More commonly unilateral although in about one third of cases, it presents bilaterally.
Affects elderly patients with coexisting cataract.
Clinical Features
Symptoms: usually asymptomatic
Signs:
Gray-white fibrillar material deposited on the surface of structures in the anterior chamber of the eye
The deposits produce three identifiable zones on the anterior lens capsule and are best seen when the pupil is dilated:
The translucent material deposit in the pupillary area which is quite faint and easily missed, outlined by dandruff-like deposits
More dense deposits of granular material at the peripheral zone
Clear intermediate zone, which is attributed to the posterior iris rubbing against the anterior lens capsule
The PXE material deposits on the zonules and ciliary processes may be associated with zonular weakness and lead to lens subluxation or zonular dialysis during cataract surgery
Increased pigment deposition at Schwalbe's line (i.e. Sampaolesi's line)
Deposits of flaky PXE material in the angle may compromise aqueous outflow and result in secondary glaucoma.
Open angle glaucoma is more common in patients with PXE (than in normal population) and may be more resistant to medical therapy.
Management
Regular follow-up of patients (including those with normal intraocular pressures and optic discs)
Topical and/or systemic anti-glaucoma medications are initially used to treat patients with increased intraocular pressure
Surgical treatment (including laser trabeculoplasty and filtration surgery) may be indicated for glaucoma resistant to medical therapy