Incidence, clinical presentation and imaging findings of cavernous malformations of the CNS A twenty-year experience

QUESTIONS UNDER STUDY: Up to 88% of cavernous malformations (CMs) of the central nervous system can become symptomatic and cause long-term disability. The aim of this study was to document the characteristics of CMs in the catchment area of our institution. METHODS: We retrospectively analysed newly discovered CMs over a 20-year observation period, as well as the frequency of familial forms in the catchment area. RESULTS: In the period from 1985-2004, a total of 347 patients were investigated. The cohort included about 75% symptomatic CM cases. A total of 1.31 and 0.55 symptomatic and asymptomatic cases, respectively, were newly diagnosed per annum per 100'000 inhabitants. Symptomatic CMs were diagnosed on average at the age of 36 years (range: newborn to 79 years old). There were slightly more patients who presented with evidence of acute bleeding (28%) than those with seizures (26%). Most intracranial lesions were supratentorial in location (54%). Lesion size was predominately below 3 cm (range: 0.2 to 8 cm). Symptomatic CMs (average: 1.75 cm) were significantly larger (p < .0001) than asymptomatic ones (average 0.91 cm). When compared to medical literature, there was a relatively high frequency of multiple CMs (18.9%), which were more common in the familial form (62%). CONCLUSIONS: The observed frequency of CM, including multiple lesions in a single individual and the familial form of this pathological entity appears relatively high compared to medical literature.