Intraoperative Optical Coherence Tomography For Ab Externo Preserflo Microshunt Glaucoma Surgery

The purpose of this study was to introduce an innovative surgical technique for facilitating insertion and precise positioning of the PreserFlo MicroShunt (PMS) by means of intraoperative optical coherence tomography (iOCT)

Ophthalmolgy deprtment, Shaare Zedek Medical Center, Jerusalem, Israel 

A retrospective review of videos and photos of the novel surgical tecnique utilizing intraoperative optical coherence tomography (iOCT) for insertion and precise positioning of the PreserFlo MicroShunt (PMS).

The application of iOCT proved valuable prior to, during, and after the PMS implantation. Before implantation, iOCT enabled real-time insights into AC anatomy, providing details on the iris root insertion and iridocorneal angle position and width. During implantation, iOCT provided direct visualization of key elements, including the transscleral route creation , the point of entry into the AC with regard to the iris and iridocorneal angle, and accurate passage of the PMS through that route. Post-implantation, iOCT confirmed the precise positioning of the PMS within the AC, ensuring its proximity to the iris at a safe distance from the corneal endothelium as well as verifying the correct placement of the external end close to the sclera.

Application of iOCT during PMS implantation represents an advancement in glaucoma surgery, offering unparalleled visualization of critical steps that had previously been obscured. This enables precise monitoring of the formation of the transscleral route, the point of entry into the anterior chamber, the positioning in the AC relative to the iris and cornea, the positioning of the external end relative to the sclera and the final position of the external tip underneath Tenon layer and conjuctiva. Such superior visualization facilitates immediate identification and correction of potential misplacements, thereby enhancing optimal functionality and long-term success of the device.