A comparative study of dynamic CT and ultrasonic pulsed Doppler method for estimation of the portal blood flow.

A new dynamic CT method for evaluating the portal blood flow is described. Thirty healthy volunteers were injected with non-ionic hypo-osmotic iodine contrast medium to estimate the portal blood flow. Time density curves (TD-curves) for the abdominal aorta and the main trunk of the portal vein were determined on the basis of data obtained by dynamic CT. From the TD-curves, portal blood flow coefficient and circulation time to flow into the portal vein (P-P time) were calculated. More detailed data of the TD-curves could be obtained by the new dynamic CT than by the previous methods. Subjects were simultaneously studied by an ultrasonic pulsed Doppler method which has been clinically accepted. There was a significant correlation between our dynamic CT method (portal blood flow coefficient) and the ultrasonic pulsed Doppler method concerning the measurement of portal blood flow. Therefore, it may be concluded that this CT method is reliable and clinically acceptable.

[An analysis of regional ventilation in pulmonary sarcoidosis by inspired 133Xe washout test].

Xenon-133 ventilation study were used to measure regional ventilation in seven patients with pulmonary sarcoidosis and in four normal subjects. For the purpose of analyzing the washout curves on the whole lungs, two ventilation indexes were calculated, which were TA/H and T1/2. TA/H is that the area under the curve divided by the difference in mean count rate during equilibrium and at 120 s after washout started. T1/2 value represents the time required to 50% of the mean count rate during equilibrium. The average time of TA/H on the whole lung was 13.5 +/- 1.1 s in normal subjects (n = 4), 13.0 +/- 4.3 s in stage I (bilateral hilar lymphadenopathy without lung involvement on chest X-ray) sarcoidosis (n = 3), 21.3 +/- 1.8 s in stages I, II (lung involvement) sarcoidosis (n = 4). The average time of T1/2 on the whole lung was 43.7 +/- 4.7 s in normal subjects, 42.3 +/- 16.0 s in stagel sarcoidosis, 72.5 +/- 28.6 s stages II, III sarcoidosis. The ventilation indexes on the regional lungs showed almost a similar tendency to that on the whole lung. The ventilation indexes in patients with stage II, III sarcoidosis were significantly longer than in normal subjects and in patients with stage I sarcoidosis. It was suggested that 133Xe washout test might detect regional ventilation abnormalities which were not recognized on chest X-ray in pulmonary sarcoidosis.

[Study of quantitative evaluation of liver volume and accumulation rate of radioactive agent with single photon emission computed tomography].

The quantitative evaluation on measurement of liver volume and the hepatic accumulation rate of the radioactive agent were studied with respect to body constitution, background activity and splenic consumption rate, using single photon emission computed tomography (SPECT). The optical cut-off level for liver volume determination was proved to be reasonable as 35%. The background less than 5% had no influence to their clinical estimation with the error of less than 1.6%. The estimation of liver volume was mostly influenced by the splenic activity. When the splenic activity was increased two times of the hepatic activity, the liver volume was determined as 4.2% larger. Calculated counts by SPECT was well correlated with the hepatic activity. This study proved that SPECT was useful for the quantitative evaluation of the liver volume and the hepatic accumulation rate.

Sputum cytology of a metastatic postradiation sarcoma (malignant fibrous histiocytoma).

A female patient who died of apparent postradiation sarcoma in the inguinal region after irradiating a metastatic squamous cell carcinoma of the same site was reported. For approximately 20 months, the patient had received a total of 6,600 and 9,600 Roentgen to the right para-aortic and inguinal areas, respectively. About 10 years later, she developed a sarcoma, namely a malignant fibrous histiocytoma. Sputum cytology demonstrated numerous giant cells with bizarre nuclei; subsequent chest films also presented apparent metastatic tumor shadows. The cellular characteristics and also rather low incidence of detection of nonepithelial malignant tumor by sputum cytology were briefly discussed, and ways of enhancing cytodiagnostic accuracy were proposed.