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冠動脈バイパス術 (CABG) 施行前後において安静201T1心筋SPECTを撮像し左室造影と比較しhibernating myocardiumについて検討した。対象は冠動脈疾患35例である。201T1 SPECTは九つのセグメントに分け, 4段階にスコアリングした。左室造影は七つのセグメントに分け5段階にスコアリングした。CABG前後の結果次の四つに分類された。group I (n=13) は201T1 SPECTおよび壁運動スコアともに改善 (p

A 45-year-old man with suspected recurrent malignant glioma was evaluated by magnetic resonance imaging (MRI), positron emission tomography (PET) and 131I labeled monoclonal antibody G-22 (G-22) scan. Following Gadolinium-DTPA, a TI-weighted spin echo image (TR 500 msec, TE 20 msec) demonstrated a large mass with an irregular margin in the left temporo-parietal area. An 18F labeled fluorodeoxyglucose PET study demonstrated marked accumulations in the left temporo-parietal area. Serial 131I-G-22 scintigraphy was obtained for a week after the injection. The uptake was most increased on the 2nd day after the injection. 131I G-22 was specific for tumor-associated antigens.

Twenty-one patients with initial stage Legg-Calve-Perthes (LCP) disease were examined by three-phase bone scintigraphy, single photon emission scintigraphy (SPECT), and magnetic resonance (MR) imaging. On dynamic study, increased activity was present in the epiphysis or the growth plate in 39%; the corresponding figure for blood-pool images was 94%. Pinhole images demonstrated the lateral stripe of revascularization in 57% of patients. Decreased signal intensity in the epiphysis on T1-weighted images proved to be the most sensitive indicator of epiphyseal necrosis on MR imaging and was absent in only 10% of the cases. The subchondral fracture occurred in 62% (including the above 10% of cases), identified by T1-weighted image. Cartilaginous hypertrophy, detected by T1-weighted image, had a high incidence (81%). Joint effusion was identified on T2-weighted images in 90% of patients. The cross-sectional views provided by SPECT and MR imaging permits a better appreciation of the extent of epiphyseal necrosis in LCP disease.

The most characteristic pathophysiologic change in Buerger's disease or thromboangiitis obliterans (TAO) is considered the breakdown of microcircula tion in the extremity, but this has not yet been proven. The purpose of this study is to examine the damage of microcirculation in TAO objectively, by means of intra-arterial injection of two kinds of radioisotope. In 7 TAO and 4 infraingui nal arteriosclerosis obliterans (ASO) patients, thallium 201 chloride (201 Tl) and 99mTc macroaggregated human serum albumin ( 99mTc-MAA) were administered through bilateral common femoral artery injections. In the planar image of the foot, rectangular regions of interest (ROIs) were placed on the foot muscles and toes. Normalized counts of 99m Tc-MAA in each ROI were divided by that of 201Tl, and the result was defined as the microcirculation damage index, based on their different kinetics. The damage index of the foot muscle was not differ ent between ASO and TAO, but that of the toe was lower in TAO than ASO patients. Lumbar sympathectomy was performed in 5 TAO patients, but it did not improve the damage index. It is concluded that there is breakdown of the microvascular defense system from the beginning of the disease, and critical ische mia make the regional cell function deteriorate as if a precursor to a trophic lesion. Lumbar sympathectomy did not immediately improve microcirculation.

Iodine-131-labeled G-22 monoclonal antibody F(ab')2 fragment reaching specifically with a glioma-associated surface glycoprotein was administered to 12 glioma patients to investigate its use in radioimaging of intracranial gliomas. No immediate or delayed side effects were attributable to antibody injection. Nine patients received the radiolabeled complex intravenously. The images of low-grade gliomas were generally poor and disappeared within 4 days. High-contrast images were obtained beyond the 7th day in high-grade gliomas except one case in the pineal region. Three patients received intraventricular or intratumoral administration. Clear images of all tumors were demonstrated from the 2nd until later than the 7th day. One patient with cerebrospinal fluid (CSF) dissemination of brainstem glioma demonstrated negative CSF cytology after intraventricular administration.

99mTc-labelled hexamethylpropylene amine oxime (HMPAO) is a lipophilic compound with a neutral charge which reflects tumor blood flow and has been previously investigated to estimate brain blood flow. In this study, we attempted to use 99mTc-HMPAO for the evaluation of 18 patients with histologically proven primary lung carcinoma. The eight surgical specimens revealed that viable carcinoma cells were present when the 99mTc-HMPAO accumulated in the tumor, however, extensive tumor necrosis was observed when defective or ring like uptake was seen in the tumor. Qualitative study revealed that when perfusion defects were observed corresponding to the tumor, the possibility of squamous cell carcinoma or large cell carcinoma was high instead of adenocarcinoma. Quantitative analysis revealed that the uptake ratio was statistically different between adenocarcinoma (1.6 +/- 0.1) and squamous cell carcinoma (1.2 +/- 0.4) (P less than 0.05), between squamous cell carcinoma and large cell carcinoma (0.9 +/- 0.1) (P less than 0.05), and also between adenocarcinoma and large cell carcinoma (P less than 0.01). In conclusion, 99mTc-HMPAO may be useful for the evaluation of patients with primary lung carcinoma.

Cardiac metastasis from myxoid liposarcoma is rare. A case is reported of a patient in whom the metastatic cardiac liposarcoma was confirmed by TI-201 SPECT. A 37-year-old man had surgery on his left hip because of a myxoid liposarcoma of the left thigh. Five years later, myocardial perfusion scintigraphy using a TI-201 SPECT showed a perfusion defect in the inferior and posterior part of the left ventricle. At autopsy, a large tumor involving the greater part of the left ventricle wall was noted. Pathologlc findings confirmed the diagnosis of cardiac metastasis from the myxoid liposarcoma

A 27-year-old man with widespread lymphadenopathy had multiple sites of accumulation on Ga-67 imaging. The diagnosis of sarcoidosis was confirmed by biopsy. In addition to Ga-67 uptake in intrathoracic lymphadenopathy, Ga-67 was seen at multiple extrapulmonary sites of sarcoidosis.

Myocardial SPECT using teboroxime was compared to thallium SPECT in 26 patients undergoing cardiac catheterization. Agreement between thallium SPECT and teboroxime SPECT for the identification of myocardial segments was 209/235 (89%). A significant correlation was found in 15 patients between the left ventricular ejection fraction by teboroxime first-pass study and the ejection fraction by contrast ventriculography. In nine patients with myocardial infarction and/or multivessel coronary artery disease, the ejection fraction revealed a mean decrease from 0.52 at rest to 0.46 at exercise. Teboroxime makes it possible to perform an exercise first-pass study of left ventricular ejection fraction followed by myocardial perfusion imaging.

Myocardial single photon emission tomography (SPET) using technetium-99m teboroxime (teboroxime) was studied and the results compared with those of thallium-201(thallium) SPET and coronary arteriography in 19 patients. Resting teboroxime SPET was performed initially. Two hours later, exercise teboroxime SPET was performed. Exercise ergometer tests for both teboroxime and thallium were carried out in a supine position. The levels of exercise achieved for both tests were similar. Agreement for the identification of myocardial segments between thallium SPET and teboroxime SPET was 147/171(86%) (NS). When a significant stenosis was defined as greater than or equal to 75% or greater than or equal to 50%, agreement between two radiopharmaceuticals for the detection of diseased vessels was 89% (NS, k = 0.601) or 88% (NS, k = 0.713), respectively. In only 2/19 cases were inferior and posterior segments (3/171) difficult to interpret in teboroxime SPET due to hepatic activity. Thus, teboroxime SPET with a short data acquisition time resulted in a rapid completion for each study and had a good correlation with thallium SPET.

Tc-99m HMPAO SPECT is more likely to detect a stroke in early stages than CT. However, a conventional HMPAO SPECT study takes at least 30 minutes to complete. This paper compares fast Tc-99m HMPAO SPECT scans and conventional Tc-99m HMPAO SPECT scans with respect to spatial resolution and diagnostic efficacy in vitro and in a small series of patients, respectively. The spatial resolution of fast Tc-99m HMPAO SPECT did not match that of images obtained from conventional SPECT, though the difference proved to be of no clinical significance. Since fast SPECT requires only one-fourth to one-fifth the time necessary for conventional SPECT, it may be more suitable for investigating cases of acute stroke in critical clinical situations.

The first data acquisition method for Tc-99m hexamethylpropyleneamineoxime (Tc-99m HMPAO) brain SPECT was used in two patients with acute stroke 5 and 8 hours after the event. In one patient Tc-99m HMPAO fast SPECT showed perfusion defects before the same was manifested on CT. In the other patient, Tc-99m HMPAO fast SPECT showed larger defects than the edema seen on CT. The Tc-99m HMPAO fast SPECT might be feasible for the evaluation of acute stroke patients. Since the time required for fast SPECT is much shorter than usual SPECT, it appears to be more suitable for some patients with acute stroke who are brought to the hospital in a very critical condition.

A 9-year-old girl had pain and swelling of the left distal thigh for 5 months. Radionuclide angiography of leg arteries was performed using Tc-99m DTPA-HSA. Increased blood pooling was observed in the distal thigh and knee joint area of the left leg 20 minutes after the injection. Open biopsy revealed hemangioma in that area. Blood pool imaging uisng Tc-99m DTPA-HSA is a useful method in the diagnosis of soft tissue hemangioma

This study was performed, i) to compare radionuclide angiocardiography with the other methods, and ii) to evaluate its usefulness in investigating left ventricular performance and its reserve. Radionuclide angiocardiography, chest X-ray film, chest X-ray cinegraphy, echocardiography, two-dimensional echocardiography, pulsed Doppler flowmetry, cardiokymography, myocardial imaging, contrast ventriculography and coronary arteriography were performed (:also at exercise) in 105 subjects including various kinds of cardiac patients. Radionuclide angiocardiography could be performed both at rest and at exercise, contrary to invasive methods. In detailed analysis of left ventricular mechanics in non-ischemic heart disease, echocardiography at rest and at exercise may be appropriate, because of its high image resolution. In evaluation of ischemic heart diseases, radionuclide angiocardiography at rest and at exercise might be appropriate, because of bidirectional informations and its high success rate. Two-dimensional echocardiography with M-mode echocardiography might compensate for it, particularly for continuous informations during exercise. Detection of regional wall motion dysfunction at exercise is more specific than exercise ECG and is more sensitive than exercise myocardial imaging. From many kinds of examinations, appropriate one should be selected according to the purpose of investigators. Much more technical progress in these methods can be expected.

The sensitivity of the commonly used stress tests for the diagnosis of coronary artery disease was analyzed in 46 patients with significant occlusion (greater than or equal to 70% luminal diameter obstruction) of only one major coronary artery and no prior myocardial infarction. In all patients, thallium-201 perfusion imaging (both planar and seven-pinhole tomographic) and 12 lead electrocardiography were performed during the same graded treadmill exercise test and radionuclide angiography was performed during upright bicycle exercise. Exercise rate-pressure (double) product was 22,307 +/- 6,750 on the treadmill compared with 22,995 +/- 5,622 on the bicycle (p = NS). Exercise electrocardiograms were unequivocally abnormal in 24 patients (52%). Qualitative planar thallium images were abnormal in 42 patients (91%). Quantitative analysis of the tomographic thallium images were abnormal in 41 patients (89%). An exercise ejection fraction of less than 0.56 or a new wall motion abnormality was seen in 30 patients (65%). Results were similar for the right (n = 11) and left anterior descending (n = 28) coronary arteries while all tests but the planar thallium imaging showed a lower sensitivity for isolated circumflex artery disease (n = 7). The specificity of the tests was 72, 83, 89 and 72% for electrocardiography, planar thallium imaging, tomographic thallium imaging and radionuclide angiography, respectively. The results suggest that exercise thallium-201 perfusion imaging is the most sensitive noninvasive stress test for the diagnosis of single vessel coronary artery disease.

人工肛門より明瞭な注腸造影を得るために, 内外2筒からなる陰圧型の人工肛門注腸補助器を開発した.これとgyroscopeとの併用により, 直腸癌術後などの人工肛門保有者30例に注腸X線検査を行い, つぎのような利点が判明した.すなわち (1) 残存結腸の完全な二重造影像が得られ,(2) 人工肛門周囲を汚すことなく検査が終了し,(3) 腸管穿孔の心配が全くないことなどである.これらの検査でわれわれの補助器が有用であった症例を紹介し, さらに人工肛門からの高圧浣腸にも応用しているのでその実際について説明した.

The authors have developed a new scanning method for Tl-201 myocardial SPECT using a rotating gamma camera with 180-degree data collection. This requires a new type of imaging table on which the patient is placed in a 50-degree right semidecubital position to allow close proximity to the camera-collimator system. Using this method, attenuation by the imaging table is completely avoidable because the projected views in the left oblique directions are not obstructed by the table. In addition, the radius of camera rotation is about 25% shorter than in the conventional method. Phantom and 16 clinical studies were performed to compare the performance of conventional and semidecubital position methods. In phantom studies, tomographic images produced using the new method showed better lesion contrast and more counts in the posteroinferior wall of the heart than those produced using the conventional method. Clinically, 12 of the 16 studies showed more counts in the posteroinferior wall of the heart with the semidecubital position method than with the conventional method. The semidecubital position method is useful for Tl-201 myocardial SPECT, especially for evaluation of posteroinferior wall hypoperfusion.