The NG telescope is a modification of the FDA-approved Implantable Miniature Telescope (IMT), which is a Galilean telescope available with a magnification size of 2.2× or 2.7×. The IMT is a monovision device and is implanted in the capsular bag of one eye while the other eye serves to provide visual field.
Whereas the IMT has PMMA haptics and a glass optic, the NG device features foldable silicone haptics that allow it to be injected directly into the capsular bag through a smaller incision and using a smaller capsulorhexis.
"The IMT, VisionCare's telescope implant, is an important advance in visual rehabilitation for patients with end-stage macular disease," said Dr. Kleinmann, Department of Ophthalmology, Kaplan Medical Center, Rehovot, Israel. "Results from a series of 206 patients with end-stage age-related macular degeneration with this device implanted show that 60% of them benefited with a gain of 3 or more lines of best-corrected visual acuity and improvement in quality of life. However, there was also a 20% decrease in endothelial cell count in these eyes at 3 months after the operation that is related to the trauma of the surgery."
"The experience from this preclinical study shows the NG version may allow reduced trauma to the corneal endothelium, better control during surgery, and less induced astigmatism," Dr. Kleinmann said.
The preclinical study investigating the surgical feasibility and stability of the NG telescope included eight New Zealand White rabbits that underwent removal of the crystalline lens and randomly received the injectable version of the device in one eye and the commercially available IMT in the fellow eye.
Compared with implantation of the available telescope prosthesis, the NG device surgeries were done through a significantly smaller incision (6.5 versus 9.8 mm) that could be closed with significantly fewer sutures (3.75 versus 6.25). The size of the capsulorhexis needed was also significantly smaller in eyes with the NG telescope implanted compared with the parent model (6 versus 7 mm).
In addition, the operative time for implanting the NG telescope was 23% shorter than the procedure for implanting the original IMT device.
"This latter difference was also statistically significant and achieved even though the surgeon, Danny Sachs, MD, was very experienced with implanting the commercially available IMT and was implanting the NG device for the first time in this study," Dr. Kleinmann said.