Feasibility of Intrasurgical Assessment of Submacular tPA injection for Submacular Hemorrhage Utilizing Intraoperative OCT

Abstract

 

Purpose

 

Pars plana vitrectomy (PPV) with subretinal hemorrhage displacement is a viable treatment option for patients with subretinal hemorrhage from choroidal neovascularization. The architectural changes that occur at the level of the retina during subretinal tissue plasminogen activator (tPA) injection and associated alterations to the hemorrhage remain unknown. This study was performed to determine if intraoperative OCT (iOCT) can assess alterations that occur in the retina following subretinal injection of tPA.

 

Methods

 

Eyes that underwent vitrectomy and subretinal injection of tPA were identified from the PIONEER study, a prospective clinical study assessing the feasibility and utility of iOCT in ophthalmic surgery. A microscope mounted spectral domain OCT system (Bioptigen SDOIS) was utilized for iOCT imaging, and a standardized scan and image acquisition protocol was followed. Images were obtained at surgeon-specified procedural milestones (e.g., preincision, post-tPA injection). iOCT images were reviewed for architectural alterations following tPA injection.

 

Results

 

Three eyes of 3 patients were identified for analysis. Mean age was 83 years. All patients had an underlying diagnosis of neovascular age-related macular degeneration. iOCT was successfully obtained in 100% of eyes following subretinal tPA injection. In all cases, increased subretinal fluid was noted with differential reflectivity visualized between the hemorrhage/tPA interface confirming appropriate localization of tPA injection. iOCT image assessment revealed probable needle tracks in multiple scans in 2/3 patients. No iOCT-related or intrasurgical complications were noted.

 

Conclusions

 

iOCT can successfully be performed during PPV with subretinal tPA injection. Utilizing iOCT, appropriate placement of tPA solution was visualized in the subretinal space. Architectural changes, such as needle tracks, are also visualized. Future areas of research include the use of microscope integrated OCT systems to visualize the real-time needle placement for subretinal fluid injection and functional correlates to visualized anatomic alterations.

 

 

Pre-incision and post tPA injection iOCT scans. Hemorrhage/tPA interface is indicated by the arrow. Note variable subretinal hyporeflectivity following injection.

 

 

Post tPA injection iOCT scan. Note prominent subretinal fluid. Arrows indicate possible needle track.

 

Keywords: 412 age-related macular degeneration • 762 vitreoretinal surgery • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)