Search PubMed⌕ Search

Biomedical subjects

K Kadota

Publications and source records attributed to K Kadota.

At least 199 records · Page 11Linked to original sources
PubMed1983

[Evaluation of myocardial infarction by thallium emission computed tomography].

Thallium myocardial emission computed tomography (ECT) using a rotating gamma camera was undertaken to assess three-dimensional thallium distribution in the myocardium in cases with myocardial infarction (MI). Ninety-one cases with MI and 29 normal persons were examined by thallium ECT and the conventional planar imaging. Diagnostic performance and quantification of MI, and characterization of non-transmural MI were also investigated. In the detection of a perfusion defect, the ECT imaging showed significantly higher sensitivity (96%) than the planar imaging (77%) (p less than 0.001), especially in those with inferior wall MI (95% vs 73%, p less than 0.02) and nontransmural MI (82% vs 27%) (p less than 0.01). The specificity was the same in both techniques (90%), and therefore, higher overall accuracy was obtained by the ECT imaging (94%) than by the planar imaging (80%) (p less than 0.01). The receiver operating characteristic (ROC) curves were obtained from three independent observers for quantitative evaluation of observer detection performance. The ECT curves in each observer were situated in the upper left corner, indicating excellent diagnostic performance. Infarct size was estimated from the extent of the perfusion defect expressed as a percentage of the planar imaging (% defect) and as a volume of the infarcted myocardium (infarct volume). Those parameters were significantly correlated with peak CPK (r = 0.80 and 0.94, respectively), and inversely correlated with left ventricular ejection fraction (r = -0.78 and -0.85, respectively). Thus, the infarct volume calculated from the ECT is considered to permit estimation of infarct size more accurately than % defect from the planar imaging. To characterize nontransmural MI, 11 cases with nontransmural MI were examined by ECT and the findings were compared with those of transmural MI. A perfusion defect was detected in nine of the 11 patients (82%). As compared to those with transmural MI, infarct volume was smaller and the residual activity in an infarct region was higher in cases with nontransmural MI. Thus, the thallium ECT imaging, providing any-angle multisection of the myocardium, permits qualitative and quantitative evaluation of MI accurately.

Humans↗
PubMed1983

[Improved cineangiographic evaluation of hypertrophic cardiomyopathy by biventriculography with angled projection].

Left ventricular cineangiography with angled projection has been designed to overcome limitations of conventional angiography in the diagnosis of various heart diseases. Thus, to delineate the precise extent and degree of the thickness of the ventricular septum and left ventricular free wall in patients with hypertrophic cardiomyopathy, we performed biventriculography with angled projection (angled BVG) in 14 patients with hypertrophic cardiomyopathy (HCM), three with concentric hypertrophy and one with dilated cardiomyopathy. We also performed conventional biventriculography (nonangled BVG) in 9 of these 18 patients. The length of the interventricular septum (LIVS) and the long axis of the left ventricular cavity (LLV) measured by angled BVG (LIVS = 8.07 +/- 1.41 cm and LLV = 9.10 +/- 1.36 cm, n = 9) were significantly longer than those by nonangled BVG (LIVS = 5.88 +/- 1.17 and LLV = 7.15 +/- 1.24, n = 9) (p less than 0.001). In addition, the mitral valve and ventricular septum were visualized more clearly. Systolic anterior motion of the anterior leaflet of the mitral valve was readily identifiable, which was not detected usually by the nonangled method. In summary, angled BVG afforded increased precision in evaluation of the interventricular septum, left ventricular outflow tract and mitral valve in patients with HCM because these structures are seen in profile, an anatomy of the interventricular septum and an abnormal motion of the mitral valve can be better evaluated. Thus, angled BVG is the diagnostic procedure of choice in patients suggestive of hypertrophic cardiomyopathy.

Adult↗
PubMed1982

Estimation of infarct size by myocardial emission computed tomography with thallium-201 and its relation to creatine kinase-MB release after myocardial infarction in man.

We evaluated emission computed tomography (ECT) for thallium-201 (201TI) myocardial imaging in estimating infarct size (IS). In 18 patients in whom IS was estimated enzymatically at the time of the acute episode, planar 201TI perfusion scintigraphy and ECT with a rotating gamma camera were performed 4 weeks after the first myocardial infarction. From the size of 201TI perfusion defects, the infarct area in planar images and the infarct volume in reconstructed ECT images were measured by computerized planimetry. When scintigraphic IS was compared with the accumulated creatine kinase-MB isoenzyme release (CK-MBr), infarct volume determined from ECT correlated closely with CK-MBr (r = 0.89), whereas infarct area measured from planar images correlated less satisfactorily with the enzymatic IS (for an average infarct area from three views, r = 0.69; for the largest infarct area, r = 0.73). Although conventional scintigraphic evaluation is useful for detecting and localizing infarction, quantification of ischemic injury with this two-dimensional technique has a significant inherent limitation. The ECT approach can provide a more accurate three-dimensional quantitative estimate of infarction, and can corroborate the enzymatic estimate of IS.

Adult↗