Geographic chorioretinal atrophy in pseudoxanthoma elasticum

Area of Science:

• Ophthalmology
• Genetics
• Medical Imaging

Background:

• Pseudoxanthoma elasticum (PXE) is a rare genetic disorder affecting elastic fibers, primarily in the skin and eyes.
• Ocular manifestations of PXE include angioid streaks, peau d'orange, and choroidal neovascularization (CNV).
• Geographic atrophy (GA), a common cause of vision loss in age-related macular degeneration (AMD), has not been well-characterized in PXE.

Observation:

• This study retrospectively reviewed 41 eyes of 21 PXE patients at Vanderbilt Eye Institute.
• Eight eyes (20%) developed GA independent of CNV, with a mean follow-up of 3.5 years.
• All affected eyes exhibited pattern dystrophy, and 5 showed linear pigment deposits potentially predicting GA.

Findings:

• GA in PXE progressed at an average rate of 1.7 mm(2) per year, similar to AMD.
• Significant vision loss occurred in half of the affected eyes (ranging from 20/150 to 20/400).
• Linear pigmented pattern dystrophy was observed and may precede the development or progression of GA.

Implications:

• Isolated GA is a previously unrecognized complication of PXE that can cause substantial vision impairment.
• Early identification of GA and associated features like linear pigment deposits is crucial for patient management.
• Understanding GA progression in PXE is vital, especially with emerging therapies for GA.