A Distinctive, Sharply-Bordered Pattern of Central Retinal Thinning
Central areolar choroidal dystrophy is a rare inherited condition marked by a well-defined, roughly circular area of thinning affecting the macula and the choroid — the layer of blood vessels beneath the retina that supplies it with oxygen and nutrients. The name reflects its most distinctive feature on examination: a sharply bordered ('areolar') zone of atrophy centered on the macula, which sets it apart from several other macular dystrophies that tend to have less clearly defined edges.
Onset is typically in adulthood, often the 30s to 50s, though it can begin earlier in some families. Central vision blur is the primary symptom, usually progressing slowly over years rather than months. Colour vision can become noticeably affected as the condition advances, particularly the ability to distinguish subtle shade differences. Because the area of change is centered specifically on the macula, peripheral vision and night vision are generally well preserved even as central, detailed vision declines.
Central areolar choroidal dystrophy has been linked to mutations in a small number of genes, most notably PRPH2 (peripherin-2), which is also implicated in some other retinal conditions, reflecting its broader role in maintaining healthy photoreceptor structure. Inheritance is most commonly autosomal dominant, meaning a single mutated copy from either parent is enough to cause the condition, and it typically appears in multiple generations of an affected family, though the age of onset and severity can still vary between relatives who share the identical mutation.
The sharply demarcated area of atrophy is often visible on standard fundus photography and is characterized further with optical coherence tomography, which shows thinning of both the retina and the underlying choroid within the affected zone. Fundus autofluorescence highlights the borders of the atrophic area clearly, which is useful both for diagnosis and for tracking any gradual expansion over time. Fluorescein angiography can help visualize the reduced blood flow through the thinned choroid. Genetic testing for PRPH2 and related genes can confirm the diagnosis and clarify the inheritance pattern for the wider family.
There's currently no treatment that reverses the choroidal and retinal thinning in central areolar choroidal dystrophy, so management centers on regular monitoring to track the size and progression of the affected area, along with low-vision support as central vision declines. Protective eyewear against UV light is commonly recommended, following similar reasoning applied across many inherited retinal conditions. Because progression is typically slow, many people are simply monitored at intervals for years without other active intervention, and are encouraged to stay aware of clinical trials as gene-specific research in inherited choroidal and retinal conditions continues to expand.
Progression is generally slow, often unfolding over one to several decades, and most people retain functional peripheral vision even as central vision changes. Because the condition is uncommon and relatively recently well-characterized compared to some other macular dystrophies, ongoing research into its precise genetic underpinnings continues to refine what's understood about long-term outlook.
Its most distinctive feature is a sharply bordered, roughly circular zone of thinning affecting both the retina and the underlying choroid, which looks notably different on imaging compared to the more diffuse or flecked patterns seen in several other macular dystrophies.
It often does expand gradually, though the pace varies significantly between individuals — this is one of the main things regular monitoring with imaging like fundus autofluorescence is used to track.
Generally no, at least not significantly — because the area of change is centered specifically on the macula, peripheral (side) vision and night vision are usually well preserved even as central vision declines.
Yes — since the condition is most commonly inherited in an autosomal dominant pattern, genetic testing can clarify risk for other relatives, which is often a helpful step for family planning and early monitoring discussions.