What are the red flags after a myelogram that require immediate medical attention?

Red Flags After a Myelogram Requiring Immediate Medical Attention

Patients should seek immediate medical attention if they develop new-onset severe back or leg pain, lower limb motor weakness or sensory disturbance, urinary or fecal incontinence, urinary retention, perineal sensory disturbance, nausea and vomiting, or fever following a myelogram procedure. 1

Neurological Red Flags

• New or worsening motor weakness in the extremities may indicate compression of the spinal cord or nerve roots, potentially from a procedure-related complication such as subarachnoid hematoma 2, 3
• Sensory disturbances including numbness, tingling, or paresthesias, particularly if progressive or severe, may indicate nerve root compression or irritation 1
• Bladder or bowel dysfunction including urinary retention, incontinence, or fecal incontinence requires urgent evaluation as these symptoms suggest potential cauda equina syndrome 1
• Perineal sensory disturbance (saddle anesthesia) is particularly concerning for cauda equina syndrome and warrants immediate medical attention 1
• Altered consciousness or meningeal signs including neck stiffness, photophobia, or altered mental status may indicate subarachnoid hemorrhage or meningitis 2, 3

Pain-Related Red Flags

• Severe or worsening headache that differs from the typical post-myelogram headache pattern (especially if accompanied by nausea, vomiting, or neurological symptoms) may indicate intracranial hemorrhage or increased intracranial pressure 3
• New onset severe back pain that is different from the patient's baseline pain or the expected post-procedural discomfort may indicate a procedure-related complication 1, 2
• Radicular pain that is severe, new, or significantly worsened compared to pre-procedure symptoms may indicate nerve root irritation or compression 2

Systemic Red Flags

• Fever following myelography may indicate infection such as meningitis or epidural abscess and requires immediate evaluation 1
• Nausea and vomiting that is severe or persistent may indicate increased intracranial pressure or other complications 4, 3
• Change in the nature and site of headache particularly if it represents a reversal of orthostatic symptoms (relief when upright, worse when recumbent) may indicate rebound intracranial hypertension following treatment of CSF leak 1

Potential Serious Complications

• Subarachnoid hematoma is a rare but serious complication that can present with severe back pain, progressive neurological deficits, and even altered consciousness 2, 3
• Hydrocephalus may develop after myelography, particularly if blood enters the ventricular system, presenting with headache, nausea, vomiting, and altered mental status 3
• Aseptic meningitis can occur following myelography and presents with headache, neck stiffness, photophobia, and fever 3
• Rebound intracranial hypertension can occur following treatment of CSF leaks (such as with epidural blood patches) and presents with headache that worsens when lying down and improves when upright 1

Risk Factors for Complications

• Coagulopathy increases the risk of subarachnoid hematoma following lumbar puncture for myelography 2
• Larger needle size (22-gauge vs. 25-gauge) is associated with more frequent adverse effects following myelography 4
• Normal myelogram findings are paradoxically associated with more reported adverse effects, possibly due to other undiagnosed causes of symptoms 4

Remember that while most post-myelogram symptoms are mild and self-limiting, the red flags described above require immediate medical evaluation to prevent potentially serious or permanent complications.