caa a22 4500 465784941 CHVBK 20180323112006.0 cr unu---uuuuu 170327e19900101xx s 000 0 eng 10.1007/BF00819407 doi (NATIONALLICENCE)springer-10.1007/BF00819407 In vitro validation of a simple tomographic technique for estimation of percentage myocardium at risk using methoxyisobutyl isonitrile technetium 99m (sestamibi) [Elektronische Daten] [Michael O'Connor, Thomas Hammell, Raymond Gibbons] With the advent of technetium 99m-labeled myocardial blood flow agents, there is a need for a simple technique for quantitation of infarcted or jeopardized myocardium (IM). This study provides an in vitro validation of a simple technique based upon the analysis of three short-axis slices through the heart following emission computed tomography. All acquisitions were performed using a static cardiac phantom containing pertechnetate Tc 99 m. Activity in the phantom was adjusted so that the count density and myocardial-to-background ratio were comparable to those observed in patients. Plastic insets (range of sizes = 4%-72% of myocardium) were used to simulate transmural infarctions. Eighteen studies were acquired, each over 180° into a 64 × 64 matrix. Data were reconstructed using a Ramp Hanning filter with cut off at 0.7 times the Nyquist frequency. Short-axis slices of the myocardium were then generated, and representative apical (A), mid-ventricular (MV), and basal (B) slices were selected. For each slice, a circumferential profile was generated, and the average radius (R) was measured. The fraction (F) of the profile falling below a threshold value was considered to represent IM. Total IM was given by %IM =100 x (R B F B +R MV F MV + 0.67R A F A)/(R B +R MV + 0.67R A), where the subscripts to R and F refer to the relevant short-axis slices. For a threshold set at 60% of peak, measured IM agreed closely with true IM (R 2=0.98, measured IM =1.01 x true IM −1.35). Measurement of % IM was not distorted by variations in slice radius or in slice selection. Maximum error in % IM occurred with a change in location of the infarct (approximately 4% for opposing walls). This technique permits rapid and accurate assessment of % IM with99mTc-labeled myocardial blood flow agents. Springer-Verlag, 1990 SPET nationallicence Infarct size nationallicence Cardiac phantom nationallicence O'Connor Michael Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut Hammell Thomas Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut Gibbons Raymond Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut European Journal of Nuclear Medicine Springer-Verlag 17/1-2(1990-01-01), 69-76 0340-6997 17:1-2<69 1990 17 259 https://doi.org/10.1007/BF00819407 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00819407 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- O'Connor Michael Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut NATIONALLICENCE 700 1- Hammell Thomas Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut NATIONALLICENCE 700 1- Gibbons Raymond Department of Diagnostic Radiology and Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 55905, Rochester, MN, USA aut NATIONALLICENCE 773 0- European Journal of Nuclear Medicine Springer-Verlag 17/1-2(1990-01-01), 69-76 0340-6997 17:1-2<69 1990 17 259 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer