Abstract
Purpose::
To evaluate visual acuity and visual rehabilitation after implantation of a telescope prosthesis in patients with bilateral untreatable, end-stage AMD.
Methods::
217 patients aged 55 and older with bilateral disciform (no active CNV) or atrophic AMD and best spectacle-corrected visual acuity (BSCVA) 20/80 to 20/800 were enrolled in this prospective, multi-center trial. Patients were required to demonstrate a 5 letter minimum improvement in BSCVA on the ETDRS chart with an external telescope. 206 patients were successfully implanted with the telescope prosthesis (IMTTM by Dr. Isaac Lipshitz, VisionCare, Saratoga, CA). Patients were treated and managed by a multi-disciplinary team that included a retina specialist, anterior segment surgeon, and low vision practitioner. Per study protocol, 6 visual rehabilitation sessions were conducted during the first 3 months after surgery. Outcome measures included change in BSCVA, NEI VFQ-25, and Activities of Daily Life (ADL) scores. Fellow eyes served as controls.
Results::
Mean baseline BSCVA was 20/316 at distance and 20/250 at near. At two years, distance and near BSCVA improved 3.15 and 2.9 lines from baseline in implanted eyes compared to 0.5 and 1.7 lines, respectively, in fellow eye controls (p<.0001). NEI VFQ-25 scores improved significantly from baseline (p<.01) on 7 of 8 relevant subscales at one-year. Statistically significant improvements were also observed in all ADL subscales. 8/206 (3.9%) telescope prostheses were explanted due to device failure (2), corneal decompensation (2), and patient dissatisfaction (4). Patient education was important when near activity low vision aids were required in conjunction with the telescope-implanted eye (patients require reduced magnification and use more optimal working distance); to optimize ability to alternate eye viewing for central and peripheral visual tasks; to understand depth perception cues; and locate optimal eccentric viewing position if necessary.
Conclusions::
Long-term results demonstrate this telescope prosthesis is effective in improving both visual acuity and quality of life in patients with end-stage AMD. The device works synergistically with existing visual rehabilitation practices; however, pre-operative expectation management and post-operative visual rehabilitation are important to assure successful outcomes with the prosthetic telescope.
Keywords: age-related macular degeneration • low vision