Purpose: To assess the contribution of vitreous cytologic evaluation to the diagnosis of clinically undiagnosed vitritis.
Design: Retrospective chart review and database study.
Participants: Two hundred seventy-eight eyes of 255 patients who had diagnostic vitrectomies.
Methods: We performed a retrospective review of all patients who had vitreous cytology specimens between October 1990 and October 2005 at Vancouver General Hospital. We reviewed the patient charts to obtain the results of microbial and other laboratory testing and to determine the follow-up course.
Main outcome measures: Categories of vitreous cytology specimen results and final clinical diagnosis in patients who had diagnostic vitrectomy specimens.
Results: We reviewed vitreous cytology results from diagnostic vitrectomies in 278 eyes of 255 patients. One patient had 3 diagnostic vitrectomies, 21 patients had 2 procedures, and 233 patients had a single procedure. We categorized the results of vitreous cytologic examination into 6 major categories: acute inflammation consistent with endophthalmitis (n = 33), primary intraocular lymphoma (PIOL; n = 14), granulomatous inflammation (n = 41), mixed chronic nonspecific inflammation (n = 76), hypocellular specimens (n = 50), and miscellaneous specimens (n = 64). We determined that cytologic diagnosis aided or confirmed a clinical diagnosis, or ruled out PIOL, in 126/228 (55.3%) specimens where patients were not lost to follow-up.
Conclusions: Cytologic analysis of vitreous specimens in clinically undiagnosed vitritis is a useful procedure, particularly in the diagnosis of endophthalmitis and PIOL. It is also helpful in confirming granulomatous, nonspecific, and miscellaneous clinical diagnoses and in ruling out PIOL. In this series, it helped to suggest or confirm a diagnosis in the majority of our specimens.