Hypersalivation in temporal lobe epilepsy

We sought to determine whether hypersalivation helps lateralize seizure onset during complex partial seizures of temporal lobe origin. Several clinical signs, which help lateralize seizure onset, have been reported in temporal lobe epilepsy (TLE). Increased salivation only occasionally has been reported as a manifestation of partial epilepsy.

Of 590 consecutive patients admitted for video-EEG monitoring, either as a part of a presurgical evaluation of medically intractable epilepsy or for diagnosis and clarification of their paroxysmal symptoms, we identified 10 patients with ictal hypersalivation as a prominent manifestation of complex partial seizures. We reviewed the clinical features, scalp-sphenoidal video-EEG monitoring, intracarotid amytal (Wada) testing, hippocampal volumetric magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography (FDG-PET) scans of these patients.

Of the 10 patients with ictal hypersalivation, seven patients had nondominant/right TLE, and three patients had dominant/left TLE. All patients had hippocampal atrophy on volumetric MRI. Eight of the 10 patients underwent standard temporal lobectomy with amygdalohippocampectomy (six right, two left). All of the operated-on patients had a seizure-free (Engel class I) outcome, and their increased salivation resolved. Two patients, who did not undergo surgical treatment, continue to have complex partial seizures with increased salivation.

We conclude that increased salivation as a prominent ictal finding in complex partial seizures of temporal lobe origin is more likely to be of nondominant temporal lobe origin. Further studies with larger numbers of patients are needed to replicate this finding.