Purpose: To characterize the clinical phenotypes and genotype of a large family with North Carolina macular dystrophy (NCMD). Design: Observational, retrospective case series. Participants: Thirteen participants who were at risk of inheriting a dominantly transmitted disease gene from a 4-generation family from Baltimore were examined. Methods: Thirteen participants underwent ophthalmic examination and genomic linkage analysis. Fundus photography, spectral-domain optical coherence tomography (SD-OCT), fluorescein angiography, ultrasonography, full-field electroretinography, and electro-oculography were performed on some patients. Main Outcome Measures: Description of clinical phenotypes with genomic linkage to the MCDR1 locus. Results: Nine of 13 participants were affected with NCMD. There are variable and previously unreported clinical manifestations among affected individuals with NCMD, including drusen, macular staphyloma, choroidal neovascularization, a retinal pigment epithelial tear, and geographic atrophy. The distinctive and virtually pathognomonic grade 3 lesions in NCMD are neither staphylomas nor colobomas, as previously thought. As shown by ultrasonography and SD-OCT, they are deep chorioretinal excavations not involving the sclera, for which the authors propose a new term: macular caldera. Linkage analysis was performed, and the disease-causing gene in this family was mapped to the MCDR1 locus. Conclusions: North Carolina macular dystrophy has a wide spectrum of clinical phenotypes that resemble age-related macular degeneration except for their early age of onset. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
ASJC Scopus subject areas