Thermal ablation of bone lesions using Magnetic Resonance-guided (MRgFUS) Focused Ultrasound (GE-Insightec Exablate System)
Thermal ablation of deep tissues using focused ultrasound is a radiological procedure finalized in the ‘80s for the treatment of uterine fibroids. Recently this technique was fine-tuned and is also used in ablation of bone lesions, such as metastases and osteoid osteomas.
The source of ultrasound waves is formed by a focused transducer placed on the patient’s skin in correspondence of the deep lesion to treat. The cone-shaped ultrasound beam penetrates through soft tissues and concentrates in a specific target location generating for a few seconds a state of local hyperthermia (60-80°C) that determines irreversible necrosis of the treated tissue.
Thermal ablation treatment using magnetic resonance-guided focused ultrasound (GE-Insightec Exablate System) at high density field allows, without using ionising radiation, to plan treatment at its best, monitor it in real time (thermometry) and enable the physician to immediately assess the treatment outcome.
Treatment is usually performed in a single procedure. The patient is given local anaesthesia in the area to treat.
There are no specific contraindications except for those common to all interventional procedures and to the use of magnetic resonance systems (pacemaker, metal prostheses, metal stents etc).
Author: Ugo Albisinni MD, past Director of the structure of Radiology and diagnostic imaging.