She is myopic and wears glasses. She is now almost blind. What is the SINGLE most likely diagnosis?

A 32 year old woman has progressive decrease in vision over the past 3 years on both eyes. She is myopic and wears glasses. She is now almost blind. What is the SINGLE most likely diagnosis?

A. Cataract
B. Glaucoma
C. Retinopathy
D. Uveitis
E. Keratitis

The symptoms and progressive decrease in vision and myopia point towards openangle glaucoma. Although the age does not correlate with open-angle glaucoma as it is very rare before the age of 40, the other options given are much less likely.

Simple (primary) open-angle glaucoma is present in around 2% of people older than 40 years. Other than age, risk factors that need to be known for PLAB include: - family history - black patients - myopia

Note: The incidence increases with age, most commonly presenting after the age of 65 (and rarely before the age of 40).

Unfortunately, in the vast majority of cases, patients are asymptomatic. Because initial visual loss is to peripheral vision and the field of vision is covered by the other eye, patients do not notice visual loss until severe and permanent damage has occurred, often impacting on central (foveal) vision. By then, up to 90% of the optic nerve fibres may have been irreversibly damaged

Open-angle glaucoma may be detected on checking the IOPs and visual fields of those with affected relatives. Suspicion may arise during the course of a routine eye check by an optician or GP, where abnormal discs, IOPs or visual fields may be noted.

Features may include - peripheral visual field loss - nasal scotomas progressing to ‘tunnel vision’ - decreased visual acuity - optic disc cupping