By Jule Ann Lieberman, MS CLVT/CATIS and the Vision Loss Resource Team
During the 2020 PCB Conference held virtually this past October, I spoke on how magnification works and how optical and technology options are used for reading with low vision. In this article I wish to primarily discuss magnification devices for distance tasks along with near reading tasks.
In 1982 I visited the William Feinbloom Low Vision Center located in Philadelphia. As part of my comprehensive low vision exam, I was introduced to Bioptic Glasses. Wikipedia describes Bioptics as follows: “Vision-enhancing lenses that magnify between two and six times and are used to improve distance vision for those with severely impaired eyesight.” Think of a pair of glasses with one or two telescopes mounted strategically in the lens portion of prescription spectacles. A Low Vision Specialist would evaluate the potential use for the patient including the optimal placement of the telescopes in what is termed the carrier lens. All prescription glasses include a measurement of the pupillary distance, the point where your eyes position to use both eyes at the same time.
Placement of the telescopes relies on this measurement for best results. The magnification level will dictate the length of the telescope, with higher magnification needs requiring longer telescopes. To understand this concept, think of the size of the telescopes to magnify the night sky; the larger the telescope, the closer the stars will appear. With telescopes for low vision, larger telescopes bring objects closer to you to make the object appear larger and more visible. My first experience with Bioptics included a trip outside the low vision center where I was able to spot and read successfully a street sign from the middle of a city-long block. My acuity with standard corrective lenses at the time was 20/350 and the Bioptics increased my acuity to approximately 20/35 for distance acuity. To explain this acuity measurement, 20/200 is the top line of the eye chart and 20/20 the bottom smallest line on the eye chart representing typical vision. I was also prescribed a “reading cap” that was placed on the end of one telescope, which provided magnification in a small field for reading. Over the years, Bioptics improved with lighter and shorter telescopes with increased magnification and smaller telescopes placed on the interior portion of the lenses for more cosmetic appearance. In recent years, an auto focus feature which uses a re-chargeable battery lasting eight hours of continuous use was added. The auto-focus Bioptics will adjust quickly for multiple activities, reading street signs, watching television, and reading. Bioptics are a great option for a person who has been diagnosed with macular degeneration, Stargardt’s Dystrophy and Albinism who has best correction of 20/300 or better, using typical corrective glasses. In 1982 Pennsylvania had no laws allowing use of Bioptics for driving. Currently, my Bioptics are no longer effective for me; however, I remember the thrill of seeing the street signs and watching baseball games both on TV and in person.
In as many as 28 states, Bioptics can be used while operating a motor vehicle. In November 2020, the Pennsylvania Legislature passed, and Governor Wolf signed into law Act 131, which addressed several items regarding driving. One section of this act included allowing persons using Bioptics to apply for driver permits and licenses in the Commonwealth of Pennsylvania. According to the PennDOT (Pennsylvania Department of Transportation) website: “PennDOT is currently developing the program’s training and licensure process and will implement the program on the effective date of this section of the legislation, which is September 27, 2021.” For updates to this development, visit www.penndot.gov/news or contact the Department of Motor Vehicles Driver and Vehicle Services Customer Call Center staff at 717-412-5300.
Bioptic driving requires a prescription by a low vision specialist and training by a driving instructor who understands the proper use. Additional requirements may include a restricted license limiting hours of driving and limits on what roads can be traveled. A driver using Bioptics will spend 95% of the time looking through the carrier lens where the standard prescription correction is located and will tilt head and look into the telescopes to spot road signs and objects ahead. This requires training and practice for ultimate safety.
A friend of PCB who lives in Virginia has been driving with Bioptics for two years to date. She was introduced to this idea after hearing from another in Virginia who was successfully driving using Bioptics for a few years. She did not want to “lose the freedom of driving” and discussed with her eye doctor this potential. After receiving some training from the eye doctor’s office for using Bioptics to watch television, walk outside, ride a bicycle, ride in a car while wearing Bioptics for at least three months, and after successful testing, she was advised to pursue this option for driving. This led to contacting the Department of Motor Vehicles where she scheduled a driving test with a DMV instructor along for the ride. She currently has only driven in Virginia and has not indicated any restrictions to where and when she may drive. Her eye doctor states if she feels comfortable, she is permitted to drive at night.
New trends in wearable low vision technology are devices that simulate the functions of a video magnification system. Based on virtual reality glasses, devices such as those from IrisVision, eSight, NewEyes, and a few others have options for both distance and reading magnification built into a goggle type of wearable. These devices must be used while still and cannot be used while walking or operating a motor vehicle. As with many video magnification systems, contrast, color options, and zoom magnification are standard features. Optical Character Recognition is also possible with speech reading of documents, and text can be displayed in larger size while reading aloud takes place. Many of these wearable video magnification systems also connect to the Internet through Wi-Fi network access where newspaper subscriptions can be accessed. The best candidates for these devices are persons who have acuity of 20/400 or better when wearing corrective lenses, benefit from high contrast and color display options, and have interest in connecting to the Internet for reading. The devices have auto focus and can easily change from near reading to viewing at a distance. Activities such as watching television, movies, and sporting events can be viewed using the zoom magnification feature. During an Assistive Technology Day at TechOWL in November 2019, several visitors tried out these devices. The most common comments were that each of the devices we had to try would need some training to use most effectively and were somewhat heavy to wear for extended periods. TechOWL has in the equipment lending library both IrisVision and NewEyes to borrow for short term evaluation. Visit the TechOWL website www.techowlpa.org to sign up as a library user or call 800-204-7428 for additional assistance in borrowing all low vision device options available in the equipment inventory.
Check with your nearest low vision specialist to determine if either a Bioptic or wearable video magnification device is right for you. Contact the PCB Office to locate low vision and rehabilitation centers nearest to you.