Contrast is widely used in body MRI, but is it always necessary? This presentation will review clinical scenarios and protocols where contrast may not be required.
· Contrast is commonly used in many body MR studies, but safety and cost are considerations
· Understanding how best to deploy the sequences at our disposal is important
· Clinical scenarios will be presented with suggested protocols where contrast may not be necessary
1. To understand the pros and cons of contrast in body MRI
2. To review application of commonly used sequences in body MRI
3. To review clinical scenarios and protocols where contrast may not be necessary or should not be used
Contrast is widely used in body imaging, but is it always necessary? This presentation will briefly discuss some of the concerns that are associated with contrast agents. Although greater awareness and appropriate use of more stable agents has largely removed the spectre of Nephrogenic Systemic Fibrosis, other risks remain. These include general risks of any contrast agent, including allergy and puncture site complications. A recently discovered more specific risk with unknown long-term implications is tissue deposition of contrast.
Clinical application of commonly used sequences in body MRI will be reviewed. This includes “conventional” T1 and T2 weighted sequences to characterise tissue, but also diffusion weighted imaging, quantitative methods for fat and iron, and non-contrast MRA. Functional methods under active investigation including BOLD and ASL will be briefly discussed, time permitting.
A few clinical scenarios where contrast is relatively contra-indicated or not necessary will be discussed. These include:
1. Suspected abdominal/pelvic pathology in the pregnant patient. Efficient imaging is necessary in this setting, particularly in third trimester patients.
2. Patients with acute or severe chronic renal impairment. Risk vs benefit of contrast needs to be carefully weighed in this population.
3. Tumour detection or surveillance where contrast might not always be required, e.g. rectal carcinoma.
4. The acutely unwell patient with right upper quadrant pain.
5. Gynaecologic pathology, e.g. uterine anomalies.
6. Fat and iron quantification within the body.
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