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H Koito

Publications and source records attributed to H Koito.

At least 37 records · Page 2Linked to original sources
PubMed1993

[Gadolinium-DTPA magnetic resonance imaging in the diagnosis of left atrial myxoma in the elderly].

A 85-year-old woman consulted our hospital with general fatigue, palpitation and chest discomfort changing with different postures. Her electrocardiogram showed sinus tachycardia, atrial premature beats and left atrial overload. 53% cardiothoracic ratio, slightly protruding third arch of the cardiac silhouette and dilated pulmonary artery were seen on the chest X-ray. Two dimensional echocardiography revealed a mass in the left atrium although the quality of echocardiography was suboptimal due to her thoracic deformity. There was no uptake of T1-201 or Ga-67 by the mass. The four-chamber view of Tc-99m ECG-gated SPECT radionuclide angiocardiography showed a filling defect in the left atrium. The T1 weighted magnetic resonance imaging revealed a left atrial mass with relatively low signal intensity. After intravenous injection of Gadolinium-DTPA the signal intensity of the mass increased significantly and the contrast of the mass was improved. The size of the mass was 4 x 4 x 3 cm with a stalk connecting to the interatrial septum. These findings were compatible with left atrial myxoma. Gadolinium-DTPA magnetic resonance imaging is useful in diagnosing left atrial myxoma because it provides information on the size, anatomical location, relationship with other cardiovascular structures and even the characteristics of the mass.

Aged↗
PubMed1992

Enhanced monoamine release in the median preoptic area following reduced extracellular fluid volume in rats.

The role of monoaminergic neural inputs to fluid regulatory systems in the median preoptic nucleus (MnPO) was investigated by examination of monoamine metabolism during reduction of systemic extracellular fluid volume in freely moving rats. Extracellular fluid volume was decreased iso-osmotically by subcutaneous polyethylene glycol (PEG), and extracellular noradrenaline (NA), dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) were measured using intracerebral microdialysis techniques. PEG treatments significantly increased NA, DA and DOPAC release in the MnPO area. The results suggest that monoaminergic neural systems in the region of the MnPO are important in the control of extracellular fluid balance.

Animals↗
PubMed1992

[Radiation therapy for patients with obstructive jaundice caused by carcinoma of the extrahepatic biliary system].

From February 1980 through September 1990, 92 patients with obstructive jaundice resulting from biliary tract cancer registered at Shikoku Cancer Center Hospital or Ehime University Hospital. Radiation therapy (RT) was used to treat 38 of these patients (30 with carcinoma of the extrahepatic bile duct, excluding ampulla of Vater, and eight patients with carcinoma of the gallbladder). Of 38 patients, 11 underwent intraoperative radiation therapy (IORT), and 27 were treated by external radiation therapy (ERT) alone. In contrast, 54 patients (39 with carcinoma of the extrahepatic bile duct and eight with carcinoma of the gallbladder) were not treated by RT. All jaundiced patients received external and/or internal biliary drainage of some kind. Among patients undergoing biliary drainage with a catheter, 21 patients who underwent RT (four with IORT) survived significantly longer than 19 patients who did not (generalized Wilcoxon test: p less than 0.05). There were no significant differences in survival between 7 patients with recanalization and 11 patients with no recanalization. Concerning the survival of laparotomized patients, excluding those with complete resection or perioperative death, eight patients treated with postoperative ERT survived longer than 12 patients who did not have postoperative ERT (not significantly). Eleven patients underwent IORT. A patient with unresectable carcinoma of the hilar bile duct survived 2 years and 3 months after a combination treatment of ERT and IOTR. In four of eight autopsied patients, radiation effects of Grade II were observed (Oboshi and Shimosato's evaluation system for the histological effects of radiation therapy). Our experience suggests that RT is effective in patients with obstructive jaundice caused by carcinoma of the biliary system.

Adenocarcinoma↗
PubMed1990

Comparison with radionuclide angiography of two new geometric and four nongeometric models for echocardiographic estimation of left ventricular ejection fraction using segmental wall motion scoring.

Two new echocardiographic methods for estimating left ventricular ejection fraction, both based on segmental wall motion scoring on a continuous scale, were developed and compared to radionuclide angiography in 50 patients. The first method used a geometric model in which the ventricle was represented by a tubular base section joined to a hemielliptical apex section, each containing 4 quadrants. Contraction was scored visually in 12 regions of the ventricle. The 12 scores were converted to dimensional shortenings, which were then used to calculate separate ejection fractions for each of the 8 quadrants. These 8 values were averaged to obtain the global ejection fraction. Assuming an elliptical end-systolic cross-section shape for each quadrant, the correlation between the echocardiographic and radionuclide ejection fractions was 0.917 with a regression slope of 0.93 and an intercept of 1.5. Results were identical assuming circular end-systolic quadrant shapes. The second approach used a linear combination of the mean wall motion score at the base, midleft ventricle and apex to predict ejection fraction. Coefficients for the 3 mean scores were optimized by least squares best fit with radionuclide ejection fraction in all 50 patients. The simplest linear model showed a correlation of 0.90 between the echocardiographic and radionuclide ejection fraction but underestimated low, and overestimated high, ejection fractions. However, these systematic errors could be removed by regression, which added a constant term of 8.1 and a slope factor of 0.87 to the linear model, improving the correlation with radionuclide ejection fraction to 0.91.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Two cases of hepatocellular carcinoma with omental mass].

Hepatocellular carcinoma rarely causes disseminated metastasis or distant metastasis. We have recently encountered two cases of hepatocellular carcinoma with omental mass. In the first case, we misdiagnosed the omental metastasis as part of the primary tumor. In the second case, omental mass was hypervascular on angiography and this was very useful for an exact diagnosis.

Aged↗
PubMed1989

[Diagnostic value of the reflux sign in cholescintigraphy after administration of a gallbladder contracting agent--a comparison with X-ray cholangiography].

This study reviewed 25 patients with the reflux sign in cholescintigraphy to assess its diagnostic value in evaluating biliary passage. After at least 4-hour fasting 5 mCi of 99mTcPMT or p-butyl IDA was injected intravenously and serial images were recorded before and after intramuscular injection of 10 micrograms of ceruletide diethylamine (caerulein). The reflux sign was determined positive when increased radioactivities in the left hepatic duct (minor reflux; MIR) or more peripheral intrahepatic ducts (major reflux; MAR) were recognized after injection of caerulein. The reflux sign was found in 28 of 237 (12%) studies. Direct and/or indirect X-ray cholangiograms were available in 25 (MIR; 15, MAR; 10). They included common bile duct (CBD) stone in 4, dilated CBD in 4, biliary dyskinesia (BD) in 4, chronic pancreatitis (CP) in 4, gallbladder (GB) stone in 3, duodenal ulcer (DU) in 2, CBD adenoma, pancreatic pseudocyst (PP), duodenal diverticle (DD), and acute cholangitis (AC) in 1 each. Their serum bilirubin levels were within normal limit in all but 2 at the time of cholescintigraphy. Transit time of radionuclides to the duodenum was found prolonged more than 60 min in 17 (68%) patients and persistent pooling in the CBD was found in 8 (28%) patients on scintigrams. The diameter of the CBD on X-ray cholangiogram was ranged 4 to 17 mm. Dilated CBD of more than 10 mm was found in 13 (52%) patients and apparent stenosis of the CBD in 6 (24%) patients. MAR seemed to correspond to increased diameter of the common hepatic more than 2 mm after caerulein injection in DIC. No abnormal findings in X-ray cholangiography was found in 10 (40%) patients including 3 with BD, 2 with GB stone, 2 with DU, 1 each with CP, PP, and AC. All those patients demonstrated MIR. We concluded that major reflux (MAR) sign was helpful in detecting an incomplete obstruction of the CBD, especially in patients with slightly to mildly dilated CBD.

Adult↗
PubMed1987

Supraventricular arrhythmias in the late hospital phase of acute Q-wave myocardial infarction. Supraventricular arrhythmia in myocardial infarction.

To assess the correlates of supraventricular arrhythmia (SA) in the late hospital phase of acute Q-wave myocardial infarction (MI), continuous 24-h ambulatory electrocardiographic monitoring, gated cardiac pool scan, modified exercise test, and chest x-ray were reviewed in 102 patients. Supraventricular tachyarrhythmias were seen in 11 patients, atrial premature beats in 42 patients; 49 patients did not have SA. Multiple discriminant analysis was used to determine the important variables contributing to the occurrence of SA. Variable included age, sex, history of previous MI, hypertension, location of MI, moist rales at time of admission, cardiothoracic ratio, ejection fraction, wall motion abnormality, exercise test result, duration of exercise and use of digitalis. Moist rales, digitalis, age and cardiothoracic ratio were the predictors of SA. Aging, hemodynamic change imposed on the left ventricle, and arrhythmic effects of digitalis are the major factors associated with SA in the late hospital phase of acute MI.

Atrial Fibrillation↗
PubMed1987

[Right ventricular function in patients with chronic right ventricular infarction].

To assess right ventricular function in patients with chronic right ventricular infarction, Tc-99m angiocardiography was performed in 64 patients one to three months after the onset of myocardial infarction. These patients were categorized into four groups according to their hemodynamic data in the acute stage using the Forrester classification: 39 patients in group I, 15 in group II, eight in group III and two in group IV. Mean right atrial pressure was nearly equal to or greater than diastolic pulmonary arterial pressure in all patients in group III. We calculated right ventricular ejection fraction (RVEF) and the right ventricular end-diastolic volume index (RVEDVI) as the parameter of right ventricular function, and assessed right ventricular wall motion using the right ventricular regional ejection fraction images (RVREFI). 1. RVEF in group III (25 +/- 3%) was significantly lower than those in groups I, II and IV (44 +/- 6%, 45 +/- 7% and 37 +/- 4%, respectively), and RVEF of all patients in group III was less than 30%. 2. RVEDVI in group III (150 +/- 25 ml/m2) was significantly greater than those in groups I, II and IV (74 +/- 20 ml/m2, 59 +/- 14 ml/m2 and 91 +/- 36 ml/m2, respectively). 3. RVREFI in group III decreased at the inferior and/or septal regions of the right ventricle, indicating wall motion abnormalities at the corresponding sites. 4. Six patients in group III were examined by coronary angiography and all had definite lesions in the proximal portion of the right coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗