Abstract
Purpose::
To examine the ability to determine by OCT the potential recurrence of neovascular AMD and telescope-to-cornea anterior chamber clearance in patients with the Implantable Miniature Telescope (IMTTM by Dr. Isaac Lipshitz, VisionCare, Saratoga, CA). The investigational telescope prosthesis has been developed for patients with end-stage AMD (bilateral disciform scars or geographic atrophy) and previously shown to improve visual acuity, performance in daily activities, and overall vision-related quality of life. The telephoto optical properties of the eye-telescope system and composition of the telescope prosthesis present unique challenges for post-implantation evaluation of the retina. Methods for both retinal and anterior segment imaging can aid clinical evaluation after implantable telescope placement.
Methods::
Evaluation of retinal thickness and telescope-to-cornea clearance were conducted with the Stratus OCTTM retinal and Visante OCTTM anterior segment imaging systems (Carl Zeiss Meditec, Inc., CA), respectively. The telescope prosthesis was implanted in 206 patients age 55 and older with bilateral end-stage AMD. Preop exclusion criteria included evidence or treatment of CNV in the preceding 6 months. OCT evaluation was performed at select centers with OCT capability. 10 patients underwent Stratus OCTTM testing in telescope and unimplanted fellow eyes after telescope implantation. 15 patients underwent postop anterior segment Visante OCTTM imaging. The telescope prosthesis is comprised of glass micro-optics which are housed in a glass cylinder. 2.2X and 3X device models were available in the prospective, multi-center IMT002 clinical trial.
Results::
Good quality images were obtained in all cases. With the Stratus OCTTM, images in the telescope eye appeared smaller and retinal thickness appeared reduced secondary to optical effects. Quantitative determination of this effect can be conducted. Visante OCTTM evaluation was performed without hindrance by optical effects. Mean telescope-to-cornea clearance was 2.63mm (SD ± 0.48mm).
Conclusions::
Although patients with end-stage AMD present with non-functioning maculas, detection of CNV recurrence in telescope implanted eyes will help retinal specialists treat neovascularization to minimize potential visual acuity loss. Technical aspects of retinal OCT imaging and evaluation will be discussed. Additionally, anterior segment OCT is useful to ascertain postop clearance from the telescope to the corneal endothelium.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: systems/equipment/techniques • retina