Intravitreal recombinant tPA before vitrectomy for diabetic tractional retinal detachment: A randomized controlled trial.

PURPOSE: To investigate the effect of intravitreal recombinant tissue plasminogen activator (rt-PA) injection before vitrectomy on surgical facility and outcome in diabetic tractional retinal detachments (TRD). METHODS: Prospective, randomized, interventional clinical trial. A total of 38 eyes with diabetic TRD were candidates for vitrectomy. Patients were randomized 1:1 to receive intravitreal rt-PA, five to seven days before vitrectomy or no injection. Intraoperative surgical facility and anatomic success at month 3 after surgery were assessed. RESULTS: Mean patient age was 54.2 ± 9.4 years. There was no statistically significant difference between rt-PA and no injection groups with regard to anatomic success (89% versus 95%, respectively, P = 0.547) and best corrected visual acuity at 3 months (2.0 versus 2.1 logMAR, respectively, P = 0.840). However, surgical facility score was statistically significantly lower in rt-PA injection group compared to no injection group (4.1 ± 1.7, 5.8 ± 2.0, respectively, P = 0.007). CONCLUSIONS: Vitrectomy for TRD was easier after preoperative rt-PA injection, without affecting the anatomic and visual outcomes.

The effect of intravitreal recombinant tissue plasminogen activator injection on diabetic tractional fibrovascular membranes: Proposed criteria using optical coherence tomography.

PURPOSE: To evaluate the effect of intravitreal recombinant tissue plasminogen activator (tPA) on diabetic tractional fibrovascular membranes (FVM) using proposed optical coherence tomography (OCT) criteria. METHODS: This prospective, interventional case series enrolled eyes with tractional retinal detachment who were candidates for pars plana vitrectomy. OCT images were obtained to evaluate the border of the attached-detached retina and overlying FVP at baseline and 1 week post-intravitreal tPA injection using the follow-up scan acquisition protocol. Two independent graders assessed retinal detachment (RD) height, FVM height, and retinal thickness at the site of membrane attachment. RESULTS: Thirteen eyes from 13 individuals were included. Assessment of RD height, FVM height, and retinal thickness at membrane attachment point were feasible at both visits in 10/13 (77%), 10/13 (77%), and 8/13 (62%) of eyes, respectively. There was excellent agreement between the two graders for all measurements (all ICC > 0.94). Release of the retina-membrane attachment point was not observed in any eyes. No statistically significant change was found in any of the measured parameters. CONCLUSIONS: Excellent agreement was achieved between the graders for quantitative assessment of diabetic FVM using our proposed OCT criteria. We did not observe a significant change in the FVM measurements, 1-week after intravitreal tPA injection.

Spatial distribution of diabetic capillary non-perfusion.

OBJECTIVE: To evaluate the distribution of capillary non-perfusion (CNP) in superficial and deep capillary plexuses (SCP and DCP) in eyes with diabetic retinopathy (DR). METHODS: In this retrospective case series, macular optical coherence tomography angiography (OCTA) images were obtained from eyes with DR without diabetic macular edema (DME). The area of CNP in SCP and DCP was delineated using an automated approach after excluding the foveal avascular zone (FAZ) and major retinal vessels. The distribution and spatial correlation of the CNP in each layer were analyzed. RESULTS: Forty-three eyes of 27 patients with DR with a mean age of 59.10 ± 9.05 years were included. The mean CNP area in SCP was statistically significantly higher than DCP (0.722 ± 0.437 mm2 vs. 0.184 ± 0.145 mm2 , respectively, p < .001). There was a statistically significant association between mean BCVA (0.28 ± 0.21 logMAR) and CNP area in DCP (p = .01). After automated subtraction of CNP areas in DCP from SCP, 25.43 ± 15.05% of CNP areas in the DCP had co-localized CNP areas in SCP. The CNP percentage was statistically significantly different between the concentric rings on foveal center, both in SCP and in DCP (both p < .001) showing a decreasing trend from the outer ring toward the center. CONCLUSION: In DR, SCP is more ischemic than DCP. This is in contrast to the previously described oxygenation-dependent ischemic cascade following acute retinal vascular occlusions. This study provides further insight into the retinal ischemia in DR.