We found cavernous angiomas (CA) in 10 of 22 members of a large Hispanic family. The proband had seizures, and a CA was found at surgery. He and two sisters with seizures had normal angiograms, but CT or MRI showed lesions compatible with CA. Similar abnormalities were found in two cousins with seizures and 5 of 17 asymptomatic relatives studied. MRI proved to be more sensitive than CT for identifying CA. Hispanic families appear to have a predisposition for dominantly inherited CA of the brain.