Intracranial dermoid cyst and colloid cysts of the third ventricle are rare benign congenital lesions of early adulthood. Both lesions are thought to be congenital in origin however association is rare.
Cheng et al. from the Department of Neurosurgery, Stanford University School of Medicine in 1999 reported a case of nasal dermoid sinus cyst associated with colloid cyst of third ventricle and proposed a fascinating theory of “anterior neuropore corridor defects” to explain the spectrum of these associated rare midline lesions. According to this theory, defective closure of situs neuroporicus promotes the neuroepithelium adjacent to commissural plate derivatives to form a vacuolated paraphysis growing slowly as colloid cyst of the third ventricle
The reported case was a 16-year-old male with both a nasal dermoid sinus cyst (NDSC) and a third ventricle colloid cyst. The NDSC was excised via a single-stage combined intracranial-extracranial approach and the third ventricle colloid cyst was resected endoscopically 1).
Kurwale et al. report a 22-year-old male with suprasellar dermoid cyst and colloid cyst of the third ventricle presenting simultaneously 4).