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Seiji Kawamura,
Shigehiro Fukushima,
Yukiyasu Yoshinaga,
Hidemichi Kawata,
Hisao Miura,
Teruo Miyagawa,
Yoshifumi Fukudome,
Noriyoshi Umezaki,
Masatoshi Ishibashi, Seiichiro Morita,
Naofumi Hayabuchi
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ABSTRACT: The temporal image subtraction technique was applied to bone scintigraphy, using Photoshop (commercially available image processing software) and Morpher (public domain warping software). For the temporal subtraction images, 81 subtraction images (19 cases) were prepared by a method used to subtract the previous images from the current ones. Registration of the current and previous images was performed by manual operation using Photoshop, and warping was done using the warping function of Morpher. In addition, difference images prepared after correcting the distributions of radioactive isotopes of the current and previous images using the count of the pelvic region were also examined. Compared with manual operation, alignment of images by warping improved registration and reduced the generation of pseudo-images of subtraction images. The rate of identification of abnormal accumulation-enhanced regions and subjective evaluation by doctors was improved for warping more than for manual operation. Furthermore, abnormal hot regions, which are difficult to find in film images, could be found in three subtraction images. In addition, it was confirmed that abnormal hot regions become more visible in many cases by preparing subtraction images after correcting the count between images using the count of the pelvic region. Thus, it is suggested that the temporal image subtraction technique in bone scintigraphy enables more accurate observation of enhancement of or changes in abnormal hot regions, which will support diagnostic reading. It is considered that enhancement of or changes in abnormal hot regions will be more accurately understood through further detailed discussion in the future.
Nippon Hoshasen Gijutsu Gakkai zasshi 08/2005; 61(7):997-1005.
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Nippon Hoshasen Gijutsu Gakkai zasshi 03/2004; 60(2):299-302.
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ABSTRACT: Radioactivity after administration of123I-sodium iodide was measured in breast milk samples obtained from a patient with postpartum thyroiditis. The breast milk was
collected over 93 h during the infant’s regular feeding times. The radioactivity in the breast milk was calculated with a123I capsule of the same lot number as the standard source.123I was excreted exponentially with an effective half-life of 5.5 h; 2.5% of the total radioactivity administered was excreted
in the breast milk over the 93 h, 95% of which was excreted within the first 24 h, and 98.2% within 36 h.
The first milk sample collected at 7 h after administration of the radiopharmaceutical contained 48.5% of the total radioactivity
excreted. We estimated the potential absorption of radioactivity to an infant’s thyroid in uninterrupted breast-feeding to
be 30.3 mGy. With a 24-hour interruption, the absorbed radioactivity would be 1.25 mGy; with a 36-hour interruption, it would
be 0.24 mGy.
According to our calculations, breast feeding should be curtailed for 36 h to reduce the infant’s exposure to123I radioactivity. By using a correction factor based on maximum radioactivity from another123I capsule of the same lot, we were able to ascertain the appropriate protocol for our patient and establish a measurement
method that can be applied in similar clinical situations.
Annals of Nuclear Medicine 04/1998; 12(5):303-306. · 1.50 Impact Factor
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ABSTRACT: The renal circulation of patients with essential hypertension and renovascular hypertension was evaluated using 99mTc-DTPA. The first renal peak count (the first Cmax; FCmax), time phase distribution (the first Tmax; FTmax), and blood velocity (the FCmax/FTmax) were calculated by digital imaging. This yields a visual image of the renal circulation. We consider that the increase in the renal first pass blood flow in patients with essential hypertension is best observed pixel by pixel. The FCmax and FCmax/FTmax images before and after treatment by percutaneous transluminal renal angioplasty in patients with renovascular hypertension clearly show its therapeutic effect. The FI technique, therefore, has the advantage that it can be performed at the same time as the conventional routine examinations of renal function. This makes it very useful clinically.
European journal of nuclear medicine and molecular imaging 03/1988; 14(1):25-27. · 4.99 Impact Factor
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ABSTRACT: The heart-to-liver (H/L) uptake ratio in rats was determined 8 min after the rectal administration of 201Tl. Apart from normal controls, three groups of rats were examined; these were composed of animals with induced (1) acute hepatic damage, (2) liver cirrhosis, and (3) partial portal-vein ligation. After the rectal administration of 201Tl, 51Cr-labeled microspheres were injected into the spleen. The radioactivity of the removed liver, lungs, and heart was determined in a gamma-well scintillation counter, and the radioactivity of 201Tl and the 51Cr-labeled microspheres was separately calculated using simultaneous equations derived from the results of a preliminary experiment. The H/L ratios (201Tl) in the normal controls and the animals with acute hepatic damage were not significantly different; however, there was a positive correlation (P0.01) between the H/L ratio and the shunt index (51Cr microspheres) in three groups, i.e., normal controls, liver cirrhosis, and partial portal-vein ligation.
European journal of nuclear medicine and molecular imaging 11/1985; 11(8):316-318. · 4.99 Impact Factor
