TRANS-CRANIAL MRI-GUIDED FOCUSED ULTRASOUND SURGERY (TCMRGFUS): PRELIMINARY ITALIAN (AND WORLD-FIRST) EXPERIENCE AT 1,5 TESLA (first 3 cases treated)

Abstract

PURPOSE: We present our preliminary results achieved with the first Italian installation of a trans-cranial MRI-guided Focused Ultrasound Surgery (tcMRgFUS) certified system for functional neurosurgery. Moreover, to our knowledge, this is the world-first tcMRgFUS system ever installed on a 1.5T MRI unit. TcMRgFUS is a promising new technology for the non-invasive treatment of neurologic disorders such as Essential Tremor (ET), tremor dominant idiopathic Parkinson's Disease (PD) and Neuropathic Pain (NP). This is a new method for focal targeting and lesioning of specific regions in the brain through intact skull by using high intensity focused ultrasound beam to achieve thermal ablation and MR imaging system for the anatomic visualization, a correct treatment planning and real-time thermometry. METHOD AND MATERIALS: Patient enrolment was based on indication for functional neurosurgery and evidence of medication-refractory disease; a detailed medical history has been collected together with a complete clinical examination and a neurophysiological assessment. Eligible patients were screened by MDCT and MRI. Patients were monitored according to Standards for Basic Anesthetic Monitoring. Patients were sedated with midazolam and continuous infusion of remifentanil aiming to reach a sedation level of Wilson Sedation Score 2-3 (drowsy – eyes closed but rousable to command). TcMRgFUS treatments were performed by a neurosurgeon with proven experience in functional neurosurgery, and an experienced neuroradiologist, optimizing treatment parameters case by case. RESULTS: Although this is a preliminary experience, the clinical success of our first treatments proves that this promising new technology for non-invasive treatment of various brain disorders can be safety and effectively performed also with the most popular MRI units operating at 1.5T. Treated patients had no complications at all, with almost immediate significant clinical benefit. CONCLUSION AND DISCUSSION: TcMRgFUS treatments are currently performed in very few centers throughout the world and only using 3T MRI units. This is the world-first experience of functional neurosurgery successfully performed with a tcMRgFUS installed on the most popular and affordable 1.5T MR units. Direct translational impacts are expected by the use of widely installed 1.5T MRI units both on patient quality of life and to decrease health care costs, with inherent reduction in drug use and needs for medical examination. Being able to use a radiation-free technique like the MRI as a guide and, even further, being able to verify the clinical effectiveness of such an innovative treatment before a permanent lesion is made in the targeted area of the brain is a huge step forward for both interventional radiology and functional neurosurgery.