title: Diagnosis of cerebrospinal fluid rhinorrhea: an evidence-based review with recommendations.
abstract: BACKGROUND
  Diagnostic strategies employed for cases of cerebrospinal fluid (CSF) rhinorrhea vary widely due to limited evidence-based guidance.
  
  
  METHODS
  A systematic review of the literature was performed using PubMed, EMBASE, and Cochrane databases from January 1990 through September 2014, to examine 9 diagnostic and localization modalities for CSF rhinorrhea. Benefit-harm assessments, value judgments and recommendations were made based on the available evidence. Study exclusion criteria were language other than English, pre-1990 studies, case reports, and nonrhinologic leak. All authors agreed on recommendations through an iterative process.
  
  
  RESULTS
  We reviewed 68 studies examining 9 practices pertinent to the diagnosis of CSF rhinorrhea, with a highest aggregate grade of evidence of C. The literature does not support the use of the ring sign, glucose testing, radionuclide cisternography (RNC), or computed tomography cisternography (CTC) for identification of CSF leak. Beta-2 transferrin is the most reliable confirmatory test for CSF leak. High-resolution CT (HRCT) is then recommended as the first-line study for localization. Magnetic resonance cisternography (MRC) should be used for CSF leak identification as a second line for each of these if beta-2 transferrin is not available or if HRCT is ambiguous. Intrathecal fluorescein (IF) may also be of benefit in certain clinical scenarios.
  
  
  CONCLUSIONS
  Despite relatively low levels of evidence, recommendations for the diagnosis and management of CSF rhinorrhea can be made based on the current literature. Higher-level studies are needed to better determine optimal diagnostic and clinical management approaches.
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Gretchen M
authors.initials: GM
authors.lastname: Oakley
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Jeremiah A
authors.initials: JA
authors.lastname: Alt
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC.
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Schlosser
authors.affiliation: Faculty of Health Sciences, Macquarie University, Sydney, Australia.|Rhinology and Skull Base Research Group, Applied Medical Research Centre, University of New South Wales, Sydney, Australia.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Harvey
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Richard R
authors.initials: RR
authors.lastname: Orlandi
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002559:Cerebrospinal Fluid Rhinorrhea / Q000175:diagnosis* / Q000378:metabolism; D019793:Fluorescein; D005456:Fluorescent Dyes; D006801:Humans; D008279:Magnetic Resonance Imaging; D014057:Tomography, X-Ray Computed
chemical_list: D015415:Biomarkers; D005456:Fluorescent Dyes; D019793:Fluorescein
keywords: CSF leak; CSF rhinorrhea; cerebrospinal fluid; diagnosis; diagnostic algorithm; localization