[en] The method of automating the judgement works using photographs in radiation nondestructive inspection with a simple type image processor on the market was examined. The software for defect extraction and making binary and the software for automatic judgement were made for trial, and by using the various photographs on which the judgement was already done as the object, the accuracy and the problematic points were tested. According to the state of the objects to be photographed and the condition of inspection, the accuracy of judgement from 100% to 45% was obtained. The criteria for judgement were in conformity with the collection of reference photographs made by Japan Cast Steel Association. In the non-destructive inspection by radiography, the number and size of the defect images in photographs are visually judged, the results are collated with the standard, and the quality is decided. Recently, the technology of image processing with personal computers advanced, therefore by utilizing this technology, the automation of the judgement of photographs was attempted to improve the accuracy, to increase the inspection efficiency and to realize labor saving. (K.I.)

[en] An automatic classification in image processing has been developed by use of a personal computer according to JIS codes radiographs for nondestructive testing. The precision of image processing by an automatic classification method was 100 % for the high contrast radiographs, and 45 % for the low contrast radiographs. (author)

[en] The contrast and the quality of images given by image processing on minimal defects of thickness metal have generally been low insufficient. To improve the contrast and the quality, we applied the X-ray TV-system which made it possible to reconstruct images by processing density histgrams using the integral calculus manner of input images. The result showed that the quality of images and perceptibility were improved. (author)

[en] Correlation studies were carried out between thallium-201 myocardial perfusion images and vectorcardiograms in 77 patients with myocardial infarction (48 anterior and 29 inferior infarctions) and 30 patients with hypertrophic cardiomyopathy. A quantitative method was developed; myocardial ²⁰¹Tl uptake index (a relative myocardial activity to background, MUI) and myocardial ²⁰¹Tl uptake ratio (a ratio of regional myocardial counts to maximal myocardial counts, MUR) were utilized to differentiate myocardial infarction from hypertrophic cardiomyopathy, and evaluate them. A fairly good agreement between left ventriculograms and myocardial perfusion images was obtained in myocardial infarction (diagnostic accuracy 95.1% in anterior and 75.6% in inferior infarction). In anterior infarction the linear relationship of r = -0.58 (p < 0.001) was obtained between asynergy index and mean anterior MUR. A highly significant correlation was observed between anterior MUR and the instantaneous 24 msec Z component (r = -0.80, p < 0.001). In inferior infarction, Qy/Ry was correlated to inferior MUR (r = -0.58, p < 0.001). In hypertrophic cardiomyopathy, four types of hypertrophic sites were classified with ²⁰¹Tl images (septal, apical and anterior, apical and septal, and anterior dominant types). Azimuth angles of instantaneous 10 msec vector were directed right-anteriorly (mean 114.5 degrees) in septal hypertrophy, and left-anteriorly (mean 84.9 degrees) in apical and anterior hypertrophy. Elevation angle of maximal T vector in apical hypertrophy was deviated superiorly (mean 102.6 degrees). There was a good correlation (r = 0.60, p < 0.001) between the magnitude of spatial maximal QRS vector and lateral wall MUR. (author)

[en] We analyzed right ventricular function using first-pass radionuclide angiocardiography (FP-RNA) in 11 normal subjects, 28 patients with coronary artery disease (CAD) and 11 patients with right ventricular pressure overload. In normal subjects, right ventricular ejection fraction (RVEF) averaged 50.8 +- 8.7% (m +- SD). RVEF in patients was significantly decreased than that in normal subjects. Several parameters (RVEF, maximal systolic and diastolic dV/dt) obtained by FP-RNA were compared with hemodynamic parameters obtained by cardiac catheterization. RVEF and maximal systolic dV/dt correlated with the mean pulmonary artery pressure and pulmonary vascular resistance (r=-0.46, r=-0.56). While RVEF was less dependent on preload, highly dependent on afterload. In conclusion, we considered that the FP-RNA was a useful method to evaluate right ventricular function in CAD and other heart disease. (author)

No abstract available

[en] To determine whether the departure parameters derived from a ''departure loop'' of a vectorcardiogram are more accurate than conventional spatial parameters in evaluating myocardial infarct size, 74 patients with first-onset myocardial infarction (MI) were studied. The correlation between the departure parameters (amplitudes in scalar leads of the departure loop) and the percent defect volume of thallium myocardial scintigrams (%DV) was compared with that of the spatial parameters (magnitude, azimuth, and elevation of the original QRS loop). In anteroseptal MI, the amplitude of a 20-msec vector in the z-axis and the azimuth of a 30-msec vector (H₃₀) were significantly correlated with %DV (r=0.783, p<0.001 and r=0.572, p<0.05). In anteroseptal MI with involvement of the lateral wall, the amplitude of a 30-msec vector in the x-axis and H₃₀ showed significant correlation with %DV (r=0.802, p<0.001 and r=0.772, p<0.01). In inferior and inferoposterior MI, the amplitude of a 30-msec vector in the y-axis and the elevation of a 30-msec vector were significantly correlated with %DV (r=0.920, 0.891, p<0.001 and r=0.871, 0.678, p<0.01, respectively). In conclusion, the departure parameters are more accurate than the spatial parameters for evaluation of myocardial infarct size. (author)

[en] To evaluate whole body distribution and kinetics of Thallium-201 at exercise and redistribution, whole body scintigraphy (WB-S) was performed on 12 normal subjects (N), 19 patients with angina pectoris (AP) and 18 patients with old myocardial infarction (MI). WB-S was obtained using a gamma camera OMEGA 500 and analized by ADAC System IV. We estimated the following parameters from WB-S; 1) %Distribution (%D): the ratio of whole body counts to organ counts 2) washout rate (WR) in each organ. %D of the heart in N, AP and MI was similar at rest and exercise. At exercise, %D of the lung and the liver decreased and %D of thighs increased remarkably than at rest. At supine exercise, the lung indicated high %D and thinghs indicated low %D compared with at upright exercise. WR of the heart in AP and MI was significantly lower than in N (p<0.005, p<0.01) and further decreased proportionally to the number of stenotic coronary arteries and related to the ischemic ST depression of exercise ECG. WR of the heart was not correlation with pressure rate product and this finding suggested that WR of the heart was not prescribed by the tolerance of exercise but related to coronary flow at exercise a certain degree. WR of the lung in MI was significantly higher (p<0.025) and WR of thighs in AP and MI was significantly lower (p<0.025, p<0.05) compared with N. (author)

[en] Segmental analysis of stress and delayed myocardial perfusion imaging (MPI) was performed in 33 patients with coronary artery disease (CAD). They were divided into two groups: 22 patients without previous infarction (Group 1) and 11 patients with prior myocardial infarction (Group 2). Using computer analysis of MPI, 9 region-of-interests (ROIs) were set on the left ventricular image. We defined 3 indices as follows: initial uptake (%) = a ratio of ROI counts to the highest ROI counts on the exercise image; wash out rate (WR) = a ratio of ( (ROI counts on the exercise image) - (those on the delayed image) ) to those on the exercise image; redistribution index (RDI) = a ratio of the maximal WR to WR. In group 1, the region supplied by the coronary artery with significant stenosis showed a lower initial uptake (p lt 0.005) and a higher ROI (p lt 0.001) than the region supplied by the coronary artery without significant stenosis. If an initial uptake less than 83% and/or a RDI greater than 1.15 are defined as abnormal, the senstivity for detecting CAD, including the detection of a stenosis site, was 76% and the specificity was 84%. In group 2, the sensitivity was 76% and the specificity was 80%. The mean WR could also indicate the severity of CAD. In all patients studied, the average of mean WR was 0.451 in one-vessel disease (n = 18), 0.446 in two-vessel disease (n = 6) and 0.305 in three-vessel disease (n = 8). In conclusion, the quantitative evaluation of stress MPI using initial uptake, RDI and WR appear to be useful for noninvasive and objective diagnosis of CAD, particularly in detecting the severity and location of stenotic coronary arteries. (J.P.N.)

[en] In order to evaluate three-dimensional phase changes in ventricular conduction abnormalities, tomographic phase images were constructed in 7 normal subjects, 12 patients with ventricular pacing, 21 patients with bundle branch block and 12 patients with Wolff-Parkinson-White syndrome. Eight to 12 slices of the short-axis ventricular tomographic phase image (TPI) were derived using a 7-pinhole collimator, and compared with planar phase images (PPIs) in left anterior oblique (LAO) and right anterior oblique (RAO) projections. TPIs were excellent for observing biventricular phase changes in the long-axis direction. In 6 cases of complete right bundle branch block with left axis deviation (beyond -30⁰), the phase delay in the left ventricular anterior wall was recognized in 5 cases by TPI, although it was difficult to be detected by PPIs. The site of the pacing electrode was identified by TPI in 11 out of 12 cases, compared to 8 cases by PPIs in LAO and RAO projections. The site of the accessory pathway in Wolff-Parkinson-White syndrome was detected in the basal slice of TPIs in 10 out of 12 cases, compared to 8 cases by PPI in the LAO projection. Therefore, it is obvious that TPIs offer more valid information than PPIs. In conclusion, TPI is useful for investigation of ventricular conduction abnormalities. (author)