Outcomes of resective surgery in pediatric patients with drug-resistant epilepsy: A single-center study from the Eastern Mediterranean Region.

OBJECTIVE: Epilepsy surgery is widely accepted as an effective therapeutic option for carefully selected patients with drug-resistant epilepsy (DRE). There is limited data on the outcome of epilepsy surgery, especially in pediatric patients from the Eastern Mediterranean region. Hence, we performed a retrospective study examining the outcomes of resective surgery in 53 pediatric patients with focal DRE. METHODS: Patients with focal DRE who had undergone epilepsy surgery were included in the present study. All patients underwent a comprehensive presurgical evaluation. Postoperative seizure outcomes were classified using the Engel Epilepsy Surgery Outcome Scale. RESULTS: After surgery, 33 patients (62.2%) were Class I according to the Engel classification of surgical outcomes; eight patients (15.0%) were Class II, 11 (20.7%) were Class III, and one (1.8%) was Class IV. The relationships of presurgical, surgical, and postsurgical clinical variables to seizure outcomes were compared. Older age at seizure onset, older age at the time of surgery, the presence of focal to bilateral tonic-clonic seizures, seizure duration over 2 minutes, unsuccessful treatment with three or fewer antiseizure medications, lesions confined to one lobe (as demonstrated via magnetic resonance imaging [MRI]), surgical site in the temporal lobe, and histopathology including developmental tumors were significantly linked to an Engel Class I outcome. A univariate analysis of excellent surgical outcomes showed that lateralized semiology, localized interictal and ictal electroencephalogram (EEG) discharges, lateralized single-photon emission computed tomography and positron emission tomography findings, and temporal lobe resections were significantly related to excellent seizure outcomes. SIGNIFICANCE: The results of our study are encouraging and similar to those found in other centers around the world. Epilepsy surgery remains an underutilized treatment for children with DRE and should be offered early.

Posterior fossa extra-axial variations of medulloblastoma: a pictorial review as a primer for radiologists.

Manifestations of an atypical variant of medulloblastoma of the posterior fossa in extra-axial locations have been reported, and key questions concerning its interpretation have been raised previously. This review illustrated the clinico-radiological and histopathological features of the posterior fossa extra-axial medulloblastoma and described possible management strategies. We thoroughly reviewed all atypical anatomical locations of medulloblastoma reported within the posterior fossa and extra-axial spaces. The main characteristics of diagnostic imaging and histopathological results, primarily the distinctive radiopathological characteristics, were summarized to distinguish between intra- and extra-axial medulloblastoma, or pathologies mimicking this tumor. Most cases of posterior fossa extra-axial medulloblastoma have been reported in the cerebellopontine angle, followed by the tentorial and lateral cerebellar locations. The dural tail sign, which is commonly observed in meningioma, is rarely seen in intra- or extra-axial medulloblastoma and might be associated with other benign or malignant lesions. In addition to magnetic resonance imaging, the proposed new imaging techniques, including advances in modern neuroimaging modalities, were discussed, as potentially efficient modalities for characterizing extra-axial medulloblastoma. Radionuclide imaging and magnetic resonance perfusion imaging are practical alternatives to limit the number of differential diagnoses. We believe that medulloblastoma cases are likely under-reported because of publication bias and frequent tumors in unusual locations. Addressing these issues would help establish a more accurate understanding of this entity.

Utility of single-photon emission computed tomography (SPECT) in presurgical evaluation of children: A single-center experience.

OBJECTIVE: Single-photon emission computed tomography (SPECT) is an ancillary noninvasive test commonly used to identify the epileptogenic zone. However, its proper utilization may be limited depending on the resources available at each center. This study aimed to investigate the utility of SPECT in presurgical evaluation of children at our center. METHODS: This was an observational retrospective study in 150 children who were admitted to the Epilepsy Monitoring Unit for presurgical evaluation between 2012 and 2019. The utility of interictal and ictal SPECT in different clinical cohorts was analyzed. RESULTS: Only interictal SPECT was performed on 87 patients (58 %), while ictal SPECT was performed on 62 (41.3 %), and interictal SPECT alone was considered of low diagnostic value. Ictal SPECT was unremarkable in 27 of 62 patients and abnormal in 35. Ictal SPECT was localized to the temporal lobe in 62.8 % and to the extratemporal lobe in 25.7 % of the patients and lateralized to one hemisphere in 11.4 % of the patients. In the abnormal SPECT group, ictal SPECT was considered unnecessary in 7/35 (20 %) patients with a single lesion and 3/35 (8.5 %) patients with a hemispheric lesion. In the remaining 25 patients, surgery was recommended more frequently than invasive EEG monitoring (IEM) for diffuse lesion cases (P = 0.03), while IEM was recommended more frequently than surgery for MRI-negative cases (P = 0.03), and in this group none of the MRI-negative patients underwent surgery. In our entire cohort, epilepsy surgery was performed on 24.4 % of the patients, 64 % with a single lesion, 7.6 % with a hemispheric lesion, 25.6 % with a diffuse lesion, and only one MRI-negative patient (2.5 %). Surgery was performed in 48.7 % of single lesion cases and 20.5 % of diffuse lesion cases with either unremarkable or no ictal SPECT. Engel class I outcome was achieved in 62 % and class II outcome in 33 % of the patients. In the single lesion etiology, 72 % (18/25) patients achieved excellent outcome and within this group, 22 % (4/18) patients had a positive ictal SPECT whereas 78 % (14/18) patients either did not get an ictal SPECT or it was unremarkable. SIGNIFICANCE: Based on our findings, we suggest carefully selecting patients for SPECT imaging to improve its utility and prevent overutilization and potential harm to children.