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ABSTRACT: To analyze the retention process of technetium-99m ethyl cysteinate dimer (99mTc-ECD) in normal and ischemic lesions, we developed a super rapid dynamic SPECT system based on the CERASPECT (DSI, Inc.,
Waltham, MA, USA). The system made it possible to take a SPECT series every 2 seconds. Each SPECT series contains a maximum
of 16 slices (6.6 mm slice interval) in a matrix size of 32 ? 32. The sensitivity of this system is 175 kcps/MBq/ml/cm slice
thickness, and resolution is 12 mm FWHM at the center of a 20x0444; water phantom.
Using the super rapid SPECT system, the kinetic behavior of the99mTc-ECD during retention in normal and ischemie lesions was analyzed. Twenty patients with ischemie lesions that were clearly
demonstrated by133Xe-rCBF (regional cerebral blood flow) SPECT but unclear on static “Tc-ECD SPECT were examined. For the dynamic SPECT, 700
MBq of ““Tc-ECD was injected intravenously, and dynamic SPECT data were acquired every 2 seconds during a 90-second period.
The serial dynamic SPECT and time-activity curves at some lesions with reduced rCBF and at the contralateral normal brain
were analyzed. These dynamic SPECT data were compared with conventional static99mTc-ECD SPECT and quantitative133Xe-rCBF SPECT.
All of mildly or moderately reduced rCBF lesions on the133Xe-rCBF SPECT were recognized as low activity regions only at the early phase (during about 2-20 sec or less), with the lesions
then gradually vanishing. These lesions were not recognized on the conventional static SPECT taken after the dynamic study.
The time-activity curve at the reduced rCBF lesion was lower than that of contralateral normal brain at the early phase, and
overtook the activity in the normal region with a gradual increase.
The early phase images of99mTc-ECD SPECT within 20 seconds by the super rapid dynamic SPECT were very useful to the same extent as the133Xe-rCBF SPECT for detecting mild or moderate ischemie lesions.
This study suggests that esterase activity, participating in the ECD retention mechanism, may be tolerable to mild or moderate
ischemia. This tolerance may be the main cause of the nonlinear relationship between ECD accumulation and cerebral blood flow.
Annals of Nuclear Medicine 04/2012; 18(6):489-494. · 1.50 Impact Factor
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ABSTRACT: ObjectivesThe aim of this study was to determine the time-activity curve in the cardiac and hepatic region by99mTc-GSA dynamic SPECT which is clinically used in liver scintigraphy and evaluate the temporal changes in the consistency and
errors at the absolute scale using the regression equation of changes in the blood concentration of99mTc-GSA.
MethodsIn 11 patients who underwent99mTc-GSA dynamic SPECT over the 30 min period after IV injection, the percentages of activity in the collected blood and in
the blood pool estimated by dynamic SPECT were determined as the plasma clearance by blood collection and as the blood clearance
by cardiac pooling. Extrahepatic uptake, expressesd as 100 - (% uptake in the liver by dynamic SPECT (%)) was calculated as
the blood clearance by the liver. The regression equation(Y = Yo + Aeat was determined from the changes in the counts, expressed as a percent. Percent errors and the differences in theY-intercept (Yo), coefficient(A) and slope (α) on the regression curve were compared.
ResultsBlood pool clearance gradually exceeded the measured plasma clearance. The clearance by the liver started from a very low
initial value and gradually became equal to that of plasma clearance over the first 15 minutes and exceeded it over the second
15 minutes. TheY-intercept was significantly higher in the blood pool clearance than that in the measured plasma clearance (p < 0.001), and
the coefficient was significantly lower in the former than the latter (p < 0.001). The coefficient and slope were significantly
lower in the hepatic clearance than the plasma clearance (p < 0.001, p < 0.005).
ConclusionThe time-activity curve of the blood pool showed a tendency towards overestimation in the second half of the examination,
probably due to scatter effect from the liver. The time-activity curve of liver uptake showed a tendency towards overestimation
in the first half of the examination, probably due to the high concentration in the hepatic blood pool, and underestimation
in the second half.
Annals of Nuclear Medicine 04/2012; 20(4):295-301. · 1.50 Impact Factor
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Psychiatry and Clinical Neurosciences 03/2008; 46(2):570 - 570. · 2.13 Impact Factor
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ABSTRACT: This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2006 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 975 institutions among 1263 to which the questionnaire had been sent. Thirty-two cases of adverse reactions were reported. A total of 1,189,127 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 2.7. Three cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.3.
Kaku igaku. The Japanese journal of nuclear medicine 03/2008; 45(1):19-35.
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ABSTRACT: This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals in FY2005 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 1,007 institutions among 1,243 to which the questionnaire had been sent. Nineteen cases of adverse reactions were reported. A total of 1,264,098 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 1.5. Three cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.2.
Kaku igaku. The Japanese journal of nuclear medicine 03/2007; 44(1):29-42.
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[show abstract]
[hide abstract]
ABSTRACT: The aim of this study was to determine the time-activity curve in the cardiac and hepatic region by 99mTc-GSA dynamic SPECT which is clinically used in liver scintigraphy and evaluate the temporal changes in the consistency and errors at the absolute scale using the regression equation of changes in the blood concentration of 99mTc-GSA.
In 11 patients who underwent 99mTc-GSA dynamic SPECT over the 30 min period after IV injection, the percentages of activity in the collected blood and in the blood pool estimated by dynamic SPECT were determined as the plasma clearance by blood collection and as the blood clearance by cardiac pooling. Extrahepatic uptake, expressesd as 100--(% uptake in the liver by dynamic SPECT (%)) was calculated as the blood clearance by the liver. The regression equation (Y = Y0 + Ae(-alphat)) was determined from the changes in the counts, expressed as a percent. Percent errors and the differences in the Y-intercept (Y0), coefficient (A) and slope (alpha) on the regression curve were compared.
Blood pool clearance gradually exceeded the measured plasma clearance. The clearance by the liver started from a very low initial value and gradually became equal to that of plasma clearance over the first 15 minutes and exceeded it over the second 15 minutes. The Y-intercept was significantly higher in the blood pool clearance than that in the measured plasma clearance (p < 0.001), and the coefficient was significantly lower in the former than the latter (p < 0.001). The coefficient and slope were significantly lower in the hepatic clearance than the plasma clearance (p < 0.001, p < 0.005). Conclusion: The time-activity curve of the blood pool showed a tendency towards overestimation in the second half of the examination, probably due to scatter effect from the liver. The time-activity curve of liver uptake showed a tendency towards overestimation in the first half of the examination, probably due to the high concentration in the hepatic blood pool, and underestimation in the second half.
Annals of Nuclear Medicine 05/2006; 20(4):295-301. · 1.50 Impact Factor
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Masahiro Koide,
Kazuki Ito,
Takuya Taniguchi,
Hirokazu Yokoi,
Reo Nakamura,
Hidekazu Irie,
Noriyuki Kinoshita,
Tetsuo Hashimoto,
Shunichi Tamaki,
Takahisa Sawada, [......],
Hiroaki Matsubara,
Yuko Kawai,
Koh Kishino,
Kiyoko Kusakabe,
Terue Okamura,
Kanji Kasagi, Akio Komatani,
Yukimitsu Sato,
Hiroshi Matsuda,
Hirotaka Maruno
Annals of Nuclear Medicine 05/2006; 20(3):253-254. · 1.50 Impact Factor
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ABSTRACT: This survey was performed in order to investigate the incidence of adverse reactions to radiopharmaceuticals and defect products in FY2004 in Japan. It was based on responses to questionnaires sent to nuclear medicine institutions. The reply was obtained from 968 institutions among 1,220 to which the questionnaire had been sent. Sixteen cases of adverse reactions were reported. A total of 1,277,906 radiopharmaceutical administrations was reported. The incidence of adverse reactions per 100,000 cases was 1.3. Eight cases of defect products were reported, and the incidence of defect products per 100,000 cases was 0.6.
Kaku igaku. The Japanese journal of nuclear medicine 03/2006; 43(1):23-35.
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[show abstract]
[hide abstract]
ABSTRACT: To analyze the retention process of technetium-99m ethyl cysteinate dimer (99mTc-ECD) in normal and ischemic lesions, we developed a super rapid dynamic SPECT system based on the CERASPECT (DSI, Inc., Waltham, MA, USA). The system made it possible to take a SPECT series every 2 seconds. Each SPECT series contains a maximum of 16 slices (6.6 mm slice interval) in a matrix size of 32 x 32. The sensitivity of this system is 175 kcps/MBq/ml/cm slice thickness, and resolution is 12 mm FWHM at the center of a 20 cm(phi) water phantom. Using the super rapid SPECT system, the kinetic behavior of the 99mTc-ECD during retention in normal and ischemic lesions was analyzed. Twenty patients with ischemic lesions that were clearly demonstrated by 133Xe-rCBF (regional cerebral blood flow) SPECT but unclear on static 99mTc-ECD SPECT were examined. For the dynamic SPECT, 700 MBq of 99mTc-ECD was injected intravenously, and dynamic SPECT data were acquired every 2 seconds during a 90-second period. The serial dynamic SPECT and time-activity curves at some lesions with reduced rCBF and at the contralateral normal brain were analyzed. These dynamic SPECT data were compared with conventional static 99mTc-ECD SPECT and quantitative 133Xe-rCBF SPECT. All of mildly or moderately reduced rCBF lesions on the 133Xe-rCBF SPECT were recognized as low activity regions only at the early phase (during about 2-20 sec or less), with the lesions then gradually vanishing. These lesions were not recognized on the conventional static SPECT taken after the dynamic study. The time-activity curve at the reduced rCBF lesion was lower than that of contralateral normal brain at the early phase, and overtook the activity in the normal region with a gradual increase. The early phase images of 99mTc-ECD SPECT within 20 seconds by the super rapid dynamic SPECT were very useful to the same extent as the 133Xe-rCBF SPECT for detecting mild or moderate ischemic lesions. This study suggests that esterase activity, participating in the ECD retention mechanism, may be tolerable to mild or moderate ischemia. This tolerance may be the main cause of the nonlinear relationship between ECD accumulation and cerebral blood flow.
Annals of Nuclear Medicine 10/2004; 18(6):489-94. · 1.50 Impact Factor
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ABSTRACT: A patient with bilateral diminished visual acuity and blurred vision was given the diagnosis of psychogenic visual disturbance after extensive psychiatric and ophthalmological examinations. Single photon emission computed tomography with Tc-99m-ethylcysteinate dimer demonstrated remarkably reduced regional cerebral blood flow (rCBF) in the bilateral occipital lobes. More specifically, rCBF was reduced in the visual association areas, but not in the primary visual areas. These findings suggest that functional suppression of the visual association area is associated with the development of psychogenic visual disturbance.
Psychiatry Research 08/2002; 114(3):163-8. · 2.52 Impact Factor
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ABSTRACT: 1.1.A 78-year-old female with DDST and pain disorder was treated by clomipramine 20–100 mg/day. The hypochondriacal delusion was completely resolved, while the pains were partially resolved.2.2.The SPECT using Xe-133 taken at the early stage of clomipramine treatment, when she still had hypochondriacal delusions, showed markedly reduced rCBF in the temporal and parietal lobes, with predominance on the left hemisphere. Meanwhile, the SPECT taken after resolution of the hypochondriacal delusions showed a marked improvement in the reduced rCBF.3.3.This report suggests that DDST has some association with reduced rCBF in the temporal and parietal lobes.
Progress in Neuro-Psychopharmacology and Biological Psychiatry.
