Fig. 1

Diagrams showing the anatomy of the nasofrontal region and its related pathologies. a Normal anatomy. Frontal bone (FB), fonticulus frontalis (FF), nasal bone (NB), nasal septum (NS), foramen cecum (FC), prenasal space (dotted line), and crista galli (CG). It is believed that during development, the dura mater projects through the fonticulus frontalis or more inferiorly into the prenasal space. This dural element normally regresses and its faulty regression leads to congenital nasofrontal masses. b Nasofrontal encephalocele. The dotted line shows the path for the development of nasofrontal encephalocele and has a connection with the intracranial structures. If there is no connection between herniated content and intracranial structures, it is called as extra-nasal glioma. c Nasoethmoidal encephalocele. The dotted line shows the path for the development of nasoethmoidal encephalocele and has a connection with the intracranial structures. If there is no connection between herniated content and intracranial structures, it is called an intra-nasal glioma. d Dural dermal sinus. Linear tract (dotted line) connecting intracranial structures to the dermal opening. Dermoid or epidermoid cysts may form along the dermal sinus tract due to the desquamation of tissue lining the tract