Surgery-related outcome is presented in Tables 2 and 3. As for superficial cavernomas (Fig. 1) (Table 2), 21 cases out of 39 (54 %) operated in the rolandic/perirolandic cortex showed post-operative neurological deficits: in 16 patients the deficit disappeared within 6 months; 5 patients (13 %) developed permanent deficits, 3 of them with a mild disability (mRS 1–2) and 2 with a significant disability (mRS > 3) (as a consequence of previous hemorrhage in one). Only transient deficits were reported in 14 patients operated on in the speech area, mostly lasting for less than 1 month (64 %). After surgery in the visual cortex, in 4 cases (55.5 %) a visual deficit was present transiently and in only one case it was permanent (quadrantopsia).

As for deep cavernomas (Table 3), 9 of the 14 patients operated on in the insula (Fig. 2) showed post-operative deficits that were transient in 5 cases (55 %) and permanent in 4 cases, with significant disability (mRS > 3) in 2 patients (22 %). As for intraventricular cavernomas (Fig. 3), 3 cases (50 %) out of 6 patients showed post-operative deficits (2 permanent but not disabling). As for basal ganglia cavernomas, 9 patients (90 %) showed neurological deficits that were transient in 1 case (disappearing within 30 h), mild (mRS 1–2) in 6 cases and disabling (mRS > 3) in 2 cases. Statistically, surgery for superficial lesions carried a lower risk of post-operative deficits as compared to deep lesions (p = 0.02), with a highly significant difference in the incidence of permanent deficits (p < 0.0001).

Epilepsy at follow-up is presented in Table 4, according to the Maraire scale [16]; as a whole, favorable results (Maraire 0) were observed in 44 % of cases, with no seizures and no therapy at follow-up. Moreover, of 15 patients with early post-operative seizures, 13 were seizure-free without therapy at follow-up.