title: Collateral circulation on perfusion-computed tomography-source images predicts the response to stroke intravenous thrombolysis.
abstract: OBJECTIVE
  Perfusion-computed tomography-source images (PCT-SI) may allow a dynamic assessment of leptomeningeal collateral arteries (LMC) filling and emptying in middle cerebral artery (MCA) ischaemic stroke. We described a regional LMC scale on PCT-SI and hypothesized that a higher collateral score would predict a better response to intravenous (iv) thrombolysis.
  
  
  METHODS
  We studied consecutive ischaemic stroke patients with an acute MCA occlusion documented by transcranial Doppler/transcranial color-coded duplex, treated with iv thrombolysis who underwent PCT prior to treatment. Readers evaluated PCT-SI in a blinded fashion to assess LMC within the hypoperfused MCA territory. LMC scored as follows: 0, absence of vessels; 1, collateral supply filling ≤ 50%; 2, between> 50% and < 100%; 3, equal or more prominent when compared with the unaffected hemisphere. The scale was divided into good (scores 2-3) vs. poor (scores 0-1) collaterals. The predetermined primary end-point was a good 3-month functional outcome, while early neurological recovery, transcranial duplex-assessed 24-h MCA recanalization, 24-h hypodensity volume and hemorrhagic transformation were considered secondary end-points.
  
  
  RESULTS
  Fifty-four patients were included (55.5% women, median NIHSS 10), and 4-13-23-14 patients had LMC score (LMCs) of 0-1-2-3, respectively. The probability of a good long-term outcome augmented gradually with increasing LMCs: (0) 0%; (1) 15.4%; (2) 65.2%; (3) 64.3%, P = 0.004. Good-LMCs was independently associated with a good outcome [OR 21.02 (95% CI 2.23-197.75), P = 0.008]. Patients with good LMCs had better early neurological recovery (P = 0.001), smaller hypodensity volumes (P < 0.001) and a clear trend towards a higher recanalization rate.
  
  
  CONCLUSIONS
  A higher degree of LMC assessed by PCT-SI predicts good response to iv thrombolysis in MCA ischaemic stroke patients.
authors.affiliation: Stroke Unit, Department of Neurology, Hospital Clínico Universitario, Valladolid, Spain. aicsanz@hotmail.com
authors.forename: A I
authors.initials: AI
authors.lastname: Calleja
authors.forename: E
authors.initials: E
authors.lastname: Cortijo
authors.forename: P
authors.initials: P
authors.lastname: García-Bermejo
authors.forename: R D
authors.initials: RD
authors.lastname: Gómez
authors.forename: S
authors.initials: S
authors.lastname: Pérez-Fernández
authors.forename: J M
authors.initials: JM
authors.lastname: Del Monte
authors.forename: M F
authors.initials: MF
authors.lastname: Muñoz
authors.forename: R
authors.initials: R
authors.lastname: Fernández-Herranz
authors.forename: J F
authors.initials: JF
authors.lastname: Arenillas
mesh_terms: D061605:Administration, Intravenous; D000368:Aged; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology*; D003097:Collateral Circulation / Q000502:physiology*; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D055420:Perfusion Imaging; D011446:Prospective Studies; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage / Q000627:therapeutic use*; D014463:Ultrasonography
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator