title: Capillary Transit Time Heterogeneity Is Associated with Modified Rankin Scale Score at Discharge in Patients with Bilateral High Grade Internal Carotid Artery Stenosis.
abstract: OBJECTIVE
  Perfusion weighted imaging (PWI) is inherently unreliable in patients with severe perfusion abnormalities. We compared the diagnostic accuracy of a novel index of microvascular flow-patterns, so-called capillary transit time heterogeneity (CTH) to that of the commonly used delay parameter Tmax in patients with bilateral high grade internal carotid artery stenosis (ICAS).
  
  
  METHODS
  Consecutive patients with bilateral ICAS ≥ 70%NASCET who underwent PWI were retrospectively examined. Maps of CTH and Tmax were analyzed with a volumetric approach using several thresholds. Predictors of favorable outcome (modified Rankin scale at discharge 0-2) were identified using univariate and receiver operating characteristic (ROC) curve analysis.
  
  
  RESULTS
  Eighteen patients were included. CTH ≥ 30s differentiated best between patients with favorable and unfavorable outcome when both hemispheres were taken into account (sensitivity 83%, specificity 73%, area under the curve [AUC] 0.833 [confidence interval (CI) 0.635; 1.000]; p = 0.027). The best discrimination using Tmax was achieved with a threshold of ≥ 4s (sensitivity 83%, specificity 64%, AUC 0.803 [CI 0.585;1.000]; p = 0.044). The highest AUC was found for left sided volume with CTH ≥ 15s (sensitivity 83%, specificity 91%, AUC 0.924 [CI 0.791;1.000]; p = 0.005).
  
  
  CONCLUSIONS
  The study suggests that CTH is superior to Tmax in discriminating ICAS patients with favorable from non-favorable outcome. This finding may reflect the simultaneous involvement of large vessels and microvessels in ICAS and underscore the need to diagnose and manage both aspects of the disease.
authors.affiliation: Department of Neurology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Sibu
authors.initials: S
authors.lastname: Mundiyanapurath
authors.affiliation: Department of Neurology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Peter Arthur
authors.initials: PA
authors.lastname: Ringleb
authors.affiliation: German Cancer Research Center, Department of Radiology, Heidelberg, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Diatschuk
authors.affiliation: Center of Functionally Integrative Neuroscience and MINDLab, Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Mikkel Bo
authors.initials: MB
authors.lastname: Hansen
authors.affiliation: Center of Functionally Integrative Neuroscience and MINDLab, Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Kim
authors.initials: K
authors.lastname: Mouridsen
authors.affiliation: Center of Functionally Integrative Neuroscience and MINDLab, Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark.|Department of Neuroradiology, Aarhus Univesity Hospital, Aarhus, Denmark.
authors.forename: Leif
authors.initials: L
authors.lastname: Østergaard
authors.affiliation: Department of Neurology, University Hospital Heidelberg, Heidelberg, Germany.|CCU Neurooncology, German Cancer Consortium (DKTK) & German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wick
authors.affiliation: Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Bendszus
authors.affiliation: German Cancer Research Center, Department of Radiology, Heidelberg, Germany.|Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Radbruch
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D002343:Carotid Artery, Internal / Q000473:pathology* / Q000503:physiopathology*; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D055420:Perfusion Imaging / Q000379:methods*; D012372:ROC Curve; D012039:Regional Blood Flow; D012307:Risk Factors