Use of Diagnostic Vitrectomy in Eyes With Uveitis of Unknown Etiology

Abstract

Purpose: : To determine the ability of diagnostic pars plana vitrectomy (PPV) to establish a diagnosis, change treatment regimen, or improve visual acuity in eyes with uveitis of unknown etiology.

Methods: : Retrospective case series of patients who underwent diagnostic PPV. Inclusion criteria included uveitis with incomplete response to conventional therapy, or with a suspected infectious or malignant cause and a negative systemic evaluation. Undiluted and diluted vitreous samples were obtained using a 3 cc syringe connected directly to the vitrectomy instrument. Vitreous specimens were processed by microbiology, cytology, and flow cytometry.

Results: : Forty–one patients (41 eyes) were included in this study. The median age of these patients was 62 years (range 4–87) and 48.8% were male. Time from presentation to PPV was 530 days ±1146. Uveitis types found were 10 intermediate, 8 posterior, and 23 panuveitis. Suspected diagnoses were 21 malignant, 16 infectious, and 4 inflammatory. PPV yielded a diagnosis in 6 cases (14.6%). Of the 21 cases in which malignancy was suspected, PPV yielded a diagnosis in 4 cases (19%). Of the 16 cases in which infection was suspected, two specimens (12.5%) had microbiologic growth, one P. acnes and the other Aspergillus flavus. PPV either confirmed or ruled out the pre–operative diagnosis in 29 cases (70.7%). PPV guided treatment in 18 cases (43.9%) in the following manner: chemotherapy started (3), antimicrobial therapy started (2) or stopped (7), topical steroids stopped (4), intravitreal triamcinolone given (1), and methotrexate started (1). Mean logMAR preoperative and postoperative visual acuity corresponded to 20/133 and 20/87, respectively (p=0.18). Vision improved after vitrectomy in 27 patients (65.9%), 15 of whom gained 3 or more lines of visual acuity. Vision was not affected by PPV in 4 patients. Causes for loss of vision in 10 patients included cataract, foveal chorioretinal scar, occlusive vasculitis, optic neuropathy, hypotony, and enucleation. PPV was complicated by retinal detachment in only one patient.

Conclusions: : This study demonstrates that diagnostic PPV is effective in diagnosing malignancy, ruling out infection, and guiding management in a large number of uveitis cases of unknown cause.

Keywords: vitreoretinal surgery • inflammation • clinical (human) or epidemiologic studies: outcomes/complications