title: Evolution of computed tomography angiography spot sign is consistent with a site of active hemorrhage in acute intracerebral hemorrhage.
abstract: OBJECTIVE
  CT angiography spot sign predicts hematoma expansion in patients with acute intracerebral hemorrhage (ICH). The spot sign may represent a site of active extravasation, a locus of arrested hemorrhage forming fibrin globes, or represent associated epiphenomena such as hypertensive microaneurysms. We sought to describe the evolution of spot signs over 60 seconds in acute ICH using dynamic CT angiography and determine whether they grow and diffuse into the hematoma as would be expected with active extravasation.
  
  
  METHODS
  We prospectively identified consecutive patients presenting with spontaneous ICH<6 hours from symptom onset that completed dynamic CT angiography imaging over a 60-second acquisition protocol. We determined spot positivity, quantified spot volumes, and then used repeated-measures ANOVA to assess changes in spot volume over time.
  
  
  RESULTS
  We collected data on 35 patients; 13 of 35 (37%) patients were spot-positive. Spot-positive patients had larger median ICH volume compared with spot-negative patients (median 10.7 versus 49.2 mL; P=0.007). Maximal spot sign volumes ranged from 0.02 to 2.8 mL (median 0.17 mL). Spot sign volumes increased significantly with time (P<0.001) and seemed to disperse into the hematoma in all cases. Three of 13 (23%) spot-positive patients presented with 2 distinct spot signs, but the remaining patients either had only 1 spot sign or different contiguous components of an irregularly shaped spot sign.
  
  
  CONCLUSIONS
  In this dynamic CT angiography study of ICH, spot signs evolve consistent with sites of active extravasation.
authors.affiliation: From the Departments of Medicine-Neurology (D.D., G.S., M.H.), Pathology and Laboratory Medicine (J.K.W.), Epidemiology and Community Medicine (D.D., F.M.), Clinical Epidemiology (F.M.), Methods Centre (F.M., W.P.), and Medical Imaging-Neuroradiology (S.C.), University of Ottawa, CHEO Research Institute (F.M.) and Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Medicine, McMaster University, Population Health Research Institute, Hamilton, Ontario, Canada (M.S.); Department of Medical Imaging (Neuroradiology), Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada (R.I.A.); and Departments of Clinical Neurosciences and Radiology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada (A.M.D.).
authors.forename: Dar
authors.initials: D
authors.lastname: Dowlatshahi
authors.forename: Jason K
authors.initials: JK
authors.lastname: Wasserman
authors.forename: Franco
authors.initials: F
authors.lastname: Momoli
authors.forename: William
authors.initials: W
authors.lastname: Petrcich
authors.forename: Grant
authors.initials: G
authors.lastname: Stotts
authors.forename: Matthew
authors.initials: M
authors.lastname: Hogan
authors.forename: Mukul
authors.initials: M
authors.lastname: Sharma
authors.forename: Richard I
authors.initials: RI
authors.lastname: Aviv
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
authors.forename: Santanu
authors.initials: S
authors.lastname: Chakraborty
mesh_terms: D000208:Acute Disease; D000704:Analysis of Variance; D002533:Cerebral Angiography / Q000379:methods*; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D018450:Disease Progression; D006801:Humans; D007091:Image Processing, Computer-Assisted; D011446:Prospective Studies; D015203:Reproducibility of Results; D020521:Stroke / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: cerebral hemorrhage; computerized tomography; contrast agent; hematoma