A myelogram is an imaging procedure in which contrast dye is injected into the spinal canal (subarachnoid space) via lumbar puncture, then X‑rays or CT scans are taken to visualize the spinal cord, nerve roots and surrounding structures. It helps detect disc herniation, spinal stenosis, tumors, infections or CSF leaks and is used when MRI is inconclusive or not possible. Risks include headache, infection, bleeding, and allergic reaction.

A myelogram is usually only mildly to moderately uncomfortable. Local anesthetic numbness makes the needle insertion feel like pressure or a brief pinprick; some people feel short, sharp or shooting pains if a nerve is touched. Most tolerate it well, but headaches, back soreness, or nausea are common afterwards; serious complications like nerve injury or infection are rare.

The myelogram procedure itself usually takes about 30–60 minutes. Including preparation, contrast injection, any follow-up imaging (often a CT), and a post‑procedure observation period, plan to be at the facility for roughly 2–4 hours. You’ll receive local anesthetic and contrast, may be monitored for headaches or reactions, and should arrange someone to drive you home.

CT myelogram is generally safe. The commonest complication is a post‑lumbar puncture headache from CSF leak (about 10–30%). Less common risks include infection or bleeding (<1%), mild contrast reactions; severe allergic reaction or permanent nerve injury is very rare. CT adds modest radiation. Risks rise with pregnancy or anticoagulation—discuss meds, allergies and report severe symptoms to your clinician.

Recovery after a myelogram is usually quick. You'll be observed for several hours and may be asked to lie flat for a few hours to reduce spinal headache risk. Common aftereffects include headache, nausea, neck or back pain and mild dizziness; drinking fluids, resting and simple analgesics help. Avoid heavy lifting or driving for 24–48 hours. Seek urgent care for high fever, severe headache, worsening weakness, numbness, or allergic signs.

A myelogram is highly accurate for detecting spinal canal blockages, nerve‑root compression, CSF leaks and bony pathology, and CT myelography often equals MRI when MRI is contraindicated. Accuracy varies by condition and technique; sensitivity and specificity are generally high but operator‑ and timing‑dependent. Limitations include invasiveness, radiation exposure, lower sensitivity for some soft‑tissue lesions and possible false negatives with intermittent compression.