<prompt> A 75 year old patient presents with deterioration of vision. On examination the pupillary reflex is observed to be sluggish and the Intraocular pressure is normal. Optic disc evaluation shows a large and deep cup and primarily shows paracentral scotomas. The most likely diagnosis is:Primary Narrow Angle glaucomaNormal Tension GlaucomaNeovascular GlaucomaAbsolute Glaucoma  <response>: B i.e. Normal Tension Glaucoma - Primary open angle glaucoma POAG or chronic simple glaucoma CSG is commonest type of glaucoma that presents with bilateral, adult onset increased KW 21 mm Hg, open angle on gonioscopy, optic nerve damage large deep cup cupping and visual field defects scotomas. Thin cornea is a known risk factorQ. - All features of POAG in a patient with normallow intraocular tension i.e. 21 mm Hg suggest the diagnosis of normal tension glaucoma NTG or low tension glucomaQ. Glucoma patients may have sluggishabsent papillary reflexQ. 