A Case of Intraocular Lymphoma Diagnosed by Subretinal Fluid Biopsy

Although intraocular lymphoma (IOL) mainly has have vitreous opacity and subretinal infiltration, its clinical symptoms are diverse. We report a case of IOL that mainly showed exudative retinal detachment in which analysis of IgH gene rearrangement (AIGHR) of the collected subretinal fluid sample was useful for diagnosis. A 77-year-old woman developed decreased left visual acuity for 1 month. She had been treated for dermatomyositis, diabetes mellitus, and right parotid tumor for 3 years. Visual acuity was 0.1 OD and counting fingers OS. Slit-lamp examination showed grade 4 (Emery-Little classification) nuclear cataract in both eyes and keratoprecipitates and tan vitreous opacity in the left eye. Fundoscopy details were unclear except for a vaguely observable optic nerve head due to yellow-brown vitreous opacity, which we judged as an old vitreous hemorrhage. Phacovitrectomy was performed and almost total retinal detachment was found, except for a part of the superior periphery. Since no retinal break was found and a wide range of thin membrane-like tissue was found on the surface of the retina, the surgeon suspected primary IOL and performed unplanned biopsy. The peripheral vitreous was collected as a sample, and then the subretinal fluid was collected through an intentional break to prevent mixing with other fluids. The subretinal strand was gently removed and collected. Cytology showed class III, the IL10/IL6 ratio was low, and AIGHR was positive. Postoperatively, fundus autofluorescence showed no abnormality, no leakage was observed on fluorescein and indocyanine green angiography, and the location of typical infiltration lesions under the retina was unclear. There were no positive findings on systemic examinations and a diagnosis of primary IOL was made. The main symptoms of this case were vitreous opacity and exudative retinal detachment, and AIGHR using subretinal fluid was useful for diagnosis.