Abstract
Purpose: :
To report on clinical applications of a new combination of an intra-operative spectral domain optical coherence tomography (SD-OCT) connected with the surgical microscope to provide sterile intraoperative OCT evaluation.
Methods: :
Using a Carl Zeiss MeditecTM Cirrus HD-OCTTM which is adapted to the optical pathway of a Zeiss OPMI VISU 200TM surgical microscope, 512x128 macular cube scans were performed at various steps of vitreo retinal surgery and cataract surgery. The acquired volume data was post processed and visualized using a ray-traced three dimensional display system created in the C++ based object oriented programming language COFFEE (Maxon Inc.TM).
Results: :
139 512x128 macular cube scans of 88 patients (88 eyes) were acquired. The surgical procedures included 48 pars plana vitrectomies, with a simultaneously performed cataract surgery and implantation of a posterior chamber lens in 38 eyes. Indication for vitreoretinal surgery was preretinal membrane formation, macular hole, proliferative diabetic retinopathy, silicone oil removal, and primary rhegmatogenous retinal detachment repair. Another 40 eyes had cataract surgery only. It was possible to acquire intraretinal scans with sufficient quality from all patients (pre-, intra -and postsurgically). Decisions for additional membrane peeling if incomplete, knowledge about the behavior of the macular hole immediately after ILM removal, information about maintenance of the foveal depression during membrane peeling, and detection of a clinically invisible fluid accumulation under silicone in a supine position or a clinically diagnosed "macula on" retinal detachment and the behavior of the fovea immediately after cataract removal could be gained by using the intraoperative OCT.
Conclusions: :
Intra-surgical SD-OCT evaluation offers additional information to the surgeon about vitreoretinal behavior. OCT examinations of high quality can be performed during surgery without loss of time and sterility. Immediate post processing in 3-D is possible.
Keywords: vitreoretinal surgery • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • cataract