Implantable telescope may be option for bilateral, endstage AMD

May 1, 2005

An implantable miniature telescope (IMT, VisionCare Ophthalmic Tech- nologies, Saratoga, CA) may offer improved visual acuity and quality of life in patients with bilateral, endstage age-related macular degeneration (AMD), according to Paul R. Lichter, MD, who made a presentation on behalf of the investigators.

The IMT appears to be fairly safe with no reports of retinal complications or corneal decompensation, although mean endothelial cell loss slightly exceeded the goal of 17% at 6-month follow-up. As far as efficacy was concerned, more than 90% of patients evaluated in the study had a greater than or equal to 2-line improvement in best-corrected visual acuity (BCVA) at the 6-month time point. Dr. Lichter reported on these phase II/III trial results of the device during the American Academy of Ophthalmology annual meeting.

"Patients have to be realistic and understand that this is not a cure," Dr. Lichter said. "Optimal outcome requires a fairly intense visual rehabilitation commitment to achieve these functional goals. Not all patients who would be eligible from a vision standpoint should be eligible from the selection standpoint."

Patients underwent six visual rehabilitation sessions during the 3-month postoperative period to help them adjust to the IMT for daily activities, he said.

Of the 218 patients enrolled in the prospective, multicenter study, 206 patients had a successful implantation. Eleven patients did not receive the IMT because of capsular tears during the cataract extraction in eight cases, two cases of suprachoroidal hemorrhage, and one case of suspected suprachoroidal hemorrhage. Two patients had the device removed, he reported.

Postoperative complications Postoperative complications included elevated IOP and choroidal edema during the first month after implantation. Other adverse events were a distorted pupil and a mean endothelial cell loss of 22% at 6 months, which exceeded the predetermined goal of 17%. The mean endothelial cell count dropped from a baseline of 2,490 to 1,940 cells per mm2, Dr. Lichter said.

However, there were no retinal complications or corneal decompensation in patients at the 6-month follow-up. Patients will continue to be followed every 6 months, he noted.

Patients were eligible for the implant device if they had bilateral, stable, untreatable AMD, geographic atrophy, or Stargardt's disease. They had to have a cataract in the study eye and their baseline BCVA had to be between 20/80 and 20/800.

Patients could not have active choroidal neovascularization (CNV) or have had treatment for CNV in the last 6 months. Others were excluded if they had intraocular or corneal surgery, he said.