Myelogram

A myelogram remains a valuable tool in specific clinical situations:

• When MRI is not immediately available and urgent surgical planning is needed for a dog losing neurological function
• When CT alone does not clearly identify the side or level of compression in a dog with multilevel disc disease
• To evaluate suspected spinal cord tumors or instability that requires dynamic positioning not possible in an MRI scanner
• When a patient's size, metal implants, or pacemaker makes MRI unsuitable

For intervertebral disc disease (IVDD) — the most common reason a dog needs spinal surgery — a myelogram guides the surgeon to the exact disc space, reducing operative time and unnecessary tissue dissection.

The myelogram is performed under general anesthesia in the following steps:

• The pet is positioned and a small area over the lower back (lumbar) or base of the skull (cisterna magna) is clipped and aseptically prepared
• A spinal needle is placed into the subarachnoid space under fluoroscopic or tactile guidance, and a small amount of cerebrospinal fluid (CSF) may be collected for analysis
• Iodinated contrast dye is slowly injected into the fluid column
• A rapid series of X-rays or a CT scan is performed with the patient in various positions — the contrast column fills around the cord, and any compression causes a visible narrowing or deviation
• The exact level and side of compression are identified and documented for the surgeon

The procedure typically takes 30–60 minutes from induction to imaging completion.

Before a myelogram, neurological assessment scores the pet's degree of weakness, pain response, and bladder function — this baseline is essential for tracking recovery after any intervention. Standard pre-anesthetic bloodwork is run. Food is withheld for at least eight hours before the procedure. If spinal cord compression is causing severe neurological signs — for example, a dog that has lost the ability to walk — the myelogram is often scheduled as an urgent same-day or next-morning procedure, followed immediately by spinal decompression surgery if the imaging confirms a surgically addressable lesion.

Most pets recover from a myelogram within a few hours and are ready for surgery the same day if needed. Immediately after the procedure, some animals experience mild post-contrast side effects:

• Transient seizure-like activity (very uncommon but the team is prepared) — typically brief and self-limiting
• Mild head or neck stiffness for 12–24 hours
• Temporary worsening of neurological signs in rare cases — almost always resolves within hours

Pets undergoing myelogram as part of a same-day surgical workup move from imaging directly to the operating room, minimizing total anesthesia time.

A myelogram is a well-established procedure with a good safety profile when performed by experienced practitioners. The most significant risk is contrast-induced seizure activity, which occurs in a small minority of cases and is typically brief and self-limiting. The team is fully prepared to manage this event. Post-procedure inflammation (arachnoiditis) is uncommon with modern low-osmolality contrast agents. In the hands of our surgical team, the benefit of precise lesion localization for a dog with progressive neurological deterioration — particularly one who is losing the ability to walk — almost always outweighs the procedural risk. The decision is made on a case-by-case basis with full owner discussion.