Authors :
Presenting Author: Sunao Oe, MD – Japan Red Cross Wakayama Medical Center
Yasuo Nakai, MD,PhD – Wakayama Medical University; Hiroki Nishibayashi, MD,PhD – Wakayama Medical University; Tomohiro Donishi, MD,PhD – Wakayama Medical University; Yoshiki Kaneoke, MD,PhD – Professor, Wakayama Medical University; Naoyuki Nakao, MD,PhD – Professor, Wakayama Medical University
Rationale: Cingulate cortex has recently proposed a four-region neurobiological model based on structural, circuitry, and functional imaging observations (Palomero-Gallagher N, et al. Hum Brain Mapp. 2009). We experienced the two patients with intractable epilepsy involving cingulate cortex who were performed resting-state functional connectivity magnetic resonance imaging (rs-fcMRI) analysis in order to explore individual characteristic network.
Methods: Rs-fcMRI (TR=3.0sec, 5 min×3) was performed for the two patients with intractable epilepsy involving cingulate cortex, who underwent electrocoticography grid placement and resection to explore individual characteristic network. We determined local network value of degree centrality (DC) and global network value of eigenvector centrality (EC) for each region based on age-matched 360 healthy females (Donishi T et. al. Brain and Behav. 2018, Nakai Y et. al. Sci Rep, 2021). Significant level was defined at the values of mean ± 2SD (e.g., “high” means >mean+2SD).
Results: The patient 1 involving the anterior cingulate cortex (ACC) showed focal impaired awareness seizure with integrated goal-oriented behavior and ictal pouting. Rs-fcMRI analysis revealed high functional connectivity between the ACC and the face motor cortex, mesial and lateral prefrontal cortex, and amygdala. High DC next to seizure onset zone (SOZ) were detected before surgery and normalized after surgery. High DC in posterior cingulate cortex (PCC) were detected before and after surgery. High EC next to SOZ and in posterior cingulate cortex were detected before surgery normalized after surgery. The patient 2 involving the mid-cingulate cortex (MCC) showed focal aware seizure with asymmetric tonic posturing, ictal body-turning, and twisting. Supplementary motor area syndrome and impulsive goal-oriented behaviors were also observed transiently after surgery. Rs-fcMRI analysis revealed high functional connectivity between the MCC and the mesial and dorsal premotor areas, and thalamus. High DC next to SOZ were detected before surgery and normalized six months after surgery. High DC detected in premotor cortex, PCC, and basal ganglia after surgery, and in premotor and posterior cingulate cortex were normalized 12 months after surgery. High EC was not detected next to SOZ, but were also detected in premotor cortex, PCC, and basal ganglia after surgery, and in premotor and thalamus were normalized 12 months after surgery.
Conclusions: Some regions with high DC were detected next to SOZ in both patients, whereas high EC was only detected in patient 1, which corresponded to the ECoG findings. The contralateral ACC and MCC in patient 2 had high functional connectivity in the course of the recovery from postoperative transient disability. Rs-fcMRI explored different epileptic network patterns according to the focus location of the cingulate cortex, and dynamic network alterations including default mode network were observed after surgery in both cases. Default mode network and basal ganglia may play an important role to recover the functional network after removing some extent of epileptogenic zone in the cingulate cortex.
Funding: None