• The Journal of the Korea Contents Association
• /
• v.14 no.12
• /
• pp.845-853
• /
• 2014

In this study, we measured the dose reaching the OSLD dosimeter by using the regular lead apron, and air gap apron through 3 experiments, and researched the reductive effect of air gap apron on exposure dose based on the 140 keV gamma ray radiating from $^{99m}technetium$, which is the most commonly used in nuclear medicine. As a result, when the gap between the dosimeter and 0.2mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.515 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.138 mSv, which shows reductive effect of dose as much as 0.388 mSv. When the gap between the dosimeter and 0.5mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.296 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.075 mSv, which shows reductive effect of dose as much as 0.221 mSv. As we check the cumulative dosage for 3 days, the lead apron without air layer shows average 0.239 mSv, and the air gap apron shows 0.176 mSv, which is actually reduced by 0.062 mSv. As we check the cumulative dosage for a month, the lead apron without air layer shows 0.59 mSv, and the air gap apron shows 0.54 mSv, which is reduced by 0.05 mSv.

• Analytical Science and Technology
• /
• v.25 no.3
• /
• pp.178-189
• /
• 2012

As phthalates classified as toxic to reproduction category 2 and endocrine disrupting chemicals were more strictly regulated as Substances of Very High Concern (SVHC) for authorization in under EU REACH and considered as priority substances in RoHS II, standardization of phthalate testing method is now being proposed in IEC 62321 of IEC TC 111 and the 2nd revision of KS M 1991 is also finished. In order to assist standardization activities related to phthalating testing, solvent extraction part of existing national standards were compared and verified. Recovery of DEHP (diethylhexyl phthalate) from PVC (polyvinyl chloride) by Soxhlet extraction increased in the order of methanol, toluene, dichloromethane and hexane from 46.9% to 95.3% as measured by GC-MS. Optimum extraction time was verified to be 6 hours using hexane. Recovery of DBP (dibutyl phthalate), BBP (butylbenzyl phthalate), and DEHP from different matrixes such as PVC, nitro cellulose, ABS (acrylonitrile butadiene styrene). and EPDM(ethylene propylene diene monomer) rubber were evaluated to be more than 90% up to 99%. The detection limits of phthalates in solvent extraction followed by GC-MS analysis were 0.08~0.3 ${\mu}g/mL$ in solution and 8~30 mg/Kg in polymeric samples. GC-MS analyses of phthalates were carried out using different solvent extraction based on the EN 14372, ASTM D 7083, Japanese test method (MHLW 0906-4) and KS M 1991, proving that equivalent recoveries ranging from 98%~99% were obtained. DBP and DEHP were detected in three consumer products such as a child toy, a power cable and manicure with the amount of 22~1,910 mg/kg.

• Journal of the Korean Society of Radiology
• /
• v.13 no.2
• /
• pp.271-281
• /
• 2019

This study investigated the shielding efficiency of various types of shielding materials and measured the dose by organ using the phantom. Results of Shielding Efficiency Measurement Using Personal Radiation Meter. Among the various shielding materials, 1.1 mm RNS-TX composed of nano tungsten showed the highest shielding efficiency and 0.2 mm lead shielding showed the lowest shielding efficiency. 99mTc 30 mCi was exposed to the phantom for 120 minutes and the result of the measurement of the organs. 20.53 mSv without radiation protective clothing, 8.75 mSv when wearing 0.25 mm Pb protective clothing, 6.03 mSv when wearing 0.5 mm Pb protective clothing. 131I 2 mCi mCi was exposed to the phantom for 120 minutes and the result of the measurement of the organs. 7.71 mSv without radiation protective clothing, 4.88 mSv when wearing 0.25 mm Pb protective clothing, 2.79 mSv when wearing 0.5 mm Pb protective clothing. 18F 5 mCi was exposed to the phantom for 120 minutes and the result of the measurement of the organs. 16.39 mSv without radiation protective clothing, 15.84 mSv when wearing 0.25 mm Pb protective clothing, 12.52 mSv when wearing 0.5 mm Pb protective clothing. None of the radiation workers working in the nuclear medicine department exceeded the dose limit. However, when compared with other workers in the hospital, they showed a relatively high dose. Therefore, it is necessary to prepare measures to reduce and manage the dose of radiation workers in the nuclear medicine department through the wearing of radiation protective clothing made of lightweight, shielding material with good shielding efficiency, circulation task, task sharing, and substitution equipment such as auto dispenser.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.19 no.2
• /
• pp.81-86
• /
• 2015

Purpose This study was to evaluate the usefulness through the comparison of patients group and healthy control group by acquiring a variety of functional parameters index from time-activity curves of salivary gland scintigraphy using $^{99m}Tc$. Materials and Methods From December 2014 to February 2015 with the targets of 30 patients in the patient group who presented themselves with xerostomia and underwent the salivary gland scan and 10 people in healthy control group, approximately 30 minutes of dynamic Scan was carried out after the intravenous bolus injection of 370 MBq of $^{99m}TcO_4{^-}$ and per os stimulation with Vitamin C powder 20 minutes after the injection. The method of quantitative analysis was as follows, the time-activity curve was drawn after the parotid gland and submandible gland were prescribed as a region of interest, a variety of functional parameters index was obtained in each position of the curve, and the patients group and the control group were compared. Results As for the methods applied in comparison and measurement, uptake ratio (UR), time at maximum counts (Tmax), time at minimum counts (Tmin), maximum accumulation (MA), accumulation velocity, maximum secretion (MS), maximum stimulation secretion (MSS), and secretion velocity (SV) were used. In the comparison of functional parameters index of patient group and normal group, the healthy normal group showed significant difference compared to the patient group in all indices except for the minimum radioactivity time (Tmin), and also in terms of variation over time the normal group showed significant difference compared to the patient group (p<0.05). Conclusion Consequently, it was considered that the quantitative analysis that used a variety of functional parameters index would be useful for evaluating the function of the salivary glands of the patients with xerostomia as an objective and standardized information.

• Childhood Kidney Diseases
• /
• v.3 no.2
• /
• pp.117-122
• /
• 1999

Purpose : We studied the correlation between urinalysis and radiologic findings in infants and children with urinary tract infection. Method : Urine Dipstick test and unstained urine microscopic examination were carried out in 56 infants and children who were hospitallized with the diagnosis of urinary infection by pocitive urine culture at Seoul Adventist from September 1996 through August 1998. Urine was collected by midsream, catheter, urine bag after cleansing or bladder puncture. Renal sonography and $^{99m}Tc-DMSA$ renal scan or voiding cystoureterography were studied. Results : 1)In dipstick analysis, leukocyte esterase(LE) were positive in 30 cases of 56 patients(54%) and Nitrite were positive in 20 cases of 56 patients(36%) and LE or Nitrite were positive in 38 cases of 56 children with UTI(68%). 2)In microscopic analysis, WBC were positive in 38 cases of patients(68%) and bacteria were positive in 23 cases of 56 patients(41%) and WBC or bacteria were positive in 41 cases of 56 children with UTI(71%). 3)Ten cases of 56 UTI patients(18%) showed negative finding in Dipstick and microscopic analysis. 4)There was no significant difference in positive rate of dipstick(71% vs 66%) and microscopia analysis(83% vs 66%) between two group with or without renal scar on $^{99m}Tc-DMSA$ scan (P=0.117). 5)There was no significnt difference in positive rate of dipstick(100% vs 91%) and microscopic analysis(100% vs 100%) between two groups with or without vesicoureteral reflux on VCUG. Conclusion : There was no specific relationships between the abnormal urinalysis and the abnormal findings on $^{99m}Tc-DMSA$ scan or VCUG.

• The Korean Journal of Nuclear Medicine
• /
• v.37 no.6
• /
• pp.428-436
• /
• 2003

Purpose: Increased periarticular uptake could be associated with peripheral bone marrow expansion in cancer patients with axial bone marrow metastasis. We compared bone scan and bone marrow scan to investigate whether the increased whole body count in patients with increased periarticular uptake on bone scan is useful in the diagnosis of axial marrow metastasis, and evaluate the role of additional bone marrow scan in these cases. Materials and methods: Twelve patients with malignant diseases who showed increased periarticular uptake on bone scan were included. Whole body count was measured on bone scan and it is considered to be increased when the count is more than twice of other patients. Bone marrow scan was taken within 3-7 days. Results: Five hematologic malignancy, 3 stomach cancer, 2 breast cancer, 1 prostate cancer and 1 lung cacner were included. All three patients with increased whole body count on bone scan showed axial marrow suppression and peripheral marrow expansion. Eight of 9 patients without increased whole body count showed axial marrow suppression and peripheral marrow expansion. One turned out to be blastic crisis of chronic myelogeneous leukemia, and seven showed normal axial marrow with peripheral marrow expansion in chronic anemia of malignancy. The last one without increased whole body count showed normal bone marrow scan finding. Conclusion: Increased whole body count on bone scan could be a clue to axial bone marrow metastasis in cancer patients with increased periarticular uptake, and bone marrow scan is a valuable method for differential diagnosis in these cases.

• The Korean Journal of Nuclear Medicine
• /
• v.36 no.5
• /
• pp.298-305
• /
• 2002

Purpose: Bone marrow scintigraphy has been used to evaluate the status of bone marrow in various hematologic disorders. We have analyzed the peripheral distribution pattern and central uptake ratio of bone marrow using anti-NCA-95 monoclonal antibody and the their correlation in patients with various hematologic malignancy. Materials and Methods: Bone marrow immunoscintigraphy was performed using Tc-99m anti-granulocyte monoclonal mouse antibody BW 250/183. Fifty patients were classified into four groups; 11 with acute myelogenous leukemia, 12 with acute lymphocytic leukemia, 15 with lymphoma and 12 with myelodysplastic syndrome. The extension of peripheral bone marrow was categorized into four grades: I, II, III and IV. The activity of central bene marrow was expressed as sacroiliac uptake ratio. Results: The patient's number was 4 in grade I, 27 in grade II, 15 in grade III and 4 in grade IV according to extension of peripheral bone marrow. The extension of peripheral bone marrow was marked (58% in grade III and IV) in myelodysplastic syndrome and acute lymphocytic leukemia and mild (93% in grade I and II) in lymphoma. Sacroiliac uptake ratio was highest ($8.5{\pm}4.0$) in myelodysplastic syndrome and lowest ($5.9{\pm}3.6$) in acute myelogenous leukemia, but not significantly different among four patient groups (p>0.05). Sacroiliac uptake ratio of whole patients was significantly different among four grades (p=0.003), but there was not correlated between grade of peripheral bone marrow and sacroiliac uptake ratio (r=0.05). Conclusion: The pattern of peripheral bone marrow extension and activity of central hemopoietic marrow were not specific to the disease entities. Response of hemopoietic bone marrow may be evaluated on both peripheral and central bone marrow in patients with hematologic malignancy.

• Clinical and Experimental Pediatrics
• /
• v.49 no.1
• /
• pp.87-92
• /
• 2006

Purpose : It is difficult to make a distinction between lower urinary tract infection(UTI) and acute pyelonephritis(APN) during the acute phase of febrile UTI due to nonspecific clinical symptoms and laboratory findings, especially among young children. We measured the serum procalcitonin(PCT) in children with UTI to distinguish between acute pyelonephritis and lower UTI, and to determine the accuracy of PCT measurement compared with other inflammatory markers. Methods : Serum samples were taken from children who admitted with unexplained fever or were suspected of having UTI. 51 children(mean $12.2{\pm}11.4$ months) were enrolled in this study. Leukocyte counts, erythrocyte sedimentation rates(ESR) and C-reactive protein(CRP) were also measured. Renal parenchymal involvement was assessed by $^{99m}Tc$ DMSA scintigraphy in the first 7 days after admission. PCT was measured by immunoluminometric assay. Results : PCT values were significantly correlated with the presence of renal defects in children with UTI(n=16)($5.06{\pm}12.97{\mu}g/L$, P<0.05). However, PCT values were not significantly different between children with UTI without renal damage(n=18) and children without UTI(n=17). Using a cutoff of $0.5{\mu}g/L$ for PCT and 20 mm/hr for ESR, 20 mg/L for CRP, sensitivity and specificity in distinguishing between UTI with and without renal involvement were 81.3 percent and 88.9 percent for PCT 87.5 percent and 72.2 percent for ESR, and 87.5 percent and 55.6 percent for CRP, respectively. Positive and negative predictive values were 86.7 percent and 84.2 percent for PCT and 60.9 percent and 81.8 percent for CRP, respectively. Conclusion : In febrile UTI, PCT values were more specific than CRP, ESR and leukocyte count for the identification of patients who might develop renal defects.

• Journal of radiological science and technology
• /
• v.27 no.3
• /
• pp.31-41
• /
• 2004

Attention deficit hyperactivity disorder(ADHD)is one of the most common psychiatric disorders in childhood, especially school age children and persisting into adult. ADHD is affected 7.6% in our children, Korea. and persisting into $15{\sim}20%$ in adult. And it is characterized by hyperactivity, inattention and impulsivity. Brain imaging is one of way to diagnosis for ADHD. Brain imaging studies may be provide information two types - structural and functional imaging. Structural and functional images of the brain play an important role in management of neurologic and psyciatric disorders. Brain SPECT, with perfusion imaging radiopharmaceuticals is one of the appropriate test to diagnosis of neurologic and psychiatric diseases. Ther are a few studies about separated analysis between boys and girls ADHD SPECT brain images. Selection of Probability level(P-value) is very important to determind the abnormalities when analysis a data by SPM. SPM is a statistical method used for image analysis and determine statistical different between two groups-normal and ADHD. Commonly used P-value is P<0.05 in statistical analysis. The purpose of this study is to evaluation of blood flow clusters distribution, between boys and girls ADHD. The number of normal boys are 8(6-7y, average : $9.6{\pm}3.9y$) and 51(4-11y, average : $9.0{\pm}2.4$) ADHD patients, and normal girls are 4(6-12y, average : $9{\pm}2.4y$) and 13(2-13y, average $10{\pm}3.5y$) ADHD patiens. Blood flow tracer $^{99m}Tc-ethylcysteinate$ dimer(ECD) injected as rCBF agent and take blood flow images after 30 min. during sleeping by SPECT camera. The anatomical region of hyperperfusion of rCBF in boys ADHD group is posterior cingulate gyrus and hyperperfusion rate is 15.39-15.77% according to p-value. And girls ADHD group appears at posterior cerebellum, Lt. cerbral limbic lobe and Lt. Rt. cerebral temporal lobe. These areas hyperperfusion rate are 24.68-31.25%. Hypoperfusion areas in boys ADHD,s brain are Lt. cerebral insular gyrus, Lt. Rt. frontal lobe and mid-prefrontal lobe, these areas decresed blood flow as 15.21-15.64%. Girls ADHD decreased blood flow regions are Lt. cerebral insular gyrus, Lt. cerebral frontal and temporal lobe, Lt. Rt. lentiform nucleus and Lt. parietal lobe. And hypoperfusion rate is 30.57-30.85% in girls ADHD. The girls ADHD group's perfusion rate is more variable than boys. The studies about rCBF in ADHD, should be separate with boys and girls.

• The Korean Journal of Nuclear Medicine
• /
• v.25 no.1
• /
• pp.6-16
• /
• 1991

Regional cerebral blood flow (rCBF) was evaluated in 12 children ranging in age from 2.7 to 10.0 yr using $^{99m}Tc-HMPAO$ SPECT. For quantitative analysis, 13 pairs of homologous regions of interest (ROIs) were created on three attenuation-corrected 18.8 mm thick transverse slices matching the cerebral cortical regions, deep gray matter, cerebellar hemisphere, and vascular territories, and the semiquantitative indices including "right to left ratio" [(mean count/voxel of homologous right ROI) / (mean count/voxel of homologous left ROI)] and "regional index"(RI) [(mean count/voxel of a ROI)/ (mean count/voxel of all ROIs of each hemisphere)] were calculated. Mean values of right to left ratios of homologous regions ranged from 0.984 to 1.028 in children under 5 yr (group 1) and from 0.982 to 1.012 in children between 5 and 10 yr (group 2), and the mean $value{\pm}2S.D.$ for each region did not exceed 11% and 12% in group 1 and group 2, respectively. There were no statistically significant differences between the RIs of the homologous right and left regions. Significant differences of RIs were found both between vascular regions (p<0.0005 for goup 1, and p=0.0001 for goup 2) and between regions of cerebral cortices (p<0.0005 for group 1, and p<0.005 for group 2) with a relatively high value in the occipital cortex and the lower values in the cerebellum and deep gray matter among the regions of cerebral cortices in both groups. There were no significant differences between the RIs of corresponding regions of group 1 and group 2, except a significantly higher value of right deep gray matter in group 2 than in group 1(p=0.0301). The RIs of the superior frontal cortex and deep gray matter showed to be positively correlated with age (superior frontal cortex; right: rs=0.5254, p=0.0814, left : rs=0.5919, p=0.0496/deep gray matter; right: rs=0.8246, p=0.0062, left: rs=0.6266, p=0.0377). The results suggest that the rCBF pattern of children approaches that of adults in an accipito-rostral direction. This time course of rCBF changes is in agreement with behavioral, neurophysiological, and anatomical alterations known to occur in the developing brain.