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(Stroke. 2003;34:e239.)
© 2003 American Heart Association, Inc.

Letters to the Editor

Assessment of Cerebral Blood Flow by Means of Blood-Flow-Volume Measurement

Neurochirurgische Klinik, Medizinische Hochschule Hannover, Hannover, Germany

To the Editor:

With great interest we read in Stroke that a working group around Soustiel¹ compared cerebral blood flow (CBF) as measured by ¹³³xenon clearance technique with blood-flow-volume (BFV) measurements from the internal carotid artery (ICA). Soustiel et al found well-correlated data, ie, correlation coefficients >0.75, in a total of 77 measurements. As a conclusion, the quality of correlations as well as practicability of the new BFV measuring method were emphasized.

In Figures 2 and 3, the results of regression analyses of Xe133 CBF and ICA BFV values are shown. The correlation coefficients of the ipsilateral and global measurements are promising; however, when calculating the coefficient of determination r, only 58% and 70% of data analyzed take part in the correlation, respectively. We speculate the individual error in Xe133 CBF estimation being large.

The main statement of this article seems to be that Xe133 CBF and ICA BFV are proportional. This is not a surprise when measuring these variables because they are naturally related, especially in the global case. Thus, the marked statistical significance of correlation coefficients could be expected. The main criticism, however, is the missing error estimation. Correlations were characterized being "accurate," but to what extent? The knowledge of confidence intervals of regression would relate the authors’ impression of accuracy in the individual case.

References

1. Soustiel JF, Glenn TC, Vespa P, Rinsky B, Hanuscin C, Martin NA. Assessment of cerebral blood flow by means of blood-flow-volume measurement in the internal carotid artery: comparative study with a ¹³³xenon clearance technique. Stroke. 2003; 34: 1876–1880[Abstract/Free Full Text]

This Article Extract Full Text (PDF) All Versions of this Article: 34/12/e239    most recent 01.STR.0000102418.50115.05v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Heissler, H. E. Articles by Rickels, E. Search for Related Content PubMed PubMed Citation Articles by Heissler, H. E. Articles by Rickels, E.