Introduction: Laser-induced thermal therapy (LITT) is an emerging technology for the treatment of intracranial pathologies. LITT uses laser energy delivered through a fiberoptic catheter inserted into the lesion through a 3 mm cranial opening; the ablation is performed under MRI guidance. However, the literature on the use of LITT in pediatric intracranial neoplasms is limited.

Methods: We present here, our initial experience with the use of LITT in a series of 3 pediatric patients with intracranial tumors. Patients were selected for laser therapy if conventional open craniotomies were deemed to have unacceptably high risks. Surgical technique: Patients’ had pre-operative MRI performed on the day of surgery for stereotactic navigation, followed by placement of the Leksell frame. Laser probe was then placed through a 3 mm cranial opening with the tip inside the lesion using the Leksell frame co-ordinates as determined from the pre-operative MRI scan. The lesion was then ablated with the laser probe under real-time MRI guidance with re-positioning the probe tip as required. Post-operative and short-term follow-up outcomes are presented.

Results: We treated 3 patients with intracranial tumors (SEGA, thalamic glioma, thalamic ependymoma) between February 2012 - January 2013. Age of the patients ranged from 6 to 18 years. Patients stayed an average of 2.6 days after procedure. No intra-operative or post-operative complications were noted. Follow-up ranged from 2 to 14 months with the average post-operative follow-up duration of 7.3 months. On follow-up imaging, all patients had a decrease in tumor size.

Conclusions: LITT under MRI guidance appears both technically feasible and clinically safe to treat a variety of intracranial neoplasms. Post-operative and short-term follow-up outcomes are promising. Larger series and long-term outcomes are needed to better define the indications and demonstrate the efficacy of this emerging technology.

Patient Care: Present the less invasive and technically feasible treatment option for difficult-to-treat pediatric intracranial neoplasms which are often considered inoperable due to high risk of surgical morbidities with the conventional surgical treatment. Our experience with the surgical procedure and the technical details of the procedure will be discussed.

Learning Objectives: 1. Present the surgical technique and technical details during the laser treatment of difficult intracranial neoplasms with MRI guidance. 2. Present the post-operative and short term outcomes after laser treatment of pediatric intracranial neoplasms.

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