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Erschienen in: Child's Nervous System 3/2019

09.01.2019 | Original Article

Magnetic resonance-guided laser interstitial thermal therapy for the treatment of non-lesional insular epilepsy in pediatric patients: thermal dynamic and volumetric factors influencing seizure outcomes

verfasst von: Hepzibha Alexander, Kelsey Cobourn, Islam Fayed, Dewi Depositario-Cabacar, Robert F. Keating, William D. Gaillard, Chima O. Oluigbo

Erschienen in: Child's Nervous System | Ausgabe 3/2019

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Abstract

Purpose

To investigate the safety and efficacy of stereoelectroencephalography (sEEG) directed magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) in medically refractory insular epilepsy in pediatric patients, define the relationship between ablation volumes and seizure control, and analyze the relationship between thermal energy and ablation volumes.

Methods

A single-institution, retrospective review of pediatric patients with insular epilepsy who underwent sEEG directed MRgLITT over a 10-month period was performed. Perioperative, imaging, and outcome data were analyzed. Seizure outcomes were determined based on Engel score (Engel I versus Engel II–IV). Insula and ablation volumes were measured, and the proportion of insula volume ablated was calculated. Thermal energy was calculated in joules.

Results

Four patients underwent sEEG directed MRgLITT of insular epileptogenic foci. The ablation volume was higher in patients with Engel I outcome (3.93 cm3) compared to Engel II–IV outcome (1.02 cm3). The proportion of ablation to insula volume was lowest in patients with Engel II–IV outcome (25.09%). The mean energy requirement to create a unit volume of ablation in the insula is 1205.86 J. A linear trend was noted between thermal ablation energy and ablation volume (R2 = 0.884). Over a mean follow-up period of 104 days, three patients were seizure-free (Engel I), and one patient saw significant improvement in seizure frequency (Engel III).

Conclusions

The proportion of insula ablated, as well as the volume of ablation, are related to seizure outcome with increasing ablation volumes corresponding to improved seizure control. Further analysis of insula laser ablation thermal dynamics and volumes is needed.
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Metadaten
Titel
Magnetic resonance-guided laser interstitial thermal therapy for the treatment of non-lesional insular epilepsy in pediatric patients: thermal dynamic and volumetric factors influencing seizure outcomes
verfasst von
Hepzibha Alexander
Kelsey Cobourn
Islam Fayed
Dewi Depositario-Cabacar
Robert F. Keating
William D. Gaillard
Chima O. Oluigbo
Publikationsdatum
09.01.2019
Verlag
Springer Berlin Heidelberg
Erschienen in
Child's Nervous System / Ausgabe 3/2019
Print ISSN: 0256-7040
Elektronische ISSN: 1433-0350
DOI
https://doi.org/10.1007/s00381-019-04051-0

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