 14/56 and improved to 20/30, 14/21 with a +2.00 lens, indicative of increasiing inldenitation of the posterior pole of the right eye. The papilleclemia was 5 diopters. Exophthalmomiieter readinigs were 18 mnim on the right and 17 min left. The visual field showed only an enlarged blind spot. Orbitonometry inidicatedl increase(l resistance in the right orbit, suggestive of tumor.
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FIGURE 3
(Case 2) Blind right eye. Arcuate field defects, left eye.
In November, 1958, the field of the right eye was more contracted (Fig 4B), and the right disk was still elevated 5 diopters (Fig. 5A). When she returned in April, 1959, the right eye was totally blind and the papilledema measured 4 diopters. There was moderate pallor of the disk and still only 1 mm of proptosis. The opticociliary shunt veins were first visible, dimly seen through the papilledema, in 1966 (Fig. SB). At her last examination in 1972, the right eye was exophthalmic (3 mm), blind, and exotropic (10 degrees). The papilledema measured 11/2 diopters, with numnerous venous shunts on the disk. In 1974, a letter indicated that no change had taken place.
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B:
Further
CASE 4
This patient was 53 years old in March, 1973 when she was first seen at the Mayo Clinic. She had noted a gradual painless decrease in vision of the left eye since December, 1971. She had received oral steroids since August, 1972, without effect on vision.
FIGURE 5
(Case 3)
Right eye with 5 diopters of papilledema. November, 1958. B: Right eye with 4 diopters of papilledema and with visible opticociliary shunt veins, 1966. A:
Nerve Sheath Meningiomas Date: 3-1-73
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(Case 4) X Normal right eye. Greatly contracted field, left eye, March, 1973. B: Pronounced further loss of vision 4 months after operation, June, 1973.
The acuity was 20/14, 14/21 in the right eye and 20/30, 14/21 in the left eye. External examiniationi showed no abnormalities other than an exophthalmomneter reading of 14 mm on the right and 17 mm on the left. There was an afferent defect in the reactions of the left pupil. The fundus of the right eye was normal, but the left disk was edematous (4 diopters). The field of the left eye was generally depressed and that of the right eye was normal (Fig. 6A). Roentgenogramus of the head, orbital tomograins, angiograins, and orbital venograms all gave normal results. Transfrointal exploration showed evidence of high orbital pressure with a thinned orbital roof andl lateral wall. After the orbit was unroofed, a meniingiotheliomatous meninlgiomia was removed from the optic nerve sheath where it extended from behind the globe to the ligamenit of Ziiun. The tumor arose from the attachment of the dura to the clinoid process and from the inferior aspect of the optic canal. Some visioIn was lost durinig the operation. Further visioIn was lost (Fig. 6B) in the left eye during the ensuing 4 months. The left disk was edlematous and was elevated 2'/2 diopters. There was no exophthalmos. In November, 1973, visual acuity was 20/60, the visual field had diminished to 4 degrees, the optic dlisk was pale grade 3 with mild edema, and there was 2 mnm of exophthalmos. The back of the globe was inldente(l about 6 diopters. In December, 1974, acuity of the left eye was 20/100, the disk was pale grade 4, the visual field was reduced to 1 degree, and the papilledema measured 1'/2 diopters. Opticociliary shunts were observed for the first time.
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At the last examination in March, 1976, the left eye had light perception only and the right eye remained normal. No further surgery was advised. CASE
5
A 61-year-old woman was seen at the Mayo Clinic on Aug. 24, 1965, after pallor of the optic disk and a deficit in visioIn of the right eye were discovered. She stated that she had not noted the loss of vision until it was poinited out to her. The vision of the right eye was reduced to finger countinig. The left eve had 20/20, 14/14 visioIn. The right optic disk was pale grade 2; it had ragged marginis and was slightly edematous. The retinal veins were darkenied, ancd there were opticociliarv shunt veins at the 4:00 and the 7:00 o'clock imarginis of the disk (Fig. 7A). There was no proptosis; tensions and movemnents were normal. The visual field of the right eye was depressed and contracted (Fig. 7B). Roentgenograms of the skull showed no abnormality. The patient refused other tests but returned for an examinationi of her eyes in January, 1966, July, 1966, anid July, 1967. At each visit, visioIn of the right eve was worse; and at the last visit, the eye was blind. Roentgenogramns of the skull in July, 1967 showed an osteoma on the upper aspect of the right anterior clinoid process, probably the site of origin of a meninigiomia. Although she refused surgerv, she returned on numilerous occasionis. A computerized tomogram in September, 1975 showed enlargemnenit of the optic nerve (Fig. 8) Other than the development of extreme pallor of the right optic disk, there
has been nio other maniifestationi of continiued growth of the tumior; the opticociliarv shunt veins remainied unchanged, and no proptosis was ineasuredl at any timne. CASE 6
A 47-year-old womilanl was seeni at the Mayo Clinic in Jtuly, 1975 for inivestigationi of chronic fatigue and depressioni. The visioIn of the right eve had begun to deteriorate 13 years previously and within 4 years was blind. At that time, extensive tests showed no abnormiiality and the optic atrophy was thought to be due to drusen. The examiniationi showed a blind right eye and a normnal left eve. The right optic disk was pale grade 4, anid there were opticociliary shunt veinis oni the disk; and the posterior pole of the globe was inidenited about 3 diopters (Fig. 9). Ther-e was 11/2 mm of exophthalmos of the right eye, mild lateral deviationi of the eve, and grade 2 paresis of the medial rectus imuscle. The visual field of the left eve was normial. FIGURE 7 (opposite) (Case 5) A: Right disk with pallor grade 2, slight edemna anid shunits at the 4:00 anid 7:00 o'clock positionis. Large commlluniicating choroidal vein at the 7:00 o'clock but not at the 4:00 positioni. B: Contracted field, right eve. Normal left. August, 1965.
Nerve Sheath Meningiomas
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V.o.S.: /20
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Exaniiner:
/14
V. 0. D.: Counts
fingers
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.4'r
It
FIGUeRE 8
(Case 5) Computerized tomogram showing enlarged right optic nerve, September, 1975.
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FIGURE 9
(Case 6) Pallor grade 4 of right optic disk and shunt veins at the 5:00 and 8:00 o'clock positions.
The patient refused further examination. However, there seemed to be no doubt that this was a meningioma of the optic nerve sheath. CASE 7
A 49-year-old woman was first examined at the Mayo Clinic on Nov. 15, 1976. She had gradually lost the vision of the right eye, beginning in 1966, and it had been blind since 1971. In 1968, the right optic disk was swollen. After extensive tests, including brain scans and angiograms, all of which were negative, she consulted several clinics. The loss of vision was thought to be due to drusen of the optic disk. Exophthalmos of the right eye was first seen in January, 1976. A computerized scan at that time was interpreted as showing hypertrophy of the muscle cone, enlargement of the optic nerve, but no evidence of tumor. This same scan was later reviewed and interpreted as showing proptosis with a thickened right optic nerve near the orbital apex, consistent with meningioma. Examination showed a totally blind right eye and a normal left eye. There was 3 mm of exophthalmos of the right eye and grade 4 pallor of the optic disk, with evidence of previous edema and with opticociliary venous shunts (Fig. 10) at the 6:00 and 8:00 o'clock positions. Exploration was not advised unless the exophthalmos progressed.
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FIGURE 10
(Case 7) Pallor grade 4 of right optic disk, with shunt veini at the 6:00 and 8:00 o'clock positions.
C(ASE 8
A 47-year-old man was examined at the Mayo Clinic on June 8, 1976. The visionl of his right eye began to fail in 1962, and the eye became blind within 3 vears. Extensive investigation at that time failed to reveal a cause. Details of that examinatioin were not available except that in 1962 he had 20/30 visioIn anld papilledema in the right eye, 20/20 vision and a normal left eye, and by 1971, there was no light perception in the right eye. The examination showed a blind right eye with 2 mm of exophthalmos, inild limitation of movement in all directions, and no orbital resistance to retropulsion. There was grade 3 to 4 pallor of the optic disk, with evidences of previous papilledema and prominent opticociliary shunt veins on the optic disk (Fig. 11). Computerized tomography showed enlargement of the optic nerve compatible with a meningioma of the optic nerve sheath or an optic nerve glioma (Fig. 12). Surgery was not advised unless the exophthalmos increased significanitly. The left eve remained normal throughout. CASE 9
A 40-year-old woman was not seen at our clinic, but data were supplied bi a clinic in another state. The patient first sought help in February, 1972 and colmplailled that she had blurred visioIn in the right eye for 9 moniths. The acuity was 20/30 in the right eye and 20/20 in the left eye. The right optic disk was mildly edemna-
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FIGURE 11
(Case 8) Pallor grade 3 to 4 of right optic disk. Shunts at the 3:00, 7:00, and 11:00 o'clock positioins, with huge choroidal communications.
tous, and there were three opticociliary shunt veins on the disk (Fig. 13A). Visual field examination of the right eye showed a dense inferior altitudinal defect and genieralized constriction of the field (Fig. 13B). The examination of the left eye gave norm-al results. Results of tomograms of the optic foramina and roentgenograms of the skull were normnal; the right optic canal and orbit were slightly smncaller than the left. By March, 1972, the acuity of the right eye had decreased to 20/60, and the visual field was worse. Carotid arteriograms and a pneumoencephalogram revealed no abnormalities. Repeated examinations failed to uncover the cause of the condition, and the visioIn remained fairly stable until June, 1973, when a rapid diminution to 20/400 occurred in the right eye. The disk had turned pale, and only a minute residual field of visioIn remlainled in the eye. By Septeinber, 1974, when she returned because of increasinigly severe headaches for 1 month, the right eye had only light perception; and papilledema was observed in the left eye. A radioactive scan and a pneumoencephalogram showed a imass in the anterior midlinie frontal region. Craniotomy proved that this was a psammnomnatous meningioma attached to the crista galli. It was not conttinuous with the imeninlgioma that surrounided the optic nerve. Postoperatively, light perceptioni was present in the right eye; blut a year later, the eve was enitirely blind.
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FIGURE 12
(Case 8) Computerized tomogram showing enlargment of right optic nerve. SUMMARY OF DATA
Of the nine patients, two were men and seven were women. One man and one woman had bilateral meningiomas. Six patients had the right eye affected, one had the left eye, and two had both eyes affected. The ages at onset of the visual deficit among the patients with unilateral disease were 33, 34, 39, 39, 40, 51, and 61 years and among those with bilateral disease, 3 and 6 years. The man who had both orbits involved was said to have gone blind in the left eye at the age of 3 years and his right eye began to fail at the age of 25 years; the woman with bilateral involvement lost vision in her right eye when she was 6 years old and vision of her left eye was first affected at the age of 17 years. Progressive loss of vision to absence of light perception showed a remarkably consistent course, as it occurred in 2, 2 to 3, 3, 3, 3, 4, and 5 years in the seven patients with unilateral defects. The time periods in the patients with bilateral defects were not certain because one of the patients was thought to have lost vision in his left eye as a result of a blow on the head when he was 3 years old, and he became blind in the right eye in 3 years; the other patient lost vision in her right eye during a 10-year period, and no follow-up data on her left eye were available.
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VO.S.:20/20
V.O. D.:20/30
B FIGURE 13
(Case 9) A: Right optic disk with edema and three opticociliary shunt veins. B: Pronounced contracted visual field with arcuate defects, right eye. Left eye is normal.
Hollenhorst et al Prior or concurrent papilledema was documented in the affected eye in six of the nine patients and was questionable in another patient. Papilledema was absent in the two patients with bilateral disease. Proptosis was documented in five patients, being 1, 1½, 2, 3, and 3 mm and always straightforward. Posterior indentation of the globe was noted in five patients, being as much as 6 diopters in one. Only three patients had defects in motility; in all, it was mild. All of the patients had roentgenograms of the skull, and generally, the results were negative. Eight had roentgenograms of the optic canals, and results were negative in all. Seven had cerebral angiograms, and all had normal results. Three had negative pneumoencephalograms; one had a negative ventriculogram; and one had a negative venogram. Skull roentgenograms taken later in case 5 showed an osteoma that was not seen 2 years previously, and in case 9, a frontal lobe tumor developed and was visualized on a pneumoencephalogram. Five patients had computerized tomograms; three tomograms showed the orbital tumors and two failed to do so. Four patients (cases 1, 2, 4, and 9) underwent operation, with removal of all resectable tumor. Although none of the four lost further vision during the surgery, three continued to lose vision during the ensuing years and the fourth was lost to follow-up. Pathologic diagnosis was psammomatous meningioma in three patients and meningiotheliomatous meningioma in the other. The assumption of similar tumors being present in the five orbits that were not explored is open to question, although we have little doubt that they also were meningiomas because findings were so similar. Also, among the five cases of unverified disease, three had positive findings by computerized tomography. The opticociliary shunt veins noted on the optic disks were present in 10 of the 11 eyes involved by these tumors. In one patient (case 2), shunts were observed in the eye with more recent loss of vision but none in the blind eye. There were from one to three shunts, and these could be seen to communicate with large choroidal veins in four patients whose choroidal vessels were visible. All except two patients (cases 3 and 4) had shunts at the first examination, even though the onset of visual symptoms in at least three others (cases 1, 2, and 9) had occurred only within the previous 6 to 9 months. In the other patients, the visual loss had begun between 3 and 14 years previously. 156
DISCUSSION
Opticociliary shunt veins are fairly common in eyes that have suffered from a prior occlusion of the central retinal vein, or a branch of it, as well
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as in eyes with glaucomatous excavation. Also, over the years, there have been many descriptions of various anomalies of the circulation, including opticociliary veins of physiologic type.2,36-10 Venous shunts that develop because of progressive interference with the venous outflow through the central retinal vein in the optic nerve just behind the globe have a different appearance, as they are convoluted and dilated channels that develop from preexisting capillary communications between the retina and the choroid. These occur with optic nerve gliomas, i"' chronic atrophic papilledema, 12 and orbital cysts, 13 as well as with orbital meningiomas. Although the association of acquired opticociliary shunt veins with orbital meningiomas has been known at least since 1893, the recent publications of Frisen, Hoyt, and Tengroth,4 and Spencer5 have revived this knowledge. Meningiomas that arise primarily from the meningeal coverings of the optic nerve within the orbit are relatively rare. Newell and Beaman'4 found only two of 143 patients with meningioma; one patient had 19 mm of proptosis caused by a malignant meningioma, but neither of the two patients had shunt veins. None of the 106 patients with sphenoid ridge meningiomas described by Kearns and Wagener'5 had shunt veins, even those with orbital invasion. Karp and coauthors16 described 25 patients with primary intraorbital meningiomas; there were 21 women and four men with an average age of 31.7 years and a median age of 38 years. Ten patients were less than 20 years of age, and six were less than 10 years of age. Fifteen patients had the right orbit involved, and eight had the left; in two, the affected side was unknown. Ten had papilledema of the affected eye, six had lid edema, and four had limited ocular movement. Only one ofthe ten patients less than 20 years old is alive without recurrent tumor, and five of the ten had to undergo reoperation. Of the 13 patients more than 20 years old, 10 were alive and well 3 to 24 years later. We found no evidence of invasion of the globe in any of our patients, but Coston17 described a patient in whom the meningioma invaded the choroid and retina, and he showed a photograph of a fundus with a typical opticociliary shunt vein. Martin and Schofield's'8 patient was a 3-year-old child with invasion but no shunt veins. Rodrigues and coauthors'9 reported on a case similar to that of Coston's. Walsh20 emphasized the preponderant involvement in females and the association with neurofibromatosis. Moore's2' patient was similar to one of our patients (case 9) in that neither had continuity between the meningioma of the sphenoid ridge and the one involving the optic nerve. He postulated that this may have
Hollenhorst et al been metastasis. We considered that our patient (case 9) had two separately developing meningiomas. In the series of Frisen and coauthors4 the four patients with the triad ofopticociliary veins, disk pallor, and visual loss included two with bilateral defects. Although the report stated that the four were "middle-aged females," 45, 49, 40, and 55 years old, the onset was at age 32 years in the 45-year-old, 40 years in the 49-year-old, 19 years in the 40-year-old, and "blind for years" in the 55-year-old. In these respects, they are similar to our series because seven of our nine patients were female and most were in their 30's or were younger at onset. Three of their patients had mild exophthalmos, as did ours. Frisen and coauthors4 and others5'22 postulated that nearly all patients with meningiomas of the optic nerve sheath initially had edema of the optic disk owing to passive congestion caused by compression of the retrobulbar portion of the central retinal vein and that bypass channels develop within the eye by the dilatation of preexisting capillaries that connect the central retinal vein with peripapillary choroidal veins. As the tumor gradually destroys the optic nerve, the vision is lost and pallor of the nerve head develops, while the shunt veins bypass the central 158
vein.
While this sequence seems to be followed in general, our patients 1, 2, and 9 seem to have developed shunts without edema of the optic disks; and these shunts may have developed before the onset of any symptoms or signs of loss of vision. Of the authors who have written on these tumors, so far as we can determine, only Spencer5 mentioned the indentation or flattening of the globe and the development of hypermetropia in consequence. However, this was observed in five of our patients and probably was overlooked in others of the series. The prognosis for vision was invariably grim for all nine of our patients and seemed to be similarly poor for those reported in the literature to date, whether with or without surgical therapy. The poor outlook for vision probably results from the characteristic growth of the tumor along the meninges, enwrapping the optic nerve and destroying the pial blood supply to the nerves. Surgical removal of the tumor often causes further destruction of the blood vessels and subsequent deterioration of vision. SUMMARY
Nine patiei)ts, including seven women and two men, had meningiomas of the optic nerve sheath. The defect was bilateral in two, in the right
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159 eye in six, and in the left eye in one. Most had edema of the disk, and all had progressive loss of vision to blindness in the affected eye owing to optic nerve atrophy. In 10 of the 11 affected eyes, opticociliary shunt veins developed on the optic disk. Exophthalmos was mild and not more than 3 mm in any patient. Ocular movement was mildly impaired in three patients. Indentation and flattening of the posterior pole of the eye was documented in five eyes. Nine of the eleven eyes went on to blindness; one was worse after operation, and the eleventh was lost to follow-up. Surgical treatment has not been effective in these cases or in those reported in the literature. ADDENDUM
Since this paper was prepared, three additional patients with optic atrophy and associated opticociliary shunt veins have been observed: two had recurrent sphenoid ridge meningiomas with orbital extension, and the third had a blind left eye probably due to huge drusen within the optic disk. REFERENCES 1. Salzmann M: Zur Anatomie der angeborenen Sichel nach innen-unten. Albrecht von Graefes Arch Ophthalmol 39 Part 4:131, 1893. 2. Elschnig A: Ueber opticociliare Gefisse. Klin Monatsbl Augenheulkd 36:93, 1898. 3. Elschnig A: Cilioretinale Gefiisse. Albrecht von Graefes Arch Ophthalmol 44:144, 1897. 4. Frisen L, Hoyt WF, Tengroth BM: Optociliary veins, disc pallor and visual loss: a triad of signs indicating spheno-orbital meningioma. Acta Ophthalmol (Kbh) 51:241, 1973. 5. Spencer WH: Primary neoplasms of the optic nerve and its sheaths: clinical features and current concepts of pathogenetic mechanisms. Trans Am Ophthalmol Soc 70:490, 1972. 6. Hoeg N: Ueber optico-ciliare Vener. Abrecht von Graefes Arch Ophthalmol 55:256, 1903. 7. Duke-Elder S: System of Ophthalmology. Vol 3, Part 2. St. Louis, C. V. Mosby Company, 1963, pp 792-793. 8. Winther E: Abnormal course of retinal blood-vessels of the same type found in a father and his son. Acta Ophthalmol (Kbh) 17:236, 1939. 9. Braune: Ein Beitrag zur Kenntnis optikociliarer Gefisse. Klin Monatsbl Augenheilkd 43:579, 1905. 10. Kraupa E: Beitrage zur Morphologie des Augenhintergrundes. IV. Optikoziliare Arterien, Optikusrandvenen und optikochorioideale Venen. Klin Monatsble Augenheilkd 72:724, 1924. 11. Hoyt WF, Beeston D: The Ocular Fundus in Neurologic Disease: A Diagnostic Manual and Stereo Atlas, St. Louis, C. V. Mosby Company, 1966, p 42. 12. Hedges TR: Papilledema: its recognition and relation to increased intracranial pressure. Surv Ophthalmol 19:201, 1975 13. Miller NR, Green WR: Arachnoid cysts involving a portion of the intraorbital optic nerve. Arch Ophthalmol 93:1117, 1975. 14. Newell FW, Beaman TC: Ocular signs of meningioma. Am J Ophthalmol 45:30, 1958.
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15. Kearns TP, Wagener HP: Ophthalmologic diagnosis of meningiomas of the sphenoidal ridge. Am J Med Sci 226:221, 1953. 16. Karp LA, Zimmerman LE, Borit A, Spencer WH: Primary intraorbital meningiomas. Arch Ophthalmol 91:24, 1974. 17. Costoni TO: Primary tumor of the optic nerve: with report of a case. Arch Ophthalmol 15:696, 1936. 18. Martin VAF, Schofield PB: Meningioma invading the optic nerve. Br J Ophthalnol 41:161, 1957. 19. Rodrigues MM, Savino PJ, Schatz NJ: Spheno-orbital meningioma with optociliary veins. Am J Ophthalnol 81:666, 1976. 20. Walsh FB: Meningiomas, primary within the orbit and optic canal. In Fifth Miami Neuro-ophthalmological Symposium. Vol 5. Hollendale, Florida, Hollendale Press, 1971, pp 240-266. 21. Moore CE: Sphenoidal ridge meningioma with optic nerve metastasis. BrJ Ophthalmol 52:636, 1968. 22. Walsh FB, Hoyt WF: Clinical Neuro-ophthalmology. Vol 3, Third edition. Baltimore, Williams & Wilkins Company, 1969, pp 2080-2083.
DISCUSSION
DR ALAN M. LATIES. Drs Hollenhorst, Hollenhorst and MacCarty are to be congratulated on a careful clinical study of optic nerve sheath meningioma. Although they describe each case in considerable detail, they focus their presentation largely on two questions: the relationship of opticociliary veins to prior edema ofthe optic nerve head and the meaning of the appearance ofan opticociliary vein to vision. Attention is paid to disc edema to test what mnight be called the congestive hypothesis by Frisen, Hoyt and Tengroth. That is, that an opticociliary vein develops when the venous drainage from the nerve head is impeded, such impedence first causing edema. With minor exceptions the authors confirm a congestive hypothesis: specifically, there is clear evidence of disc edema in six of nine patients, partial but suggestive evidence in one of nine and in the other two the history is so long and the eye examination occurred at such a late date that there is a chance that unobserved disc edema might well have been present for a period of time. So far as visual prognosis is concerned, a single word sums it up: dismal. In most reported series and in the present report, an optic nerve meninigioma severe enough to cause disc edema and visible opticociliary shunts, leads to irreversible loss of vision. Interestinigly, the merits of doing a careful clinical review are once again illustrated through the finding of acquired hypermetropia in five patients. Although acquired hypermetropia due to posterior flatteninlg of the globe had beeni previously pointed out by Spencer, in many other instanices it apparently has been overlooked. Lastly, there is a questioni about the precise nature of anl opticociliarv vessel. Under the heading of congeniital abnormnalities, Walsh and Hoyt speak of abnormnal communiicationis between the retinial anid ciliarv systems to include an opticociliarv vein. Similarly, Henkinid and Benjamnini in a recent review of vascular anomialies
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and neoplasms of the optic nerve head (Trans Ophthalmtiol Soc UK 96:418-423, 1976) speak of them in two senses. First, as a congenital anomaly. Second, "the vast majority are developmental resulting from a partial block of the central retinal vein with secondary enlargement of the preexisting capillary network of the optic nierve head. This capillary bed, derived from the posterior ciliary circulationi, would normally drain from the central vein." Somewhat further along, Drs Henkinid and Benjamnini make the point that "opticociliary veins are found mnost frequently after a central retinal vein occlusion and may be the only obvious se(luelae of such an occlusion." In stating that opticociliary veins derive from enilargemenit of a preexisting capillary network, Drs Henkind and Benjamini in fact reiterate what apparently is a consensus concerninig their derivation. However, there is cause to question this consensus; cause instead of wonder whether there mnight not exist in most normal people true venous channels at the optic nerve head draining to the choroid, channlels that under stress can dilate. Certainlv such should be suspected both from clinical and from experimental grounds. A detailed review by Hayreh (BrJ Ophthalmizol 49:626-645, 1965) of many aspects of this matter is available. Equally importanit, Fujino, Curtin and Norton (Arch Ophthal7alol 81:395-406, 1969) showed in the owl monkey that the difference between occlusioin of the central retinal vein at the surface of the optic disc versus its closure as it emerged from the optic nerve posterior to the globe were entirely differenit in consequenice, the former causing a destructive hemorrhagic retinopathy while the latter, although it temporarily impedes venous outflow, vields a far less dIramnatic clinical picture and thus must be moderated by available alterniate routes of drainiage of somewhat greater capacity thani would be afforded by a capillary nietwork. Further evidence alonig this line is available from inijection studies. For inistanice, Aniderson (AmiiJ Ophthalmtiol 20:341-351, 1970) has writtell, "Not all the vessels that extend radially about the optic nerve in the choroid are arteries. Somne of these simall vessels could be traced back as tributaries of a vortex vein. Thus the capillary network of the optic nerve head has both arterial and venious conniiections with the choroidal circulation." Similar observations have been made by WVybar (Amii J Ophthalinol 38:513-518, 1954) and others. In closing, I wanit to thanik Drs. Hollenhorst, Hollenhorst and MacCarty for suppl,ying the paper- to me in plenity of time anid onice agaill to congratulate them for the high quality of their clinical review.
Dmi Fm\xK B. WVALSmm. I congratulate the essayist who bears his father's nlame. I amii (qtuite ssure that his father will remember this mnornlilng as a proud one. The paper was valuable. My experienice with optic nierve sheath meninlgiomiias has been that visual acuity has been lost invariablv. This might occur if the meninlgiomiia was founid to be ectopic anid outside the optic nierve sheath but I do niot have experienice in such a catse. Not related to what l)r Holleinhorst has described we recently have observed a young Imlanl in whomn our nieuroradiologist suggested that pnieumnosinius dilitans well mlight explaini bilateral loss of visioIn.
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An 18-year-old boy was shown to have a tremendous enlargement of the sphenoid sinus with a portion of its protrusion extending superiorly almost to the level of the anterior portion of the sella turcica. Loss of vision was gradual in both eyes of this patient and the X-ray picture I do not have this morning. The protruding sinus was considered for a time as a possible explanation for the progressive bilateral loss of vision. Our experience with pneumosinus dilitans as regards symptomatology was nil. The patient and his parents refused transcranial operation and the boy was returned to the hospital weeks later with the vision reduced to light perception in both eyes. There was pronounced pallor of both discs. On this admission a transcranial operation revealed a meningioma surrounding each optic nerve as it approached the optic canal. These tumors were very small. Tomograms and an EMI-Scan had been described as negative. After operation the patient retained light perception only in each eye. Certainly pneumosinus dilitans was not the proper diagnosis. DR WILLIAM RICHARD GREEN. I would like to raise one point for consideration. Arachnoidal or dural cysts of the optic nerve can simulate the picture of intradural meningiomas within the orbit and should be considered in the differential diagnosis. The presence of an optociliary shunt may be a clue to the presence of such a cyst. When orbital exploration is performed, palpation of the nerve may help to differentiate a dural or arachnoid cyst from a meningioma. Recognition that the lesion is a cyst saves the eye and excision of a portion of the dura in the area of a cyst may result in improvement of vision. DR DAVID COGAN. I realize that the Hoyt-Spencer thesis postulates an obstruction of the retinal vein and collateral drainage by the choroid. Yet these cilioretinal vessels seem to me to differ from the rete mirabile which one sees with central retinal vein obstruction. I wonder, therefore, if they may not represent, in some cases at least, drainage from the tumor itself. I have one pathologic specimen, for instance, where the meningioma had extended into the choroid and might well have utilized such drainage. It would be interesting to know, therefore, whether fluoroangiography showed an early fluorescence of these vessels as would be expected in tumor drainage, or a delayed fluorescence as would be expected with a relative obstruction. DR LAWTON S\trri. This is a very important paper. There is a definite tendency for optic nerve sheath meningiomas to be bilateral. We have had two cases of bilateral optic nerve sheath meningiomas and Dr Glaser has kindly given me notes on a third bilateral case. Interestingly enough, the field defect started temporally in one eye- this then spread until the eye went blind. It then started in the temporal field of the other eye and the last thing left was a nasal- field in the seconid eye. This would immediately make one suspect chiasmal compression. However, arteriograms and air studies were negative in all of these cases for years. The lesions were found by CT scan in only three of the five bilateral cases. Dr Glaser's patient was a 38-year-old woman whose left eye went totally blind at
163 Nerve Sheath Meningiomas age 5 years. At surgery recently when the right eye was involved she was found to have bilateral optic nerve sheath meningiomas. I would not have suspected that one could have an optic nerve sheath meningioma for 33 years with negative contrast studies but that was the report in his case. There have been some reports of efficacy of irradiation therapy on meningiomas. I have treated one patient with a clinical diagnosis of optic nerve sheath meningioma with radiotherapy with improvement from hand movements to 20/70 in the involved eye and she has held this for a year and a half. I believe we will sooIn find that irradiation therapy is the treatment of choice for optic nerve sheath meningiomas, when the diagnosis has been carefully established. I should like to congratulate Dr Hollenhorst and associates on this excellent and important paper. DR ROBERT HOLLENHORST. I wish to thank all the discussors. Doctor Laties, your point about the possible alternative origin of these vessels from other sources than those we have postulated may certainly well be true. I just cannot answer the question. Thank you, Doctor Walsh, for your kind remarks and for your presentation of a very interesting case. Doctor Green's and Doctor Smith's points are very well taken. If the patient has some vision, we do explore the orbit in the hope of restoring some vision. Two of these patients had a blind eye and refusea surgery. If some vision is present, I think one must consider other possible surgically treatable lesions such as an orbital cyst. Doctor Cogan, we have not obtained any ocular specimens; I cannot be certain that some of these cases may not have had invasion of the posterior aspect of the globe. Our fluorescein studies were quite inconclusive although we did not use this method in all cases. I now show four other cases we discovered since the paper was written. This is a patient who had a sphenoid ridge meniingioma. As you can see, there are some small shunt vessels on this disc as well as some residual papilledema and edema residues extending from the disc. The next patient has shunt vessels on the disc; he had a recurrent anterior clinoid meningioma. This next patient had hyaline masses in the disc and a small amount of vision in the eye. Over the course of eight years she developed 3 mm of proptosis, and some small shunt vessels in among the hyaline masses in the optic disc. This last case is a patient who had an optic nerve glioma extending from the back of the globe to the optic chiasm. Shunt vessels were noted on the initial visit along with some edema of the retina and extending to the macula. The next slide shows the same eye following extirpation of the optic nerve glioma. The optic nerve was severed just behind the globe. The shunt vessels have all disappeared. Thank you very much.
