A 48-year-old woman presents with gradual painless visual loss. Fundoscopy reveals a cup-to-disc ratio of 0.9 with focal notching of the inferior rim. Visual field testing shows an arcuate scotoma. Gonioscopy confirms open angles bilaterally. IOP is 18 mmHg. Which diagnosis best explains this presentation?

• A Non-arteritic anterior ischaemic optic neuropathy
• B Acute primary angle-closure glaucoma
• C Optic nerve sheath meningioma
• D Primary open-angle glaucoma with normal baseline IOP ✓

Explanation

This patient has normal tension glaucoma, a subset of POAG, characterised by glaucomatous optic neuropathy (focal rim notching, increased cup-to-disc ratio) and corresponding visual field defects despite IOP within the statistical normal range. The open angles on gonioscopy rule out angle closure. AION presents with altitudinal field loss and disc oedema, not progressive cupping. Meningioma causes progressive loss without cupping.

Reference: The Glaucoma Book, 2nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.