[Central areolar choroidal dystrophy with retinal crystals]

Genotype-phenotype correlations and differential diagnosis in autosomal dominant macular disease

In the past few years, great progress has been made in the understanding of macular diseases. A number of disease-causing genes have been cloned, and numerous loci for other conditions have been mapped. The purpose of this article is to provide an overview of the current understanding of the genotype-phenotype correlations in autosomal dominant macular diseases with an emphasis on differential diagnostic issues. Whenever possible, the molecular correlates have been reviewed and the implications for age-related macular degeneration have been discussed. The many similarities of these diseases to age-related macular degeneration of the atrophic or exudative type, which can be misleading in elderly subjects, have also been addressed. While some conditions yield disease truly confined to the macula, others show widespread retinal involvement on functional testing. Clear-cut genotype-phenotype correlations are possible only for some forms of macular diseases. To further complicate the diagnostic process, there is a considerable degree of clinical overlap between many of them, making the differential diagnostic process potentially challenging. Functional testing, careful assessment of family history and extensive family work-up are essential in differentiating at the clinical level most, but not all, of these disease entities. Awareness of all of these conditions is required to direct correctly diagnostic investigations, to formulate an accurate prognosis, and for proper genetic counseling.

Full-field electroretinograms in patients with central areolar choroidal dystrophy

Patients with central areolar choroidal dystrophy are often difficult to diagnose because they are similar in fundus appearance to other retinal disorders. Nineteen patients with the diagnosis were studied in order to estimate the diagnostic and prognostic value of full-field electroretinography in this disorder. Our results showed that the cone b-wave amplitude in the ERG is decreased, that there is a progression in this decrease during a follow-up period of 5 years, and that the cone b-wave implicit time is prolonged. Central areolar choroidal dystrophy is considered to be primarily a choroidal disease. Our results indicate that it also affects most or all of the retinal cones. Further, our observations suggest that the disease is slowly progressive and that full-field electroretinography is of value in its early diagnosis.

A variant of central areolar choroidal dystrophy

This article describes the variable ophthalmoscopic features of a macular disorder in five generations of one family. This disease shares similarities with central areolar choroidal dystrophy and other progressive dominant macular dystrophies but demonstrates significant differences that required further consideration. The milder affected individuals had confluent hyperfluorescence around the macular area while the more severe lesions consisted of marked chorioretinal atrophy of the macula. The visual fields revealed a central scotoma. The disorder was transmitted as an autosomal dominant trait.