Pavingstone degeneration

The choriocapillaris degenerates, with subsequent loss of retinal pigment epithelium. There is adherence between the remaining thinned retina and choroidal connective tissue. It is bilateral in approximately one third of cases and would appear to slowly progress over time. It is not inherited or associated with any systemic complications.

Symptoms

No symptoms are associated with this condition.

Signs

The lesions that characterise pavingstone degeneration are most commonly situated in the inferior quadrants of the fundus and lie between the equator and the ora serrata. They consist of groups of discrete yellow areas of chorioretinal thinning and atrophy, frequently surrounded by a border of pigmentation. Large choroidal vessels are sometimes seen crossing the lesions.

These atrophic patches may coalesce with time and the overlying vitreous is unaffected.

Prevalence

Pavingstone degeneration has been reported in approximately 30 per cent of people over the age of 20. It is more prevalent with increasing age or in eyes with increased axial length.

Differential diagnosis

Gyrate atrophy Lattice degeneration Congenital hypertrophy of the retinal pigmentary epithelium Retinal holes Inactive chorioretinitis lesions.

Dominant drusen

(Old synonyms: Doyne's honeycomb choroiditis, Tay's choroiditis) is a bilateral autosomal dominant-inherited condition. While the drusen are also seen as scattered yellow patches, they are closer to the posterior pole whereas pavingstone degeneration is more peripheral. The drusen are deposits of waste material in Bruch's membrane. There is a risk of choroidal neovascularisation and macular degeneration.

Management

Advice

No treatment is required for pavingstone degeneration. The main issue is the differential diagnosis, particularly with symptomatic retinal holes and horseshoe tears. Patients should be reviewed in line with their general ocular status.