title: The management of midline frontonasal dermoids: a review of 55 cases at a tertiary referral center and a protocol for treatment.
abstract: BACKGROUND
  The incidence of midline frontonasal dermoid cysts is one in 20,000 to one in 40,000. These lesions may have intracranial extension. This is explained by the anatomy and embryology of nasofrontal development. Skin involvement may also be extensive. Incomplete excision frequently leads to recurrence. The authors report their experience and pathway for management of midline dermoids.
  
  
  METHODS
  Databases were searched to identify patients who had undergone surgery for removal of a dermoid cyst. Preoperative imaging and indications for surgery were reviewed. Cases were grouped according to surgical approach, and outcomes and complications were identified.
  
  
  RESULTS
  Fifty-five patients were treated. Magnetic resonance imaging or computed tomography was used to delineate the anatomy, and surgical excision was expedited if there was a history of infection, especially if imaging suggested intracranial extension. Twelve patients were treated endoscopically (one was converted to open). Eleven required transcranial approaches for intracranial extension (20 percent). Of these, one lesion breached the dura. The remaining 32 patients had dermoids excised with an open approach (direct, bicoronal, or rhinoplasty). There were no recurrences in the open group and there was one recurrence in the transcranial group. This was treated by reexcision.
  
  
  CONCLUSIONS
  Midline dermoid cysts are relatively uncommon. However, knowledge of the pathogenesis of these lesions together with the authors' experience over 15 years has allowed them to develop a protocol-driven approach, with a low incidence of complications.
  
  
  METHODS
  Therapeutic, IV.
authors.affiliation: London, United Kingdom From the Craniofacial Unit, Great Ormond Street Hospital for Children.
authors.forename: Mike A
authors.initials: MA
authors.lastname: Moses
authors.forename: Ben C
authors.initials: BC
authors.lastname: Green
authors.forename: Sabrina
authors.initials: S
authors.lastname: Cugno
authors.forename: Richard D
authors.initials: RD
authors.lastname: Hayward
authors.forename: Noor U Owase
authors.initials: NUO
authors.lastname: Jeelani
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Britto
authors.forename: Neil W
authors.initials: NW
authors.lastname: Bulstrode
authors.forename: David J
authors.initials: DJ
authors.lastname: Dunaway
mesh_terms: D000293:Adolescent; D002985:Clinical Protocols; D003884:Dermoid Cyst / Q000175:diagnosis* / Q000601:surgery*; D005153:Facial Neoplasms / Q000601:surgery*; D005260:Female; D005546:Forehead; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009669:Nose Neoplasms / Q000601:surgery*; D062606:Tertiary Care Centers; D014057:Tomography, X-Ray Computed