Introduction: Many patients with chronic subdural hematoma present transient neurological symptoms. While most of them typically receive a diagnosis of epilepsy, we believe a significant proportion of these patients rather suffer from cortical spreading depolarization (CSD) and do not benefit from conventional epilepsy management.
Methods: We performed a retrospective case-control study comparing clinical features of patients with transient neurological symptoms post-SDH evacuation between groups with negative versus positive EEG (ictal or interictal anomaly). Using our results, we built a diagnostic score which predicts the EEG result and could inform proper management.
Results: 59 patients were included, of which 20 (34%) had a positive EEG. Positive symptoms (OR 0.05, p<0.0001), complete response to standard AED (OR 0.06), speech-related symptoms (OR 4.8, p=0.018), prolonged episodes (OR 23.1, p=0.001), clonic movements (OR 0.014, p<0.0005), impaired awareness (OR 0.013, p<0.0005), mortality (OR 0.021, p=0.003) and favourable outcome at follow-up (OR 4.8), were discriminative between our groups, with odds ratios >1 favouring negative EEGs. Using our results, we built a clinical score predicting EEG result based on clinical criterias, which showed a 90% sensitivity and 100% specificity, retrospectively. This suggests the existence of two separate subgroups within patients with transient neurological symptoms following SDH: one with epilepsy, and one with another phenotype, which we attribute to CSD.
Conclusions: We believe that the differences observed between our groups, have most likely been driven by the presence of CSD, in our case group. Our clinical score showed a promising diagnostic value, which may render useful for future prospective trials, regarding CSD in SDH.
Patient Care: This study proposes a new etiology for transient neurological symptoms in patients with chronic subdural hematoma
Learning Objectives: Discuss transient neurological symptoms in patients with chronic subdural hematoma