Purpose or Case Report: Three cases of dermoid cyst will be described with different clinical presentation and location. MRI and CT finding will be reviewed and correlated with pathological finding.
The first case is a 7 year- old child, with suspected diagnosis of stroke which MRI shows a midline posterior fossa tumor with fine occipital dermal sinus, better visualized in CT. The second case is 1 year- old enfant with delayed psychomotor development, a dimple with lock of hair and dorsal hemangioma, which MRI shows a dermal sinus at D4 – D5 level which continues with an intra and extramedullary mass. The last case is 2 year- old child postoperated of mielomeningocele at birth that has neurogenic blader and Chiari II with a cyst mass at conus and low spinal cord insertion.
Methods & Materials:
Results:
Conclusions: Intracranial dermoid cyst are uncommon . The typical MRI finding are hypointense T1 and hyperintense T2 signal that not enhance after contrast administration but can be hyperintense on T1 becouse of high lipid content.
Congenital dermal sinuses can occur anywhere along the craniospinal axis and dermoid cyst of posterior fossa associated with dermal sinus are rare. Dermal sinus is a defect in neural tube closure that occurs during the fifth week of embryonic development, characterized by tract lined coated by epithelium dural extending toward the skin surface within the central nervous system.
Spinal dermoid cyst are benig tumors that results from congenital or adquired ectodermal inclusion. These tumor account 0,8 – 1,1% of all primary spinal tumors, the majority in the extramedullary lumbosacral region and can be associated with low spinal cord insertion and dermal sinus.

Pathological finding show cystic structure with pearly white content, presence of hair shafts, hair follicle and sebaceous glands.