Myelography with Omnipaque (Iohexol) using basic radiographic facilities: the main adverse effects

Area of Science:

• Radiology and Imaging
• Neurology
• Patient Safety

Background:

• Myelography is a diagnostic imaging procedure used to visualize the spinal canal.
• Assessing adverse effects of contrast media is crucial for patient safety, especially in resource-limited settings.
• Omnipaque is a commonly used non-ionic, low-osmolar iodinated contrast medium.

Purpose of the Study:

• To document adverse effects of different Omnipaque concentrations during myelography.
• To evaluate the relationship between contrast concentration and adverse event severity.
• To inform optimal contrast selection for myelography under basic radiographic conditions.

Main Methods:

• Prospective, double-blind study comparing myelography with varying Omnipaque concentrations (180, 240, 300) to diagnostic lumbar puncture.
• 110 neurological patients undergoing myelography and 30 controls undergoing lumbar puncture were included.
• Adverse effects (headache, dizziness, nausea, vomiting, convulsions) were assessed and graded by a blinded neuro-physician.

Main Results:

• Overall adverse effects occurred in 63.6% of myelography cases versus 36.7% of controls (p < 0.05).
• Omnipaque concentrations of 180 and 300 were significantly associated with adverse effects (p = 0.017 and 0.016).
• Omnipaque 240 showed no significant difference in adverse effects compared to diagnostic lumbar puncture (p = 0.137).

Conclusions:

• Myelography with Omnipaque 240 is a relatively safe option, comparable to diagnostic lumbar puncture, even with limited radiographic facilities.
• The choice of Omnipaque 240 is recommended for myelography in sub-optimal radiographic settings.
• While higher concentrations (180 and 300) are associated with tolerable adverse effects, 240 offers a favorable safety profile.