MAGNETIC RESONANCE IMAGING (MRI)

• Imaging modality utilizing the magnetic property of the nuclei

• Study of the response of magnetized tissue to a pulse of radiofrequency whereby pathological tissue returns different signals as compared to normal tissues

Uses of MRI

1. Imaging modality of choice for study of the brain & spinal cord

2. Musculoskeletal (MSK) o Accurate imaging for joints, ligaments and muscles

3. Cardiac imaging related to the cardiac cycle

4. Assessment of mediastinalvascular structures (-) CM

5. Abdominal imaging with better visualization of each organ aided by presence of FAT

6. Pelvic imaging

• neoplasm (tumors) in males & females

• Male – prostate gland and urinary bladder

• Female – uterus, ovaries, fallopian tube, and urinary bladder

Advantages of MRI

1. Multiplanar imaging – All the planes (axial, coronal, parasagittal, sagittal)

2. No ionizing radiation

3. Excellent anatomical detail (presentation of an organ)

4. (-) bone artifacts

5. Visualization of blood vessels without introduction of contrast material

6. Contrast material is less frequently used than in CT

Disadvantages of MRI

1. High operation cost

2. Longer examination time – main disadvantage

3. Poor images for lungs

4. Inability to show calcification with accuracy

5. Acute hemorrhages or bleeding not as well-visualized as in CT

6. Contraindications in patients with devices that are affected by magnets

Scientists

1. FELIX BLOCH withEDWARD PURCELL o Both discovered Nuclear Magnetic Resonance (NMR) Spectroscopy

2. RAYMOND DAMADIAN o Reported the differences in NMR images/parameters between normal tissues &abnormal tissues/tumors

3. PAUL LAUTERBUR o Publicized the 1st NMR image