• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.282-292
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• 1994

Brain perfusion SPECT shows typical regional perfusion abnormalities in Alzheimer's disease(AD) and is useful for its diagnosis. However, there is also arguement that these patterns show significant overlap with other causes, and the accuracy for SPECT in differentiating AD has shown conflicting results. We postulate that the variation in re-ported results are partly due to a difference in patient or control selection with special reference to the mixture of ischemic cerebral disease in the studied population. To deter-mine the effect of ischemic lesions and the nature of control subjects on SPECT studies for AD, we performed $^{99m}Tc$-HMPAO single photon emission computed tomography (SPECT) in 11 probable AD patients with a low (<4) Hachinski ischemic score and 12 non-demented age matched controls. Magnetic resonance imaging(MRI) disclosed ischemic cerebral lesions in 27% (3/11) of the PAD group and 25% (3/12) of the control group. Regional perfusion indices were quantitated from the SPECT images as follows and the distribution of perfusion indices from both groups were compared. This was repeated with controls after excluding those with significant ischemic lesions by MRI : regional perfusion index = average regional count/average cerebellar count All PAD patients showed perfusion abnormality in SPECT. However, 53% (10/12) of controls also showed perfusion at-normalities, and no pattern could reliably differentiate the two groups. After excluding controls with significant cerebral ischemia, the difference in temporal and parietal perfusion index was increased. A decreased tempore-parietal and any parietal or temporal per-fusion index had a sensitivity of 18% and 36% in detecting AD, respectively. When using a separate group of normal age mathced controls, the indices showed an even more difference in the temporal and parietal lobes and the sensitivity of a decreased tempore-parietal and any parietal or temporal perfusion index had a sensitivity of 36% and 55% in detecting AD, respectively. Thus, the type of control with special reference to the pres-once of ischemic cerebral lesions contribute significantly to the accuracy of perfusion SPECT in diagnosing AD. This nay have particular importance in the diagnosis of AD in populations where the prevalance of cerebrovascular disease is high.

• The Korean Journal of Nuclear Medicine
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• v.28 no.2
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• pp.167-171
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• 1994

Ethylcystein dimer (ECD) was synthesized by dimerizatlon of L-thiazolidine-4-carboxylic acid in liquid ammania with sodium metal and successive esterification in ethanolic solution of hydrogen chlorde. The purified product was labeled with $^{99m}Tc$ in the presence of sodium glucarate(pH= 5.6) and stannous chloride. Best result was obtained from the preparation con sisting of 0.1mg ECD, $40{\mu}l$ of 0.4M sodium glucarate (pH=5.6), and $20{\mu}g$ of stannous chloride. The labeling efficiency was 90% with previous condition. The labeled $^{99m}Tc$-ECD was stable at least for 3 hours in PBS(pH=7.4) at room temperature. About 10mCi of $^{99m}Tc$-ECD was injected to normal volunteer, and SPECT image of brain was obtained by triple head camera 10 minutes after inection. The image showed similar distribution of radioactivity in brain with that of HMPAO image.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.110-117
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• 1995

Tc-99m Labeled hexamethylenepropyleneamineoxime ([$^{99m}Tc$]-HMPAO) is a famous amino-oxime compound and is widely used to construct SPECT images of cerebral blood flow. To investigate the relationship between chemical structure and radiolabeling in these kind of diamine-oxime compounds, we synthesized seven compounds by Schiff's base formation and successive reduction with sodium borohydride. They were (RR/SS )-4,8-diaza-3,6,6,9-tetramethylundecane-2,10-dione bisoxime (2), (RR/SS/meso)-4,8-diaza-3,9-dimethy-lundecane-2,10-dione bisoxime (4), (RR/SS/meso)-4,8-diaza-3,10-dimethyldodecane-2,11-dione bisoxime (5), (RR/SS/meso)-4,7-diaza-3,6,6,8-tetramethyldecane-2,9-dione bisoxime (8), (RR/SS/meso)-4,7-diaza-5,6-cyclohexyl-3,8-dimethyldecane-2,9-dione bisoxime (10), (RR/SS/meso)-3,4-bis(1-aza-2-methyl-3-oxime-1-butyl)-benzoic acid (12), and (RR/SS/ meso)-2,3-bis(1-aza-2-methyl-3-oxime-1-butyl) benzophenone (14). Chemical structures of all the synthesized compounds were identified by taking $^1H$ spectrum. Among them, 2 and 4 are propyleneamine oxime (PnAO), 6 is butyleneamine oxime (BnAO) and 8, 10, 12 and 14 are ethyleneamine oxime (EnAO). Each compound (0.5 mg) was incubated with stannous chloride (0.5 g - 8 g), carbonate-bicarbonate buffer (final concentration = 0.1 M, pH 7 - pH 10) and Tc-99m-pertechenate (1 ml). Tc-99m labeling of these compounds were checked by ITLC (acetone), ITLC (normal saline), reverse phase TLC (50 % acetonitrile) and ITLC (ethyl acetate). According to the results, EnAO's were not labeled by Tc-99m in any of above condition. About 11 % of maximum labeling efficiency was obtained with BnAO. However, 4 (PnAO) was labeled with Tc-99m to 85 % which is similar to the labeling efficiency of 2 (HMPAO). Hydrophilic impurity (9 % ) was the most significant problem with the labeling of 4, however, pertechnetate (3 % ) and colloid (3 %) were minor problem. In conclusion, we synthesized seven diamine blsoxlme compounds. Among them, four EnAO compounds were not labeled by Tc-99m. A BnAO was labeled poorly and two PnAO's were labeled well. These labeling can be explained by tertiary structure of their Tc-99m chelate.

• The Korean Journal of Nuclear Medicine
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• v.36 no.6
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• pp.357-367
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• 2002

Purpose: While cerebral blood flow and cerebrovascular reserve could be evaluated with basal/acetazolamide Tc-99m-HMPAO SPECT in cerebrovascular disease, objective quantification is necessary to assess the efficacy of the revascularization. In this study we adopted the SPM method to quantify basal cerebral blood flow and cerebrovascular reserve on basal/acetazolamide SPECT in assessment of the patients who underwent bypass surgery for linternal carotid artery (ICA) stenosis. Materials and Methods: Twelve patients ($51{\pm}15$ years) with ICA stenosis were enrolled. Tc-99m-HMPAO basal/acetazolamide perfusion SPECT was peformed before and after bypass surgery. After spatia1 and count normalization to cerebellum, basal cerebral blood flow and cerebrovascular reserve were compared with 21 age-matched normal controls and postoperative changes of regional blood flow and reserve were assessed by Statistical Parametric Mapping method. Mean pixel values of each brain region were calculated using probabilistic anatomical map of lobes. Perfusion reserve was defined as the % changes after acetazolamide over basal counts. Results: Preoperative cerebral blood flow and cerebrovascular reserve were significantly decreased in involved ICA territory, comparing with normal control (p<0.05). Postoperative improvement of cerebral blood flow and cerebrovascular reserve was observed in grafted ICA territories, but cerebrovasculr reserve remained with significant difference with normal control. Improvement of the cerebrovascular reserve was most prominent in the superior temporal and the angular gyrus, nearest to the anastomosis sites. Conclusion: Using SPM quantification method on hasal/acetazolamide Tc-99m-HMPAO SPECT, the cerebral blood flow and cerebrovascular reserve could be assessed before revascularization and so could the efficacy of the bypass surgery.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.1
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• pp.15-22
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• 2017

Purpose During Brain SPECT study, critical factor for proper study with $^{99m}Tc-ECD$ or $^{99m}Tc-HMPAO$ is one of the important causes to patent's movement. It causes both improper diagnosis and examination failure. In this study, we evaluated the effect of Dynamic Continuous Mode Acquisition compared to Step and Shoot Mode to raise efficacy and reject the data set with movement, as well as, be reconstructed in certain criteria. Materials and Methods Deluxe Jaszczak phantom and Hoffman 3D Brain phantom were used to find proper standard data set and exact time. Step and Shoot Mode and Dynamic Continuous Mode Acquisition were performed with SymbiaT16. Firstly, Deluxe Jaszczak phantom was filled with $Na^{99m}TcO_4$ 370 MBq and obtained in 60 minutes to check spatial resolution compared with Step and Shoot Mode and Dynamic Continuous Mode. The second, the Hoffman 3D Phantom filled with $Na^{99m}TcO_4$ 74 MBq was acquired for 15 Frame/minutes to evaluate visual assessment and quantification. Finally, in the Deluxe Jaszczak phantom, Spheres and Rods were measured by MI Apps program as well as, checking counts with the frontal lobe, temporal lobe, occipital lobe, cerebellum and hypothalamus parts was performed in the Hoffman 3D Brain Phantom. Results In Brain SPECT Study, using Dynamic Continuous Mode rather than current Step and Shoot Mode, we can do the reading using the 20 to 50 % of the acquired image, and during the test if the patient moves, we can remove unneeded image to reduce the rate of restudy and reinjection. Conclusion Dynamic Continuous Mode in Brain study condition enhances effects compared to Step and Shoot Mode. And also is powerful method to reduce reacquisition rate caused by patient movement. The findings further indicate that it suggest rejection limit to maintain clinical value with certain reconstruction factors compared with Tomo data set. Further examination to improve spatial resolution, SPECT/CT should be the answer for that.

• 대한핵의학회:학술대회논문집
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• 1990.04a
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• pp.184-184
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• 1990

• 대한핵의학회:학술대회논문집
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• 1989.06a
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• pp.120.2-120.2
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• 1989

• 대한핵의학회:학술대회논문집
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• 1988.05a
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• pp.123.1-123.1
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• 1988

• 대한핵의학회:학술대회논문집
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• 1987.05a
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• pp.126.2-127
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• 1987

• 대한핵의학회:학술대회논문집
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• 1991.05a
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• pp.143-144
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• 1991