To the Editor: The paper by Rigamonti et al. (Aug. 11 issue)* was timely, since cerebral cavernous malformations are being diagnosed more frequently by magnetic resonance imaging (MRI). The past five vascular malformations in children operated on at the Children's Hospital in Boston this year have been cavernous malformations, all of them symptomatic because of hemorrhage from the lesion associated with neurologic deficit, seizure, or both. We have been advocating the study of family members and siblings when there is a suggestive family history or when the patient has multiple lesions. Rigamonti et al. do not give us any recommendations,. © 1988, Massachusetts Medical Society. All rights reserved.