title: Early ischaemic diffusion lesion reduction in patients treated with intravenous tissue plasminogen activator: infrequent, but significantly associated with recanalization.
abstract: OBJECTIVE
  Recent studies have shown that thrombolysis could decrease or eliminate ischaemic diffusion-weighted imaging lesions. However, the features of such diffusion-weighted imaging lesion reduction are not well known.
  
  
  OBJECTIVE
  To clarify, the frequency of and factors associated with lesion reduction were investigated.
  
  
  METHODS
  Patients given intravenous tissue plasminogen activator therapy within three-hours of onset were prospectively enrolled. Magnetic resonance imaging including diffusion-weighted imaging and magnetic resonance angiography was performed four times: on admission, just after intravenous tissue plasminogen activator, 24 h from intravenous tissue plasminogen activator, and seven-days after intravenous tissue plasminogen activator. The diffusion-weighted imaging lesion volume was measured by manual trace using National Institutes of Health imaging software. All patients were divided into three groups according to the early diffusion-weighted imaging lesion volume change from admission to just after intravenous tissue plasminogen activator: the lesion reduction group (>20% decrease); the lesion growth group (>20% increase); and the lesion unchanged group.
  
  
  RESULTS
  In total, 105 patients [56 males, median age 77 (interquartile range 70-83) years, and National Institutes of Health Stroke Scale score 16 (10-22)] were enrolled. Early diffusion-weighted imaging lesion reduction was observed in seven (7%) patients. The decreased lesion increased subsequently. On multivariate analysis, the glucose level on admission (odds ratio 0·95, 95% confidence interval 0·91 to 0·99, P = 0·045) and early recanalization (odds ratio 15·7, 95% confidence interval 1·61 to 153, P = 0·018) were independently related to early lesion reduction.
  
  
  CONCLUSIONS
  Early diffusion-weighted imaging lesion reduction was observed in 7% of patients treated with intravenous tissue plasminogen activator. The decreased lesion increased subsequently. Initial glucose level and early recanalization were independently associated with early diffusion-weighted imaging lesion reduction.
authors.affiliation: Department of Stroke Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki City, Okayama, Japan. ysakamoto02@gmail.com
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sakamoto
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kimura
authors.forename: Kensaku
authors.initials: K
authors.lastname: Shibazaki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Inoue
authors.forename: Jyunichi
authors.initials: J
authors.lastname: Uemura
authors.forename: Junya
authors.initials: J
authors.lastname: Aoki
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Sakai
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Iguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D006801:Humans; D007511:Ischemia / Q000188:drug therapy* / Q000473:pathology*; D018810:Magnetic Resonance Angiography; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator