title: Carotid artery stenosis at MSCT: is there a threshold in millimeters that determines clinical significance?
abstract: OBJECTIVE
  The purpose of this work was to determine whether it is possible to identify a reliable carotid stenosis threshold--measured in millimeters (mm)--that is associated with cerebrovascular symptoms.
  
  
  METHODS
  Written, informed consent was obtained for each patient; 149 consecutive patients (98 men; median age, 68 years) were studied for suspected pathology of the carotid arteries by using MDCTA. In each patient, carotid artery stenosis was quantified using the mm-method. Continuous data were described as the mean value ± standard deviation (SD), and they were compared by using the Student's t test. A ROC curve was calculated to test the study hypothesis and identify a specific mm-stenosis threshold. Logistic regression analysis was performed to include other MDCTA findings, such as plaque type and ulcerations. A P value < 0.05 was considered to indicate statistical significance.
  
  
  RESULTS
  Twenty-six patients were excluded. Of those remaining, 75 patients suffered cerebrovascular symptoms (61%). There was a statistically significant difference (P = 0.0046) in the mm-carotid stenosis between patients with symptoms (1.31 ± 0.64 mm SD) and without symptoms (1.68 ± 0.79 mm SD). Multiple logistic regression analysis confirmed that symptoms were associated with increased luminal stenosis (P = 0.013) and with the presence of fatty plaques (P = 0.0491). Moreover, the ROC curve (Az = 0.669; ±0.051 SD; P = 0.0009) indicated that a threshold of 1.6 mm stenosis was associated with a sensitivity to symptoms of 76%.
  
  
  CONCLUSIONS
  The results of our study suggest an association between luminal stenosis (measure in mm) and the presence of cerebrovascular symptoms. Luminal stenosis of 1.6 mm is associated, with a sensitivity of 76%, with cerebrovascular symptoms.
authors.affiliation: Department of Radiology, Azienda Ospedaliero Universitaria, di Cagliari-Polo di Monserrato, s.s. 554, 09045 Monserrato, CA, Italy. lucasaba@tiscali.it
authors.forename: Luca
authors.initials: L
authors.lastname: Saba
authors.forename: Roberto
authors.initials: R
authors.lastname: Sanfilippo
authors.forename: Roberto
authors.initials: R
authors.lastname: Montisci
authors.forename: Giorgio
authors.initials: G
authors.lastname: Mallarini
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology; D003287:Contrast Media; D005260:Female; D006801:Humans; D007479:Iopamidol / Q000031:analogs & derivatives; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol