WHAT IS LOW VISION?
Low Vision is a bilateral impairment to vision that significantly impairs the functioning of the patient and cannot be adequately corrected with medical, surgical, therapy, conventional eyewear or contact lenses. It is often a loss of sharpness or acuity but may present as a loss of field of vision, light sensitivity, distorted vision or loss of contrast. Low vision often may occur as a result of birth defects, injury, the aging process or as a complication of disease.
Low Vision services do not cure the cause of the vision problem but rather utilize the remaining vision to its fullest potential. Low vision care does not replace the need for other concurrent treatments such as laser, medication and surgery. Low vision doctors prescribe prescription eyewear, filters, microscopic – telescopic eyewear, magnifiers, adaptive equipment, closed circuit television systems, independent living aids, training and counsel patients.
WHAT IS A LOW VISION SPECIALIST?
Low Vision Specialists are licensed Doctors of Optometry or Ophthalmology, who are skilled in the examination, treatment and management of patients with visual impairments not fully treatable by medical, surgical or convention eyewear or contact lenses. They are licensed to examine, diagnose and treat various ocular conditions.
Low Vision Rehabilitation is a team effort often involving the low vision specialist (an optometrist orophthalmologist), rehabilitation teachers, mobility / orientation specialists, occupational therapists, technicians, and other professions as needed.
WHAT HAPPENS DURING A LOW VISION EXAM?
The Low Vision Examination begins with a complete history. Special emphasis is placed on the functional problems of the patient including such items as vision to read, functioning in the kitchen, glare problems, travel vision, the workplace, television viewing, school requirements, etc. It will also include a careful review of your ocular and medical history.
Preliminary test may include assessment of ocular functions such as depth perception, color vision, contrast sensitivity, curvature of the front of the eye. Careful measurements will be made of the visual acuity using low vision test charts followed by low vision refraction. Low vision test charts include a larger range of letters to more accurately determine a starting point for measurement of low vision. A low vision refraction determines the measurement of the patient’s prescription by special techniques which may include changing the lighting levels, testing through filters and using larger changes which may be easier for you to view.
If the patient has decreased acuity, the doctor may test with various telescopic systems which magnify distance vision. These may be spectacle mounted or handheld. He may also assess your response to filters to control glare. Various reading aids including strong reading eyewear, magnifiers, electronic magnifiers and even electronic reading machines may be tested.
Visual fields are usually evaluated and if the patient has a reduced visual fields, field enhancing devices may be evaluated and simple therapies to improve the patient’s use of their residual field may be prescribed.
Eye health testing will include a biomicroscopic examination of the external eye structures and a dilated internal examination of the retina. Glaucoma tests are performed.
The doctors at Angeles Vision Clinic will counsel you on how your condition will effect your vision and what you may do to enhance and protect your vision. Independent living aids may be reviewed to fit specific patient problems.
When conventional spectacles can no longer help and surgery or medical treatment is not appropriate, or very prolonged, then it is time to consider low vision aids. These come in a bewildering array of strengths and designs. They range from simple hand-held lenses to electronic devices. Different ones are needed for different visual tasks. Please visit our Low Vision Aids page.