[Lessons learnt from 101 hemispheric pediatric epilepsy surgeries part ii: pitfalls and complications]

To evaluate the spectrum of pitfalls and complications after hemisherotomy basing on a retrospective study of a large consecutive pediatric cohort of patients from a single institution.

One hundred and one patients (med. age - 43 months) with refractory seizures underwent hemispherotomy. Developmental pathology was the anatomical substrate of disorder in 42 patients. The infantile post-stroke scarring and gliosis was the origin of epilepsy in the majority of 43 cases with acquired etiology. The progressive pathology (RE, S-W and TS) was the etiology in the rest of children (16 cases). The lateral periinsular technique was used to isolate the sick hemisphere in 55 patients; the vertical parasagittal approach was employed in 46 cases. Median perioperative blood loss constituted 10.5 ml/kg, but was markedly larger in kids with hemimegaly (52.8 ml/kg); 57 patients needed hemotransfusion during surgery. Median length of stay in ICU was 14.7 hours, and the length of stay in the hospital until discharge - 6.5 days. Eight patients underwent second-look surgery to complete sectioning of undercut commissural fibers. FU is known in 91 patients (med. length - 1.5 years).

Major surgical complications with serious hemorrhage and/or surgery induced life-threatening events developed in 7 patients (one of them has died on the 5^th day post-surgery for the causes of brain edema and uncontrolled hyponatremia). Various early and late infectious complications were noted in 4 cases. Ten patients experienced new not anticipated but temporary neurological deficit. Nine patients needed shunting for the causes of hydrocephalus within several first months post-hemispherotomy. Early seizure onset was associated with probability of all complications in general (p=0.02), and developmental etiology - with intraoperative bleeding and hemorrhagic complications (p=0.03).

Children with developmental etiology, particularly those with hemimegalencephaly, are most challengeable in terms of perioperative hemorrhage and serious complications. Patients with relapse or persisting seizures should be evaluated for the possibility of incomplete hemispheric isolation and have good chances to become SF by re-doing hemispherotomy.