Diagnostic Yield of Vitreous Biopsy in Sarcoid Uveitis

"Three-port, 20-gauge pars plana vitrectomy instrumentation was utilized. An infusion line was inserted into one sclerotomy and secured to the globe. A second sclerotomy was made, and a fiberoptic light pipe was immediately inserted to minimize vitreous egress. A third sclerotomy was created, and the vitreous cutter was inserted. To obtain an undiluted vitreous sample, the vitreous was cut mechanically with the vitreous cutter, while the assistant surgeon simultaneously manually aspirated the vitreous. After sufficient undiluted sample was obtained, infusion fluid was allowed to enter the eye and a diluted vitreous sample was obtained in a similar manner. The samples were personally carried to the clinical laboratories by the operating surgeon.~Vitreous fluid analysis was guided by clinical suspicion based on the pre-operative differential diagnosis and the intraoperative posterior segment appearance."