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Biomedical subjects

T Kozuka

Publications and source records attributed to T Kozuka.

At least 181 records · Page 10Linked to original sources
PubMed1990

[Myocardial adrenergic derangement due to myocardial ischemia: decreased myocardial uptake of I-123 metaiodobenzylguanidine after PTCA in a patient with effort angina].

Regional denervation of adrenergic nerves has been clinically demonstrated in patients with myocardial infarction using I-123 metaiodobenzylguanidine (MIBG) scintigraphy. However, it is not clarified whether adrenergic denervation can be induced by prolonged myocardial ischemia as well as by myocardial infarction. This case with effort angina had 99% stenosis of right coronary artery and showed perfusion defects at inferior myocardial regions in the exercise thallium-201 study. However, inferior wall motion estimated by echocardiography and left ventriculography was normal indicating the absence of myocardial infarction. After percutaneous transluminal coronary angioplasty for the stenosis, I-123 metaiodobenzylguanidine (MIBG) and thallium-201 (Tl-201) myocardial scintigraphies were done to estimate the therapeutic effect of PTCA. Although the Tl-201 study during exercise showed normal findings indicating the success of PTCA, marked defects was detected at inferior myocardial regions in the I-123 MIBG studies just after and 4 hours after an intravenous injection of I-123 MIBG. These results suggest that adrenergic derangement may be induced by prolonged myocardial ischemia and may persist for periods even though myocardial perfusion is normalized.

3-Iodobenzylguanidine↗
PubMed1990

[Imaging diagnosis of protein-losing enteropathy by 99mTc-labeled serum albumin].

Abdominal scintigraphy with intravenous injection of 99mTc-labeled serum albumin was performed in 6 patients with protein-losing enteropathy (PLE) and 3 patients with non-gastrointestinal tract disorders. In 3 out of 6 patients with PLE, abnormal radioactivity was observed in the ileum region 3 hours after injection, and thereafter clear colon image was obtained. In the remaining 3 patients, the colon was visualized 24 hours after injection. On the other hand, in all patients with non-gastrointestinal tract disorders, no abnormal radioactivity was observed in the abdomen until 24 hours after injection. These results indicate that gastrointestinal protein loss could be demonstrated by scintigraphy with intravenously administered 99mTc-labeled serum albumin. In one healthy subject, 99mTc-labeled serum albumin was administered orally and abdominal scintigraphy was performed. Gastrointestinal tract image was only observed and no other image was demonstrated until 24 hours after oral administration. This result suggests that 99mTc excreted into the gastrointestinal tract is not reabsorbed. Therefore, abdominal scintigraphy with 99mTc-labeled serum albumin appears to be a simple and useful method for diagnosis of PLE.

Adult↗
PubMed1990

A new apparatus for brain imaging: four-head rotating gamma camera single-photon emission computed tomograph.

The development of a new rotating gamma camera SPECT device for imaging the brain was undertaken with the objective of achieving the highest full volume imaging spatial and temporal resolution performance. For this purpose, four rectangular gamma camera detectors were arranged as close to the head as possible, and united in a block to insure detector head registration and alignment as well as to enable rotation stability at high speeds. Phantom and clinical studies performed demonstrated 42 sequential, 4-mm thick transaxial images acquired in one scan and with sufficient volume to permit the entire cerebrum and cerebellum to be imaged with high sensitivity. The central field of view reconstructed spatial resolution measured 7.0 mm full width of half maximum utilizing the high-resolution collimator, and tomographic images of arbitrary planes including sagittal and coronal demonstrated equally high resolution. The high sensitivity and high speed rotational acquisition capability of the device permits dynamic SPECT studies to be carried out in the analysis of rapidly varying radiotracer concentrations.

Brain↗
PubMed1990

External carotid artery embolization of dural arteriovenous malformations involving the cavernous sinus. Outcome and role of venous thrombosis.

Nine patients with dural arteriovenous malformations (AVMs) in the region of the cavernous sinus were treated by means of external carotid artery (ECA) embolization using polyvinyl alcohol. All AVMs received vascular supply from both the ECA and the internal carotid artery. Seven cases were clinically cured after embolization, while 2 cases with cortical venous drainage and high flow through the shunt were not completely cured. Venous thrombosis was observed in 5 cases before and in 9 after embolization. In 6 cases the drainage pattern changed owing to venous thrombosis. Complete thrombosis of the cavernous sinus was found on a follow-up angiography in 2 cases. Formation of venous thrombosis and occlusion of feeding arteries are crucial factors for success of ECA embolization. Dural AVMs with cortical venous drainage and high flow cannot be relieved by ECA embolization alone owing to difficulty in obtaining thrombosis of the veins.

Adult↗
PubMed1990

[Estimation of portosystemic shunt by transrectally administered 123I-IMP].

Portosystemic shunt index was estimated in 7 patients without liver disease and 95 patients with various liver diseases by portal scintigraphy with transrectally administered 123I-iodoamphetamine (IMP). The shunt index was 0% in patients without liver diseases, 5.3% in acute hepatitis, 5.9% in chronic inactive hepatitis, 11.4% in chronic active hepatitis, 56.6% in compensated liver cirrhosis and 88.1% in decompensated liver cirrhosis. The shunt index was significantly higher in liver cirrhosis, especially decompensated stage. In 5 of 9 patients with acute hepatitis, shunt index was 0%. In 3 of remaining 4 patients with elevated shunt index, shunt index became 0% within 1-2 months. Significant relationship was observed between the shunt index and hepatic function tests such as ChE, albumin, gamma-globulin and ICG-R15. These results suggest that the shunt index is independent of hepatic cell necrosis and reveals the shunted blood flow exactly. Therefore, this technique is useful for evaluating the portosystemic shunt in various liver diseases.

Administration, Rectal↗
PubMed1990

[Gallium-67 myocardial imaging for the detection of adriamycin cardiomyopathy].

To detect Adriamycin cardiomyopathy, radionuclide myocardial imagings with Tl-201, Tc-99m pyrophosphate, I-123 metaiodobenzylguanidine and Ga-67 were performed in a 49 year-old-woman receiving Adriamycin (a total dose of 230 mg/m2) for the treatment of breast cancer. This patient demonstrated symptoms of congestive heart failure 2 months after the last intravenous administration. At the period of performing the radionuclide studies, echocardiographic LV ejection fraction (EF) was 22%. Despite severe deterioration of cardiac function, Tl-201 SPECT demonstrated no defect and Tc-99m pyrophosphate (PYP) SPECT demonstrated no positive finding. I-123 metaiodobenzylguanidine (MIBG) scintigraphy demonstrated no regional defect. However, I-123 MIBG washout rate during 4 hours was markedly enhanced, probably reflecting abnormalities of norepinephrine kinetics due to the progression of heart failure. Compared to these pharmaceuticals, Ga-67 was diffusely accumulated in the heart. Then, 5 months after the first study, when LV EF improved to 30% and congestive symptoms disappeared probably owing to beta-blockade therapy, myocardial accumulation of Ga-67 markedly reduced. It has been reported that Ga-67 accumulates in malignant tumor cells and leukocytes. Since, in Adriamycin cardiomyopathy, myocardial accumulation of leukocytes with myocardial fibrotic changes have been histologically demonstrated, the results of Ga-67 scintigraphy may reflect the accumulation of leukocytes. Thus, this case indicates that Ga-67 scintigraphy is advantageous for detecting Adriamycin cardiomyopathy and may be more useful than Tl-201 and Tc-99m PYP scintigraphies.

Doxorubicin↗
PubMed1989

[Contrast material for CT of the liver and spleen--an experimental study on the safety of lipiodol-iopamidol emulsion].

Iodinated oil (Lipiodol Ultra-Fluid) emulsified by non-ionic contrast material (Iopamidol) featuring much iodine and surface activity, was developed for computed tomography (CT) of the liver and spleen. The stability study revealed that Lipiodol-Iopamidol Emulsion (LIE, 1-6 microns in diameter) stored 2 weeks under refrigeration showed no visible change in globule size distribution. The biodistribution study in six rabbits revealed that LIE injected into the vein was accumulated in the liver, spleen, and lung, which have reticuloendothelial cells, however not accumulated in the brain, kidney, and serum, which have no reticuloendothelial cells. The disruption to the blood brain barrier (BBB) was assessed using Evans' Blue dye as a visual marker. After the coarse emulsion (larger than 8 microns in diameter) was injected into the internal carotid artery of three rats, the permeability of BBB increased. However, after the injection of LIE, no increased permeability of BBB was noted. Our results suggest that LIE will have a clinical application in the detection of focal hepatic and splenic lesions.

Animals↗
PubMed1989

[Siderotic regenerating nodules in liver cirrhosis--evaluation by gradient echo (FLASH) imaging 1.5T].

In three patients with histologically proven liver cirrhosis, a large number of small, low-intensity nodule(SLIN)s was clearly seen on gradient echo(GRE) images which are sensitive to field inhomogeneity. A histological study revealed that the SLINs corresponded to the regenerating nodules, laden with iron, of liver cirrhosis. As TE was prolonged, the SLINs increased in size in all three cases and fused with each other in one of three cases on GRE images. This phenomenon suggests that the magnetic susceptibility effect due to iron included in the regenerating nodules is the cause for the regenerating nodules shown as SLINs on GRE images, and that one SLIN does not always correspond to one regenerating nodule. We conclude that GRE images should be considered important for diagnosis of regenerating nodules in liver cirrhosis.

Female↗
PubMed1989

[Magnetic resonance imaging of the lumbar spine--comparison of multiple spin echo and low flip angle gradient echo imaging].

Sixteen patients including 13 cases with disk herniation and 3 cases with spondylosis of lumbar spine were examined on a resistive MRI system operating at 0.1 T. All lesions were studied with both multiple spin echo (MSE) and low flip angle gradient echo (LF) techniques to evaluate which technique is more effective in detecting the disk degeneration and the indentation on subarachnoid space. MSE images were obtained with repetition time (TR) of 1100-1500 ms or cardiac gating, an echo time (TE) of 30, 60, 90, 120, 150, and 180 ms symmetrical 6 echoes, and total acquisition time of more than 281 sec. LF images were obtained with TR of 500, 250, and 100 ms, TE of 18 ms, a flip angle of 30 degree, and total acquisition time of 128 sec. Eleven lesions of spinal disk degeneration and 12 of indentation on subarachnoid space were detected with LF. On the other hand, 26 lesions of spinal disk degeneration and 38 of indentation on subarachnoid space were detected with MSE. Although the parameters of LF employed in this study were relatively effective to emphasize T2*-based contrast, the ability of LF in detection of spinal disk degeneration and indentation on subarachnoid space is less than that of MSE. Signal contrast to noise ratios for normal disk and degenerative disk, epidural-fat and disk herniated material, CSF and disk herniated material, and epidural-fat and CSF were less than 4 with LF, but more than 4 with MSE.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1989

[The results of radiation therapy of patients with pure seminoma of the testis].

Between 1967 and 1985, 75 patients with pure seminoma of the testis were treated with radiation therapy for periaortic and ipsilateral iliac areas following orchiectomy at the Department of Radiology, Osaka University Hospital. All patients except three were followed at least 2 years. Concerning patients who received 28-30 Gy, all of 48 patients with N0 disease were controlled and alive 2 to 20 years after radiation therapy. All of four patients with N1 disease were controlled and alive 6 to 16 years after radiation therapy. Six of 7 patients with N2 disease were controlled and alive 6 to 19 years after radiation therapy but one patient with T1N2 disease who received 30 Gy to periaortic and ipsilateral iliac areas had recurrence in a paraaortic lymph node 11 months after radiation therapy. As for patients with N3 disease two patients were controlled after 38 Gy and 48 Gy, respectively. No complication was observed after radiation therapy. No sterility seemed to be induced by irradiation to periaortic and ipsilateral iliac areas. It may be concluded that dose of 30 Gy to periaortic and ipsilateral iliac areas is recommended for patients with N0 disease. However, for patients with N1 or N2 disease higher dose of 35 Gy or more is recommended.

Adult↗
PubMed1989

Allergic contact sensitivity to quinophthalone.

A 73-year-old patient, diagnosed as having seborrheic dermatitis, was patch tested with his hair preparations. The hair stick gave a positive reaction. Among its ingredients, D & C Yellow No. 11, from 0.0001% to 0.1%, and perfume showed positive reactions. D & C Yellow No. 11 was found to consist only of quinophthalone by chemical analyses. The concentration of quinophthalone in the hair stick was determined as 9.41 ppm w/w by high-performance liquid chromatography.

Aged↗
PubMed1989

Cross sectional echocardiographic anatomy of common atrioventricular valve in atrial isomerism.

The morphology of the common atrioventricular valve and its relation to the ventricles was assessed by cross sectional echocardiography in 17 patients with atrial isomerism--four with left isomerism and 13 with right isomerism. In 13 patients the atrioventricular valve consisted of four leaflets: a large anterosuperior leaflet, two lateral leaflets, and a posteroinferior leaflet. The remaining four patients had two anterosuperior leaflets. Five patients had hearts with a double inlet right ventricle and all of them had a rudimentary left ventricle. All the commissures were attached to the right ventricle. Five patients showed severe right ventricular dominance. The atrioventricular morphology in these five hearts differed from that in the patients with the usual atrial arrangement, concordant atrioventricular connection, and hypoplasia of the left ventricle. Only the anterosuperior leaflet bridged the rudimentary left ventricle, and the posteroinferior leaflet was tethered to the ventricular septal crest. Six patients had a biventricular atrioventricular connection and two of them showed mild right ventricular dominance. The atrioventricular morphology in these hearts was the same as that seen in the patients with usual atrial arrangement and a concordant atrioventricular connection. The remaining patient showed dominance of the left ventricle. Only the anterosuperior leaflet bridged the rudimentary right ventricle in this heart.

Adolescent↗
PubMed1989

Hepatic venous outflow obstruction: evaluation with pulsed duplex sonography.

Pulsed Doppler sonography was performed in six patients with hepatic outflow obstruction (five with Budd-Chiari syndrome and one with hepatic venocclusive disease) to assess its usefulness in evaluating the altered hemodynamics in this disease. Doppler signals were obtained from the inferior vena cava (IVC) and from hepatic, collateral, and portal veins. Normally, the IVC and hepatic veins show phasic forward (toward the heart) flow. In Budd-Chiari syndrome, the blood flow in the IVC and hepatic veins was absent, reversed, turbulent, or continuous. These Doppler findings were thought to be characteristic of Budd-Chiari syndrome. The portal velocity was reduced (n = 4) or increased (n = 1). The former was considered typical of Budd-Chiari syndrome. In hepatic venocclusive disease the IVC and major hepatic veins showed normal phasic flow; flow velocity in the portal vein was increased. Doppler sonography was found to correlate well with therapeutic results and angiographic findings.

Adult↗
PubMed1989

Radiographic type p pneumoconiosis: high-resolution CT.

High-resolution computed tomography (CT) was performed in 90 patients with pneumoconiosis who had small rounded opacities on radiographs. The CT appearances of radiographic type p small rounded opacities in 55 patients were compared with the appearances of type q and r opacities. Radiographic type p pneumoconiosis on high-resolution CT scans was characterized by tiny binary branching structures or a gathering of a few dots. In 21 of the 55 patients, nonperipheral, small areas of low attenuation with a central dot were found. On the basis of CT-pathologic correlation in two postmortem specimens, these tiny opacities and areas of low attenuation corresponded to irregular fibrosis around and along the respiratory bronchioles and to focal-dust emphysema, respectively. Focal emphysema was most commonly found in pneumoconiosis with p-type changes and can be identified with high-resolution CT scanning. The addition of high-resolution CT to chest radiography is useful in achieving more accurate categorization of the lesions.

Humans↗
PubMed1989

Primary thyroid lymphoma: comparison of CT and US assessment.

Sixteen patients with primary thyroid lymphoma were studied with computed tomography (CT) and ultrasonography (US), and findings were compared. In 13 of 16 patients, detection of the primary tumor with US and CT were comparable. US was superior in one case, and CT in another. One tumor was not detected with either technique. Thyroid lymphomas appeared as extremely hypoechoic masses intermingled with echogenic structures. Although echogenicity of unaffected thyroid tissue was also low because of coexisting Hashimoto thyroiditis, thyroid lymphomas were relatively well differentiated as markedly hypoechoic areas. Five tumors showed contiguous spread into both thyroid lobes. US and CT were equally sensitive in detection of superficial lymphomatous nodes (seven of 16 cases). CT was superior to US in the definition of tumor extent in two patients with intrathoracic tumor extension and in one with laryngeal invasion. In patients with suspected thyroid lymphoma, CT should be the primary radiologic technique used for diagnosis and staging; US will be useful in local follow-up.

Aged↗
PubMed1989

Slippery coaxial catheter system.

A slippery coaxial, 3-F catheter device was developed for selective angiography, embolization, and infusion of chemotherapeutic agents. The device comprises three parts: an 0.018-inch, plastic-coated guide wire; a 3-F coaxial catheter; and a 6.5-F guiding catheter. Both the guide wire and coaxial catheter are coated with hydrophilic polymer, which becomes slippery when immersed in water. Experience with four patients indicates the new coaxial catheter device is capable of traversing tortuous vessels smoothly and safely, and it permits infusion of chemotherapeutic agents and 1-mm gelatin particles.

Adult↗
PubMed1989

Long-term coenzyme Q10 therapy for a mitochondrial encephalomyopathy with cytochrome c oxidase deficiency: a 31P NMR study.

For 2 years we administered high doses of coenzyme Q10 (CoQ) to a patient having mitochondrial encephalomyopathy with cytochrome c oxidase deficiency. Abnormal elevation of the serum lactate per pyruvate ratio and the increased concentration of serum lactate plus pyruvate induced by exercise decreased with CoQ treatment. This therapeutic effect continued for 2 years. 31P nuclear magnetic resonance spectroscopy showed acceleration of the postexercise recovery of the ratio of phosphocreatine to inorganic phosphate in muscle during CoQ treatment. These observations support the beneficial effect of CoQ on the impaired mitochondrial oxidative metabolism in muscle. Also, impaired central and peripheral nerve conductivities consistently improved during CoQ treatment. These results indicate that CoQ has clinical value in the long-term management of patients with mitochondrial encephalomyopathies, even though there are clinical limitations to the effects of this therapy.

Adult↗