Korean J Pain.  2010 Sep;23(3):202-206. 10.3344/kjp.2010.23.3.202.

Air Bubbles Mimic Disc Herniation in MRI after Cervical Epidural Block

• Kim TS
• Shin SS
• Kim JR
• Kim DY

• KMID: 1767883
• DOI: http://doi.org/10.3344/kjp.2010.23.3.202

Abstract

Magnetic resonance image (MRI) is the most sensitive imaging test of the spine in routine clinical practice. Unlike conventional x-ray examinations and computed tomography scans, high-quality magnetic resonance images can be assured only if patients are able to remain perfectly still. However, some patients find it uncomfortable to remain still because of pain. In that condition, interlaminar cervical epidural injections can reduce pain and allow the procedure. When using air with the "loss of resistance" technique in epidural injections to identify the epidural space, there is the possibility of injected excessive air epidurally to mimic a herniated disc. We describe a case report of epidural air artifact in a cervical MRI after cervical epidural injections.

Keyword

artifact; epidural injections; herniated disc; magnetic resonance image

MeSH Terms

Artifacts
Epidural Space
Humans
Hydrazines
Injections, Epidural
Intervertebral Disc Displacement
Magnetic Resonance Spectroscopy
Spine
Hydrazines

Figure

• 

  Fig. 1 T2 sagittal image after cervical epidural block shows low signal intensity lesion at C3-C4 and C5-C6. These lesion are considered herniated disc.

• 

  Fig. 2 CT axial image (A) shows low density lesion behind C3-C4 disc. At CT, it seems like the air, not herniated disc. Low signal intensity lesion behind C3-C4 disc seems new compared MRIs before and after cervical epidural block. There is no lesion behind C3-C4 disc in MRI before cervical epidural block (B). (C) and (D) show air as a low signal intensity. By contrast, (E) and (F) show C5-C6 herniated disc relatively higher intensity than lesion behind C3-C4.

• 

  Fig. 3 Post-op. T2 sagittal image. There is no air behind C3-C4 disc.

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