Focused Ultrasound in Pediatric Neuro-Oncology: Current Applications and Future Directions

Focused ultrasound (FUS) is a minimally invasive procedure with recent applications to patients with neurosurgical conditions. To date, most neuro-oncologic applications of FUS have occurred in the adult population to target high-grade gliomas and brain metastases. Its potential applications in pediatric neuro-oncology are only just starting to be realized. In children, high intensity focused ultrasound (HIFU) has been used to treat benign intracranial lesions such as hypothalamic hamartoms and subependymal giant cell astrocytomas. Experience is now accruing with the use of low intensity focused ultrasound (LIFU) in conjunction with systemically administered microbubbles in children to disrupt the blood brain barrier (BBB) using magnetic resonance-guided focused ultrasound (MRgFUS). The pediatric brain tumor for which this application has been used is diffuse intrinsic pontine glioma (DIPG), a typically fatal neoplasm in children ages 5 – 7 years. Here, the history of FUS is reviewed, the principles of FUS therapy are delineated, and a discussion of its applications in neuro-oncology with a focus on pediatric neuro-oncology is provided. Innovations in MRgFUS are ushering a new and exciting era of minimally invasive treatments for children with brain tumors.