• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.116-123
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• 1992

$^{123}I$ has ideal half life of 13 hours, suitable 159 keV gamma energy for imaging, and easy labeling methods. In Korea Cancer Center Hospital, $^{123}I$ has been produced by MC-50 cyclotron. The purpose of this study is looking for good labeling condition of $^{123}I$ and $^{99m}Tc$ to nonspecific human polyclonal IgG, and comparing these with $^{67}Ga-citrate$ in the abscess bearing mice. Human polyclonal nonspecific IgG was labeled with 0.2 M phosphate buffer added $^{123}I$ by chloramine T method. Human polyclonat nonspecific IgG was labeled with $^{99m}Tc-gluconate$ after activation with $\beta-mercaptoethanol$. In the abscess bearing mice, the radioactivity in the abscess was higher in 24 hours than 6 hours after injection. In the abscess, $^{123}I$ nonspecific IgG had higher uptake than $^{99m}Tc-IgG\;or\;^{67}Ga-citrate$. There was no significant difference in absecess uptake of $^{123}I-IgG$ among 24, 72, 120 hours abscess age. Further clinical researches with $^{123}I-nonspecific$ IgG, and other immunoscintigraphies using $^{123}I$ are expected.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.147-148
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• 2010

Introduction: A metastatic calcification is known for taking in bone scintigram medicine at metastatic calcification lesion due to abnormal distribution of the calcium and phosphorus. The one paper reports that a metastatic calcification occurs mainly at lung, stomach, kidney and myocardium. Index: The patient is seventy four years old man who is afflicted with clonic kidney disease, hypercalcemia, hypertension. Because of an ability of the multiple myeloma, we take a bone scan after intravenous injection $^{99m}Tc$-DPD 25 mCi in three hours. We found out homogeneous $^{99m}Tc$-DPD uptake at both lung and myocardium. Conclusions: Nothing unusual was found in other bone scan. We obtains a purity beyond 95 percent at $^{99m}Tc$-DPD vial. In spite of no evidence about a myocardial infarction, the patient has a $^{99m}Tc$-DPD uptake at both lung and myocardium.

• Journal of Biomedical Engineering Research
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• v.16 no.2
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• pp.231-238
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• 1995

Tc-99m-MIBI (Sestamibi) myocardial SPECT along with TI-201 tomographic Imaging has demonstrated wide application and high image quality sufficient for the diagnosis of myocardial perfusion defect, which consequently reflects regional myocardial blood flow. The qualitative values of myocardial SPECT with Tc-99m-MIBI as well ds the quantitative cases depend in some degree on the reconstruction techniques of multiple projections. Filtered backprojection (FBP) Is the common standard method for reconstruction rather than the complicated and time-consuming arithmetic methods. In FBP it is known that the distribution of radioactivity in reconstructed transverse slices varies with the selected litter parameters such as cutoff frequencies and order (Butterworth case) The cutoff frequencies used in clinicAl practice partially remove and decrease the true radioactive distribution and alter the pixel counts, which lead to underestimation of true counts in specific myocardial regions. In this study, we have investigated the effect of cutoff frequencies of reconstruction filter on the artifactually induced perfusion defects, which are often demonstrated near inferior and/or inferoseptal cardiac walls due to the intense hepatic uptake of Tc-99m-MIBI. A computerized method for Identifying the relative degree of artifactual perfusion defect and for comparing those degrees along with the relative amount of hepatic uptake to myocardium was developed and patient images were studied to observe the quantitative degree of underestimation of myocardial perfusion, and to propose some reasonable threshold of cutoff frequency in the diagnosis of perfusion defect quantitatively. We concluded that from the quantitative viewpoint cutoff frequencies may be used as high as possible with the sacrifice of homogeneity of image quality, and those frequencies lower than the common 0.3 Wyquist frequency would reveal severe degradation of radioactive distribution near inferior and/or inferoseptal myocardium when applying Butterworth or low pass filter.

• Journal of radiological science and technology
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• v.32 no.2
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• pp.153-160
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• 2009

In this study, we investigated utility of ultrasonography for urinary tract infections of infants. The results of the research is as follows : 1. The number of infants under one year old was 100 out of 122 infants who were diagnosed as a unitary infection. The ratio of males to females was 1.7 : 1. Seventy-seven infants who underwent three kinds of radiologic examinations such as kidney sonography (51%), $^{99m}TC$ DMSA-scan (42%), and VCUG (22%). 2. In comparison of correlation between kidney sonography and VCUG, the sensitivity of kidney sonography was 82% while the specificity of kidney sonography was 58%. In comparison of correlation between kidney sonography and $^{99m}TC$ DMSA-scan, the sensitivity of kidney sonography was 66% while the specificity of kidney sonography was 67%. 3. Utility of kidney sonography showed the highest efficiency when we considered pain, discomfort, a sense of shame, psychological stress when infants may undergo at the examination, side-effect of a contrast agent after the examination, and complication of exposure to radiation.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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• pp.48-54
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• 2009

Purpose: There are few studies evaluating the usefulness of dedicated high-resolution scintimammography and no studies using delayed washout with this dedicated high resolution scintimammography for the evaluation of breast lesions. We underwent this study to evaluate the clinical usefulness of Tc-99m MIBI in evaluating patients with palpable breast lesions using dedicated high-resolution scintimammography. Materials and Methods: This study included 19 patients with 23 palpable breast lesions who underwent mammography. Tc-99m MIBI was taken to further characterize these lesions. Scintimammography images were acquired with standard craniocaudal and mediolateral oblique views and delayed images were additionally taken. Final conclusions were based on histopathology, either by biopsy or mastectomy results. Results: Eighteen lesions were malignant and five were benign. Mammography was indeterminate for thirteen lesions, nine of those were malignant. Mammography also categorized one lesion as benign in a dense breast, but scintimammography and pathology results showed malignancy. Of the five benign lesions, two were visible on scintimammography, but delayed images showed washout. Conclusion: Based on our preliminary results, dedicated high resolution scintimammography seems to be very useful in characterizing palpable lesions that were indeterminate or negative on mammography.

• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.314-324
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• 1998

Purpose: This study was performed to evaluate the outcome of encephalo-duro-arterio-synangiosis (EDAS) surgery with rest/acetazolamide Tc-99m HMPAO SPECT in moyamoya disease. Materials and Methods: Rost/acetazolamide subtraction SPECT with consecutive acquisition were done before and 2 months after 21 EDAS surgeries in 18 patients. Perfusion decrease was graded visually for 14 areas of each hemisphere as 0 (normal) to 3 (defect) using 4 point scoring system. Postoperative rest perfusion or perfusion reserve was compared with preoperative ones. Results: Among 294 areas of 21 hemispheres, rest perfusion abnormality was found in 91 areas of 15 hemispheres. Decrease of perfusion reserve was found in 146 areas of 18 hemispheres. Six hemispheres having normal rest perfusion and 12 of 15 hemispheres having rest perfusion abnormality showed reserve decrease. Three having rest perfusion defect did not change after acetazolamide in preoperative SPECT. After operation, 16 patients (89%) demonstrated clinical improvement. Fifteen among 18 hemispheres (83%) with decreased reserve improved. Rest perfusion abnormality improved in 6 among the 15 hemispheres (40%). The areas having rest perfusion and/or reserve decrease improved in 87 among 146 areas (60%). Decrease of reserve, improved in 85% (68/80). However, areas without reserve decrease also improved in 29% (19/66). The better was preoperative rest perfusion in involved areas or the more decreased vascular reserve, the more improved perfusion and reserve after operation. Conclusion: We conclude that assessment of perfusion and Perfusion reserve using rest/acetazolamide brain perfusion SPECT predict the surgical outcome in patients with moyamoya disease.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.125-132
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• 1995

The purpose of this study was to establish mononuclear cell cultures such as lymphocytes or buffy coat for the biological dosimetry of in vitro Irradiation of the radionuclide Tc-99m in order to exclude the effect of residual doses seen in the cultures of whole blood. Biological do simetry of Tc-99m on cultured mononuclear cells at doses ranging from 0.05 to 6.00 Gy, by scoring unstable chromosomal aberrations(Ydr) observed in cultured lymphocytes, were performed using peripheral venous blood of healthy normal person. The results showed that; (1) In vitro irradiation of radioisotope in separated lymphocyte or buffy coat showed trace amount of residual doses of isotope after washing. Residual doses of isotopes are increased in proportion to exposed time and irradiated dose without difference between I-131 and Tc-99m. (2) We obtained these linear-quadratic dose response equations in lymphocyte and buffy coat culture after in vitro irradiation of Tc-99m, respectively (Ydr = 0.001949 $D^2$ +0.006279D + 0.000185; Ydr= 0.002531 $D^2$-0.003274 D+0.003488). In conclusion, the linear quadratic dose-response equation from in vitro irradiation of Tc-99m with lymphocyte and buffy coat culture was thought to be useful for assessing Tc-99m induced biological effects. And mono-nuclear cell cultures seem to be the most appropriate experimental model for the assessment of biological dosimetry of internal irradiation of radionuclides.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.338-342
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• 1994

Pulmonary clearance of Tc-99m-DTPA(PCD) has been used for the measurement of polmonary epithelial permeability. It has been reported to be increased not only in variety of polmonary diseases including ARDS, interstitial fibrosis, and smokers, but also in normal subjects on positive end expiratory pressure respirator, or after exercise. It was also noted that decrease of pulmonary blood flow due to pulmonary arterial obstruction results in delayed PCD. Normal range of PCD varies with institutes. We prospectively measured PCD in 17 normals (5 males and 12 females) consisted of staffs and trainees in the department of radiology of Kangnam St. Mary's hospital using original Bark Nebulizer (India). Age ranged from 32 to 43 years. 370 MBq of Tc-99m-DTPA was inhaled in supine position and supine posterior images were subsequently obtained with 1 min/frame, $64{\times}64$ matrix and word mode for 30min. Regions of interest were set on each lung, whole lungs, and upper, middle and lower thirds of right lung, respectively. Best fit regression curve was obtained by least square method from initial 7min after peak activity on each curve and time for half clearance of maximum activity (t1/2) was calculated. Mean t1/2 was $51{\pm}11.2min$ for whole lung. There was no significant difference between t1/ 2 of right and left lungs. Initial uptake was higher in the lower third and t1/2 was shorter in the lower third than in the upper third(P<0.05). We reviewed several reports on PCD and compared our data with the others. In this study, faster clearance in the lower third may be due to the position imaged with or the environment the subjects belong to, and further investigation is under way.

• The Korean Journal of Nuclear Medicine
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• v.29 no.4
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• pp.518-525
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• 1995

목적 : 안구제거술 후에 삽입한 hydroxyapatite 안구보충물내로 혈관신생이 완전하게 일어 나는 시기를 알아보기 위함이다. 방법 : 안구제거술을 받은 43예의 환자(남자 33예, 여자 10예, 14-56세)에게 대부분 변경되지 않은 방법으로 hydroxyapatite 안구보충물을 삽입한 후 10-23주 사이에 다양한 간격(10-12 주 2예, 13-16주 18예, 17-20주 20예, 21-23주 3예)을 두고 $^{99m}Tc-MDP$ 골주사를 시행하여 보충물내로의 혈관신생 정도를 전향적으로 측정하였다. 정면 및 측면촬영의 정적영상에서 안구보충물의 방사능섭취가 비교(nasal bridge)의 방사능섭취보다 약할 경우를 grade 1, 같을 경을 grade 2, 강할 경우를 grade 3로 나누었으며 grade 2와 3을 혈관신생이 완전하다고 정의하였다. 또한 43예 모두에서 방사능섭취 정도와 관계없이 안구보충물 삽입후 평균 21주되는 시기에 안구보충물에 구멍을 내어 이 구멍으로부터의 출혈여부를 확인한 후 운동성나사(motility peg)를 끼워 의안(prosthesis)과 연결하였다. 43예중 7예에서는 $^{99m}Tc-MDP$ 골주사와 조영제주입후의 자기공명영상(Gd-DTPA T1-weighted images)을 같은 날짜에 시행하여 각각의 예에서 방사능섭취 정도와 조영제증강 정도를 비교하였다. 결과 : 안구보충물내로 완전하게 혈관신생이 일어났던 grade 2와 3의 비율은 안구보충물삽입후 10-12주에서는 0%, 13-16주 33%, 17-20주 50%, 21-23주 67%로써 시간경과에 따라 점차 증가하였다. 골주사소견에 관계없이 안구보충물 삽입후 평균 21주되는 시기에 보충물 앞쪽에 구멍을 내었을 때 43예 모두에서 완전한 혈관신생을 의미하는 출혈을 볼 수 있었다. $^{99m}Tc-MDP$ 골주사와 조영제주입후의 자기공명영상을 둘 다 시행한 7예 각각에서 방사능섭취의 정도와 조영제증강의 정도가 거의 일치하였다. 결론 : 본 예비연구의 결과로써 hydroryapatite 안구보충물 삽입후 21주째에 $^{99m}Tc-MDP$ 골주사를 시행하는 것이 좋을 것으로 생각되며, hydroxyapatite 안구보충물내로의 완전한 혈관신생 여부를 보는 데에는 $^{99m}Tc-MDP$ 골주사가 조영제주입후의 자기공명영상보다 더 경제적이라고 할 수 있겠다.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.59-64
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• 1993

To evaluate the usefulness and differences in diagnosing coronary artery disease (CAD) between men and women of intravenous dipyridamole $^{99m}Tc$-MIBI myocardial SPECT, we obtained $^{99m}Tc$-MIBI myocardial SPECT and compared with the findings of coronary angiographies. Ninety eight male and 37 female patients who underwent dipyridamole $^{99m}Tc$-MIBI myocardial imaging within one month of cardiac catheterization were studied. Scans were considered abnormal if perfusion defect was detected and the defect size was more than 12% for left anterior descending artery (LAD) and circumflex (LCX) and 8% for right coronary artery (RCA) territories. Lesions${\geqq}$50% luminal diameter narrowing were considered significant CAD. Overall sensitivity for detection of CAD was 94.3% in men and 96.4% in women; specificity was 70% in men and 52.6% in women (P=not significant, ns). Vessel-matched sensitivity was 75.3% in men and 72.7% in women (P=ns): specificity was 84.6% in men and 67.9% in women (P < 0.025). For individual coronary artery, the sensitivity in men and women was 87.7%, 81.8% for LAD; 78%, 83.3% for RCA and 52.2%, 46.7% for LCX (P=ns): the specificity was 80%, 40% for LAD (P<0.01), 82.5%, 68.4% for RCA, 88.9%, 86.4% for LCX (P=ns). The hemodynamic parameter after intravenous dipyridamole in men and women were significantly changed; the heart rate was increased and systolic, diastolic blood pressure was decreased. Adverse effects were reported in 58.8% of men and 72.7% in women (P=ns). The incidence of chest pain and headache were higher in women. There was no significant difference in the incidences of nausea, abdominal pain, dizziness, facial flushing, dyspnea. In conclusion, dipyridamole $^{99m}Tc$-MIBI myocardial SPECT is a safe, noninvasive test for evaluation of CAD. There was no gender difference to detect CAD, but more false-positive rate in women especially in the territory of LAD.