1. Magnetic Resonance Imaging MRI

2. MRI Becoming the imaging method of choice in small animal medicine
Superior, high-contrast anatomically detailed images of soft tissue
Non-invasive
Multiple image planes

3. MRI Radiography and CT use x-rays MRI uses
electromagnetic signal emitted from protons in different tissues

4. How does it work? Complex Manipulates the energy state of protons
Powerful magnet

5. How does it work? Radiofrequency pulse applied
Allowed to return to original state

6. How does it work? Relaxation Receiver coil detects signal
Occurs at different rates in different tissues
Leads to the release of energy
Signal
Receiver coil detects signal
Computer displays signal data as image
Shade of grey assigned based on difference
Contrast media
Further differentiate tissues

7. Contrast Media Gadolinium
Areas that retain agent appear lighter on final image

8. MRI Advantages Primarily a diagnostic tool
Can help locate neoplasm for excision or irradiation
Used when traditional diagnostic imaging cannot work – as in CNS
Comparable to CT in results obtained

9. MRI Disadvantages Cost Sedation/General anesthesia use
Transport of patient
Lack of facilities
Becoming more prevalent

10. MRI Disadvantages Safety Microchips Pacemakers
Magnetic metals –bbs, bullets, metal shaving (eye)
Nothing in room that is metal
Equipment certified MRI safe

11. MRI Indications for use CNS disorders
Seizures, ataxia, cranial nerve abnormalities, paresis, paralysis

12. MRI Indications for use Neoplasms Inflammatory Conditions
Hemorrhage and Infarction
Seizures
Spinal Cord and Vertebral Column Disorders
Nasal Tumors
Eye and orbital disease
Musculoskelatal Conditions
Vascular abnormalities
Bulla disorders