Cerebral Perfusion Associated With Postural Changes: an ASL MR Perfusion Study "PerfIRMAVC"

Recruiting

Phase N/A Results N/A

Trial Description

Postural changes are commonly used as therapeutic maneuver to enhance or reduce cerebral perfusion. For instance, in acute stroke, the patient can be positioned in head down tilt position so as to increase perfusion of cerebral tissues perfusion. In During stroke and in hypertensive patients and during stroke, varying degrees a various loss of cerebral autoregulation is loss are usually observed. The aim of this study is to assess cerebral perfusion with ASL perfusion in human subjects in different conditions: healthy, hypertensive and stroke.

Detailed Description

Material and methods:
Eighteen stroke patients, eighteen hypertensive patients and eighteen healthy subjects (men and women) will be enrolled. The investigator will use a 1.5 Tesla MRI device with a large magnet bore (70 cm) allowing positions change. Two measures will be performed, one in supine position and the other in head down position (-20°). A 3D FSE ASL sequence will be acquired and Cerebral Blood Flow (CBF) maps will be reconstructed. Volume of interest (VOI) will be placed on cortical grey matter (frontal and posterior gyrus), on subcortical deep grey matter (caudate nuclei, thalami) and subcortical white matter (semi oval centers). Differences in CBF values (in mL/100g/min) will be analyzed using SAS 9.3 software for Windows (SAS Institute, Cary North Carolina, USA).
Expected results and hypothesis:
CBF is expected to significantly vary between the supine and head down positions. It is expected to at least increase in the head down position, for stroke patients. For healthy subjects and hypertensive patients, cerebral autoregulation may limit CBF increase although an increasing trend for CBF is expected.

Conditions

Interventions

  • MRI Device
    Intervention Desc: A 1.5 Tesla MRI device with a large magnet bore (70 cm) allowing positions change will be used. Two measures will be performed, one in supine position and the other in head down position (-20°). A 3D FSE ASL sequence will be acquired and CBF maps reconstructed. Volume of interest (VOI) will be placed on cortical grey matter (frontal and posterior gyrus), on subcortical deep grey matter (caudate nuclei, thalami) and subcortical white matter (semi oval centers
    ARM 1: Kind: Experimental
    Label: Control group
    Description: Eighteen healthy subjects and eighteen hypertensive patients (men and women) will be enrolled. A 1.5 Tesla MRI device with a large magnet bore (70 cm) will be used, allowing positions change. Two measures will be performed, one in supine position and the other in head down position (-20°). A 3D FSE ASL sequence will be acquired and Cerebral Blood Flow (CBF) maps will be reconstructed. Volume of interest (VOI) will be placed on cortical grey matter (frontal and posterior gyrus), on subcortical deep grey matter (caudate nuclei, thalami) and subcortical white matter (semi oval centers). Differences in CBF values (in mL/100g/min) will be analyzed using SAS 9.3 software for Windows (SAS Institute, Cary North Carolina, USA).
    ARM 2: Kind: Experimental
    Label: Stroke patients
    Description: Eighteen stroke patients (men and women) will be enrolled. A 1.5 Tesla MRI device with a large magnet bore (70 cm) will be used, allowing positions change. Two measures will be performed, one in supine position and the other in head down position (-20°). A 3D FSE ASL sequence will be acquired and Cerebral Blood Flow (CBF) maps will be reconstructed. Volume of interest (VOI) will be placed on cortical grey matter (frontal and posterior gyrus), on subcortical deep grey matter (caudate nuclei, thalami) and subcortical white matter (semi oval centers). Differences in CBF values (in mL/100g/min) will be analyzed using SAS 9.3 software for Windows (SAS Institute, Cary North Carolina, USA).

Trial Design

  • Allocation: Non-Randomized
  • Masking: Open Label
  • Endpoint: Efficacy Study
  • Intervention: Factorial Assignment

Outcomes

Type Measure Time Frame Safety Issue
Primary The change in the value of the cerebral blood flow up to 1 year No

Sponsors