title: A preliminary prediction model with MR plaque imaging to estimate risk for new ischemic brain lesions on diffusion-weighted imaging after endarterectomy or stenting in patients with carotid stenosis.
abstract: OBJECTIVE
  Findings on MR imaging of carotid plaques correlate with histologic findings and may be useful in identifying vulnerable plaques. The objective of this study was to show how MR imaging findings and clinical factors could be used to construct a preliminary model and a nomogram for predicting the risk of new ischemic lesions on DWI following CEA or  CAS.
  
  
  METHODS
  One hundred four patients with carotid stenosis undergoing treatment (63 CEA, 41 CAS) were prospectively enrolled (mean age, 71.7 ± 7.0 years; 11 women). T1-SIR and T2-SIR of carotid plaque were measured on MR imaging. Associations among carotid MR imaging findings, treatment procedures, degree of stenosis, cardiovascular risk factors, and occurrence of new ischemic lesions on DWI 1 day after treatment were studied by multivariate logistic  regression.
  
  
  RESULTS
  One stroke occurred after CAS (2.4%), and none after CEA. New DWI lesions after treatment were observed in 25 patients (24%). Our preliminary prediction model demonstrated that T1-SIR (OR [per 0.5 increase], 3.99; 95% CI, 2.18-7.31; P < .0001) and CAS (OR, 2.06; 95% CI, 1.01-4.24; P = .048 compared with CEA) were positively associated with new DWI lesions on posttreatment DWI scans. T2-SIR (OR [per 0.5 increase], 0.74; 95% CI, 0.55-0.98; P = .037) was negatively associated. The C-index of this model was 0.79 (95% CI, 0.69-0.89), which indicated some utility in predicting the  response.
  
  
  CONCLUSIONS
  Our preliminary prediction model and nomogram may provide an individualized risk estimate of new ischemic lesions after CEA or CAS and useful information for decision-making regarding treatment  strategy.
authors.affiliation: Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe,  Japan.
authors.forename: N
authors.initials: N
authors.lastname: Akutsu
authors.forename: K
authors.initials: K
authors.lastname: Hosoda
authors.forename: A
authors.initials: A
authors.lastname: Fujita
authors.forename: E
authors.initials: E
authors.lastname: Kohmura
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000209:etiology*; D002343:Carotid Artery, Internal / Q000473:pathology* / Q000601:surgery; D016893:Carotid Stenosis / Q000473:pathology / Q000601:surgery*; D038524:Diffusion Magnetic Resonance Imaging; D016894:Endarterectomy, Carotid / Q000009:adverse effects; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D015233:Models, Statistical; D049451:Nomograms; D058226:Plaque, Atherosclerotic / Q000175:diagnosis*; D018570:Risk Assessment; D015607:Stents / Q000009:adverse effects