Early implementation of stereoelectroencephalography in children: a multiinstitutional case series

OBJECTIVE

Pediatric stereoelectroencephalography (SEEG) has been increasingly performed in the United States, with published literature being limited primarily to large single-center case series. The purpose of this study was to evaluate the experience of pediatric epilepsy centers, where the technique has been adopted in the last several years, via a multicenter case series studying patient demographics, outcomes, and complications.

METHODS

A retrospective cohort methodology was used based on the STROBE criteria. ANOVA was used to evaluate for significant differences between the means of continuous variables among centers. Dichotomous outcomes were assessed between centers using a univariate and multivariate logistic regression.

RESULTS

A total of 170 SEEG insertion procedures were included in the study from 6 different level 4 pediatric epilepsy centers. The mean patient age at time of SEEG insertion was 12.3 ± 4.7 years. There was no significant difference between the mean age at the time of SEEG insertion between centers (p = 0.3). The mean number of SEEG trajectories per patient was 11.3 ± 3.6, with significant variation between centers (p < 0.001). Epileptogenic loci were identified in 84.7% of cases (144/170). Patients in 140 cases (140/170, 82.4%) underwent a follow-up surgical intervention, with 47.1% (66/140) being seizure free at a mean follow-up of 30.6 months. An overall postoperative hemorrhage rate of 5.3% (9/170) was noted, with patients in 4 of these cases (4/170, 2.4%) experiencing a symptomatic hemorrhage and patients in 3 of these cases (3/170, 1.8%) requiring operative evacuation of the hemorrhage. There were no mortalities or long-term complications.

CONCLUSIONS

As the first multicenter case series in pediatric SEEG, this study has aided in establishing normative practice patterns in the application of a novel surgical technique, provided a framework for anticipated outcomes that is generalizable and useful for patient selection, and allowed for discussion of what is an acceptable complication rate relative to the experiences of multiple institutions.

Functional hemispherectomy: can preoperative imaging predict outcome?

OBJECTIVE

Although hemispherectomy is an effective treatment for children with intractable hemispheric epilepsy syndromes, as many as 40% of patients eventually develop seizure recurrence. The causes of seizure recurrence in these patients are incompletely understood. The authors sought to evaluate the efficacy of hemispherectomy at their center and determine whether contralateral MRI abnormalities can predict seizure recurrence.

METHODS

A retrospective review of consecutive hemispherectomies performed at Miami Children's Hospital between January 2000 and June 2014 was performed. Time-to-event analysis was performed. The "event" was defined as any seizures following resective epilepsy surgery (not including seizures in the first postoperative week and auras). Several preoperative variables were analyzed to determine their suitability to predict seizure recurrence following surgery.

RESULTS

Sixty-nine patients (44 boys) with a mean age of 8.2 ± 5.9 years (range 0.1-20.8 years) underwent 72 hemispherectomies; 67 of these were functional hemispherectomies, while another 5 were completion of a previous functional hemispherectomy (2 completions of functional hemispherectomies, 3 anatomical hemispherectomies). The duration of epilepsy was 5.8 ± 5.5 years with 66 cases (91.7%) having daily seizures. Etiology included stroke (n = 28), malformation of cortical development (n = 11), hemimegalencephaly (n = 11), encephalitis (n = 13), and other (n = 7). Engel class I outcome was achieved in 59 (86%) and 56 (81%) patients at 1 and 2 years of follow-up, respectively. The mean time to seizure recurrence was 33.5 ± 31.1 months. In univariate analyses, the absence of contralateral abnormalities on MRI (HR 4.09, 95% CI 1.41-11.89, p = 0.009) was associated with a longer duration of seizure freedom. The presence of contralateral MRI abnormalities was associated with contralateral ictal seizures on preoperative scalp EEG (p = 0.002). Fifteen patients experienced 20 complications (20/72, 27.8%), including the development of hydrocephalus necessitating CSF diversion in 9 cases (13%), hygroma in 1, hemispheric edema in 1, aseptic meningitis in 2, postoperative hemorrhage in 2, infection in 2, ischemic stroke in 2, and blood transfusion-contracted hepatitis C in 1 case.

CONCLUSIONS

Patients with bihemispheric abnormalities, as evidenced by contralateral MRI abnormalities, have a higher risk of earlier seizure recurrence following functional hemispherectomy.

ABBREVIATIONS

EVD = external ventricular drain; MCD = malformation of cortical development; MEG = magnetoencephalography; PVWM = periventricular white matter; TTE = time-to-event; VPS = ventriculoperitoneal shunt.

Management Strategies for Intracranial Pressure Crises in Subarachnoid Hemorrhage

Objectives: Standard management strategies for lowering intracranial pressure (ICP) in traumatic brain injury has been well-studied, but the use of lesser known interventions for ICP in subarachnoid hemorrhage (SAH) remains elusive. Searches were performed in PubMed and EBSCO Host to identify best available evidence for evaluation and management of medically refractory ICP in SAH. The role of standard management strategies such as head elevation, hyperventilation, mannitol and hypertonic saline as well as lesser known management such as sodium bicarbonate, indomethacin, tromethamine, decompressive craniectomy, decompressive laparotomy, hypothermia, and barbiturate coma are reviewed. We also included dose concentrations, dose frequency, infusion volume, and infusion rate for these lesser known strategies. Nonetheless, there is still a gap in the evidence to recommend optimal dosing, timing and its role in the improvement of outcomes but early diagnosis and appropriate management reduce adverse outcomes.