December 20, 2018
A 2-year-old girl with agenesis of the septum pellucidum and an abnormal corpus callosum found to have a non-tender, midline cervical dimple.
Cervical spine dermal sinus tract (DST)
- Background
- DST are developmental remnants of neural tube closure when there is incomplete or absent separation of cutaneous ectoderm from neuroectoderm during early embryonic life, resulting in epithelium-lined tracts extending from the skin surface to the dura, spinal cord, or nerve roots.
- Approximately 50% of dermal sinuses are associated with dermoid and epidermoid tumors. Reported incidence is 1:2,500 live births and affects both genders equally. Most common locations are lumbosacral spine (60%), occipital region (25%), thoracic (10%) and cervical spine (1%).
- Clinical Presentation
- Skin dimple or tag, hyperpigmented skin or hairy patch, hemangiomas, subcutaneous lipomas, or meningoceles on the skin superficial to the DST.
- Complications include infection (abscess or meningitis), cord or nerve root tethering/compression, and split cord malformations (diastematomyelia or diplomyelia).
- Key Diagnostic Features
- DSTs are usually hypointense on T1 and hyperintense on T2, and may enhance after gadolinium injection, especially if infected.
- One must describe: the tract’s length, termination, site of dural penetration, and associated features such as osseous anomalies (bifid laminae), cord tethering, inclusion tumors, or signs of infection.
- Differential Diagnosis
- Midline dimples without DST are skin or subcutaneous tissue anomalies that may or may not be depicted on radiological images.
- Epidermoid or dermoid tumors without DSTs are seen as spinal masses without a tract. Epidermoids show restricted diffusion while dermoids may show mixed intensity due to water and fatty contents.
- Treatment
- Surgical excision of sinus tract with or without tethered cord release/inclusion tumor resection.
