White matter integrity and its correlation to seizures in diffuse glioma

Seizures are one of the most common symptoms in patients with diffuse glioma, occurring in 30-80 % of cases. Although seizure control can be achieved in up to 90 %, seizures remain a significant burden and are hardly predictable. The aim of this analysis was, therefore, to investigate the association between white matter integrity and seizure occurrence in patients with diffuse glioma using diffusion tensor imaging (DTI).

Patients with first diagnosis of diffuse glioma (WHO-grade 2, 3, 4) who received preoperative DTI sequences for surgical planning were analyzed. Tractography of corpus callosum and cingulum was carried out, extracting mean FA values of the resulting volumes.

50 patients (17 female) were included with a mean age of 59.5 ± 2.2 years. Glioma WHO grade 4 was most common (82 %), followed by grade 3 (10 %) and grade 2 (8 %). Most gliomas were located left temporal (32 %) and bilateral frontal (each hemisphere 16 %). 16 % presented with multifocal glioma. 48 % had suffered seizures prior to surgery, and were thus diagnosed with structural epilepsy. 22 % of all patients presented recurring seizures despite surgery and anti-seizure medication, and 6 % developed new seizures after surgery. After correction for multiple comparisons, increased FA in the left parahippocampal cingulum was significantly associated with preoperative seizures (0.30 ± 0.01 versus 0.27 ± 0.01, p_corr = 0.007), while increased FA in the forceps minor of the corpus callosum correlated with postoperative seizures (0.49 ± 0.01 versus 0.43 ± 0.01, p_corr = 0.014).

Higher preoperative white matter integrity was associated with increased risk for occurrence of seizures in diffuse glioma. Further research is warranted to investigate the relation with tumor pathology.