Henry Greene: Ocutech has developed a prescribing protocol to help low vision specialists determine if their patient is a promising candidate for Bioptic Telescopes. We divide the protocol into 2 parts: hard signs and soft signs. Hard signs are those that we can measure in the clinic. Soft signs are more of an opinion about the behavior and character of your patient. Hard signs include: visual acuity, dominance and response to contrast. We’d like to have visual acuity between 20/70 and 20/200, though individuals with acuity as poor as 20/400 can respond to telescopic devices. We are hopeful that their dominant eye is also their better seeing eye. A convenient way to identify which the dominant eye is, is to ask the patient to pick up and look through a hand held monocular telescope. Almost reflexively they will take it to the dominant eye. And lastly we want to see how they see through the telescope looking at a low contrast target. Most individuals have no trouble reading high contrast targets with the telescope, but since the world is low contrast, we suggest they look at an individual’s face from across the room through the telescope. We want them to see it better and sharper then they could without it. Some individuals will tell you they see it larger but they don’t see it better. These individuals may need more retinal illumination and more contrast because of the nature of their macular disorder.
Soft signs are more behavioral in nature. There are three questions to ask: Does the patient have appropriate goals for the use of the telescope, which are usually midrange and further. Does the patient show appropriate dexterity with the use of the device? Do they take to it naturally and are enjoying using it? And lastly, are they enthusiastic, do they have a motivation to improve their ability to see at a distance, to see signs, to watch TV, to see faces and make eye contact and stay connected? If all those things are positive then you have a very favorable prognosis for a Bioptic Telescope.