title: The difference in anatomical and invasive characteristics between primary and secondary paranasal sinus mucoceles.
abstract: OBJECTIVE
  To evaluate the difference in anatomical and invasive characteristics of primary and secondary paranasal sinus mucoceles.
  
  
  METHODS
  A retrospective chart review at a tertiary academic center.
  
  
  RESULTS
  During a 10-year period, 57 and 109 patients with primary and secondary mucoceles were enrolled, respectively. Thirty-five (61.4%) of primary and 26 (23.9%) of secondary mucoceles had intraorbital extension (IOE), while seven (12.3%) of primary and two (1.8%) of secondary mucoceles had intracranial extension (ICE). In comparison of tendency for IOE or ICE between primary and secondary mucoceles in each sinus, only primary maxillary mucoceles were shown to have a significantly higher probability of IOE than secondary maxillary mucoceles. Among primary mucoceles, ethmoid mucoceles had a significantly greater capability to cause IOE while maxillary mucoceles had the least. Among secondary mucoceles, frontal and ethmoid mucoceles had a greater ability to cause IOE while maxillary mucoceles had the least. As for ICE, sphenoid mucoceles had a greater potential in both groups.
  
  
  CONCLUSIONS
  Primary mucoceles seem to have a greater potential to cause IOE and ICE than secondary mucoceles. In both groups, ethmoid mucoceles have a higher potential of IOE, while sphenoid mucoceles have a greater tendency to cause ICE.
authors.affiliation: Department of Otolaryngology, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan.
authors.forename: Chia-Hsiang
authors.initials: CH
authors.lastname: Fu
authors.forename: Kai-Ping
authors.initials: KP
authors.lastname: Chang
authors.forename: Ta-Jen
authors.initials: TJ
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009078:Mucocele / Q000209:etiology / Q000473:pathology*; D010254:Paranasal Sinus Diseases / Q000209:etiology / Q000473:pathology*; D012189:Retrospective Studies