Magnetic Resonance-Guided Laser Interstitial Thermal Therapy: Historical Perspectives and Overview of the Principles of LITT

Abstract

Over the past 5 years, laser interstitial thermal therapy (LITT) has become a well-recognized and viable addition to the armamentarium of neurosurgeons when considering patient options for brain tumors and epilepsy. In addition, patients are actively seeking such alternative minimally invasive techniques when the prospect of open craniotomy is presented to them. As such, it is important that the fundamentals of LITT are well documented for both physicians and patients. This chapter provides a historical perspective of laser interstitial thermal therapy (LITT), including the fundamental science and contributing technologies including laser, laser-tissue interactions, imaging and thermal dosimetry, cellular effects of LITT and their relation to MR image appearance post-LITT, and clinical applications in brain lesions. The second half of the chapter is devoted to a description that compares and contrasts the two existing commercially available LITT systems, namely NeuroBlate® and Visualase®. In addition, included in this unique perspective are detailed approaches to clinical implementation, trajectory guidance, laser energy delivery probes, user interface and software systems, process workflow, integration with MRI systems, and specifics of thermal calculations for clinical monitoring.