LVES - A NEW OPTOELECTRONIC LOW-VISION AI D - FIRST RESULTS

A new low vision aid (LVA) - the Low Vision Enhancement System or LVES , which were as developed at the Johns Hopkins University in Baltimore , is now commercially available. This instrument allows a magnificatio n up to 10 times with control of contrast and luminance while the fiel d of view is very large: 60 x 40 degree. We present first results conc erning LVES in comparison to conventional LVAs. Patients and Methods 6 0 consecutive patients suffering from macular dystrophy, macular degen eration, optic atrophy, tapetoretinal degeneration, or diabetic retino pathy were included in this study. We compared visual acuity with glas ses, with telescope and using LVES. Furthermore we compared contrast a cuity by the use of the Pelli-Robson-charts as well as the subjective impression of the patients. Results Improvement of visual acuity with LVES compared to correction with glasses was 8 log steps on average an d up to 3 steps as compared to the use of telescopes. More important i s the improvement of contrast sensitivity (0-16 steps) and the reduced glare. Despite the subjective improvement of visual acuity and contra st sensitivity the majority of patients could not imagine to use LVES regularly. A significant improvement as compared to conventional low v ision aids is possible for special applications such as office work, r ecognition of faces or images or for looking at a blackboard. Conclusi on In addition to traditional LVAs, the Low Vision Enhancement System opens up possibilities for a very small group of patients. Especially patients suffering from macular dystrophy or Lebers optic atrophy may benefit from this new system. The most important advantage of LVES is the improvement of contrast sensitivity and the significantly decrease d glare sensitivity. Additionally the near working distance is changea ble. The variable magnification allows an easier fitting to various ta sks. Prior to the prescription of LVES a detailed and time consuming t esting is necessary.