scholarly journals Method for the determination of regional blood flow in tissues by means of stimulated x-ray fluorescence. Final report, January 1, 1969--August 31, 1973

1974 ◽  
Author(s):  
M.M. Ter-Pogossian
2001 ◽  
Vol 40 (02) ◽  
pp. 51-58 ◽  
Author(s):  
H. Schliephake ◽  
van den Hoff ◽  
W. H. Knapp ◽  
G. Berding

Summary Aim: Determination of the range of regional blood flow and fluoride influx during normal incorporation of revascularized fibula grafts used for mandibular reconstruction. Evaluation, if healing complications are preceded by typical deviations of these parameters from the normal range. Assessment of the potential influence of using “scaled population-derived” instead of “individually measured” input functions in quantitative analysis. Methods: Dynamic F-l 8-PET images and arterialized venous blood samples were obtained in 11 patients early and late after surgery. Based on kinetic modeling regional blood flow (K1) and fluoride influx (Kmlf) were determined. Results: In uncomplicated cases, early postoperative graft K1 - but not Kmlf -exceeded that of vertebrae as reference region. Kmn values obtained in graft necrosis (n = 2) were below the ranges of values observed in uncomplicated healing (0.01 13-0.0745 ml/min/ml) as well as that of the reference region (0.0154-0.0748). Knf values in mobile non-union were in the lower range - and those in rigid non-union in the upper range of values obtained in stable union (0.021 1-0.0694). If scaled population-derived instead of measured input functions were used for quantification, mean deviations of 23 ± 17% in K1 and 12 ± 16% in Kmlf were observed. Conclusions: Normal healing of predominantly cortical bone transplants is characterized by relatively low osteoblastic activity together with increased perfusion. It may be anticipated that transplant necrosis can be identified by showing markedly reduced F− influx. In case that measured input functions are not available, quantification with scaled population-derived input functions is appropriate if expected differences in quantitative parameters exceed 70%.


1992 ◽  
Vol 263 (6) ◽  
pp. H1946-H1957 ◽  
Author(s):  
H. Mori ◽  
S. Haruyama ◽  
Y. Shinozaki ◽  
H. Okino ◽  
A. Iida ◽  
...  

We developed new nonradioactive microspheres and used more sensitive X-ray fluorescence spectrometers than used previously to measure regional blood flow in the heart and other organs. We demonstrated the chemical stability of eight kinds of heavy element-loaded microspheres and validated their use for regional blood flow measurement by comparing duplicate flows measured with radioactive and/or nonradioactive microspheres in both acute and chronic dog experiments. The wavelength-dispersive spectrometer (Philips PW 1480) has a higher sensitivity than the previously described X-ray fluorescent system and reduced the number of microspheres required for accurate measurement. The fine energy resolution of this system makes it possible to increase the numbers of different kinds of microspheres to be quantitated, but at present only eight kinds are available. We also used a synchrotron radiation-excited energy dispersive spectrometer. The monochromatic synchrotron radiation allowed us to obtain much higher signal-to-background ratios of X-ray fluorescence spectra than with the wavelength-dispersive system (50 dB more for Zr-loaded microspheres) and will enable analysis of fluorescent activity in smaller regions (< 20 mg) than the radioactive method does.


2001 ◽  
Author(s):  
Anne V. Clough ◽  
Steven T. Haworth ◽  
David T. Roerig ◽  
Christopher C. Hanger ◽  
Christopher A. Dawson

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