Imaging recommendation · Neuro · Head & Neck

Sacral dimple, hair tuft, or tethered cord symptoms in child, suspected spinal dysraphism

Q: What's the alternative imaging for sacral dimple, hair tuft, or tethered cord symptoms in child, suspected spinal dysraphism when mri for definitive characterization?

MRI — MRI Lumbar Spine (no contrast).

Recommended: Spinal Ultrasound (infant) or MRI Spine (older child) is the preferred imaging study for sacral dimple, hair tuft, or tethered cord symptoms in child, suspected spinal dysraphism. Spectrum: open (myelomeningocele), closed (lipomyelomeningocele, tethered cord, dermal sinus).

Recommended study

Spinal Ultrasound (infant) or MRI Spine (older child)

US No contrast Preferred Neuro · Head & Neck Outpatient Reviewed 2026-05

Spectrum: open (myelomeningocele), closed (lipomyelomeningocele, tethered cord, dermal sinus). Cutaneous stigmata are clues.

If the default doesn't apply

MRI for definitive characterization

MRI MRI Lumbar Spine No contrast

Watch-outs

Tethered cord progressive symptoms

Bladder dysfunction, leg weakness, scoliosis — surgical untethering may halt progression.

Dermal sinus + infection risk

Communicates with intrathecal space; meningitis / abscess risk.

Pearls

Conus medullaris below L2-3 in child > 3 months = abnormal (tethering).
Filum thickening > 2 mm — abnormal.
Ultrasound first-line for infants while spinous processes incompletely ossified (< 6 months).