Dermal sinus are a potential pathway for infections within the dura mater, and may result in meningitis and/or an abscess. The contents of the dermal sinus causing sterile (chemical) meningitis may also irritate the skin.
If the tract expands into the thecal sac (the sac that contains the spinal cord) to form a cyst, the mass may appear as a tethered cord. In these circumstances bladder dysfunction usually occurs.
García Galera et al. present a case of a dermoid cyst associated with an infected dermal sinus and posterior development of cerebellar abscesses and hydrocephalus 1).