II. Epidemiology
- Dermatologic signs seen in 50-90% of Spinal Dysraphism
- Skin findings may be only signs of occult lesion
III. Findings
- High Risk Findings (Lumbosacral MRI is preferred imaging modality)
- Midline Lipoma
- Dermal sinus
- Appears as large midline dimple above gluteal crease
- Do not probe dimple
- Moderate risk findings (Lumbosacral MRI or Ultrasound)
- Aplasia Cutis Congenita
- Atypical sacral dimple
- Gluteal furrow is deviated to one side
- Low risk findings (1 present: Consider Ultrasound; 2 present is a high risk finding)
- Hypertrichosis
- Midline Hemangioma (e.g. sacral Hemangioma)
- Mongolian Spot
- Nevus Simplex
- Port wine stain
- Small sacral dimple (normal if within gluteal crease or simple as described below)
IV. Findings: Sacral Dimple
- Simple sacral dimples do not require additional evaluation
- Shallow sacral dimple <0.5 cm in diameter AND
- Within 2.5 cm from anal verge
- And no hairy patches or Hemangiomas
- Further evaluate sacral dimples that do not meet these criteria or other midline defects
- Atypical dimples >5 mm or >25 mm from anal verge
- Deep or multiple dimples
- Dimples superior to gluteal crease, or offset from midline
V. Imaging
- Lumbosacral Ultrasound for Spinal Dysraphism
- Indicated in moderate risk findings in age <3 months (see above)
- Perform by 3 months of age (Vertebral body ossification in older infants obscures the Ultrasound)
- Typical, but is controversial, as it may not change management
- Spinal MRI
- Indicated in high risk findings or infants age >3 months
- Consider pediatric neurosurgery Consultation prior to imaging
- MRI in infants requires sedation