Smartphone Augmented En-Face Guided Epiretinal Membrane Peeling: A 3D Ngenuity Tool For Customized Treatment.

Abstract

Purpose: We aimed to introduce a novel visualization technique of en-face scans during epiretinal membrane (ERM) peeling, by using the in-built picture-in-picture (PIP) modality of the Alcon Ngenuity 3D System, connected to a smartphone.

Methods: Prospective mono-centric interventional analysis on 20 patients undergoing vitrectomy and peeling for idiopathic ERMs. RTVue XR Avanti device was used perform a 6 × 6 mm optical coherence tomography angiography (OCTA). En-face image from a custom slab from 9 μm upon the internal limiting membrane (ILM) to 30 μm below the ILM was taken and 180° flipped. The smartphone was connected to the Alcon 3D Ngenuity display using an HDMI-to-USB cable and the picture-in-picture modality of the display was chosen in the software menu. ERM peeling was performed without dye stain starting from black linear structures on the en-face, indicating area of weaker adhesion to the ERM and could be used as cleavage point for membrane removal using vitreal forceps.

Results: We reported successful peeling initiation and flap lift at the first forceps' grasp in all cases (100%). After ERM peeling, dual blue staining highlighted ILM remnants in 15 cases (75%) and peeling was completed. Total surgical time, including cable connections and projection to the display, was 41.6±9.2 minutes. Intraoperative total peeling time was 11.1±2.6 minutes. Central macular thickness significantly reduced 1 month after surgery (p=0.01).

Conclusion: In summary, this is a cheap and easily reproducible surgical technique to optimize ERM management, offering an intraoperative guide for peeling initiation and minimizing un-necessary surgical maneuvers.