CT Myelogram - Uses, What To Expect, and Associated Risks

Introduction

To diagnose and treat a variety of disorders affecting the vertebral column, the radiographic examination of spinal anomalies is essential. Healthcare workers can learn a lot about structural integrity and disease of the spine by using imaging modalities like X-rays, CT scans, and MRIs. Spinal fractures, degenerative disc disease, herniated discs, spinal stenosis, and spinal malignancies are just a few of the disorders that radiographic results can identify. These visual evaluations assist in establishing the degree of injury, locating the underlying source of symptoms, and directing the most suitable treatment options. In addition, a diagnostic imaging procedure called myelography is performed to see the spinal cord, nerve roots, and other tissues which requires the injection of a contrast dye. In comparison to traditional myelography, CT myelography offers detailed and high-resolution pictures that are more accurate and enable a better assessment of spinal abnormalities. This article explores the value and significance of CT Myelogram in defining spinal anomalies and supporting focused treatment therapies.

What Is a CT Myelogram?

A CT myelogram is a diagnostic test that uses contrast material and computed tomography (CT) to diagnose any abnormalities in the spinal cord. This test is also known as myelography. A CT myelogram is extremely useful as it gives an accurate and elaborate image of the spinal canal, spinal cord, nerve roots, and subarachnoid space. MRI is usually preferred to diagnose any pathologic spinal conditions as it is non-invasive, has high-contrast resolution images, and has negligible ionizing radiation. In situations where MRI and conventional X-rays cannot be used to diagnose the problems, a CT myelogram can prove vital, such as in patients in whom MRI is contraindicated, such as patients with implants and pacemakers.

What Are the Uses of CT Myelograms?

• To detect any structural changes or abnormalities in the spinal cord and its associated areas.

• Intervertebral disk herniation.

• Nerve root or spinal cord compression.

• To diagnose spinal stenosis.

• Degenerative spinal diseases.

• To assess the patency of cerebrospinal fluid (CSF) spaces.

• Cysts or tumors in the spinal cord, nerve root, or meninges.

• Infection or inflammation.

• Spinal joint arthritis.

• Ankylosing spondylitis (an inflammatory condition of the spine resulting in the fusion of the vertebral bones).

• It is used in patients with rods, screws, or plates in the spinal cord as these instruments can impede the diagnosis with an ordinary MRI.

• A persistent back pain where an ordinary MRI or CT is inconclusive.

• In cases where post-surgical complications such as weakness or persistent pain have developed.

How Should the Patients Prepare for the Procedure?

• Patients are advised to avoid solid foods for 6 hours before the test; however, they should consume an increased amount of clear fluid right from a day before the test. Hydration is essential for this procedure. Patients can consume any clear fluid such as water, black coffee, soda, or juice before the procedure.

• Any history of allergies should be mentioned to the doctor.

• If the patient is on antibiotics for any active infection, they should wait till the complete course of antibiotics is over before the procedure.

• Patients on blood thinners may need to stop these medicines.

• Pregnant ladies should inform the radiologist before the procedure.

• Diabetic patients with an insulin pump or glucose monitors should also inform the radiologist as the devices can malfunction due to the imaging machines.

• Patients on antipsychotic or anti-epileptic drugs also need to stop these medicines 24-48 hours before the procedure as they can cause seizures.

• Patients should wear comfortable loose clothing.

• Remove all the jewelry and accessories before the procedure.

• Patients are advised to carry their other test reports, if any, and their routine prescription medicines.

How Is a CT Myelogram Done?

A CT myelogram is usually done on an outpatient basis. Patients must change into a hospital gown before proceeding. They would be made to lie either on their side or their stomach, depending on the site of the injection. Before starting the procedure, patients are advised to empty their bladder. Their lower back is cleaned using an antiseptic solution. The area is draped with sterile towels. A local anesthetic is used to numb the area. The patient may feel a burning sensation when the local anesthetic is injected. The radiologist uses a fluoroscope and a needle to puncture the skin after it has become numb. The presence of free slow spinal fluid flowing out will serve as confirmation that the needle has been placed into the subarachnoid space within the canal. This fluid can also be sent for laboratory analysis. The patient might experience some pressure as the needle is inserted inside. Contrast material will be injected through the needle into the spinal canal. The patient might experience a warm sensation when the dye flows in. The X-ray table is tilted so that the dye moves up and down and covers the area of interest. The needle is then removed. CT images may then be taken.

What Are the Patient Instructions After the Procedure?

• Patients are advised to lie down flat on their backs, keeping their heads elevated for at least two hours after the procedure to prevent any cerebrospinal fluid leak.

• Should drink as many clear fluids as possible to clear out the contrast material from the body and also to replenish the lost spinal fluid.

• Should avoid smoking and alcohol.

• Analgesics can help alleviate the pain of positional headaches. Some people may require an epidural blood patch to treat chronic headaches.

• Should avoid any strenuous activity or lifting heavy objects for 24-48 hours.

What Are the Benefits of a CT Myelogram?

• It is a relatively safe procedure.

• Minimal radiation exposure.

• Highly effective than X-ray or MRI to view the spinal cord and its associated structures.

• The spatial resolution of the images obtained with a CT myelogram is much higher than those obtained from a conventional MRI.

What Are the Risks Associated With CT Myelogram?

• An allergic reaction to the contrast material.

• A possibility of seizure as the contrast material is injected into the (CSF).

• A persistent headache due to a constant CSF leak.

• Chances of infection (meningitis).

• Risk of bleeding.

• Temporary weakness in the lower extremities.

• Slight radiation exposure.

When Should An Individual Seek Medical Advice?

• Persistent pain at the site of injection.

• Fever.

• Drainage from the injection site.

• A sudden sense of weakness in the lower extremities.

• Difficulty urinating.

• Persistent headache for more than 24 hours.

• Nausea, vomiting, stiff neck.

What Are the Limitations a of CT Myelogram?

• Contraindicated in pregnant ladies.

• Not advisable in patients with active spinal column infection.

• Difficult to perform in patients with spinal injury or any structural abnormalities.

Conclusion:

There are various problems affecting the spinal cord, spinal column, or its adjoining structures. Though CT, MRI, and X-rays are conventional modes of diagnosis, they cannot be used at all times. In such situations, a CT myelogram plays a vital role in diagnosing spinal diseases. Also, it provides more precise details concerning spinal anatomy and structure. A conclusive diagnosis is essential for prompt treatment and a better prognosis.