E Kim, et al. A CASE OF PIOL TREATED BY INTRAVITREAL MTX A B C Fig. 1. (A) Fluorescein angiography; some perivascular dye leakage, disc hyperfluorescence and granular patterns of scattered hypofluorescent and hyperfluorescent spots are seen in the right eye. (B) Visual field of the right eye; considerable peripheral constriction is seen in pattern deviation. (C) OCT of the right eye; small RPE humps are seen. mined by pattern visual evoked potentials (VEP). Prominent suppression of the central signal was noted in multifocal ERG of the right eye compared with that of the left eye (Fig. 2). After three months of failure to follow-up, the patient’s BCVA decreased to no light perception (NLP) OD and 20/200 OS, and active panuveitis was observed in the right eye. Shallow retinal detachment, vitreous debris and chorioretinal thickening were detected by ultrasonography. The left eye had mild uveitis and multiple vitreous seedings. It showed a granular pattern and leakage in angiography, small RPE humps in OCT, and con- siderable visual field constriction (Fig. 3). A thorough systemic evaluation was performed, but there was no evidence of int- racranial or visceral involvement, and the hematologic exam was nonspecific except for an elevated erythrocyte sedimen- tation rate. Mega-dose intravenous steroid therapy was carried out, followed by diagnostic vitrectomy with retinal biopsy of the right eye. Diffuse large malignant B-cells with strong immunoreac- tivities in CD20 immunostaining were seen in the preretinal membrane biopsy specimen otherwise, no abnormal cells were obtained from the vitreous biopsy (Fig. 4). Intravitreal injec- tions of MTX (800 μg/0.1 ml in the right eye, 400 μg/0.05 ml in the left eye) were performed twice weekly for one month, once weekly for the next month, once every two weeks for the following month, followed by nine monthly injections. During the treatment, punctuate epithelial erosions and vortex kerato- pathy developed, but they subsided completely with topical in- stillation of 0.003% leucovorin eye drops and lubricants (Fig. 5). The final BCVA was NLP OD, 20/20 OS, and both eyes were free from malignant cells in vitreous biopsy six months later. The granular pattern on fluorescein angiography was persistent but there was no dye leakage (Fig. 6). In the left eye, the visual field constriction was slightly improved, and the small RPE humps in OCT had disappeared. Although P1 latency was mar- kedly delayed in the right eye compared with that of the left eye, the P1 amplitudes showed a minimal difference in flash VEP. The EOG Arden ratio was 0.9604 OD and 1.231 OS. The amplitude of b waves was markedly decreased in a scotopic ERG of the left eye the photopic ERG response, oscillatory po- tentials and 30 Hz flicker response were relatively well preser- ved, with ERG waves being flat in the right eye. The patient was free of intracranial and ocular recurrence until six months later. No ocular complications except minimal opacities of the crys- talline lenses were noted in both eyes. 211