Do reconstruction filters really effect the volume and ejection fraction calculation with 99^mTc-sestamibigated myocardial SPECT?

ECG -gated myocardial perfusion imaging is a sensitive test for diagnosis of ischemia as well as scarred myocardium. It provides additional information on global and regional myocardial contractile function. A number of methods are available to calculate left ventricular volumes and ejection fractions, which depends on various technical and patients specific factor. This study was carried out to measure effect of reconstruction filter in calculations of left ventricularend diastolic volume (EDV) and end systolic volume (ESV) and left ventricular ejection fraction (LVEF) from 99mTc-sestamibi myocardial perfusion imaging. 99mTc-sestamibi-gated SPECT myocardial perfusion imaging was performed in 90 patients. Studies were reconstructed with Butterworth and Metz filters. Mean ejection fraction with Butterworth and Metz filter are 64.3 and 64.2, respectively. Mean EDV is for Butterworth and Metz filters are 77.3 and 78.5 ml, respectively. While ESV was 36.49 and 36.63 ml, stroke volume calculated was 41.54 and 42 ml for Butterworth and Metz filters, respectively. Pearsons's correlation coefficients between results calculated with Metz and Butterworth filters were 0.994 for ESV, 0.996 for EDV, 0.966 for LVEF and 0.925 for SV. Student 't' test was applied on the data and no significant difference was noted between parameter estimated by Butterworth or Metz filter. This study shows that difference of filter application has no significant effect in computing left ventricular function parameters