What is the recommended MRI protocol for evaluating scoliosis of the spine?

MRI Protocol for Evaluating Scoliosis of the Spine

For scoliosis evaluation, MRI should include complete spine imaging without contrast, focusing on detecting intraspinal abnormalities, particularly in patients with congenital scoliosis or those with risk factors for neural axis anomalies. 1

Initial Assessment Before MRI

• Radiography is the primary initial imaging modality for diagnosing and classifying scoliosis, evaluating severity, and monitoring progression 1
• MRI is selectively used after radiography to detect and characterize suspected intraspinal abnormalities 1
• Physical examination should assess for risk factors requiring MRI, including left thoracic curve, short segment curve, absence of apical segment lordosis/kyphosis, rapid curve progression, functionally disruptive pain, focal neurological findings, and male sex 1, 2

MRI Protocol Components

• Complete spine imaging (cervical, thoracic, and lumbar) should be performed 1
• T1 and T2-weighted sequences in sagittal and axial planes to evaluate neural elements and potential abnormalities 1
• No intravenous contrast is required for routine scoliosis evaluation 1
• Gadolinium-based contrast agents should only be used when tumor or infection is suspected 1

Specific Patient Populations and MRI Indications

Congenital Scoliosis

• MRI is strongly recommended for all patients with congenital scoliosis 1
• Neural axis anomalies occur in more than 20% of patients with congenital scoliosis 1
• Common findings include tethered cord, filar lipoma, syringohydromyelia, and diastematomyelia 1
• History and physical examination alone have limited accuracy (62%) for diagnosing intraspinal anomalies 1

Idiopathic Scoliosis

• Selective MRI is recommended based on risk factors 1
• 2-4% of adolescents with idiopathic scoliosis have intraspinal abnormalities detectable only by MRI 1
• Most common abnormalities include Chiari I malformation, cord syrinx, cord tethering, and rarely, intrinsic spinal cord tumors 1
• Risk factors for neural axis abnormalities include left thoracic curve, short segment curve, absence of apical segment lordosis, rapid curve progression, pain, neurological findings, male sex, and pes cavus 1, 2

Early-Onset Scoliosis

• Higher rates of abnormal MRI findings (24% overall) with variations by scoliosis type 3
• Syrinx and tethered cord are the most common findings in early-onset scoliosis 3

Clinical Considerations and Pitfalls

• Absence of neurological symptoms does not rule out intraspinal abnormalities 1, 4
• Preoperative MRI is particularly important for surgical planning and to reduce potential complications 1
• Pain in scoliosis patients may be related to inflammatory end plate changes visible on MRI, particularly at the apex of curvature or lumbosacral junction 5
• In pediatric patients with pain, look specifically for Schmorl's nodes which correlate with increased pain 5
• The clinical relevance of some intraspinal abnormalities remains unclear, even in presurgical settings 1

When to Consider Alternative Imaging

• CT may be preferred for presurgical planning and visualization of bony malformations 1
• Low-dose CT protocols should be used when CT is necessary 1
• For painful scoliosis where tumor is suspected and MRI is contraindicated, CT with contrast may be considered 1