We recently reported that motion-frozen (MF) computer technique improved image quality

We recently reported that motion-frozen (MF) computer technique improved image quality of myocardial perfusion SPECT without sacrificing count density by reconstruction of perfusion images with all counts shifted to end diastolic (ED) frame. standard supine (S-TPD) and motion-frozen (MF-TPD) datasets with the use of gender-specific standard and MF normal limits. We compared the sensitivity, specificity and receiver operator characteristic curves (ROC) obtained from S-TPD and MF-TPD. Results The area under the curve for MF-TPD was significantly buy 1374828-69-9 larger than for S-TPD for the detection of CAD (70% stenosis) (0.930.25 vs 0.880.32, p<0.05). In 7/31 patients without CAD, MF analysis corrected false positive non-MF results. While sensitivity was the same [93% vs 95% for S-TPD and MF-TPD respectively (p=NS)], MF-TPD experienced higher specificity (77% vs. 55%) and accuracy (89% vs. 80%) (both p<0.05) than S-TPD. Conclusion Motion-frozen processing of myocardial SPECT imaging enhances accuracy of CAD detection in obese patients. tests were used to compare the differences in the paired continuous paired variables. A p-value less than 0.05 was considered significant. For all those statistical analysis tasks, we used the Analyze-It software Version 1.71 (Analyze-It Software, Ltd., Leeds, UK). The receiver-operating-characteristic (ROC) curve was created to analyze the diagnostic overall performance of standard and MF TPD for detection buy 1374828-69-9 of 70% or 50% stenosis. Hanley and McNeil method (13) was utilized for comparing curves, since all the assessments are performed on the same subjects. The Analyze-it software generated the ROC curves with 40C50 threshold points depending on the data. RESULTS Average computing time for MF image creation was 5.12.2 seconds for the 16-frame study with the software applied in C++ language on Microsoft Windows platform (System: Microsoft Windows XP Professional?, Computer: Intel? Pentium? 4 CPU 2.80GHz, 2 GB of RAM). In seven out of the 90 patients, which included four 8-frame gated MPS and three 16-frame gated MPS, manual adjustment of the LV contours derived from gated MPS data was required for MF analysis, while 12 ungated LV contours, which included eight 8-frame gated MPS, needed manual contour correction for standard summed perfusion analysis. None of the patients in normal database populace required any manual adjustment. Average segmental count distributions derived from gender-specific normal databases are offered in Physique 1. The average count distributions are significantly different between MF and standard summed analysis in 6 of 17 segments in males and 7 of 17 segments in females. MF normal perfusion distribution in the apex shows decrease in both genders, while basal anterior, lateral and substandard wall of MF analysis show significant relative count increase in both genders. Physique 1 Segmental comparison of gender-specific standard (left) and motion-frozen (right) mean normal perfusion distribution for males (upper) and females (bottom). Asterisks beside the value of the average Rabbit Polyclonal to Cyclin H % count denote significant differences between standard … The buy 1374828-69-9 average S- and MF-TPD values in normal and abnormal patients as defined by coronary angiography are shown in Table 4. The TPD values were significantly smaller for MF-TPD as compared to S-TPD in both normal patients and patients with CAD. The ROC curves for detection of CAD by MF-TPD and S-TPD are shown in Physique 2. The respective areas under the ROC curves for S- and MF-TPD for detection of 70% stenosis and 50% stenosis are offered in Table 5. The areas under the ROC curves for detection of 70% stenosis are 0.930.025 vs 0.890.032 buy 1374828-69-9 for MF-TPD and S-TPD respectively (p=0.014), implying improved diagnostic accuracy of motion-frozen method. The area under the ROC curve for detection of 50% stenosis by MF-TPD was also significantly greater than that of S-TPD (0.940.024 vs 0.880.033, p=0.006). The diagnostic overall performance of S-TPD and MF-TPD for detection of 50% and 70% stenosis is usually presented in Table 6 and ?and77. Physique 2 ROC curves for detection of 50% stenosis (A) and 70% stenosis (B) by steps of S-TPD and MF-TPD in obese patients (n=90). TABLE 4 Average stress TPD measurements in the study populace by angiographic result TABLE 5 Areas under the ROC curves for detection buy 1374828-69-9 of 50% and 70%.