An X-ray dosimeter has been investigated with the use of a PROM of a SAMOS (stacked gate avalanche injection type MOS) structure. The SAMOS is employed as a memory IC. The SAMOS is different from a FAMOS (floating gate avalanche injection type MOS) in the presence of a control gate, with the use of this electrode, the analog amount of electrical charge accumulated in the floating gate can be measured. The X-ray dose can be determined by decreasing the amount of electron injected into floating gate by avalanche effect through X-ray irradiation. This dosimeter shows good linearity and flat energy response. The dosimeter has no effect on fading.
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) sareoidosis (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±4.7s in normal subjects, 42.3±16.0s 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.
In order to detect the varicocele, scrotal scintigraphies by using99mTc-HSA-D were performed in 14 patients with male infertile or palpable mass in left scrotum on physical examinations. Abnormal pooling of99mTc-HSA-D, indicative of varicocele lesion, could be found in left scrotum in 9 cases, confirmed surgically or clinically. Compared with99mTc-HSA, 99mTc-HSA-D was superior in high uptake ratio of varicocele to soft tissue and in nonvisualization of bladder. Thus, 99mTc-HSA-D scrotal scintigraphy seemed to be of a great use to detect the varicocele.
A case of giant internal carotid ophthalmic aneurysm was presented. In order to clarify whether the patient could tolerate carotid occlusion, a balloon clamping test was performed before surgery. The cerebral blood flow was measured using early imaging by single photon emission computed tomography (SPECT) with N isopropyl- (iodine-123) -p-iodoamphetamine (123I-IMP) . When the balloon clamping test was performed the tracer was injected, and scaning was performed 35 minutes after removing the catheter. This tracer enabled a“memory of blood flow”during temporary ischemia to determine the character of quick diffusion and slow wash out, that could not be performed by other methods of cerebral blood flow measurement. SPECT with123I-IMP can simplify the measurement of cerebral blood flow during the balloon clamping test.
Bone scintigraphy using99mTc-MDP was performed on 2 patients with Paget's disease of bone before and after the treatment with a synthetic eel calcitonin analogue ( (Asu1, 7) -eel calcitonin, ECT) ) at a dose of 40 U per day. All pagetie lesions showed markedly the increased accumulation of the radionuclide. The uptake ratio, defined as the count rate of99mTc-MDP over each bone lesion to that over the control bone, was calculated. The response to the calcitonin therapy was evaluated with the uptake ratio of the radionuclide. The uptake ratio decreased markedly within the first 3 months of the treatment, in association with a palliation of bone pain, while the serum alkaline phosphatase activities which had been within the normal range or slightly high before the treatment did not show any significant change or did not reflect a clinical feature (e.g, bone pain) with the treatment. Thus, the uptake ratio on the bone scintigram seemed to offer the most sensitive and most reliable information for the evaluation of calcitonin treatment of Paget's disease of bone.
The effect of pixel size on imge quality was investigated. The image quality was examined by abnormality detection and image preference for clinical images displayed with different pixel sizes. Smaller pixel size was found to be superior to large one in image quality using large field of gamma camera (FWHM 6.42 mm), 1.6 mm pixel size (a 256×256 matrix) was found to be the best in image quality. Examined image minification effect, 3.2 mm pixel size (image size: 5 cmφ) was found to be superior to 1.6 mm pixel size (image size: 10 cmφ) in image preference and to be almost equal to 1.6 pixel size in abnormality detection.
An IgE RIA kit (Sandwich method; Dainabott), is used to obtain the following results. (1) Standard curve: Since the range of reproduction rate show 3.16-7.07% (C. V.), the curve become steep. (2) Incubations under controlled situation: Both of the incubations are controlled at 15-30°C for 2 h. (3) Reproducibility test: Coefficients of variation (C. V.) of intra-assay and inter-assay variation are 2.32-3.94% and 2.92-3.92% respectively. (4) Recovery test: A result of the recovery test range between 100.1-101.7%. (5) Dilution test: Multiple dilution effects are observed. (6) Average counts of the serum IgE for the controlled and diseased groups: The average counts of the serum IgE for the controlled group, atopic diseased group, allergic rhinitis group and allergic bronchial asthma are 144.9±183.2 IU/ml, 1099.0± 2782.4 IU/ml, 1150.9±2 063.3 IU/ml and 600.7± 686.4 IU/ml respectively. The value of the diseased groups have tendency to show higher averages than the controlled group. Since the controlled and diseased groups show wide distributions of the serum IgE level, there is no significant difference of two variations. However the diseased groups have tendency to show higher ratio of the serum IgE level in blood than the controlled groups. These basic researches are quite meaningful, because they are able to apply for a supplemental diagnosis of the atopic and parasitic disease.