Frontal lobe epilepsy

Abstract

We evaluated ictal 99mtechnetium hexamethyl propylene-amine-oxime single-photon emission computed tomography (SPECT) in 22 children with electroclinical features of frontal lobe epilepsy (FLE). Ictal SPECT demonstrated unilateral frontal hyperperfusion in 20 of 22 children (91%) (one lobar, two frontocentral, six dorsolateral, six frontopolar, three orbitofrontal, one medial frontal, and one insula), concordant with electroclinical lateralization in 19 of 20 (95%). Hyperperfusion was evident in the ipsilateral basal ganglia in 16 of 22 (73%) and the contralateral cerebellum in 14 of 22 children (64%). Interictal SPECT showed unilateral, localized frontal hypoperfusion concordant with electroclinical lateralization in only two of 22 children (9%). Ictal SPECT localization to the frontocentral, media frontal, or dorsolateral regions was associated with asymmetric tonic posturing, contralateral head/eye deviation, and unilateral clonic jerking (p < 0.01). Ictal SPECT localization to the frontopolar or orbitofrontal regions was associated with vocalization, hyperventilation, truncal flexion, and complex gestural automatisms (p > or = 0.05). Ictal SPECT has the potential to (1) localize seizures in patients with intractable FLE, and (2) advance understanding of the in vivo anatomico-clinical relationships of frontal lobe seizures.

Diffusion Tensor Imaging Assessment of the Epileptogenic Zone in Children with Localization-Related Epilepsy

“…36 The capability of DTI to localize the epileptogenic zone in suspected FLE is helpful because seizure lateralization can be difficult clinically and on EEG due to the rapid spread of seizure focus in FLE. 37,38 Of the 5 DTI indices, MD demonstrated greater lobar concordance and also greater overlap in all 3 x-, y-, and z-axes with the MEG dipole cluster in patients with MR imaging localization-related epilepsy, similar to the findings in previous studies in adults. [20][21][22] We have found DTI abnormalities occurring both within and also beyond the epileptogenic zone, similar to findings in previous studies.…”

The Clinical Use of SPECT in Focal Epilepsy

“…Although they may be very frequent, they are often brief, and simply too short to be captured by this method. They show a variety of ictal perfusion changes which are distinct from those seen in mesial temporal seizures, and apparently are consistent with the site of origin of the seizure within the frontal lobe, where this is known (23)(24)(25)(26)(27). Hyperperfusion of the basal ganglia, thalamus, and cerebellum seems to be common.…”

Disrupted Global and Regional Structural Networks and Subnetworks in Children with Localization-Related Epilepsy

“…Liu et al 30 also found that adult patients with left mesial TLE have significantly reduced regional efficiency in multiple regions in the temporal, frontal, and parietal lobes. We have found more regions of reduced nodal efficiency in the FLE than in the TLE subgroup, which may be due to the rapid spread of seizure activity as a result of the extensive network of connections of the frontal lobe and more frequent seizures in FLE [31][32][33] or, alternatively, an inherently more extensive abnormal regional efficiency from an underlying etiology that predispose to FLE. The more extensive impaired regional networks may be associated with poorer seizure-free surgical outcome in patients with FLE relative to those with TLE.…”

“…There were more subnetworks expressing reduced structural connectivity in FLE than in TLE, probably related to the rapid spread of seizure activity and more frequent seizures in FLE. [31][32][33] In both subgroups, the reduced structural connectivity predominantly involved the mesial temporal and frontal basal structures compared with controls. The spread of seizures from the frontal to temporal lobes in FLE and from the temporal to frontal lobes in TLE may have contributed to reduce structural connectivity between the frontal and temporal lobes.…”