ODs should take a measured approach to glaucoma management that considers the big picture, treat the disease carefully, assess all known risk factors, interpret results carefully, and more than anything else, use clinical evidence as a guide.
There is a commonly held but false belief within the general public that glaucoma only affects individuals over the age of 50. Experience has taught optometrists (ODs) to spot that myth from a mile away, but other untruths catch even the most practiced ODs off guard.
Edward Chu, OD, FAAO, and David Hicks, OD, FAAO, explored glaucoma facts and myths with research and evidence-based theories for glaucoma management during their lecture at the American Academy of Optometry annual meeting in Orlando.
Assessing and diagnosing
When assessing for glaucoma, it is important to keep in mind that while optic nerve size and shape matter, they do not indicate an increased risk for glaucoma, and normal variations in disc size can explain normal variations in cup-to-disc (C/D) ratios. Asymmetry in C/D values doesn’t necessarily indicate glaucoma either, Dr. Chu says.
When it comes to diagnosing glaucoma itself, it is important to note that glaucoma definitions fall on a spectrum.
According to Dr. Hicks, there are many ways to define and diagnose glaucoma. Optical coherence tomography (OCT) imaging, visual fields, and physical inspections of the optic nerve heads all contribute to variations.
Most glaucoma cases detected by ODs fall within the asymptomatic disease category in which progression can be detected by imaging tools.
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