Abstract
Purpose :
To quantify changes in retinal thickness after subretinal injection of tissue plasminogen activator (tPA) for displacement of large submacular hemorrhages (SMH) in a retrospective, clinical study.
Methods :
Spectral-domain optical coherence tomography (SD-OCT) from six eyes of six patients were analyzed before and after pars plana vitrectomy and injection of subretinal tPA for displacement. Thickness measurements for the inner and outer retina were made using the caliper feature of the Spectralis device in concentric regions of the macula involving the SMH as well as normal areas immediately adjacent to the SMH both before and after the subretinal tPA. The inner retina was measured from the internal limiting membrane to the edge of the inner nuclear layer (Figure 1A), while the outer layer was measured from the outer plexiform layer to the external limiting membrane (Figure 1B). Measurements of uninvolved retina were made in symmetrically located areas corresponding to the location of the detached pathologic measurements. A two-tailed paired t-test was used to determine significant differences in BCVA (logMAR). A one-way ANOVA and post-hoc comparisons were used for the comparison of retinal thicknesses (μm) in different areas. Statistical significance was determined by a p-value of < 0.05.
Results :
BCVA was significantly improved after surgery (2.00±0.65 vs 0.92±0.36; p=0.015). There was no significant change in the inner retinal thickness from before to after surgery in the retina overlying the SMH (234±54 μm vs 178±27 μm; p=0.25) (Figure 1A). A significant decrease in outer retinal thickness was noted after surgery in the area overlying the SMH (178±77 μm vs 73±38 μm; p=0.003) (Figure 1B). No changes in retinal thickness were observed in regions immediately adjacent to the SMH as a result of subretinal tPA injection for either the inner (145±19 μm vs 149±37 μm; p=0.69) or outer (87±5 μm vs 82±8 μm; p=0.28) retina.
Conclusions :
Subretinal injection of tPA and induction of macular detachment for displacement of SMH can improve vision and restore retinal anatomy. Subretinal tPA injection and bleb formation does not adversely impact retinal thickness in uninvolved regions of the macula that are detached as a consequence of bleb formation. The subretinal tPA displacement appears capable of restoring retinal thickness to near normal levels as measured by SD-OCT.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.