Occipital Dermal Sinus:  Clinical and Radiological Findings When a Complete Occipital Dermal Sinus Is Associated with a Dermoid Cyst

The purpose of this paper is to call attention to the high incidence of intracranial infection (meningitis, cerebral abscess) when a complete occipital dermal sinus is associated with a dermoid cyst. In addition, important clinical and radiological findings are stressed that should make one suspicious when this condition is present. The congenital dermal sinus represents a midline defect whereby the dermal sinus opening in the skin is connected by a tract to a dermoid cyst in the posterior fossa. This pathway is a direct source of intracranial infection. The sinus tract extending through the occipital bone causes a bony defect which can be diagnosed radiologically. These radiological findings were mentioned by Matson and Ingraham² in 1951 and later clarified by Logue and Till³ in 1952. During the past 10 years 17 cases have been published (Table 1), to which we are adding two additional cases.

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