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CHICAGO -- A simple-to-use portable artificial vision device (OrCam My Eye) may improve functionality and independence in patients with low vision.

Performance on tests related to function and independence, including recognizing money, reading e-mails on an electronic device and reading a menu, improved shortly after use of the low vision aid, said Elad Moisseiev, MD, at the 2016 .

The World Health Organization estimates worldwide prevalence of low vision to be 246 million. Self-reported quality of life is compromised in patients with low vision.

"Although we have been witnessing a lot of technological and medical advances in recent decades, the field of low vision has been particularly lagging behind," with low vision devices being cumbersome and not allowing ambulation, said Moisseiev, from Tel Aviv Medical Center, Israel.

With advances in technology, portable electronic low vision devices are gaining interest. The OrCam device is a commercially available optical character recognition device that is capable of recognizing print, monetary denominations faces and other objects taught to it.

It is programmed to recognize faces and products, and is designed to be compatible with natural light. The device consists of a miniature camera and a bone conduction earpiece that clip to the frame of glasses. "It is very lightweight, doesn't have a battery in it, it doesn't tip the glasses or change the way the user looks," he said. It is activated by the user pointing, pressing a trigger button or tapping the device.

In the prospective pilot study, 12 visually impaired patients 18 years and older with best corrected visual acuity of 20/200 or worse in their better eye, qualifying as legally blind, completed a 10-item test that simulates activities of daily living. The test was devised by the investigators for the purpose of this study and has not been validated. It was conducted at patients' first visit and again after use of the OrCam at home for 1 week. Patients with documented cognitive impairment and hearing loss were excluded from participating. The 10 tasks on the test were:

• Reading an e-mail message displayed on an electronic device
• Recognizing money
• Reading a newspaper article
• Finding a specific headline in a newspaper
• Reading a menu
• Differentiating between products of a similar size
• Reading a single-spaced letter
• Reading aloud from a page in a book
• Reading signs on the wall
• Reading a stop sign from 8 feet away

A score of "1" was given for each task completed and a score of "0" if not completed, and a total score of 0 to 10 was calculated. Patients completed the test using their BCVA, other low vision aids that they used regularly and the OrCam. No patient could perform five of the tasks using BCVA, 11 (92%) could recognize bill denominations, eight (67%) could locate a specific room in a hallway by using wall-mounted signs and seven (58%) were able to recognize products and differentiate between cereal boxes of a similar size.

Test scores improved from a mean of 2.5 using BCVA to 9.5 using the OrCam at the first visit (P<0.001), with further improvement to 9.8 after 1 week of use (P<0.001). A subset of seven patients also used other low vision aids; among these patients, test scores improved from 6.0 to 9.7 (P=0.014) with use of OrCam.

Patients completed a five-item satisfaction questionnaire after using the portable device, answering each item on a scale of 1 (strongly disagree) to 5 (strongly agree). "They all reported it was easy to use; only one of them called us in the middle of the week with technical issues," said Moisseiev. Mean scores on the questionnaire items were 3.9 for simple to understand, 4.1 for easy to use and 3.9 for utility in daily life. They also indicated that they would recommend it to other patients with low vision (mean score 3.9).

"There is nothing quite like this out there. We've proved that the OrCam is effective and gives these people increased functionality, which is very important for people missing out on a big part of their lives."

Moisseiev conducted the study while at the University of California, Davis, Sacramento.