Drs. David Lally and Jay Duker demonstrate transretinal biopsy of a choroidal tumor using 23-gauge vitrectomy instrumentation. The 32-year-old patient presented with decreased vision. Examination revealed a choroidal lesion, 3.4 mm thick, with a nodule overhanging the optic nerve. A 23-gauge pars plana vitrectomy was performed. After IOP was increased to 60 mmHg, a 27-gauge needle was inserted transretinally into the tumor and its contents aspirated into a syringe. The patient’s vision improved from 20/30 to 20/20 on postop day 1. Lab results were positive for a class 1B mixed cell choroidal melanoma. Due to the tumor’s proximity to the optic nerve, the patient was treated with gamma knife radiotherapy.