Subcentimeter epilepsy surgery targets by resting state functional magnetic resonance imaging can improve outcomes in hypothalamic hamartoma

Abstract

Objective: The purpose of this study is to investigate the outcomes of epilepsy surgery targeting the subcentimeter-sized resting state functional magnetic resonance imaging (rs-fMRI) epileptogenic onset zone (EZ) in hypothalamic hamartoma (HH). Methods: Fifty-one children with HH-related intractable epilepsy received anatomical MRI-guided stereotactic laser ablation (SLA) procedures. Fifteen of these children were control subjects (CS) not guided by rs-fMRI. Thirty-six had been preoperatively guided by rs-fMRI (RS) to determine EZs, which were subsequently targeted by SLA. The primary outcome measure for the study was a predetermined goal of 30% reduction in seizure frequency and improvement in class I Engel outcomes 1 year postoperatively. Quantitative and qualitative volumetric analyses of total HH and ablated tissue were also assessed. Results: In the RS group, the EZ target within the HH was ablated with high accuracy (>87.5% of target ablated in 83% of subjects). There was no difference between the groups in percentage of ablated hamartoma volume (P = 0.137). Overall seizure reduction was higher in the rs-fMRI group: 85% RS versus 49% CS (P = 0.0006, adjusted). The Engel Epilepsy Surgery Outcome Scale demonstrated significant differences in those with freedom from disabling seizures (class I), 92% RS versus 47% CS, a 45% improvement (P = 0.001). Compared to prior studies, there was improvement in class I outcomes (92% vs 76%-81%). No postoperative morbidity or mortality occurred. Significance: For the first time, surgical SLA targeting of subcentimeter-sized EZs, located by rs-fMRI, guided surgery for intractable epilepsy. Our outcomes demonstrated the highest seizure freedom rate without surgical complications and are a significant improvement over prior reports. The approach improved freedom ---

Network‐targeted approach and postoperative resting‐state functional magnetic resonance imaging are associated with seizure outcome

“…Those patients with a hypothalamic hamartoma received a secondary analysis described in detail in Boerwinkle et al The ICA results were used to filter out noise, and a seed analysis (searchlight analysis [V.L.B.]) within the hamartoma was performed both before and after surgery . The preoperative rs‐fMRI was registered to the postoperative image anatomical MRI for visual inspection.…”

“…Those patients with a hypothalamic hamartoma received a secondary analysis described in detail in Boerwinkle et al 29 The ICA results were used to filter out noise, and a seed analysis (searchlight analysis [V.L.B.]) And, barring anatomical differences created from surgery, residual detected spatial pattern matching expected RSNs for spatial location.…”

“…within the hamartoma was performed both before and after surgery. 29 The preoperative rs-fMRI was registered to the postoperative image anatomical MRI for visual inspection. The postoperative seed was placed over the entire hamartoma and the entire region was reanalyzed, voxel-by-voxel, for connectivity from the HH to the rest of the brain grey matter.…”

One-Stage High-Density Focal Stereo-Array SEEG-Guided Radiofrequency Thermocoagulation for the Treatment of Pediatric Giant Hypothalamic Hamartomas

“…Most of the electrodes designed for disconnecting the attachment of the HHs are located near the interface. Due to the small sample size, we have not been able to determine the subcentimeter targets for ablation like that in fMRI ( 37 ). There was no difference of epileptic activity between the electrodes near the interface and those in deeper area.…”

Letter to the Editor. Resting-state functional MRI for functional neurosurgery: seeing the light?

“…Boerwinkle et al 1 have recently suggested that using rs-fMRI might improve outcomes using MRI-guided stereotactic laser ablation for hypothalamic hamartomas. We have demonstrated before how stereotactic radiosurgical thalamotomy for drug-resistant essential tremor (ET) correlates with changes within large-scale brain networks ( Figure 1) [6][7][8][9][10] .…”