Development of an MRI-Compatible Device for Prostate Focal Therapy

We present a device that has been developed for delivering prostate focal thermal therapy under magnetic resonance imaging (MRI) guidance. Unlike most existing devices, ours is capable of delivering needles to targets in the prostate without removing the patient from the scanner. This feature greatly reduces procedure time and increases accuracy. The device consists of a mechanical linkage encoded with optical incremental encoders, and is manually actuated. A custom magnetic resonance (MR) compatible alignment interface allows the user to manually align the device to its target with high accuracy in-bore in very short time. The use of manual actuation over motors greatly reduces the complexity and bulk of the system, making it much more compact and portable. This is important when dealing with such tight space constraints. Needle targeting experiments in gel phantoms have demonstrated the device's ability to deliver needles with an accuracy of 2.1 +/- 1.3 mm.