Analysis of insular lobe sensory and threshold stimulation intensities based on stereo-electroencephalograph / 中华神经医学杂志

ABSTRACT

Objective To explore the insula sensory features and analyze its electrophysiological characteristics based on stereo-electroencephalograph (SEEG).Methods The clinical data of 16 drug-refractory epilepsy patients,admitted to our hospital from December 2013 to June 2016,were retrospectively analyzed.All patients were implanted with SEEG electrodes;totally,34 electrodes (257 contacts) located in insular lobe.Micro current stimulation was performed every adjacent two contacts to get the sensory mapping and the stimulus threshold of the insula.Results Of all the 257 contacts,160 presented clinical symptoms (positive contacts);there were 149 contacts with sensory manifestations,of which 72 were on the left side and 77 on the right.Sensory symptoms of insula mainly included both somatic sensation and visceral sensation.The threshold of somatosensory was (4.9±2.9) mA,and the threshold of visceral sensation was (6.0±2.9) mA,without significant difference (P＞0.05).No significant difference was noted between the left insula sensory ([6.2±3.1] mA) and the right insula sensory ([5.7±2.8] mA,P＞0.05).It showed sensation abnormal of larynx,lingua,face and limb when the middle and posterior short gyrus,as well as anterior and posterior long gurus,respectively,were stimulated;insula sensory showed anatomy distribution,with different stimulated sensitivities.The sensory function showed parallel distribution with the insular gyrus from the middle short gyrus to posterior long gurus,as laryngeal-lingual-facial (nasal and lips)-limb sensation,and the thresholds of the five insular gurus were (6.0±3.1) mA,(4.7±1.5) mA,(8.0±2.9) mA,(5.1±2.4) mA and (4.5±2.6) mA,respectively,with statistically significant differences (P＜0.05).Conclusions The sensitivity of somatic sensation and visceral sensation of the insula monitored by SEEG is similar,as well as the left and right side.The sensory threshold and sensory fan-shaped distribution play important roles in conforming insular symptoms and location for clinician.