Ophthalmoscopy still the key to glaucoma diagnosis

Baseline optic disc photographs remain an essential tool in the diagnosis of glaucoma, said George Spaeth MD, Wills Eye Hospital, Philadelphia, Pennsylvania, USA. “The ideal diagnostic test is that it to be valid and relevant diagnosis allows staging and provide a permanent baseline against which future tests can be compared. It should be readily available everywhere, it should not require instrumentation which is expensive and difficult to maintain and should be easily learned and easily interpreted,” Dr Spaeth told the 7^th World Glaucoma Congress in Helsinki, Finland.

The ideal diagnostic test is that it to be valid and relevant diagnosis allows staging and provide a permanent baseline against which future tests can be compared

He noted that identifying glaucoma through ophthalmoscopy is a skill that one can acquire through viewing of optic discs of patients who definitely have glaucoma. He suggested that rather than deconstructing the images and looking for specific features like disc haemorrhages, one should learn to recognise the patterns they have in common. He likened it to the way art critics learn to identify the artist who painted a painting that they haven’t seen before. He also maintained that data from newer imaging technologies like optical coherence technology (OCT) and Heidelberg Retinal Tomography (HRT) instruments is not truly diagnostic regarding glaucoma. Opinions vary on the threshold thinness of the retinal nerve fibre layer (RNFL) for glaucomatous damage. Moreover, there are other pathologies which also cause RNFL thinning like myopia.