[Methods for measuring spinal cord blood flow].
This study aimed to review the techniques used most currently for measuring spinal cord blood blow flow (SCBF) in animals, i.e. the hydrogen clearance, labelled microspheres, 133Xe clearance and 14C-antipyrine autoradiographic methods. All four techniques may only be used in animals, because of their invasiveness. Flow figures varied greatly with the method, the spinal level at which measurements were carried out, and the species of animal. However, results tend to suggest that SCBF is very similar to cerebral blood flow in that it is controlled by chemical, autoregulatory and metabolic factors. Approaches to measuring SCBF in man may be made using stable xenon-enhanced computed tomographic imaging (Xes-CT) in the same way as for measuring cerebral blood flow. The calculation of SCBF is based on Fick's principle transformed by Kety and Schmidt. After a reference CT section has been obtained, twelve 8 mm thick sections are carried out whilst the patient breathes a 30% xenon-70% air/oxygen mixture. This series of views enables the SCBF to be calculated in four steps. Quantitative analysis in eight human subjects gave a mean SCBF of 58.8 +/- 5.96 ml x 100 g-1 x min-1. However, this method has a low signal to noise ratio. Moreover, the qualitative analysis of the parametric views of flow demonstrate tissue heterogeneity, partly due to the patient's movements (breathing movements). However, the method is non invasive, safe, and reproducible. As it can measure very low values of blood flow, the study of ischaemic spinal lesions is made possible, although some technical and software improvements are still required.
Bidabé
A M
AM
Service de Neuroradiologie, CHR de Bordeaux.
Gin
A M
AM
Pointillart
V
V
Gense de Beaufort
D
D
Sesay
M
M
Caille
J M
JM
D000328:Adult; D000818:Animals; D001345:Autoradiography; D005260:Female; D006801:Humans; D006859:Hydrogen / Q000493:pharmacokinetics; D008297:Male; D008657:Metabolic Clearance Rate; D012039:Regional Blood Flow; D013116:Spinal Cord / Q000098:blood supply* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014978:Xenon / Q000493:pharmacokinetics
D014978:Xenon; D006859:Hydrogen
Méthodes de mesure du débit sanguin médullaire.