Abstract
Objective
The objective of this study was to identify risk factors associated with surgery-related neurological morbidity in patients with drug-resistant epilepsy undergoing supra-sylvian operculo-insular resections. As secondary outcomes, we also analyzed the risk factors for ischemic lesions (IL) of corona radiata and seizure recurrence.
Methods:
A retrospective analysis was conducted on a cohort of patients underwent supra-sylvian operculo-insular resections for drug-resistant epilepsy. The association of several presurgical, surgical and post-surgical factors with both primary (persistent neurological deficits) and secondary (structural abnormalities on postoperative MR imaging and seizure recurrence) postoperative outcomes, were investigated with univariate and multivariate statistical analysis.
Results:
The study included a total of 65 patients. 46.2% of patients exhibited postoperative neurological deficits only 12.3% experienced persistent deficits. On postoperative MRI, IL in the corona radiata and cortico-spinal tract Wallerian degeneration (CSTWd) were seen in 68% and 29% of cases, respectively. Only CSTWd was significantly associated with persistent neurological deficits (RR 2.6). Combined operculo-insular resection (RR 3.62) and surgery performed on left hemisphere (RR 0.37) were independently associated with IL in the corona radiata. Variables independently associated with CSTWd were the presence of malacic components in the IL (RR 1.96), right central operculum resection (RR 1.79) and increasing age at surgery (RR 1.03). Sixty-two patients had a postoperative follow-up >12 months [median 56 (IQR 30.75-73.5)] and 62.9% were in Engel’s class I at last outpatient control. The risk of seizure recurrence was reduced by selective opercular resection (RR 0.25) and increased by the histological diagnosis of aspecific gliosis (RR 1.39).
Significance
This study provides insights into the risk factors associated with surgery-related neurological morbidity, as well as further evidence on the postoperative occurrence of subcortical injury and seizure recurrence in epileptic patients undergoing supra-sylvian operculo-insular resections. The findings highlighted in this study may be useful to better understand the processes supporting the increased surgical risk in the operculo-insular region.
DIC