http://www.evrs.eu/medias/2006/congress/Two-year-Phase-II-III-Results-(IMT002)-of-a-Visual-Prosthesis-for-Treatment-of-Central-Vision-Loss-Due-to-End-stage-Macular-Degeneration.swf

Henry L. Hudson, MD, FACS (Tucson, AZ)*

PURPOSE:

To evaluate the safety and efficacy of an implantable telescope in patients with bilateral visual impairment due to end-stage age-related macular degeneration (AMD). The device is designed to improve visual acuity by reducing scotoma size relative to objects in the central visual field.

METHODS:

Eligible patients in this prospective, multicenter trial were =?55 years of age with bilateral moderate to profound visual impairment (20/80-20/800) due to untreatable AMD (geographic atrophy or disciform scar). Exclusion criteria included evidence or treatment of active CNV in the preceding 6 months, diabetic retinopathy, history of retinal detachment, previous intraocular or corneal surgery, and endothelial cell density <1600 cells/mm. 206 patients were implanted with the visual prosthesis (IMTTM by Dr. Isaac Lipshitz) monocularly and participated in postoperative rehabilitation. Visual acuity (ETDRS) change from baseline in implanted eyes was compared to fellow eye controls.

RESULTS:

Mean age was 76 years. Baseline mean distance and near best-corrected visual acuity (BCVA) were 20/312 and 20/250, respectively. At 2 years, mean distance BCVA improved 3.2 lines and mean near BCVA improved 2.9 lines. Gain of =?3 lines of distance BCVA occurred in 59.2% (103/173) of implanted eyes, versus 10.3% (18/174) of fellow eye controls (p<.0001). Overall, 98.2% (170/173) of implanted eyes had improved or stable (no change) distance BCVA. BCVA change was not related to lesion type. NEI VFQ scores, tested to 1 year after implantation, a secondary outcome measure, showed relevant VFQ subscales improved 7 to 14 points. Loss of =?3 lines of distance BCVA occurred in 0.6% (1/173) of implanted eyes, versus 7.5% (13/174) of fellow eyes (p ?=.0013). Mean corneal endothelial cell loss was 20.0% at 3 months, 25.3% at 12 months, and loss from 12 to 24 months was an additional 2.5%. There were 2 cases of corneal decompensation, 1 case of CNV recurrence, and no cases of retinal detachment.

CONCLUSION:

Long-term data demonstrate the implantable telescope is effective in improving visual acuity in patients with end-stage AMD. The device is well tolerated with few reported retinal complications. The study is the first to show quality of life and sustained long-term visual acuity improvements in this severely visually impaired population for which no surgical or pharmaceutical therapies exist.
* Financial interest disclosed