| OCR Text |
Show Journal of Neum- Ophtluilmoloxy 19( 1): 10- 11, 1999. © 1999 Lippincoll Williams & Wilkins, Inc., Philadelphia Cerebral Metastasis Presenting With Altitudinal Field Defect Richard S. B. Newsom, M. D., Peter Simcock, F. R. C. O. and Haddi Zambarakji, F. R. C. O. A 75- ycar- old man presented with a unilateral inferior altitudinal visual field defect and a history of weight loss and night sweats. The acuity in the affected eye was 20/ 200, otherwise his ocular examination was normal. Neuroimaging demonstrated a post- fixed chiasm, with a frontal metastasis compressing the intracerebral portion of the optic nerve. A chest x- ray showed classical cannon ball lesions, secondary to malignant melanoma. This is the first case report of an intracerebral tumor producing an inferior altitudinal field defect. Key Words: Altitudinal field defect- Metastasis- Cerebral. Altitudinal field defects are commonly associated with anterior ischemic optic neuropathy ( ANION) ( 1), optic neuritis ( 2), optic disc drusen ( 3), low tension glaucoma ( 4), and chronic papilledema. We report a case of inferior altitudinal field loss resulting from intracerebral metastasis. CASE REPORT A 75- year- old man presented with a 3- day history of rapidly progressing, painless visual loss in his left eye. The right eye was amblyopic from childhood strabismus. There was no periorbital or temporal discomfort, but he was lethargic and on questioning reported recent night sweats and weight loss. He had psoriasis, controlled with Methotrexate ( 2.5 mg/ week) ( Pharmacia, U. K.) and psoralen and ultraviolet- A. A malignant melanoma had been removed from his nose 2 years previously. On examination he was plethoric and perspiring, the right visual acuity was 20/ 120, and the left acuity was 20/ 200. There was an afferent pupil defect in the left eye with loss of color vision; visual field to confrontation showed an inferior altitudinal field defect which was confirmed on computerized perimetry ( Fig. 1). There was no proptosis and cranial nerve function was normal. Manuscript received February 15, 1996; accepted August 20, 1996. From the Department of Ophthalmology ( R. S. B. N), St. Thomas' Hospital, Lambeth Palace Road, and Department of Ophthalmology ( P. S., H. Z.), Charing Cross Hospital, Fulham Palace Road, London, United Kingdom. Address correspondence to Mr. R. S. B Newsom, Dept. of Ophthalmology, St. Thomas' Hospital, Lambeth Palace Road, London SE1 7EH, U. K. The anterior segments were healthy, and fundoscopy showed no evidence of optic disc or vascular abnormality in either eye. Computerized tomography of the brain showed multiple intracerebral metastasis, with a large deposit in the left frontal lobe compressing the left optic nerve ( Fig. 2) with a post fixed optic chiasm. A chest x- ray showed cannonball metastasis with pleural effusion ( Fig. 3). The patient was treated with high dose systemic dose steroids and fractional cerebral radiotherapy ( 600 GcY). Visual acuity improved to 20/ 60 in the left eye with a concomitant improvement in the visual field. A fine-needle biopsy of a lung lesion showed malignant melanoma, also present in the brain metastasis. DISCUSSION Traustason et al. ( 1) found 55% of patients with ANION had altitudinal field defects. The superior fibers are usually affected, giving an inferior field defect; this may be because of the anatomy of the circle of Zinn ( 5) or anastomotic supply to the inferior optic nerve from the ophthalmic artery ( 6). This propensity is in contrast to intracerebral tumors such as sphenoidal ridge meningioma which cause compression of inferior fibers and therefore superior field defects ( 7). In our case compression occurred from above producing an inferior altitudinal field defect, the sudden progression possibly relating to intratumor hemorrhage. Although ANION was excluded by the retinal findings, this case demonstrates that inferior altitudinal field defects are not synonymous with ANION and altitudinal field defects in the presence of normal fundi are an absolute indication for neuroimaging. REFERENCES 1. Traustason OI, Feldon SE, Lccmaster JE, Weiner JM. Anterior ischemic optic neuropathy: classification of field defects by Octopus automated static perimetry. Graefes Arch Clin Exp Ophthalmol 1988; 226: 206- 12. 2. Keltner JL, Johnson CA, Spurr JO, Beck RW. Baseline visual field profile of optic neuritis. The experience of the optic neuritis treatment trial. Optic Neuritis Study Group. Arch Ophthalmol 1993; 111: 231- 4. 3. Hoover DL, Robb RM, Petersen RA. Optic disc drusen in children. J Pediatr Ophthalmol Strabismus 1988; 25: 191- 5. 10 CEREBRAL METASTASIS II PATTERN DEVIATION s?_ a PfiTTERN DEVIATION : re S • P • • m* * » • & FIG. 1. The Humphries 30- 2 visual field of the left eye. The total deviation ( a) and the pattern deviation ( b) are shown. The fields demonstrate an inferior altitudinal field loss ( mean deviation - 21.6 dB, P < 0.5). There were 2/ 17 fixation losses and 3/ 9 false negative errors. ( Note: The data from the amblyopic right eye were unreliable.) FIG. 2. Computerized tomography of the brain demonstrating a mass in the left frontal lobe compressing the left optic nerve and a metastasis in the temporal lobe. ( Note: A post fixed chiasm is not demonstrated in this cut.) FIG. 3. An x- ray of the chest demonstrating cannonball metastasis with early pleural effusion and lymphadenopathy. 4. Drance SM. The visual field of low tension glaucoma and shock-induced optic neuropathy. Arch Ophthalmol 1977; 95: 1359- 61. 5. Olver JM, Spalton DJ, McCartney AC. Microvascular study of the retrolaminar optic nerve in the possible significance in anterior ischaemic optic neuropathy. Eye 1990; 4: 7- 24. 6. Onda E, Ciofi'i GA, Bacon DR, Michael Van Buskirk H. Microvas-culature of the human optic nerve. Am J Ophthalmol 1995; 120: 92- 102. 7. Jams GD, Feldon SE. Clinical and computed tomographic findings in the Foster Kennedy syndrome. Am J Ophthalmol 1982; 93: 3I7- 22. J Neitm- Oplilluilnml, Vol. 19, No. I, 1999 |
