title: The Sonographic Stenosis Index: A New Specific Quantitative Measure of Transplant Hepatic Arterial Stenosis.
abstract: OBJECTIVE
  This study evaluates the sensitivity and specificity of stenosis index (SI), which accounts for the entire spectral Doppler waveform, to detect significant transplant hepatic arterial stenosis.
  
  
  METHODS
  In this institutional review board-approved, HIPAA compliant study, we retrospectively analyzed 69 patients who had catheter angiography for suspected transplant hepatic arterial stenosis (THAS) between January 2006 and December 2010; all patients had Doppler ultrasound within 30 days before angiography. Patients with angiographic stenosis requiring intervention were considered positive for THAS. Stenosis index was calculated from each patient's spectral Doppler ultrasound images by obtaining the ratio of the area under the high-frequency signal to low-frequency signal in the spectral Doppler. Resistive index (RI) and pulsatility index (PI) were also calculated. Receiver operator curve analysis was performed and the area under the curve (AUC) was compared among the three metrics.
  
  
  RESULTS
  Forty-eight of 69 patients had THAS by angiography requiring intervention; 21patients had no angiographic evidence of THAS. SI was significantly different (P < .001) between patients with THAS (SI = 1.04 ± 0.20) and those without THAS (SI = 1.39 ± 0.30). Stenosis index had an AUC of 0.86 for detecting THAS, which was significantly higher than that from RI (AUC = 0.68, P = .038 for the comparison) and PI (AUC = 0.70, P = .029). For SI < 1.35, the sensitivity for THAS was 94% and specificity was 52%. For RI < 0.5, the sensitivity was 96% and the specificity was 29%.
  
  
  CONCLUSIONS
  Stenosis index is more accurate than the resistive index and the pulsatility index for detecting transplant hepatic artery stenosis.
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.|Olive View-UCLA Medical Center, Sylmar, California, USA.
authors.forename: Thomas X
authors.initials: TX
authors.lastname: Le
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Hippe
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.
authors.forename: Michael F
authors.initials: MF
authors.lastname: McNeeley
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.
authors.forename: Manjiri K
authors.initials: MK
authors.lastname: Dighe
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.
authors.forename: Theodore J
authors.initials: TJ
authors.lastname: Dubinsky
authors.affiliation: University of Washington School of Medicine, Department of Radiology, Seattle, Washington, USA.|Children's Mercy Hospital, Kansas City, Missouri, USA.
authors.forename: Sherwin S
authors.initials: SS
authors.lastname: Chan
mesh_terms: D000328:Adult; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler / Q000379:methods*
keywords: arterial stenosis; general; liver transplant; spectral Doppler vascular ultrasound