Intravitreal tissue plasminogen activator to treat refractory diabetic macular edema by induction of posterior vitreous detachment.

OBJECTIVE

To evaluate the effects of intravitreal injection of recombinant tissue plasminogen activator (TPA) for the treatment of refractory diabetic macular edema.

METHODS

A total of 27 patients with refractory diabetic macular edema with no evidence of posterior vitreous detachment were randomly assigned into follow-up (F/U) or TPA treatment groups. To control for the effects of intravitreal injection, an additional 14 patients with diabetic macular edema who were candidates for first-time intravitreal bevacizumab injection were enrolled as the IVB group. For the TPA and IVB groups, 25 μg of TPA or 1.25 mg of bevacizumab, respectively, were intravitreally injected. Fundoscopy, optical coherence tomography, and B-scan ultrasonography were performed at 1 week, 1 month, and 3 months after initiation of the study.

RESULTS

The incidence of posterior vitreous detachment in fundoscopy over the follow-up period was 69.2% in the TPA group, which was significantly higher than that of the F/U and IVB groups (P = 0.001). Best-corrected visual acuity and changes in macular thickness did not significantly differ between the TPA and F/U groups over the 3-month period.

CONCLUSIONS

Intravitreal TPA injection induces posterior vitreous detachment in patients with diabetic macular edema refractory to standard treatment but has no effect on macular thickness or best-corrected visual acuity within 3 months.