Cerebral Cavernous Malformations

To the Editor.  —In the February 1989 issue of the Archives, Allard et al¹ described several members of a family who had multiple lesions noted on magnetic resonance imaging that were termed arteriovenous malformations. These lesions, however, have the characteristic magnetic resonance imaging appearance of cavernous malformations (angiomas), another type of cerebral vascular malformation.²Cerebral cavernous malformations are masses of abnormally dilated vascular spaces with no intervening brain parenchyma.^3,4 These lesions, once regarded as rare, are being diagnosed with increasing frequency with magnetic resonance imaging. In the past, cavernous malformations have often been diagnosed as thrombosed arteriovenous malformations.⁵ There is a sporadic and a familial form of cerebral cavernous malformation.⁴ The sporadic form accounts for approximately 50% of cases and is typically associated with a single lesion.⁴ The familial form of the disorder is common in Mexican-American families, is inherited as an autosomal dominant