Minimally Invasive MR Imaging–Guided Stereotactic Laser Thermal Ablation in Neurosurgical Cases of Pediatric Lesional Epilepsy: A Didactic Step-by-Step Practical Approach

L.S. Medina, E. Alvarado, E. Pacheco, N. Altman, O. Villegas, I. Medina, C. Medina, J. Ragheb, and S. Bhatia

View Article on Neurographics Website

Date of Activity Release: Dec. 1, 2016
Date of Activity Expiration: Dec. 1, 2019

Target Audience:
Intended for neuroradiologists and neuroradiology trainees with varying degrees of experience.

Learning Objectives:
Understand and describe the benefits of the step-by-step approach for minimally invasive MR imaging–guided stereotactic laser thermal ablation in selected patients with epilepsy.

MR imaging–guided thermal ablation, an alternative to conventional surgery, is a minimally invasive procedure with a decrease in the hospital length of stay and intensive care unit use. This procedure, with converging imaging, clinical, and videotelemetry data, has had early success in selected pediatric neurosurgical patients with intractable epilepsy. Our purpose was to describe the step-by-step approach used in our institution for minimally invasive MR imaging–guided stereotactic laser thermal ablation, along with some of its benefits. Use of fast single-shot T1- and T2-weighted sequences allows a rapid outline of the catheter position, which is followed by a targeted limited higherresolution T2-weighted sequence for detailed assessment of the lesion margins and adjacent critical structures. In our experience, diffusion-weighted images and T2- weighted images allow fast assessment of the treatment effect and correlate well with the real-time estimate of cell death and posttreatment area of encephalomalacia. We found that contrast imaging did not change the treatment plan or outcome. Therefore, we adopted a tailored fast thermal ablation treatment imaging protocol that relied on short and fast acquisitions, including DWI and single-shot T1- and T2-weighted sequences, and allowed a decrease in imaging acquisition time to approximately 45 to 60 minutes and allowed the addition of these patients to the regular MR imaging schedule without major disruptions to overall patient flow. This new approach allowed the spectrum of surgical intervention in intractable epilepsy to include MR imaging–guided thermal ablation as a prephase I or II alternative. A detailed procedure description was provided, followed by examples of patients we treated.

Commercial Support
No commercial support was received for this activity.

Credit Designation Statement

The American Society of Neuroradiology is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

The American Society of Neuroradiology designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit(s)TM. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Method of Physician Participation:
Each participant will review the corresponding Neurographics article located at Upon completion, each physician will complete and pass a post-test with a score of at least 80% to receive a CME certificate.

All individuals in control of content have disclosed the following relevant financial relationships. All of these relationships were treated as a conflict of interest, and have been resolved (C7 SCS 6.1-6.2, 6.5)

Authors have no relevant financial relationships.





Barton Branstetter 

Editor in Chief

None, N/A

Adam Flanders

Deputy Editor

Royalties, Lippincott Williams and Wilkins

Robert Quencer 

Consulting Editor

None, N/A

Mark Mullins

Associate Editor

Non-remunerative position, AUR6

Meng Law

Associate Editor

Stockholder, Clinical Imaging

Michele Johnson

Associate Editor

Consultant, Boston Scientific, Inc.

Edward Escott

Associate Editor

Grant, Atherysys, Inc.; Royalties, Thieme Medical Publishers

Scott Faro

Associate Editor

None, N/A

Tina Young Poussaint

Associate Editor

None, N/A

Dheeraj Ghandi

Associate Editor

Grant, Arstasis, Axera Inc.; Consultant, Covidien, EV3

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