title: Correlation between angiographic transit times and neurological status on admission in patients with aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  The use of digital subtraction angiography (DSA) for semiquantitative cerebral blood flow(CBF) assessment is a new technique. The aim of this study was to determine whether patients with aneurysmal subarachnoid hemorrhage (aSAH) with higher Hunt and Hess grades also had higher angiographic contrast transit times (TTs) than patients with lower grades.
  
  
  METHODS
  A cohort of 30 patients with aSAH and 10 patients without aSAH was included. Relevant clinical information was collected. A method to measure DSA TTs by color-coding reconstructions from DSA contrast-intensity images was applied. Regions of interest (ROIs) were chosen over major cerebral vessels. The estimated TTs included time-to-peak from 0% to 100% (TTP0-100), TTP from 25% to 100% (TTP25-100), and TT from 100% to 10% (TT100-10) contrast intensities. Statistical analysis was used to compare TTs between Group A (Hunt and Hess Grade I-II), Group B (Hunt and Hess Grade III-IV), and the control group. The correlation coefficient was calculated between different ROIs in aSAH groups.
  
  
  RESULTS
  There was no difference in demographic factors between Group A (n = 10), Group B (n = 20), and the control group (n = 10). There was a strong correlation in all TTs between ROIs in the middle cerebral artery (M1, M2) and anterior cerebral artery (A1, A2). There was a statistically significant difference between Groups A and B in all TT parameters for ROIs. TT100-10 values in the control group were significantly lower than the values in Group B.
  
  
  CONCLUSIONS
  The DSA TTs showed significant correlation with Hunt and Hess grades. TT delays appear to be independent of increased intracranial pressure and may be an indicator of decreased CBF in patients with a higher Hunt and Hess grade. This method may serve as an indirect technique to assess relative CBF in the angiography suite.
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Alexander
authors.initials: A
authors.lastname: Ivanov
authors.affiliation: Departments of 1 Neurosurgery and.|Bioengineering, University of Illinois at Chicago, Illinois.
authors.forename: Andreas
authors.initials: A
authors.lastname: Linninger
authors.affiliation: Bioengineering, University of Illinois at Chicago, Illinois.
authors.forename: Chih-Yang
authors.initials: CY
authors.lastname: Hsu
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Sepideh
authors.initials: S
authors.lastname: Amin-Hanjani
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Victor A
authors.initials: VA
authors.lastname: Aletich
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Fady T
authors.initials: FT
authors.lastname: Charbel
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Ali
authors.initials: A
authors.lastname: Alaraj
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D015331:Cohort Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007427:Intracranial Pressure; D008297:Male; D008875:Middle Aged; D013345:Subarachnoid Hemorrhage / Q000503:physiopathology* / Q000523:psychology*; D016896:Treatment Outcome
keywords: CBF = cerebral blood flow; DICOM = Digital Imaging and Communications in Medicine; DSA = digital subtraction angiography; EVD = external ventricular drain; GOS = Glasgow Outcome Scale; Hunt and Hess; ICA = internal carotid artery; ICP = intracranial pressure; ROI = region of interest; TT = transit time; TTP = time-to-peak; aSAH = aneurysmal subarachnoid hemorrhage; digital subtraction angiography; mRS = modified Rankin Scale; neurological outcome; subarachnoid hemorrhage; transit times; vascular disorders