Validation of fluorescent microsphere technique for measurement of
organ perfusion with simplified sample processing method.
Prinzen, Eman Md Phd; Frits W., Phd.
Departments of Physiology and Anesthesiology, Cardiovascular
Research Institute Maastricht, University of Limburg, Maastricht, The
Netherlands
APStracts 2:0069H, 1995.
A disadvantage of non-radioactive microsphere techniques is that the
processing of samples is time consuming and complex. We developed and
validated a simplified processing method for the fluorescent
microsphere (FM) technique. In 7 anesthetized dogs with coronary
artery stenosis up to 6 different FM and 5 different radioactively
labeled microspheres (RM) were injected, 2 FM and 2 RM labels being
injected simultaneously to enable inter and intra-method comparison.
After gamma counting samples of blood, myocardium (n=168) and other
organs (n=59) were digested in test tubes using ethanolic KOH 2N
(60[acute]iC, 48 hour), microspheres were sedimentated by
centrifugation and dye was extracted in the same tube followed by
fluorescence measurement. Using this processing method recovery of FM
was nearly 100%. Good correlations for inter- and intra-method
comparisons were found, r was 0.985 0.01 (mean s.d.), the lower
inter-method correlation for blue microspheres (r=0.958) indicate
that the use of this label is less desirable. Also RM and FM
endo/epicardial blood flow ratios correlated well (r=0.974). Using
this one vessel centrifugal sedimentation method and at least 5
fluorescently labeled microspheres, blood flow can be reliably
measured in various organs, including ischemic myocardium.
Received 3 November 1994; accepted in final form 24 February
1995.
APS Manuscript Number H982-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 March 1995.