title: Rhinolithiasis: clinical, radiological, and mineralogical features.
abstract: BACKGROUND
  Rhinolithiasis is a rare and under-diagnosed clinical entity whose etiology and pathogenesis is poorly understood.
  
  
  OBJECTIVE
  The objective of the study is to review the clinical and radiologic features of rhinolithiasis and mineralogical-chemical composition of the rhinoliths with the aim of shedding light on its etiology and pathogenesis.
  
  
  METHODS
  Our subjects consisted of 8 rhinolithiasis cases. Clinical presentations, signs, and symptoms of the patients with radiologic findings are presented, and X-ray diffraction analyses of the stones were carried out to assess their mineralogical composition.
  
  
  RESULTS
  Nasal obstruction appeared to be the chief symptom, followed by nasal discharge and facial pain. Neither exogenous nor endogenous nidi were identified in any of the cases. Mineralogical analyses of the rhinoliths revealed Whitlockite [(Ca,Mg)3 (PO4)2] in one and Dahllite [Ca5 (PO4,CO3)3OH] in 7 cases.
  
  
  CONCLUSIONS
  We hypothesized that some substances or organic objects form the nidi of the rhinoliths and are disintegrated over the course of mineral precipitation. This hypothesis was supported by radiologic and microscopic findings.
authors.affiliation: Department of Otolaryngology, Yuzuncuyil University Medical Faculty, Van, Turkey. nadir_yildirim@yahoo.com
authors.forename: Nadir
authors.initials: N
authors.lastname: Yildirim
authors.forename: Atilla
authors.initials: A
authors.lastname: Arslanoglu
authors.forename: Murat
authors.initials: M
authors.lastname: Sahan
authors.forename: Altan
authors.initials: A
authors.lastname: Yildirim
mesh_terms: D000293:Adolescent; D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020347:Lithiasis / Q000737:chemistry / Q000150:complications* / Q000000981:diagnostic imaging; D008297:Male; D008903:Minerals / Q000032:analysis*; D015508:Nasal Obstruction / Q000000981:diagnostic imaging / Q000209:etiology* / Q000378:metabolism; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging*; D011379:Prognosis; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D008903:Minerals