CT recognition of lateral lumbar disk herniation

Area of Science:

• Radiology
• Neurosurgery
• Orthopedics

Background:

• Computed tomography (CT) is established for diagnosing central and posterolateral lumbar disc herniations.
• Myelography may struggle with lateral herniated discs due to lack of dural sac deformity.

Observation:

• A review of 274 lumbar disc herniation CT scans identified 14 cases (5%) of lateral herniation.
• Lateral herniations presented with focal disc protrusion, displaced epidural fat, and soft-tissue masses within or lateral to the intervertebral foramen.

Findings:

• CT demonstrated key features of lateral disc herniation: focal protrusion, epidural fat displacement, absence of dural sac deformity, and a soft-tissue mass.
• These CT findings are crucial for identifying lateral disc herniations, which may not deform the thecal sac or nerve root sheath.

Implications:

• CT imaging may be superior to myelography for detecting and assessing the extent of lateral lumbar disc herniations.
• Accurate CT interpretation can improve diagnostic yield for this specific type of lumbar disc pathology.