HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JNM Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Herrero, P. Articles by Welch, M. J. Search for Related Content PubMed PubMed Citation Articles by Herrero, P. Articles by Welch, M. J.

Assessment of Myocardial Blood Flow Using ¹⁵O-Water and 1-¹¹C-Acetate in Rats with Small-Animal PET

Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri

Correspondence: For correspondence contact: Pilar Herrero, MS, Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8225, 510 S. Kingshighway Blvd., St. Louis, MO 63110. E-mail: herrerop{at}mir.wustl.edu

This feasibility study was undertaken to determine whether myocardial blood flow (MBF, mL/g/min) could be quantified noninvasively in small rodents using microPET and ¹⁵O-water or 1-¹¹C-acetate. Methods: MBF was measured in 18 healthy rats using PET and ¹⁵O-water (MBF-W) under different interventions and compared with direct measurements obtained with microspheres (MBF-M). Subsequently, MBF was estimated in 24 rats at rest using 1-¹¹C-acetate (MBF-Ace) and compared with measurements obtained with ¹⁵O-water. Using factor analysis, images were processed to obtain 1 blood and 1 myocardial time–activity curve per tracer per study. MBF-W was calculated using a well-validated 1-compartment kinetic model. MBF-Ace was estimated using a simple 1-compartment model to estimate net tracer uptake, K₁ (K₁ (mL/g/min) = MBF·E; E = first-pass myocardial extraction of 1-¹¹C-acetate) and washout (k₂ (min^–1)) along with F_BM (spillover correction) after fixing F_MM (partial-volume correction) to values obtained from ¹⁵O-water modeling. K₁ values were converted to MBF values using a first-pass myocardial extraction/flow relationship measured in rats (E = 1.0–0.74·exp(–1.13/MBF)). Results: In the first study, MBF-W correlated well with MBF-M (y = 0.74x + 0.96; n = 18, r = 0.91, P < 0.0001). However, the slope was different than unity, P < 0.05). Refitting of the data after forcing the intercept to be zero resulted in a nonbias correlation between MBF-W and MBF-M (y = 0.95x + 0.0; n = 18, r = 0.86, P < 0.0001) demonstrating that the underestimation of the slope could be attributed to the overestimation of MBF-W for 2 MBF-M values lower than 1.50 mL/g/min. In the second study, MBF-Ace values correlated well with MBF-W with no underestimation of MBF (y = 0.91x + 0.35; n = 24, r = 0.87, P < 0.0001). Conclusion: MBF can be quantified by PET using ¹⁵O-water or 1-¹¹C-acetate in healthy rats. Future studies are needed to determine the accuracy of the methods in low-flow states and to develop an approach for a partial-volume correction when 1-¹¹C-acetate is used.

Key Words: small-animal PET • myocardial blood flow • ¹⁵O-water • 1-¹¹C-acetate

Related articles in JNM:

This Month in JNM

JNM 2006 47: 7a-8a. [Full Text]  

This article has been cited by other articles:

				K. I. Shoghi, R. J. Gropler, T. Sharp, P. Herrero, N. Fettig, Y. Su, M. S. Mitra, A. Kovacs, B. N. Finck, and M. J. Welch Time Course of Alterations in Myocardial Glucose Utilization in the Zucker Diabetic Fatty Rat with Correlation to Gene Expression of Glucose Transporters: A Small-Animal PET Investigation J. Nucl. Med., August 1, 2008; 49(8): 1320 - 1327. [Abstract] [Full Text] [PDF]

				M. C. Huisman, T. Higuchi, S. Reder, S. G. Nekolla, T. Poethko, H.-J. Wester, S. I. Ziegler, D. S. Casebier, S. P. Robinson, and M. Schwaiger Initial Characterization of an 18F-Labeled Myocardial Perfusion Tracer J. Nucl. Med., April 1, 2008; 49(4): 630 - 636. [Abstract] [Full Text] [PDF]

				M. J. Welch, J. S. Lewis, J. Kim, T. L. Sharp, C. S. Dence, R. J. Gropler, and P. Herrero Assessment of Myocardial Metabolism in Diabetic Rats Using Small-Animal PET: A Feasibility Study J. Nucl. Med., April 1, 2006; 47(4): 689 - 697. [Abstract] [Full Text] [PDF]