| OCR Text |
Show /. Clill. Nt'llro-ol'iltllllllllo/. 5: LJ()-Y.J, ILJH5 © 1985 Raven Press, New York Atypical Visual Prognosis with an Optic Nerve Glioma LARRY P. FROHMAN, M.D. FRED EPSTEIN, M.D. MARK J. KUPERSMITH, M.D. Abstract A 13-year-old girl presented with a I-year history of gradual decline of vision in her right eye. She was diagnosed by clinical examination and computed tomographic scan as having a right optic nerve glioma. While awaiting surgery, she experienced spontaneous improvement of her symptoms. Four years after the onset of symptoms, the Snellen acuity, color testing, and visual fields have returned to normal, while the computed tomographic appearance of the tumor is essentially unchanged. Possible mechanisms for such a fortuitous outcome are discussed. In the last few decades, as our understanding of the biology of gliomas of the anterior visual pathway has grown, so has controversy regarding the appropriate therapy for these tumors.!-? While most accept these lesions as benign hamartomas,3 there are occasional lesions that behave more aggressively. Nonetheless, in the era of computed tomography (CT), most physicians would clinically and radiologically follow an optic nerve glioma if there were no sign of impending chiasmal involvement or unmanageable proptosis. A recent report has used third- and fourth-generation high-resolution CT scans to clarify the radiologic criteria for the diagnosis of optic nerve glioma. 8 This may, in many ca.ses, obviate the need for biopsy expressed 10 some of the earlier reviews.V> We report our experience in a patient in whom serial observation of the tumor had a fortuitous outcome. Case Report A B-year-old girl was referred because of 1 year of intermittent blurring of vision in her From the Departments of Ophthalmology (L.P.F., M.j.K.). Neurosurgery (F. E.), and Neurologv (M.j.K.). New York University School of Medicine, New York. New York. Write far reprillts to: M. j. Kupersmith, M.D.. 530 First Ave., Suite 3B, New York, NY 10016. U.S.A. 90 right eye. Whereas she did not know whether it had progressed, serial vision screenings at school and by her ophthalmologist had revealed a gradual decline in Snellen acuity over 1 year. There were no other symptoms. General medical history and examination were unremarkable. She began menstruating at age 10 and continued to have normal menses. A CT scan had been done (Figs. 1a and 1b) and showed a diffusely enlarged right optic nerve from the orbital apex to the globe and through a widened optic canal. Initial neuro-ophthalmic examination in March 1981 revealed best-corrected Snellen acuity of 20/200 00 and 20/20 OS. American Optical pseudoisochromatic color plates were 1/6 in the right eye and 6/6 in the left eye. Arden gratings were consistent with decreased contrast sensitivity in the right eye, with sparing of the lower spatial frequencies. The left eye was normal. The visual field was normal in the left eye, and there was a dense central scotoma and an enlarged blind spot in the right eye (Fig. 2, top). The pupils were 4 mm round and reactive to light in both eyes, with a right afferent pupillary defect. The extraocular versions, sac~ ades, pursuit, and optokinetic nystagmus were 1Otact. The anterior examination was normal, and exophthalmometry revealed no proptosis. The tundus examination of the right eye showed gray-white pallor of the inferotemporal disc, with ruts in the inferotemporal nerve fiber I~yer a~d ede~a of the superior and nasal portions ot the diSC and nerve fiber layer. There were no spontaneous venous pulsations, but the veins did collapse with gentle digital pressure. The left fundus was normal. . ~hen .admitted to the hospital for surgical exCISion ot the optic nerve glioma a few weeks later, the patient's vision had improved to 20/80 00. ~~cause o~ this spontaneous improvement, a deCISIOn to discharge her and follow up with frequent examinations was made. One month later, her vision was 20/60 +2 in the right eye. The color testing and pupillary responses were unchanged. The visual field in the left eye was Frohman et al. Figure 1. Serial CT scans of the optic nerves. (a and b) March lY81-Note the enlarged optic nerve and widened right optic canal. (c) August 1982-Note "kinking" of right optic nerve. (d) Septembt>r 1984-Essentiallv unchanged from prior e:l.aminalion. the same, but the right eye now showed a small paracentral arcuate scotoma (Fig. 2, middle). The fundus of the right eye showed white temporal pallor with a diffusely thinned and edematous nerve fiber layer. Four months later, the Snellen acuity was 20/50 00. One year after her initial presentation, the Snellen acuity was 201 40 00 and 20/20 as, with color testing improving to 4/6 corrected in the right eye. The June 1985 visual field now showed a small paracentral scotoma to a 2-mm whitt' test object (Fig. 2, bottom). The afferent pupillary defect was present but less obvious. The fundus revealed moderate temporal pallor with diffuse thinning of the nerve fiber layer, more noticeable temporally. Spontaneou's venous pulsations were present and there was no nerve fiber layer or disc edema. A CT scan done in September 1982 91 Atvpic,ll Visual Prognosis in Uplk Nl'rVl' ClioIlla td Figure 1. Ctl/lllIl/l<'d showed a fusiform lesion extending to the suprasellar cistern (Fig. Ie). Examination in September 1983 revealed a Snellen acuity of 20/20 au. The visual fields were full to a 2-mm white test object and the color plates were 6/6 au. A 1+ right afferent pupillary defect persisted. When she was last examined in September 1984, the patient's vision was 20/15 au with full fields to a I-mm 92 white test object. A CT scan done at that time was unchanged from the prior study (Fig. Id). Discussion Whereas there have been a few reports of stable vision or spontaneous improvement of vision in patients with chiasmal gliomas,2,9 we found in the literature only two cases of patients Journal of Clinical Neuro-ophthalmology L L 20/20 L 20/20 R 20/200 R 20/60+2 R 20/40 Frohman et al. June 1985 Figure 2. Serial visual fields. Top: March I<)HI. Middle: Mav ILJHI. Bottom: April ILJH2. In all three fields. solid lines and solid shading rl'f'resl'nt (c'sting with ,1 S-mm white tl'st"hjl'd. and dotted lines and cross-hatching represent tesling with .1 2-ml11 white tl'St ,>hil'ct. All fields done at a I-m test distance. 93 Atypical Visual Prognosis in Optic Nerve Glioma with an optic nerve glioma who demonstrated visual improvement without surgery or radiation therapy. Wright t't aI.l> reported a case of a child with an optic nerve glioma whose vision rt'sponded to patching therapy alone. Anderson t't aI. II reported the case of a child with an optic nerve glioma that was diagnosed 6 years after a 2-wt'l'k episode of decreased vision of unknown etiology. There is also a case report of a child who presented with a I-month history of headaches and who was found to have proptosis and papilledema of the right eye, with best-corrected Snellen acuity of 20/20-2 00 and 20/25 + 1 as, and a histologically verified right optic nerve glioma. llJ This child never had loss of vision. We believe that this is the first documented case report of a tumor that meets the criteria for CT diagnosis of an optic nerve glioma as reported by Jakobiec et aI.K that has shown dramatic recovery of visual function without surgery or radiation therapy. As the lesion certainly did not regress on the CT scan, the mechanism by which the tumor's effect on the optic nerve fluctuates is not clear. Goodman et aI. llJ has shown in his case of a large optic nerve glioma with normal vision that, although there was demyelinization present, the architecture of the nerve was preserved. Our case proves that the presence of an optic nerve glioma does not de facto rule out the return of visual function. A possible mechanism for fluctuation of vision is that as myxomatous changes are known to occur within optic nerve gliomas,3.1 and as the quantity of the hydrophilic extracellular mucus can vary relatively rapidly,11 perhaps the water content of these tumors varies and causes fluctuating compression and dysfunction of the remaining neural elements. Furthermore, in a child of this age, perhaps some endocrine function allows for variable vascular engorgement of the glioma. We feel that this case reaffirms the view that in a painless eye with a tumor that mef'ts the CT criteria for the diagnosis of an 94 optic nerve glioma, regardless of the visual acuity, repetitive neuro-ophthalmologic examination and periodic CT scanning is a viable alternative to surgery or radiation therapy. References 1. Dodge, H. W., Love, J., Grafton, McK., Craig, W., Dockerty, M. B., Kearns, T. P., Holman, C B., and Hayles, A B.: Gliomas of the optic nerve. Arch. Neural. PSlfchiatrlf 79: 607-621,1958. 2. Tym, R.: Piloid gliomas o(the anterior visual pathways. Br. f. Slag. 49: 322-331. 1961. 3. Hoyt, W. F., and Baghdassarian, S. A.: Optic glioma of childhood: natural history and rationale for conservative management. Br. f. Ophthalmol. 53: 793-798, 1969. 4. Miller, N. R., Iliff, W. J., and Green, W. R.: Evaluation and management of gliomas of the anterior visual pathways. Brain 97: 743-754, 1974. 5. Oxenhandler, D. C, and Savers, M. P.: The dilemma of childhood optic gliomas. f. Neurosurg. 48: 34-41, 1978. 6. Wright, J. E., McDonald, W. 1., and Call, N. B.: Management of optic nerve gliomas. Br. f. Ophthalmol 64: 545-552, 1980. 7. Rush, J. A., Younge, B. R., CampbelL R. J., and MacCarthy, C. S.: Optic glioma: long-term follow-up of 85 histopathologically verified cases. Ophthalmology 89: 1213-1219, 1982. 8. Jakobiec, F. A., Depot, M. J., Kennerdell, J. S., et al.: Combined clinical and computed tomographic diagnosis of orbital glioma and meningioma. Ophlhalmologl/91: 137-155,1984. 9. Aarabi, B., Long, D. M., and Miller, N. R.: Enlarging optic chiasmal glioma with stable visual acuity. Sl/rg. Nel/rol. 10: 175-177,1978. 10. Goodman, S. J., Rosenbaum, A L., Hasso, A, and Itabashi, H.: Large optic nerve glioma with normal vision. Arch. Ophllwlmol. 93: 991-995, 1975. 11. Anderson, D. R., and Spencer, W. H.: Ultrastructural and histochemical observations of optic nerve glioma. Arch. 0l'hthalmol. 83: 324335, 1970. Journal of Clinical Neuro-ophthalmology |
