Intraoperative OCT - Real-World User Evaluation in Routine Surgery

In recent years, great progress has been made in intraoperative imaging using optical coherence tomography (iOCT). There are now several commercially available iOCT systems that allow high-resolution imaging of all structures of the eye without interrupting surgery. This real-time visualisation can provide additional information to conventional surgical microscopy, but is relatively expensive. The aim of our study was to find out how often OCT integrated into the surgical microscope is used by trained surgeons, or to what extent they consider that iOCT is relevant for intraoperative procedures.

A prospective monocentric analysis was conducted of the field of application and user-friendliness of the EnFocus Ultra-Deep OCT (Leica Microsystems), a mobile device combination of surgical microscope and OCT. The use and benefit were investigated of iOCT, which was not mandatory. Standardised documentation and evaluation using a questionnaire was performed by the respective surgeon (n = 5) immediately after surgery.

Over a period of 25 working days, 118 procedures were performed in the operating theatre equipped with the microscope-OCT combination. The iOCT was used in 24.6% of the 118 procedures performed. iOCT was regarded as crucial to the intraoperative procedure in 3 of the 29 patients. In one patient, it was possible to check graft orientation during a DMEK operation in a very opaque cornea and, in the second patient, to visualise the correct positioning of an iris diaphragm in the capsular bag. In the third patient, the risk of developing a pseudoforamen was assessed, and this led to the decision not to perform a full gliosis peel.

Experienced surgeons in a university eye hospital with a full surgical spectrum considered that intraoperative OCT was decisive for the course of surgery in only a few selected surgical situations, e.g. in case of limited corneal transparency. The impact of the use of iOCT on post-operative outcome quality still needs to be evaluated by larger prospective studies. On the basis of this survey, the cost-benefit ratio is still unclear.