Transillumination of an Anterior Fontanelle Dermoid Cyst.

Dermoid cysts are slowly growing benign lesions of ectodermal tissue that often occur in the anterior fontanelle. Clinicians often rely on a negative transillumination test to begin the process of correctly diagnosing a dermoid cyst. However, here the authors present a case of a 7-month-old girl who presents with a transilluminating dermoid cyst.