MRIguided

MRI-guided, or MRI-guided intervention, refers to medical procedures that use magnetic resonance imaging (MRI) to plan, guide, and monitor interventions in real time or near real time. MRI provides high-contrast images of soft tissues without ionizing radiation, enabling precise targeting and continuous assessment during therapy.

In MR-guided procedures, the patient is positioned in an MRI suite with MR-compatible instruments and devices. Real-time imaging sequences, along with image fusion and navigation software, allow clinicians to visualize target lesions and surrounding anatomy as needles, probes, or therapeutic devices are advanced. Some systems integrate interventional suites with robotic or hydraulic positioning to improve stability.

Common applications include MR-guided biopsy (breast, prostate, liver) where sampling is directed by MR images; MR-guided focused ultrasound (MRgFUS), used for neurological conditions like essential tremor and for uterine fibroids; and MR-guided radiotherapy (MRgRT) or adaptive radiotherapy, where treatment plans are adjusted based on daily MRI.

Benefits include improved targeting accuracy, reduced radiation exposure to non-target tissues in radiotherapy, and the ability to visualize soft tissue changes during therapy. Limitations include higher equipment costs, need for MR-compatible tools, longer procedure times, potential discomfort for patients, and safety considerations related to strong magnetic fields and heating. The MR environment also requires careful management of contrast agents.

Research and clinical use continue to expand, with development of real-time diffusion or functional MRI, and integrated MRI-guided robotic systems. MR-guided techniques are offered in specialized centers and are subject to regulatory approvals and institutional protocols.