Intrathecal and Intraarticular Contrast Administration

Monday, March 20, 2017

Intrathecal Contrast Administration

Although this procedure is rarely performed in the CT scan department, contrast media can be injected into intrathecal space surrounding of the spinal cord. Only certain iodinated contrast media can be safely used intrathecally. Serious adverse reactions have been reported as a result of the inadvertent intrathecal administration of iodinated contrast media that are not indicated for intrathecal use. These serious adverse reactions include:

Death
Convulsions
Cerebral Hemorrhage
Coma
Paralysis
Arachnoiditis
Acute renal failure
Cardiac Arrest
Seizures
Rhabdomyolysis
Hyperthermia
Brain Edema

In fact, the US food and Drug Administration requires the manufacturers of contrast media that are not intended for this use to mark the packages ‘not for intrathecal use’ or ‘not for myelography.’ When these contrast media is to be used and administered intrathecally, radiology staff should perform an independent double check to make sure the product they are using is the right one for that purpose. Intrathecal injection is outside the scope of practice of CT scan technologist.

Patient are frequently sent to the CT scan department for a post-myelogram CT study, while the contrast medium is still in the intrathecal space. There this contrast media is injected before the arrives for the CT scan study. To reduce the incidence of headache, keep the patient’s head elevated in approximately 30 degrees. The CT scan examination is typically done from 1 to 3 hours after the intrathecal injection. If the examination is done too soon the contrast material may be too dense and generate streak artifact. Rolling the patient once or twice before scanning is recommended to mix the contrast material that may have settled since the myelogram.

Intrathecal Contrast Administration through Lumbar Puncture

Intraarticular Contrast

Contrast media can also be injected directly into a joint space to better visualize the soft tissue structures of the joint. Arthrography can be performed with the use of fluoroscopy in the general conventional radiography department, or more commonly this procedure is done in MRI department. However, CT arthrography has the advantage of allowing the simultaneous evaluation of bone and soft tissue. The intraarticular contrast injection is performed by the radiologist, most often under fluoroscopy guidance. Once the contrast has been injected into the joint space the patient is transported to the CT scan department for the study begins.