RÉSUMÉ
PURPOSE: To determine the diagnostic and functional yield of vitrectomy in patients with uveitis of unknown origin. METHODS: A single-centered retrospective study was performed on patients who underwent a diagnostic vitrectomy for uveitis in the Department of Ophthalmology of the Nancy University Hospital from January 2011 to December 2016. Vitreous samples were analyzed in the cytology laboratory by cytological and immunohistochemical techniques, and in the microbiological laboratory by culture and bacterial, fungal and viral PCR, depending on clinical findings. Preoperative and one- and six-month postoperative visual acuity were collected and compared. RESULTS: Thirty-four patients (39 vitrectomies) were included. Vitreous testing led to a diagnosis in 14 out of 39 cases (36 %): 10 intraocular lymphoma, 2 amyloidosis, 1 CMV retinitis, and 1 choroidal metastasis of cutaneous melanoma with vitreous dissemination. Vitrectomy was negative in 20 patients. Visual acuity improved from 1.2±0.7 logMAR preoperatively to 0.8±0.7 logMAR at 1 month (p<0.001) and 0.9±0.8 logMAR at 6 months (p=0.054). CONCLUSION: In our study, diagnostic vitrectomy and vitreous fluid analysis were useful to diagnose uveitis of unknown origin, most of which were found to be intraocular lymphomas. Visual acuity improved for the majority of patients. Diagnostic vitrectomy with appropriate vitreous analysis related to clinical examination must be considered in the evaluation of uveitis of unknown origin.