Feature

MRI for Emergency Clinicians

Emergency Medicine. 2018 December;50(12):1-6

References

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Musculoskeletal infections

A wide variety of bone, joint, and soft-tissue infections can be diagnosed by MRI, which is often the imaging modality of choice. Some of these infections may be limb- or even life-threatening. One, epidural abscess, is both life-threatening and function-threatening and has been discussed briefly already.

If you are concerned about the possibility of a serious soft-tissue or bone infection, strongly consider giving gadolinium contrast, which is particularly useful for detecting abscesses, sinus tracts, and spine infections, and for providing other important anatomic details.²⁵

Conclusion

MRI utilization by EPs will continue to increase as the factors governing its use evolves. These factors include: decreasing scan times; wider availability; possible cost reductions; new and changing indications; more research; and the always-present pressure on EPs to care for a broader spectrum of evermore challenging patients. It therefore benefits us to understand more about this dynamic part of our practice. Look to the scientific literature on stroke, neurosurgical emergencies, orthopedics, pediatrics, infectious disease and other fields that impact emergency medicine practice and MRI use as they continue to change.

SIDEBAR
Summary of Cautions and Limitations of MRI Use

Lack of availability

Cost

Exam completion time

Claustrophobia

Patient’s inability to lie still

Implanted medical devices

Metallic foreign bodies

Obesity

Hearing damage

Pregnancy

Pediatric patients (the developing brain)

Nephrogenic systemic fibrosis due to gadolinium-based contrast agents

SIDEBAR
Common ED MRI indications

Central Nervous System
- Spinal cord compression
- Dural venous sinus thrombosis
- Arterial dissections - carotid or vertebral
- Meningoencephalitis and vasculitis evaluation (possible)
- Subarachnoid hemorrhage (possible)
- Cerebral ischemia - TIA/Stroke

Spinal cord/surrounding structure disease or trauma - epidural abscess, cauda equina syndrome, cord/nerve trauma

Pregnant patients with abdominal pain (concern for appendicitis)

Children with abdominal pain (concern for appendicitis)

Musculoskeletal infections Orthopedic trauma