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Thorotrast amount deposited in patients, chiefly in the liver and the spleen, was determined with a NaI detector and a Computerised Axial Tomography (CT). In the measurement of the gamma-rays with the NaI detector, the geometry-factors, that are the distance from the detector to the source, the attenuation of the gamma-rays in the tissue and the shapes of the liver and the spleen, were studied, and the mean amount deposited in the organs was determined. In the measurement with CT, the relationship of CT-Number and the amount of thorium was got, and the localized amount and the distribution in the organ were measured.

It is well known that patients with pseudo (PHP)- and idiopathic (IHP) hypoparathyroidism are frequently associated with intracranial calcifications. The relative sensitivity of computed tomography (CT) and conventional skull radiography in detecting basal ganglia calcifications was studied in two patients with PHP and six with IHP. CT was more sensitive: the detection rate was 71% (5/7) for CT and 14% (1/7) for skull radiography. Furthermore, patients with more prolonged hypocalcemia showed a higher incidence of calcifications. Thus, CT was useful as a diagnostic technique in the early detection of calcified basal ganglia.

A false aneurysm of the left ventricle is an uncommon and usually fatal condition, although sometimes it may be successfully repaired with surgery. This report describes two cases of false left ventricular aneurysms detected by first-pass radionuclide ventriculography. The aneurysmal chamber with a small neck giving a characteristic hourglass configuration to the ventricle was clearly demonstrated in these cases. Contrast ventriculography showed similar findings. Cross-sectional echocardiography revealed the characteristics of the false aneurysm in the second case, but was unsuccessful in the first due to pulmonary emphysema. The first patient unfortunately died of a rupture of the false aneurysm but the second patient was treated successfully with surgery. Because of the marked tendency of false aneurysms to rupture, early and safe diagnosis is desirable. Therefore, when a patient shows signs of a left ventricular aneurysm, radionuclide angiography is recommended to differentiate false and true aneurysms non-invasively.

Gated cardiac blood pool scan and hemodynamic parameters by Swan-Ganz catheter were simultaneously measured in five normal subjects (Group A), five patients with coronary artery disease (CAD) without angina on exercise (Group B) and nine patients with CAD with angina on exercise (Group C) in order to evaluate left ventricular function at rest and during supine bicycle ergometer exercise. Work load was gradually increased every 3 minutes and each data were acquired using a digital computer. There was a fairly good correlation (r = 0.83) between stroke volume by thermodilution method and stroke counts corrected by counts/ml of blood on gated cardiac blood pool scan, which were obtained by subtraction of end-systolic counts (ESC) from end-diastolic counts (EDC) in the region of interest arranged at the left ventricle. Stroke counts obtained by this method are considered to reflect a change in the left ventricular volume during exercise. As to the correlation between pulmonary capillary wedge pressure (PCWP) and stroke work index (SWI) at peak exercise, there was a large increase in SWI (78.9 +/- 17.6 to 112.3 +/- 30.0 g X m/m2) with a small rise in PCWP (10.0 +/- 1.9 to 16.2 +/- 4.0 mmHg) in Group A. In Group B, SWI was increased (57.8 +/- 15.8 to 92.9 +/- 25.2 g X m/m2) with a moderate rise in PCWP (11.8 +/- 3.7 to 20.0 +/- 3.1 mmHg) at peak exercise. In Group C, there was a trivial increase in SWI (74.0 +/- 16.0 to 81.2 +/- 29.3 g X m/m2) despite a marked rise in PCWP (13.1 +/- 3.1 to 33.4 +/- 8.9 mmHg). Similar relationship was present between SWI and EDC. On mild exercise of 25w, however, the rise in PCWP was more prominent rather than the increase in EDC in Group C. This indicates that the left ventricle in Group C is operating on a very steep portion of the diastolic pressure-volume curve.

Considering the favourable nuclear properties of 99Tcm over 67Ga, we have developed a new tumour-seeking agent, 99Tc(V)m dimercaptosuccinic acid (Tc(V)-DMSA). In order to evaluate the clinical usefulness of Tc(V)-DMSA scintigraphies, 492 patients were studied with Tc(V)-DMSA, and in some cases, where possible, the results were compared with conventional 67Ga citrate scintigraphies. There was a high degree of usefulness of Tc(V)-DMSA in patients with head and neck tumours, medullary thyroid carcinomas and soft tissue tumours. But in patients with carcinomas of the lung, liver and gastrointestinal tract, malignant melanoma and lymphoma, Tc(V)-DMSA was of no or little use.

Serum CA125, CEA, AFP, LDH levels and LDH isoenzymes were analyzed in ovarian tumor patients, who were treated at Kyoto University Hospital. CA125 was positive in 10/16 (62.5%) cases of common epithelial carcinoma, especially 100% positive in serous carcinoma, but was negative in mucinous tumors. CA125 was also negative in patients with germ cell and sex cord stromal tumors. CEA was positive in 13/32 (40.6%) cases of epithelial carcinoma, most frequently elevated in patients with mucinous carcinoma, pseudomyxoma peritonei, and Krukenberg tumor. AFP was positive only in those with endodermal sinus tumors. LDH was elevated in 16/39 (41%) cases of epithelial carcinoma, but was not specific for histological types. In contrast, all 8 cases of dysgerminoma, 1 of immature teratoma and 2 of endodermal sinus tumor showed extremely elevated LDH levels. Moreover, the normal pattern or deviation to H subunit of LDH isoenzymes was seen in such cases of germ cell tumor, while deviation to M subunit was noted in epithelial and metastatic tumor patients. These data indicate that each parameter is useful as a tumor marker for the specific histological type of ovarian tumor; CA125 for non-mucinous epithelial carcinoma, CEA for mucinous tumor and Krukenberg tumor, AFP for yolk sac tumor, LDH and LDH isoenzymes for dysgerminoma and other solid germ cell tumors. In addition, preoperative diagnosis of histological types of ovarian tumors may be possible by combining these tumor markers.

Indium-111-(111In) labeled monoclonal antibodies (Ab) prepared with a bifunctional chelating agent, diethylenetriaminepentaacetic acid (DTPA), have been used for the radioimmunoimaging of cancer. In the present experiment, using monoclonal Ab against human alpha-fetoprotein (AFP) as a model, we have studied the effect of DTPA conjugation on the antigen binding activity and the biodistribution in nude mice transplanted with AFP-producing human testicular tumor. In Ab heavily conjugated with DTPA, the Scatchard plot analysis demonstrated that the maximum binding capacity rather than the affinity constant was affected. Under selected conditions, 111In-labeled Ab were made available with almost full retention of the antigen binding activity and scintigrams of nude mice clearly delineated the site of the tumor. However, the number of DTPA molecules incorporated per Ab molecule markedly influenced the in vivo biodistribution as well as the in vitro antigen binding activity.

Local cerebral blood flow (CBF) and oxygen metabolism were studied before and after drip infusion of glycerol in seven patients and two normal volunteers.