Development of a Magnetic Resonance guided High Intensity Focused Ultrasound Therapy Platform for Perinatal Applications

先天性畸形是妊娠的并发症，可导致婴儿心力衰竭和流产。这些都是通过超声波诊断出来的，如果胎儿死亡的风险超过手术的风险，就可以进行治疗。目前的治疗方法都是微创进入子宫，有早产的风险。磁共振引导高强度聚焦超声（MRgHIFU）是一种无创治疗方法，在加拿大被临床批准用于子宫肌瘤和骨转移的热消融。MRgHIFU从位于患者下方的专用MRI台内的换能器传输超声能量，并将能量聚焦到体内，产生米粒大小的热损伤。这个焦点被引导到覆盖一个大的治疗量，而不需要重新定位病人。由于吸收的能量是非电离的和无切口的，感染的风险和长期副作用是最小的，使其成为胎儿干预的理想方式。然而，在批准的设备中，能量源位于不适合孕妇的配置中，这不适合安全和符合人体工程学的可行治疗。该项目的目标是开发一种新的模块化MRgHIFU机器人平台，将HIFU传感器带到MRI扫描仪内的患者身上，为我们一些最脆弱的儿科患者提供一种新颖、安全和无创的治疗技术。

Congenital abnormalities are complications of pregnancy that can lead to heart failure of the baby and loss of pregnancy. These are diagnosed by ultrasound and can be treated if the risk of fetal death outweighs the risk of surgery. Current therapies all involve minimally invasive access into the uterus and comes with a risk of preterm birth. Magnetic resonance guidedhigh intensity focused ultrasound (MRgHIFU) is a noninvasive therapy that is clinically approved in Canada for thermal ablation of uterine fibroids, and bone metastasis. MRgHIFU transmits ultrasound energy from a transducer located inside a dedicated MRI table that is below the patient, and focuses that energy into the body, producing a thermal lesion as small as a rice kernel. This focus is steered to cover a large treatment volume without repositioning the patient. Since the absorbed energy is nonionizing and incisionless, the risk of infection and long-term side effects are minimal, making it an ideal modality for fetal interventions. However, in the approved devices the energy source is located in configurations that are notadapted for a pregnant mother, and this is not amenable to a safe and ergonomically feasible treatment. The objective of this project is to develop a new modular MRgHIFU robotic platform that brings a HIFU transducer to a patient inside an MRI scanner in a configuration that provides a novel, safe and noninvasive therapy technology for some of our mostvulnerable pediatric patients.