MRI Spinal Cord is the Most Appropriate Diagnostic Test
This patient requires urgent MRI of the spinal cord without contrast immediately, as this presentation represents a neurologic emergency consistent with spinal cord compression. 1
Clinical Reasoning
This patient's constellation of symptoms—lower limb weakness, urinary incontinence, difficulty walking, and a T10 sensory level developing over 3 days—represents classic signs of acute spinal cord compression or cauda equina syndrome that demands immediate imaging. 1, 2
Why MRI is Superior to CT
MRI is the imaging study of choice for suspected spinal cord compression because it accurately depicts soft-tissue pathology, evaluates the spinal cord parenchyma itself, and assesses vertebral marrow—capabilities that CT cannot match. 1
CT is inferior for this purpose according to the ACR Appropriateness Criteria, as it cannot adequately characterize the etiology of spinal cord compression or visualize the spinal cord tissue itself. 1
MRI visualizes the spinal cord and nerve roots in multiple planes and is superior for detecting intraspinal cord parenchymal lesions, including neoplasms, infections, inflammatory processes, and vascular events. 3, 4
Critical Time-Sensitive Considerations
Time is critical in diagnosing spinal cord compression—delayed diagnosis leads to irreversible neurologic damage and poor outcomes. 1
Progressive neurologic deficit over a short period (3 days in this case) represents a neurologic emergency requiring prompt imaging to identify the cause and guide urgent intervention. 1, 2
Urgent neurosurgical consultation should occur simultaneously with imaging, as surgical decompression may be required within hours. 1
Common Pitfalls to Avoid
Do not order CT as the initial imaging modality—it will delay definitive diagnosis and potentially worsen outcomes by missing soft tissue pathology, cord edema, or intramedullary lesions. 1
Do not wait for additional workup or conservative management—this presentation requires immediate action given the risk of permanent paralysis and loss of bowel/bladder function. 1, 2