Spiders, ladybugs and bees: A case of unusual sensations in a child with cingulate epilepsy

Posterior Cingulate Epilepsy: A Systematic Review

SUMMARY

In this review, authors discuss epilepsy originating from posterior cingulate regions, a challenging entity to diagnose and most likely underrecognized. A systematic review of posterior middle and posterior cingulate epilepsy cases was conducted to present a summary of current knowledge about this localization-based type of epilepsy. The literature search identified 32 articles, for a total of 69 patients (34 with posterior middle cingulate epilepsy [pMCE] and 35 with posterior cingulate epilepsy [PCE]). Most patients were children and young adults with drug-resistant lesional epilepsy with high seizure burden. In both groups, most patients reported auras, mainly sensory, but various types were reported, including autonomic, behavioral, and cognitive manifestations. Most pMCE and PCE showed motor manifestations (mainly respectively asymmetric tonic posturing and automotor features). Impaired awareness during seizures was more frequently reported in PCE than in pMCE. As for ictal scalp EEG, epileptogenic abnormalities were poorly lateralized and did not localize the seizure onset zone. An ictal temporal involvement was only observed in PCE. Interictal EEG findings were nonspecific. As for other presurgical noninvasive investigations, data are limited, and no studies have adequately assessed their value. Partly explained by our inclusion criteria, most patients underwent a surgical procedure (either lesionectomy or resection of epileptogenic zone as defined by intracranial EEG study results), which overall yielded good outcomes.

Outcomes of cingulate epilepsy surgery: insights from an institutional and patient-level systematic review and meta-analysis

OBJECTIVE

Due to their deep and medial location, range of seizure semiologies, and poor localization on ictal electroencephalography (EEG), cingulate gyrus seizures can be difficult to diagnose and treat. The aim of this study was to review the available evidence on postoperative outcomes after cingulate epilepsy surgery.

METHODS

A comprehensive literature search of the PubMed/MEDLINE, Ovid Embase, Ovid Scopus, and Cochrane Library databases was conducted to identify studies that investigated postoperative outcomes of patients with cingulate epilepsy. Seizure freedom at the last follow-up (at least 12 months) was the primary endpoint. The literature search was supplemented by the authors' institutional series (4 patients).

RESULTS

Twenty-one studies were identified, yielding a total of 105 patients (68 with lesional epilepsy [65%]). Median age at surgery was 23 years, and 56% of patients were male. Median epilepsy duration was 7.5 years. Invasive EEG recording was performed on 69% of patients (53% of patients with lesional epilepsy and 97% of those with nonlesional epilepsy, p < 0.001). The most commonly resected region was the anterior cingulate (55%), followed by the posterior (17%) and middle (14%) cingulate. Lesionectomy alone was performed in 9% of patients. Additional extracingulate treatment was performed in 54% of patients (53% of patients with lesional epilepsy vs 57% of those with nonlesional epilepsy, p = 0.87). The most common pathology was cortical dysplasia (54%), followed by low-grade neoplasm (29%) and gliosis (8%). Seizure freedom was noted in 72% of patients (median follow-up 24 months). A neurological deficit was noted in 27% of patients (24% had temporary deficit), with the most common deficit being motor weakness (13%) followed by supplementary motor area syndrome (9.5%). Univariate survival analysis revealed significantly greater probability of seizure freedom in patients with lesional epilepsy (p = 0.015, log-rank test).

CONCLUSIONS

Surgical treatment of drug-resistant focal epilepsy originating from the cingulate gyrus is safe, leads to low rates of permanent adverse effects, and leads to high rates of long-term seizure freedom in carefully selected patients. These data may serve as a benchmark for surgical counseling of patients with cingulate epilepsy.

Altered gray matter volume in MRI-negative focal to bilateral tonic-clonic seizures

To investigate cortical changes in MRI-negative patients with focal to bilateral tonic-clonic seizures (FBTCS). High-resolution three-dimensional T1-weighted MRI were collected with a GE 3.0-T MRI scanner from 26 patients with FBTCS and 21 healthy volunteers at Nanjing Brain Hospital. Voxel-based morphometry was performed on T1-weighted MRI of all subjects. A two-sample t test was performed to compare the GMV of two groups. Age and gender were taken as covariables, so that brain regions with significant differences, as compared by two-sample t test, between the two group were obtained. These regions were extracted as the regions of interest (ROIs) used for correlation analysis between ROIs and clinical variables. There is no significant difference in GMF between two groups. In FBTCS, regions with decreased GMV are bilateral thalamus, bilateral orbitofrontal cortex, left medical cingulate gyrus, and right supplementary motor area. GMV is increased within the bilateral para-hippocampal regions (voxel-wise FDR-corrected, P < 0.05). The GMVs are significantly negatively correlated with disease duration in the left thalamus and the left para-hippocampal region (P < 0.05). Seizures may lead to the loss of neurons and the decrease of GMV in FBTCS. The increase of GMV in some regions might be due to inflammatory responses in the early stages of epileptic seizures.

Cingulate gyrus epilepsy: semiology, invasive EEG, and surgical approaches

OBJECTIVE

The semiology of cingulate gyrus epilepsy is varied and may involve the paracentral area, the adjacent limbic system, and/or the orbitofrontal gyrus. Invasive electroencephalography (iEEG) recording is usually required for patients with deeply located epileptogenic foci. This paper reports on the authors' experiences in the diagnosis and surgical treatment of patients with focal epilepsy originating in the cingulate gyrus.

METHODS

Eighteen patients (median age 24 years, range 5-53 years) with a mean seizure history of 23 years (range 2-32 years) were analyzed retrospectively. The results of presurgical evaluation, surgical strategy, and postoperative pathology are reported, as well as follow-up concerning functional morbidity and seizures (median follow-up 7 years, range 2-12 years).

RESULTS

Patients with cingulate gyrus epilepsy presented with a variety of semiologies and scalp EEG patterns. Prior to ictal onset, 11 (61%) of the patients presented with aura. Initial ictal symptoms included limb posturing in 12 (67%), vocalization in 5, and hypermotor movement in 4. In most patients (n = 16, 89%), ictal EEG presented as widespread patterns with bilateral hemispheric origin, as well as muscle artifacts obscuring the onset of EEG during the ictal period in 11 patients. Among the 18 patients who underwent resection, the pathology revealed mild malformation of cortical development in 2, focal cortical dysplasia (FCD) Ib in 4, FCD IIa in 4, FCD IIb in 4, astrocytoma in 1, ganglioglioma in 1, and gliosis in 2. The seizure outcome after surgery was satisfactory: Engel class IA in 12 patients, IIB in 3, IIIA in 1, IIIB in 1, and IVB in 1 at the 2-year follow-up.

CONCLUSIONS

In this study, the authors exploited the improved access to the cingulate epileptogenic network made possible by the use of 3D electrodes implanted using stereoelectroencephalography methodology. Under iEEG recording and intraoperative neuromonitoring, epilepsy surgery on lesions in the cingulate gyrus can result in good outcomes in terms of seizure recurrence and the incidence of postoperative permanent deficits.

Cingulate gyrus epilepsy

The cingulate gyrus is located above the corpus callosum and forms part of the limbic system. Cingulate gyrus epilepsy poses a diagnostic challenge, given its diverse and variable seizure semiology. We present two patients with seizures arising in the cingulate gyrus that highlight the electroclinical and imaging features of this rare form of epilepsy. Cingulate seizures can give a wide range of clinical manifestations, which relate to the underlying neuroanatomy and subdivisions of the cingulate cortex. Here, we review the semiology of cingulate epilepsy and how this relates to the location of seizure onset and patterns of propagation.