Rudimentary meningoceles represent a developmental anomaly in which meningothelial elements are found in the skin. The majority of rudimentary meningoceles occur on the scalp over the occiput or along cranial suture lines. They are present as a pink p...
Rudimentary meningoceles represent a developmental anomaly in which meningothelial elements are found in the skin. The majority of rudimentary meningoceles occur on the scalp over the occiput or along cranial suture lines. They are present as a pink papule, nodule or an area of alopecia. Histologically, the lesion consists of scattered foci of meningothelial cells, an anastomosing network of empty spaces with psammoma bodies and collagen bodies, and small vessels, which may be located from the dermis to the subcutis. Immunohistochemically, the meningothelial cells are commonly positive for vimentin and often positive for EMA. We report the cases of two infants who were noted at birth to have scalp hair anomalies. One had a translucent, bald, slightly atrophic patch on the midline of the vertex and the other had a subcutaneous nodule surrounded by long hairs, so called hair collar sign on the midline of the occipital area. The latter had an underlying skull defect without a communication with intracranial spaces. Due to the occasional presence of connection to the central nervous system, any midline lesion in an infant, including rudimentary meningocele, deserves careful preoperative evaluation including imaging studies.