title: Sensitivity and specificity of intrathecal fluorescein and white light excitation for detecting intraoperative cerebrospinal fluid leak in endoscopic skull base surgery: a prospective study.
abstract: OBJECTIVE
  The intraoperative detection of CSF leaks during endonasal endoscopic skull base surgery is critical to preventing postoperative CSF leaks. Intrathecal fluorescein (ITF) has been used at varying doses to aid in the detection of intraoperative CSF leaks. However, the sensitivity and specificity of ITF at certain dosages is unknown.
  
  
  METHODS
  A prospective database of all endoscopic endonasal procedures was reviewed. All patients received 25 mg ITF diluted in 10 ml CSF and were pretreated with dexamethasone and Benadryl. Immediately after surgery, the operating surgeon prospectively noted if there was an intraoperative CSF leak and fluorescein was identified. The sensitivity, specificity, and positive and negative predictive power of ITF for detecting intraoperative CSF leak were calculated. Factors correlating with postoperative CSF leak were determined.
  
  
  RESULTS
  Of 419 patients, 35.8% of patients did not show a CSF leak. Fluorescein-tinted CSF (true positive) was noted in 59.7% of patients and 0 false positives were encountered. CSF without fluorescein staining (false negative) was noted in 4.5% of patients. The sensitivity and specificity of ITF were 92.9% and 100%, respectively. The negative and positive predictive values were 88.8% and 100%, respectively. Postoperative CSF leaks only occurred in true positives at a rate of 2.8%.
  
  
  CONCLUSIONS
  ITF is extremely specific and very sensitive for detecting intraoperative CSF leaks. Although false negatives can occur, these patients do not appear to be at risk for postoperative CSF leak. The use of ITF may help surgeons prevent postoperative CSF leaks by intraoperatively detecting and confirming a watertight repair.
authors: Department of Neurosurgery, The University of Texas M.D. Anderson Cancer Center, Houston, Texas; and.
authors: Shaan M
authors: SM
authors: Raza
authors: Departments of Neurosurgery.
authors: Matei A
authors: MA
authors: Banu
authors: Otolaryngology, and.
authors: Angela
authors: A
authors: Donaldson
authors: Departments of Neurosurgery.
authors: Kunal S
authors: KS
authors: Patel
authors: Otolaryngology, and.
authors: Vijay K
authors: VK
authors: Anand
authors: Departments of Neurosurgery.|Otolaryngology, and.|Neurology and Neuroscience, Weill Cornell Medical College, NewYork-Presbyterian Hospital, New York, New York.
authors: Theodore H
authors: TH
authors: Schwartz
mesh_terms: D001927:Brain Diseases / Q000473:pathology / Q000601:surgery*; D065634:Cerebrospinal Fluid Leak / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D019793:Fluorescein; D005456:Fluorescent Dyes; D006801:Humans; D007278:Injections, Spinal; D007431:Intraoperative Complications; D008297:Male; D057605:Natural Orifice Endoscopic Surgery / Q000009:adverse effects*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D019291:Skull Base / Q000601:surgery
chemical_list: D005456:Fluorescent Dyes; D019793:Fluorescein
keywords: ITF = intrathecal fluorescein; NPV = negative predictive value; PPV = positive predictive value; cerebrospinal fluid leak; cranial base; endoscopy; fluorescein; intrathecal; minimally invasive; skull base; surgery