title: Increased Blood Viscosity in Ischemic Stroke Patients with Small Artery Occlusion Measured by an Electromagnetic Spinning Sphere Viscometer.
abstract: OBJECTIVE
  High blood viscosity causes blood stagnation and subsequent pathological thrombotic events, resulting in the development of ischemic stroke. We hypothesize that the contribution of blood viscosity may differ among ischemic stroke subtypes based on specific pathological conditions. We tried to verify this hypothesis by measuring blood viscosity in acute ischemic stroke patients using a newly developed electromagnetic spinning sphere (EMS) viscometer.
  
  
  METHODS
  Measurements in acute ischemic stroke patients were performed 4 times during admission and data were compared with those obtained from 100 healthy outpatient volunteers.
  
  
  RESULTS
  We enrolled 92 patients (cardioembolism: 25, large artery atherosclerosis: 42, and small artery occlusion [SAO]: 25) in this study. Comparisons of blood viscosity between the ischemic stroke subgroups and control group revealed that blood viscosity at the date of admission was significantly higher in the SAO group (5.37 ± 1.11 mPa⋅s) than in the control group (4.66 ± .72 mPa⋅s) (P < .01). Among all subtype groups showing a reduction in blood viscosity after 2 weeks, the SAO group showed the highest and most significant reduction, indicating that SAO patients had the most concentrated blood at the onset.
  
  
  CONCLUSIONS
  Blood viscosity was significantly increased in the SAO group at the date of admission, which indicated the contribution of dehydration to the onset of ischemic stroke. The importance of dehydration needs to be emphasized more in the pathogenesis of SAO. The clinical application of the EMS viscometer is promising for understanding and differentiating the pathogenesis of ischemic stroke.
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan; Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan.
authors: Koji
authors: K
authors: Furukawa
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan. Electronic address: abumiya@med.hokudai.ac.jp.
authors: Takeo
authors: T
authors: Abumiya
authors: Department of Fundamental Engineering, Institute of Industrial Science, The University of Tokyo, Tokyo, Japan.
authors: Keiji
authors: K
authors: Sakai
authors: Department of Fundamental Engineering, Institute of Industrial Science, The University of Tokyo, Tokyo, Japan.
authors: Miki
authors: M
authors: Hirano
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Toshiya
authors: T
authors: Osanai
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Hideo
authors: H
authors: Shichinohe
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Naoki
authors: N
authors: Nakayama
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Ken
authors: K
authors: Kazumata
authors: Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan.
authors: Kazutoshi
authors: K
authors: Hida
authors: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: Kiyohiro
authors: K
authors: Houkin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging; D001809:Blood Viscosity; D002545:Brain Ischemia / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology; D016022:Case-Control Studies; D059345:Cerebral Small Vessel Diseases / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging; D003681:Dehydration / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D055590:Electromagnetic Phenomena; D004867:Equipment Design; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012212:Rheology / Q000295:instrumentation* / Q000379:methods; D012307:Risk Factors; D020521:Stroke / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology; D013997:Time Factors
keywords: Blood viscosity; dehydration; ischemic stroke; pathogenesis; rheology; small artery occlusion