MRI ( Magnetic Resonance Imaging) is a powerful imaging modality used for diagnosis, staging, treatment planning, and follow-up of various cancers.
Principle: Uses strong magnetic fields and radiofrequency pulses to produce detailed images of soft tissues without ionizing radiation.
Advantages: Superior soft tissue contrast resolution compared to CT or X-ray.
- Multiplanar imaging (axial, sagittal, coronal).
- Functional imaging capabilities (diffusion-weighted imaging, perfusion imaging).
- No radiation exposure, safe for repeated use.
- Common Oncology Uses:
- Brain tumors: diagnosis, surgical planning, monitoring response.
- Breast cancer: screening high-risk patients, assessing extent of disease.
- Prostate cancer: detection and staging.
- Soft tissue sarcomas: characterization and staging.
- Liver tumors: characterization and detection of metastases.
- Head and neck cancers: detailed local staging.
- Limitations:
- Longer scan times than CT.
- More expensive and less available than some other modalities.
- Contraindications: pacemakers, certain metal implants.
- Claustrophobia can limit patient tolerance.
- Contrast Agents: Gadolinium-based agents enhance tumor visualization but require caution in renal impairment (risk of nephrogenic systemic fibrosis).
Synonyms
MRI