Patient Care

Potential Acuity Meter Test (PAM)

These work on different principles, but both are helpful in assessing retinal function.  The PAM projects an eye chart directly on the retina and bypasses the cataract.  This allows the examiner to test the visual acuity without interference from the cloudy lens.  For the Super Pinhole, the patient looks at a special chart through a disc with tiny holes.  This allows the patient to isolate tiny clear spots in the cataract. 

When considering cataract surgery, these tests help the doctor determine the potential visual acuity if the cataract was removed.  Testing potential acuity is especially helpful when considering cataract surgery for patients with retinal disease such as macular degeneration.  By performing this simple test, the amount of vision loss that can be attributed to the degeneration vs. the cataract can be determined. 

The glare testing permits one to assess the deterioration in vision that occurs with glare. Cataract can produce significant scattering of light. Hence people with early cataract may have good vision under ideal conditions of testing but the vision may deteriorate rapidly under conditions of glare. This testing enables one to decide on the need or otherwise for cataract surgery.

This is a very important test that enables one to calculate the desired power of intraocular lens during the cataract surgery. This artificial lens implanted in the same location as the natural lens permits one to have good vision without needing to use the thick glasses or contact lenses after cataract surgery. The test involves use of ultrasound to measure the length of the eyeball and this information along with keratometry (the measurement of the curvature of the cornea) is used to calculate the IOL power by a complicated formula.