A 65-year-old man presents with a right IOP of 35mmHg, advanced optic disc cupping and visual field loss. There is a past ophthalmic history of blunt trauma to that eye. What’s going on here?
Angle recession glaucoma (ARG) is a secondary open-angle glaucoma associated with blunt ocular trauma. Some people who suffer blunt ocular trauma develop angle recession glaucoma and vision loss days, months or even years later. There are reports of glaucoma developing up to 50 years after the injury!
The underlying mechanism? Blunt trauma forces aqueous humor laterally and posteriorly against the iris leading to traction on the iris root and to a tear between the longitudinal and circular muscles of the ciliary body. Sometimes, the ciliary arteries can be broken, leading to a bleed (hyphema). This trauma may damage the trabecular meshwork and Schlemm’s canal leading to an early spike in intraocular pressure. However, long term scarring and fibrosis in this vicinity can lead to elevated pressure years later.
It has been reported that the greater the number of clock hours of angle recession, the greater the likelihood of developing elevated pressures and glaucoma.
This does look like a case of angle recession glaucoma. The key exam finding in angle recession is widening of the ciliary body band that is seen on gonioscopy. Most optometrists are not skilled in this technique, so an emergency referral to an ophthalmologist for further investigation is required.
My main learning from this question is to ask patients about any history of blunt trauma to one or both eyes no matter how long ago and if the answer is affirmative, to follow this up with intraocular pressure measurement and a very good look at the optic nerve head.