Optic Disc Evaluation in Glaucoma
Glaucoma, by definition, is chronic, progressive optic neuropathy.[1-3] Structural damage to the optic nerve head (ONH) is a characteristic feature of glaucoma and precedes visual field loss in most cases. Para-papillary changes may also be observed in eyes with glaucoma. The mere presence of raised intraocular pressure is not glaucoma. Hence, the optic disc evaluation is the first and most important step in diagnosing glaucoma. [4, 5] Subjectivity and overlap in appearance of the normal and glaucomatous optic disc make ONH evaluation challenging. Subtle changes may also be missed easily. Adequate training and experience are required to determine minor abnormalities in the ONH accurately. [6] Examination of the optic disc Direct ophthalmoscopy, Slit lamp biomicroscopy with a handheld +66, +78 or +90 dioptre aspheric convex lens or Hruby lens, or a contact lens (Goldmann lens) or Indirect ophthalmoscopy may be done to examine the ONH. The pupil should be dilated prior to the examination
Dr. Chandrima Paul · Dr. Divya J