Objectives: To define the frequency of retinal lesions in a large panel of patients with familial cerebral cavernomas and to screen the cerebral cavernous malformation genes in patients with cerebral and retinal lesions.
Methods: Fundus examination was proposed to each of the index patients of 70 families with cerebral cavernous malformation who have been included in a prospective clinical and neuroradiological follow-up. All of the coding exons of the KRIT1, MGC4607, and PDCD10 genes were screened as previously described.
Results: Of the 70 index patients, 60 were consecutively examined. The 10 remaining patients refused the fundus examination. Three of the 60 examined patients had a retinal cavernoma diagnosis. Three mutations were found: a point mutation within exon 5 of the KRIT1 gene, a large deletion that encompassed exons 1 and 2 of the MGC4607 gene, and a large genomic de novo deletion encompassing the whole PDCD10 gene.
Conclusions: Retinal cavernoma frequency can be estimated to be about 5% of the patients with familial cerebral cavernomas. Retinal cavernomas are not restricted to KRIT1 mutation carriers but can be observed in patients carrying a mutation in any of the 3 cerebral cavernous malformation genes.
Clinical relevance: Five percent of patients with familial cerebral cavernomas have retinal cavernomas. These lesions are clinically asymptomatic. They can be associated with any of the 3 cerebral cavernous malformation genes.