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Show Journal of Clinical Neuro- ophthaimoioxy 12( 4): 238- 241, 1992. Asymptomatic Unilateral Papilledema in Pseudotumor Cerebri Mitchell B. Strominger, M. D., Gerald B. Weiss, M. D., and Mark F. Mehler, M. D. © 1992 Raven Press, Ltd., New York A 32- year- old asymptomatic woman was found to have unilateral papilledema on routine ophthalmological examination. Subsequent visual field, neuroimaging, and cerebrospinal fluid examinations were consistent with the diagnosis of pseudotumor cerebri. This case demonstrates that pseudotumor cerebri may present as unilateral papilledema in any asymptomatic patient and illustrates the need for thorough neuro- ophthalmological evaluations to allow early detection of cases with atypical presentations to increase the efficacy of therapeutic intervention and prevent progressive visual loss. Key Words: Pseudotumor cerebri- Asymptomatic unilateral papilledema From the Saul R. Korey Department of Neurology and the Henkind Ophthalmological Institute, Albert Einstein College of Medicine, and the Neurological and Ophthalmological Services, Bronx Municipal Hospital Center, Montefiore Hospital Medical Center and the J. D. Weiler Hospital of the Albert Einstem College of Medicine, Bronx, New York, U. S. A. Address correspondence and reprint requests to Dr. Mark F. Mehler, Department of Neurology ( F, G- 9), Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA. 238 Pseudotumor cerebri ( PTC) almost always presents with bilateral papilledema and such clinical symptoms as headaches, transient visual obscurations, and diplopia. Isolated case reports of PTC have described the presence of unilateral papilledema or even the absence of papilledema ( 1- 8). Mechanisms used to explain these associations have included obstruction to the transmission of cerebrospinal fluid ( CSF) pressure to the optic nerve head by congenital anomalies of the optic nerve sheath, compression from tumor, and adhesions as a consequence of inflammation. We describe a case of PTC that presented with the unusual combination of unilateral papilledema without clinical symptoms of increased intracranial pressure. The recognition of this latter entity has important diagnostic and therapeutic implications. CASE REPORT A mildly obese 32- year- old woman was noted on routine examination by an optometrist to have " swelling" of the right optic nerve disk in 1988 and was advised to see an ophthalmologist for further evaluation. Specifically, the patient denied experiencing headaches, visual complaints, or other neurological symptoms. Her medical history was remarkable for migraine headaches ( ages 18 to 22) and gestational diabetes mellitus. Two years later she returned to the optometrist because her child needed corrective lenses. At this latter time, the optometrist renewed his suggestion that the mother undergo a complete ophthalmological evaluation, and, as a result, she was examined at the Montefiore Hospital Medical Center Ophthalmology Clinic. She had remained asymptomatic during the intervening period. On examination at the ophthalmology clinic in April of 1990 unilateral papilledema of the right eye was noted. Neuro- A ASYMPTOMATIC UNILATERAL PAPILLEDEMA FIG. 1. ( A) Funduscopic examination of the right eye showing swelling of the right optic nerve. ( B) Funduscopic examination of the left eye showing a normal- appearing left optic nerve. This finding contrasts with that shown in Figure A. 239 ophthalmological consultation revealed visual acuity of 20/ 25 au, normal pupillary responses, and full color vision by Ishihara test plates. Anterior segment examination was normal and intraocular pressures were 13 mmHg in both eyes. Examination of the fundus was remarkable for swelling of the right optic nerve ( Fig. 1A) and a normalappearing left optic nerve ( Fig. 18). Visual field testing by Humphrey program 24- 2 revealed a slightly enlarged blind spot in the right eye. The visual field of the left eye was normal. A subsequent fluorescein angiogram demonstrated early hyperfluorescence on the surface of the right optic nerve, which persisted throughout the angiogram, consistent with unilateral optic nerve head swelling ( Fig. 2A, B). The patient was sent to the Bronx Municipal Hospital Center Neurology Clinic for further diagnosis and management. Computed tomography ( CT) scan of the head and orbits revealed a small ventricular system with generalized cerebral sulci effacement, an empty sella with erosion of the floor and symmetrical thickening of the optic nerves. There were no structural mass lesions, hemorrhages, or infarcts seen. Initial laboratory studies, including blood cellular indices, ESR, routine chemistries, endocrinologic studies ( TFT, cortisol), serum RPR and Lyme titers were normal. Lumbar puncture performed on admission revealed an opening pressure of 360 mmH2 0, closing pressure of 130 mmH20, and normal cell counts and chemistries. She was begun on acetazolamide, 250 mg orally, every 6 hours. The patient was followed at regular 4- to 6- month intervals by full neuro- ophthalmological examination, Humphrey visual field testing and fundus photography. Most recently in January 1992 she remained clinically asymptomatic. Visual field testing by Humphrey program 24- 2 revealed no change in the slightly enlarged blind spot in the right eye, and the left eye was normal. Examination of the fundus showed chronic swelling of the FiG. 2. ( Aj Fl'uorescem dr1gllJgraphy or ine rlghi eye ihai demonstrates early hyperfluorescence of the surface of the right optic nerve, which persisted throughout the angiogram. ( B) Fluorescein angiography of the left eye in the late phase demonstrates the absence of abnormal hyperfluorescence. I Cli" Neuro- oplrthall/ lol, Vol. 12, No. 4, 1992 240 A M. B. STROMINGER ET AL. FIG. 3. ( A) Interval funduscopic examination of the right eye showing chronic swelling of the right optic nerve head with a small optociliary shunt vessel. ( B). Interval funduscopic examination of the left eye showing a normal appeanng left optiC nerve. B right optic nerve head with a small optociliary shunt vessel that, in retrospect, was present in April 1990 ( Fig. 3A). The left optic nerve appeared normal ( Fig. 3B). A high- resolution CT scan of the orbits and brain with contrast was performed to rule out a progressive unilateral optic sheath meningioma. The study again demonstrated symmetrical thickening of both optic nerves and diffuse effacement of the sulci consistent with a diagnosis of pseudotumor cerebri ( Fig. 4). The patient was maintained on acetazolamide, 250 mg orally, every 6 hours. DISCUSSION The most common presenting symptom in patients with pseudotumor cerebri is headaches occurring in more than 90% of cases. Visual symptoms, such as transient visual obscurations and horizontal diplopia, occur in 35% to 70% of pa- FIG. 4. Interval computed tomography scan of the orbits with contrast, demonstrating symmetrical thickening of both optic nerves. tients. Other less common symptoms include nausea and vomiting, dizziness, vertigo, and tinnitus ( 8). While the vast majority of PTe patients present with bilateral papilledema, there have been isolated case reports of unilateral papilledema ( 1- 5) and even less frequently the absence of papilledema ( 8). In patients with unilateral papilledema, correlative symptoms may be as mild and innocuous as dull pain behind the affected eye and difficulty focusing ( 1,3). Approximately 90% of the patients with documented unilateral papilledema have been obese, and all have had symptoms or signs indicative of increased intracranial pressure. These patients improved markedly with institution of different therapeutic regimens: diet, corticosteroids, acetazolamide, serial lumbar punctures, optic nerve sheath decompression, or a combination of the above. Etiologic mechanisms used to account for the unilateral papilledema in PTC have included an acquired or congenital abnormality of the optic nerve sheath on the side of the normal appearing disk, which can theoretically occlude the communicating subarachnoid space between the orbit and intracranial cavity. Increased intracranial pressure in association with unilateral optic atrophy or optic disk dysplasia are other settings in which unilateral papilledema has been observed. The occurrence of PTC in a clinically asymptomatic patient with unilateral papilledema and abnormal visual fields has not previously been described. This case demonstrates the importance of thorough neuroophthalmologic and neuroradiologic evaluations in asymptomatic patients with unilateral ( or bilateral) papilledema to allow for early identification of patients with PTC, so that timely therapeutic intervention can be instituted to preserve residual visual function. ASYMPTOMATIC UNILATERAL PAPILLEDEMA 241 REFERENCES 1. Sher NA, Wirtschafter }, Shapiro SK, Crispin S, Shapiro I. Unilateral papilledema in " benign" intracranial hypertension ( pseudotumor cerebri). lAMA 1983; 250: 234Er7. 2. To KW, Warren FA. Unilateral papilledema in pseudotumor cerebri. Arch Ophthalmol 1990; 108: 644- 5. 3. Kirkham TH, Sanders MD, Sapp GA. Unilateral papilledema in benign intracranial hypertension. Can I Ophthalmol 1973; 8: 532--- S. 4. Sedwick LA, Burde RM. Unilateral and asymmetric optic disc swelling with intracranial abnormalities. Am I Ophthalmol 1983; 96: 484- 7. 5. Bruntse E. Unilateral papilledema in neurosurgical patients. Acta OphthalmoI1970; 48: 759- 64. 6. Lipton HL, Michelson PE. Pseudotumor cerebri syndrome without papilledema. lAMA 1972; 220: 1591- 2. 7. Scanarini M, Mingrino S, d'Arella D, Della Corte V. Benign intracranial hypertension without papilledema: case report. Neurosurgery 1979; 5: 37Er7. 8. Walsh FB. Unilateral Papilledema. In: Miller NR, ed. Walsh Qlld Hoyt's clinical neuro- ophthalmology, Vol 1, 4th ed. Baltimore: Williams & Wilkins, 1982, 187- 9. / Clill Neuro- ophthalmol, Vol. 12, No. 4, 1992 |
