Abstracts

Rationale: Temporal encephaloceles (TEs) are herniations of the temporal lobe brain parenchyma through the dura mater and skull that have recently been postulated to represent a potential seizure focus in some patients with epilepsy. The presence of TEs has been associated with increased intracranial pressure in some circumstances, and although patients with TEs have been shown to have certain clinical and radiologic characteristics suggestive of idiopathic intracranial hypertension (IIH), the prevalence and characteristics of headaches in these patients remains elusive. Our aim was to determine if headaches consistent with IIH and in general were more prevalent in patients with vs without TEs among patients with epilepsy.  Methods: Electronic medical records were reviewed retrospectively. Among the 474 patients with epilepsy, 103 patients (21.7%) had at least one TE diagnosed on initial MRI or on retrospective review by a board-certified neuroradiologist (MY), while 371 patients had no TE present. The patients were grouped into one of four categories depending on their headache characteristics (IIH-like, peri-ictal, other, or no headaches). Analysis of the categories was performed using a Fisher Exact test.  Results: Among 474 patients with epilepsy, 103 (21.7%) patients were identified as having a TE. Patients with TEs were more likely to experience headaches of any type than no headaches (p< 0.00001) and more likely to experience IIH-like headaches than to have other headaches or no headaches compared to patients without TEs (P< 0.00001). Interestingly, patients with TEs were also more likely to experience peri-ictal headaches compared to patients without TEs (p<0.005). However, patients with TEs were no more likely or unlikely to have other (non-IIH) headaches vs no reported headaches (p=1). While the TE group was more likely to have headaches of any type than the non-TE group, the similar rates of other headaches or no headaches among the two groups further supports our methodology, since one would expect that patients with or without TEs would develop other headache syndromes at similar rates. A total of 25 patients underwent lumbar puncture with OP, and while no difference was observed in elevated or normal OP in patients with or without TEs (p= 0.1175), there was a trend toward patients with TEs having elevated OP (66.7%) compared to elevated OP in patients without TEs (28.5%).  Conclusions: Headaches with features of IIH (P< 0.00001) and peri-ictal (P<0.0001) headaches were more commonly seen in patients with epilepsy who had TEs identified on imaging vs those without TEs. We found that there was a relationship among epileptic patients with TEs and headache characteristics consistent with IIH. These patients could possibly benefit from more aggressive screening methods to manage elevated intracranial pressure to further prevent disease process. Funding: No funding