Vitreomacular traction syndrome: a comparison of treatment with intravitreal plasmin enzyme vs spontaneous vitreous separation without treatment.

PURPOSE: To evaluate the effects of intravitreal autologous plasmin enzyme (APE) in patients with focal vitreomacular traction (VMT).

METHODS: APE was obtained by incubation of patient-derived purified plasminogen with streptokinase, and intravitreally injected 5-12 days later. Twenty-four hours after injection, in case of incomplete VMT release, a pars plana vitrectomy was performed. The hyaloid internal limiting membrane adherence and removal of the posterior hyaloid were intraoperatively evaluated.

RESULTS: Thirteen patients were recruited. During preparation of APE, five patients had spontaneous release of VMT. Eight patients received APE injection (2 IU). In five patients, spontaneous resolution of VMT occurred before APE administration. Twenty-four hours after injection, persistence of VMT was detected in all the eight treated patients. Best-corrected visual acuity was 0.51±0.37 LogMAR at baseline, improving to 0.23±0.14 LogMAR at 6 months (P=0.002). Foveal thickness was 464±180 μm at baseline, reducing to 246±59 μm at 6 months (P<0.001). Hyaloid was intraoperatively judged 'partially detached' in seven cases and 'totally detached' in one case. Hyaloid peeling was evaluated 'easy' in six eyes and 'very easy' in two eyes.

CONCLUSIONS: In the current study, there was a large percentage of spontaneous resolution of VMT before an APE administration. A single intravitreal APE injection seems insufficient to induce a complete posterior vitreous detachment in these patients.