Increase in collateral arterial endothelial cell proliferation induced by captopril after renal artery stenosis in the rat.

Studies to assess the role of blood pressure rise in the growth of the collateral arterial supply following renal artery stenosis were performed in 70 rats. Assessment of the proliferative response was made by coded reading of endothelial cell turnover following tritiated thymidine administration, 5 days after renal artery stenosis. Stenosis induced the anticipated brisk increase in endothelial cell turnover in arterial collaterals and in the ipsilateral renal vein, and ureteric epithelium. Blood pressure elevation did not appear to play the dominant role, as the proliferative response did not parallel blood pressure changes; moreover, neither bilateral renal artery stenosis, designed to enhance the hypertension, nor hydralazine administration, to reduce the blood pressure, influenced endothelial cell turnover. A contribution of elevated blood pressure to the vasoproliferative response, however, was not ruled out definitively in this study. Captopril, also administered to assess the same question, resulted in an enhanced endothelial cell proliferative response, both in frequency and in degree, an observation that became the central thrust of our study. The mechanism by which converting enzyme inhibitor modified endothelial cell turnover is not clear, but may well provide insight into the responsible factors.

Preparation of a chemically characterized 99mTc-penicillamine complex.

In the reaction labeling penicillamine with 99mTc, serveral different chemical states of 99mTc were observed to occur with slight changes in the labeling conditions, such as the concentrations of penicillamine, 99mTcO4-, stannous chloride, and hydrogen ion. We have studied the effects of these conditions on the formation of the monomer complex that we call Complex I, in which 99mTc is coordinated with the penicillamine as 99mTcO+2. Our approach is based on the thesis that Complex I formation competes with 99mTcO+2 hydrolysis, which leads to other 99mTc complexes. On this basis, the specific labeling conditions for Complex I formation have been established. Highly reproducible in vivo behavior in mice and rats was obtained with this chemically controlled Complex I.

Technetium-99m-kethoxal-bis(thiosemicarbazone), an uncharged complex with a tetravalent 99mTc state, and its excretion into the bile.

Technetium-99m-kethoxal-bis (thiosemicarbazone) complex (99mTc-KTS), a potentially useful radiopharmaceutical for cholescintigraphy, is prepared by the reaction of KTS with 99mTcO4- in the presence of stannous chloride. Under the described conditions, a complex extractable with organic solvent was detected. Thin-layer chromatography, electrophoresis, and spectrometric analysis indicate the formation of an uncharged 99mTc(IV) complex. Organ distribution and biliary excretion studies are described. The complex showed a marked highly reproducible accumulation in the gallbladder.

Two cases of primary isolated chylopericardium diagnosed by oral administration of 131I-triolein.

Two cases of isolated chylopericardium, one idiopathic and the other secondary to the lymphangioma of the pericardium are reported here. In both cases, correct diagnosis was made by radionuclide imaging techniques. When imaging the cardiac pool using 99mTc-in vivo, labeled RBC, a large separation between the heart and surrounding organs was demonstrated; this suggested a presence of massive pericardial effusion. On pericardial imaging taken 24 hours after oral administration of 131I-triolein, a donut-like shape was clearly produced, situated in a gap between the separation, suggesting chylous effusion within the pericardial space. On operating, isolated chylopericardium was confirmed in both cases. To our knowledge, this is the first report of preoperative noninvasive diagnosis of chylopericardium in Japan.

Sonographic diagnosis of biliary ascariasis.

Real-time sonographic imaging can clearly represent the biliary ascarid as a longitudinal double linear echo. We call this representation an intraductal tubular image. Such imaging allows easy differentiation of the biliary parasite from calcification and other foreign bodies in the biliary tracts.

Scintigraphic and MRI studies in a patient with granulocytic sarcoma accompanied with CML and myelofibrosis.

Indium bone marrow, bone, and gallium scans and magnetic resonance imaging (MRI) were performed in a patient with granulocytic sarcoma accompanied with chronic myelocytic leukemia (CML) and myelofibrosis. The significance and implications of the findings of these studies are discussed.

Assessment of magnetic resonance contrast enhancement with Gd-DTPA: comparison with the uptake of Tc-99m-DTPA.

To compare the contrast enhancement of Gd-DTPA with the uptake of 99mTc-DTPA, a study was carried out in two steps. In the first step, images comparable in terms of data acquisition time and thickness were obtained after computer processing, and processed images of 99mTc-DTPA and Gd-DTPA enhanced MRI were compared from the morphological aspect. In the second step, the arterial blood concentration of Gd-DTPA and the effect of T2 shortening on signal intensity were studied. It was concluded that Gd-DTPA enhanced MRI can provide functional information analogous to that obtained from radionuclide studies, possibly enabling semiquantitative analysis of contrast enhancement to be performed.

A study of regional cerebral blood flow and hemodynamics in cerebrovascular diseases by selective continuous infusion of Kr-81m.

A tomographic study of regional cerebral blood flow and hemodynamics was performed on 25 patients with cerebrovascular diseases by selective continuous infusion of krypton-81m (Kr-81m). Kr-81m single photon emission computed tomograms were superimposed on X-ray computed tomograms to assess topographically the perfusion of the entire brain. Study of cerebrovascular diseases using this method showed: (1) regional cerebral blood flow change; (2) perfusion distribution change; (3) the route by which blood reached the brain or the obstructed artery proximal to the circle of Willis; (4) development of a collateral system and its actual function; and (5) efficacy of surgical bypass after extracranial-intracranial anastomosis. This method is especially useful in hemodynamic assessment in patients with ischemic cerebrovascular disease.

Mycotic aneurysm.

Mycotic aneurysms must be diagnosed rapidly because of the high mortality, associated with them. X-ray computed tomography (X-CT) is a noninvasive modality. Intravenous digital subtraction angiography (IVDSA) is also much less invasive and less dangerous than arteriography, especially in mycotic aneurysms, whose wall is thin. We describe two patients with mycotic aneurysms diagnosed by X-CT and IVDSA.

Perinephric xanthogranulomatous pyelonephritis simulating a renal or retroperitoneal tumor on X-ray CT and angiography.

A case of perinephric xanthogranulomatous pyelonephritis is presented. Ultrasonography and X-ray computed tomography (X-CT) showed a mass on the posterior aspect of the right kidney, causing us to suspect right renal cell carcinoma. Pyelography showed a deformity of the right renal calyces. From angiographic results, we considered the possibility of hypovascular renal cell carcinoma, subcapsular tumor, or retroperitoneal tumor. The mass was diagnosed pathologically as perinephric xanthogranulomatous pyelonephritis.

[Transient ischemic dilatation of the left ventricle observed on dipyridamole-stressed thallium-201 scintigraphy].

To assess clinical significance of transient ischemic dilatation of the left ventricle (TID) on dipyridamole-stressed 201Tl myocardial scintigraphy, 110 patients suspected with coronary artery disease, including 13 with normal coronary, 48 with single vessel disease, 30 with 2 vessel disease, and 19 with 3 vessel disease were analyzed. TID was visually and quantitatively assessed calculating the ratio of the area within the left ventricular region on the initial and delayed image (TID ratio). TID was observed in 3 of 1 vessel disease (6%), 5 of 2 vessel disease (17%), and 8 of 3 vessel disease (42%). None of normal coronary artery showed TID. In patients with multivessel disease (MVD), TID was observed more frequently (27%) than in patients with 1 vessel disease (6%) (p < 0.025). Furthermore, the TID ratio tended to be higher (1.15 +/- 0.11) than those with single vessel disease (1.03 +/- 0.03). To identify patients with MVD, TID had a sensitivity of 27% and a specificity of 95%. ECG changes were observed more often in patients with TID than those without TID. Five patients showing TID underwent coronary artery bypass graft surgery, TID disappeared postoperatively in each patient. In conclusion, TID on dipyridamole 201Tl scan seems to be a specific although not sensitive marker for detecting MVD.

[Percutaneous ethanol injection of parathyroid adenoma under US guidance].

A patient with post-operative recurrent parathyroid adenoma was treated with percutaneous injection of absolute ethanol under ultrasonographic guidance. Serum calcium and PTH level were both successfully normalized, while recurrent nerve palsy was encountered as side effect. Six months later, she was suffered from hyperparathyroidism again, because of local tumor recurrence. Her recurrent nerve palsy was cured at that time. This technic could be a simple and non-invasive alternative for the conventional surgical procedure, but the indication for larger adenomas like this case should be carefully considered.

[New devices for non-vascular interventional radiology].

Interventional Radiology (IVR) is a field of medicine, which has made diagnosis or treatment previously performed only by surgery possible percutaneously. For safe and successful IVR, good devices are necessary. Therefore, development of new devices is essential for the progress of IVR. Various kinds of new devices for non-vascular IVR are introduced, including new biopsy needles, AccuStick, Cope Gastrointestinal Suture, Rösch-Thurmond Fallopian Tube Catheterization Set, ESP Glove and others. Most of them are now commercially available in Japan. However, all of them cost much higher than they cost in the USA.