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EW GLAUCOMA 111 Researchers discover contrast sensitivity best predicts visual function V isual field testing and opti- cal coherence tomography (OCT) do not accurately indicate a glaucoma pa- tient's functionality, states a study published in the Archives of Ophthalmology. George L. Spaeth, M.D., Louis J. Esposito Research Professor, Wills Eye Institute of Jefferson Medical College, Philadelphia, and Jesse Richman, M.D., Wills Eye Institute, and colleagues evaluated 192 glau- coma patients for daily functioning ability using a performance-based test called the Assessment of Disabil- ity Related to Vision (ADREV) in order to learn which aspects of vi- sion most affect glaucoma patients. "Patients are interested in two things, how they feel and how they function," Dr. Spaeth said. "Health is a combination of those two things. If people feel well and func- tion well then they are healthy. Physicians often forget that because both of those things are hard to measure." Doctors attempt to determine how patients feel by taking their his- tory. More recently, specific ques- tionnaires have been developed to measure individuals' quality of life. But despite that information, patient functionality remains difficult to as- certain for numerous reasons. For in- stance, current methods largely depend on the patient's opinion, which can widely vary by a person's mood and overall mental state. "A lot of patients will take ques- tionnaires and different tests to as- sess functionality, and there's a lot of spread," Dr. Richman said. "You can have two people with the same level of vision, and one person thinks his vision is great and the other person thinks his vision is hor- rible." "Some people have amazing coping abilities," Dr. Spaeth added, commenting on why this phenome- non occurs. "Some individuals learn well how to fill in missing informa- tion, such as gaps in visual field. They learn to scan the field and move their eyes. Furthermore, the brain can adapt. 'Cortical plasticity' is a real phenomenon. However, as we know already, the ability of peo- ple to cope varies dramatically." Just like patient quality-of-life questionnaires, visual field testing and OCT, both of which play an im- portant role in diagnosing glau- coma, also have their shortcomings. Visual field testing may be a tried- and-true method of diagnosing glau- coma, but "there's a lot of scatter, a lot of noise," said Dr. Richman. "Many times you have to repeat the field to see if the apparent change is real." February 2011 March 2011 by Faith A. Hayden EyeWorld Staff Writer Contrast sensitivity tests key to glaucoma diagnosis The correlation of Pelli-Robson contrast sensitivity with the ADREV score was 0.80 (p<0.001). The correlation of integrated visual field with the ADREV score was -0.68 (p<0.001). Contrast sensitivity had a significantly (p<0.05) higher correlation with the ADREV score than visual field Source: Jesse Richman, M.D., and George L. Spaeth, M.D. continued on page 112 105-113 Glaucoma_EW March 2011_Layout 1 2/27/11 5:50 PM Page 111

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