Lighthouse International's staff of industry leading experts occasionally answer select questions about eye disorders, low vision treatment and prevention, assistive technology, and more! Submit your vision-related questions today!
Meet Our Experts
Recent Ask the Expert Questions
Q: I have been suffering from low vision and dryness of the optic nerve for the last 24 years. My doctor said there is no treatment available. Is there anything I can do?
A: Depending on what type of optic nerve disease you have, there may be treatment available. It would be difficult for me to outline the treatments available for your optic nerve disease without knowing the specific type of condition you have. Optic nerve disease encompasses a broad range of conditions.
You may also suffer from dry eyes, which is an ocular surface condition, unrelated to the optic nerve condition. Dryness of the eyes is alleviated by using lubricating eye drops that can be purchased over the counter at any drugstore.
Because of the damage to the optic nerve, you are most likely experiencing “low sight” due to reduced contrast sensitivity associated with optic nerve diseases. Therefore, you notice reduced vision in many lighting conditions including daylight which requires that you wear tinted filters indoors and outdoors to protect your eyes from glare problems that you may be experiencing.
It is recommended that you have a dilated eye examination by an optometrist or ophthalmologist in order to determine which optic nerve disease you have and determine which treatment is most appropriate for your condition. – Linda Pang, O.D. at Lighthouse International
Q: Are there any new techniques for assisting patients with hemianopia or loss of peripheral vision other than scanning?
A: I assume that by "scanning" you mean turning the head or eyes laterally to pick up clues from the missing left side of the visual field. There are several variations of prisms that can enhance your field of vision.
There are 3 approaches:
- The standard practice is to introduce a base left full prism of about 12 diopters facing base left for both eyes which shifts the visual field to the right. This means that a portion of the missing left field is brought into the right field area.
- A variation of this is a prism that occupies only the left half of the eyeglass which allows a person to look into that prism and experience a shift of invisible left field into the visible field.
- The third method is an invention by Dr. Eli Peli, a research optometrist in Boston. The innovation is also a prism but set in a different way. Two small rectangular prisms are set on a lens in a frame above and below the horizontal axis. The person shifts his or her gaze up or down into these small prisms and experiences the missing field that "jumps" into the prism. These are difficult to get used to, but Dr. Peli claims in his research paper that over 40% of patients persist using them.
Q: I am a 53-year-old male who needs glasses for reading. But a few hours after reading or doing close up work wearing my glasses, I get very painful headaches. Do you know what could be causing this? My reading glasses are 1.5 magnification.
A: It is not clear whether your +1.50 prescription is an over-the-counter (OTC) prescription or that you received a full evaluation as well as a prescription from an optometrist or ophthalmologist. There are many problems associated with OTC prescriptions. They do not correct for unequal prescriptions (unequal refractive error), astigmatism or properly position the pupils of each eye in the lenses. They do not often correct for lens aberrations as well. I would consult with an eye doctor to make sure that you have the appropriate reading, distance, as well as intermediate correction for the computer. - Dr. Bruce Rosenthal, Chief of the Low Vision Programs, Lighthouse International
Ask the Expert Archive
Browse our Ask the Expert Archive to view previous questions and answers.