1.Improved Activity Estimation using Combined Scatter and Attenuation Correction in SPECT.
Jeong Rim LEE ; Chang Woon CHOI ; Sang Moo LIM ; Seong Wun HONG
Korean Journal of Nuclear Medicine 1998;32(4):382-390
PURPOSE: The pvrpose of this study was to evaluate the accuracy of radioactivity quantitation in Tc-99m SPECT by using combined scatter and attenuation correction. MATERIALS AND METHODS: A cylindrical phantom which simulates tumors (T) and normal tissue (B) was filled with varying activity ratios of Tc-99m. We acquired emission scans of the phantom using a three-headed SPECT system (Trionix, Inc.) witb two energy windows (photopeak window: 126 154 keV and scatter window: 101 123 keV). We performed the scatter correction with dual-energy window subtraction method (k=0.4) and Chang attenuation correction. Three sets of SPECT images were reconstructed using combined scatter and attenuation correction (SC+AC', attenuation correction (AC) and without any correction (NONE). We compared T/B ratio, irnage contrast [(T-B)/(T+B)) and absolute radioactivity with true values. RESULTS: SC+AC images had the highest mean values of T/B ratios. Image contrast was 0.92 in SC+AC, which was close to the true value of 1, and higher than AC (0.77) or NONE (0.80). Errors of true activity by SPECT images ranged from 1 to 11% for SC+AC, 22-47% for AC, and 2 16% for NONE in a phantom which was located 2.4cm from the phantom surface. In a phantom located 10,0cm from the surface, SC+AC underestimated by ?4%, NON.E 40%. However, AC overestimated by 10%. CONCLUSION: We conclude that accurate SPECT activity quantitation of Tc-99m distribution can be achieved by dual window scatter correc.tion combined with attenuation correction.
Radioactivity
;
Tomography, Emission-Computed, Single-Photon*
2.Membranes for the Guided Bone Regeneration.
Maxillofacial Plastic and Reconstructive Surgery 2014;36(6):239-246
Many kinds of membrane have been used for the guided bone regeneration (GBR) technique. However, most membranes do not fulfill all requirements for the ideal membrane for the GBR technique. Among them, collagen membrane has been most widely used. However, its high price and weak tensile strength in wet condition are limitations for wide clinical application. Synthetic polymers have also been used for the GBR technique. Recently, silk based membrane has been considered as a membrane for the GBR technique. Despite many promising preclinical data for use of a silk membrane, clinical data regarding the silk membrane has been limited. However, silk based material has been used clinically as vessel-tie material and an electrospun silk membrane was applied successfully to patients. No adverse effect related to the silk suture has been reported. Considering that silk membrane can be provided to patients at a cheap price, its clinical application should be encouraged.
Bone Regeneration*
;
Collagen
;
Humans
;
Membranes*
;
Polymers
;
Silk
;
Sutures
;
Tensile Strength
3.Surface ECG Findings of the Patients with Left Isomerism.
Jae Kon KO ; Seong Ho KIM ; Jong Woon CHOI ; Dug Ha KIM ; Heung Jae LEE
Korean Circulation Journal 1991;21(6):1237-1241
Surface ECG findings in 29 patients with left isomerism were reviewed. Among the total 46 wave axis distributions, 25(54%) were abnormal axis, not originated from sinus node. Congenital atrioventricular block was found in 2 children. 6 patients showed the bradycardia and junctional escape rhythm intermittently or persistently. 4 of them, not related with heart surgery, were much older than 2 patients who showed these ECG findings after heart surgery. These ECG findings suggested the possibility of occurrence of sinus node or subsidiary pacemaker dysfunction in the patients with left isomerism, especially in the older patients. So we thought that electrophysiologic evaluation is necessary in some patients with left isomerism.
Atrioventricular Block
;
Axis, Cervical Vertebra
;
Bradycardia
;
Child
;
Electrocardiography*
;
Humans
;
Isomerism*
;
Sinoatrial Node
;
Thoracic Surgery
;
United Nations
4.A Case of Zosteriform Cutaneous Metastasis.
Seong Hoon KIM ; Woon Ho KIM ; Kwang Joong KIM ; Eil Soo LEE
Korean Journal of Dermatology 1990;28(6):814-817
We report a case of zosteriform cutaneous metastasis from lung cancer in a 72- year-old male patient who have asymptomatic confluent or discrete hard papulonodules over the right upper arm and right side of chest. Histopathologic examinations of the cutaneous lesion revealed neoplastic cell, which showing glandular structure, infiltrating in the drmis and subcutaneous layer. Also histopathologic findings of metastatic lesion of skull and olecranon are similar to them. Fie died after three months from the appearance of cutaneous metastasis
Arm
;
Humans
;
Lung Neoplasms
;
Male
;
Neoplasm Metastasis*
;
Olecranon Process
;
Skull
;
Thorax
5.Invasive aspergillosis of the maxillary antrum and lung in a patient with diabetes mellitus and liver cirrhosis
Ill Kyu KIM ; Seong Jun LEE ; Soo Yong HA ; Young Chae CHU ; Yong Woon SHIN
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 1991;13(4):456-461
No abstract available.
Aspergillosis
;
Diabetes Mellitus
;
Humans
;
Liver Cirrhosis
;
Liver
;
Lung
;
Maxillary Sinus
6.A case of asynchromous bilateral nonfunctioning adrenal cortical carcinoma.
Chun Soo PARK ; Seong Woon PARK ; Yoon Seong LEE ; Kil Hyun OH
Korean Journal of Urology 1993;34(4):720-723
Bilateral nonfunctioning adrenal cortical carcinoma is an extremely rare disease with poor prognosis. We report a case of asynchronous bilateral nonfunctioning adrenal cotical carcinoma. The patient was a 55 year-old man who had complained of discomfort in the right upper quadrant and flank area. There was no endocrinological abnomaliries. Abdominal CT revealed about 9.5 x 7.0 cm sized right adrenal mass. Under the impression of nonfunctioning adrenal cortical carcinorna, right radical adrenalectomy was performed. After 1 year from operation, 5.0 x 7.0 x 6.0 cm sized new mass was detected in the left adrenal gland with metastasis to the peritoneum.
Adrenal Glands
;
Adrenalectomy
;
Adrenocortical Carcinoma*
;
Humans
;
Middle Aged
;
Neoplasm Metastasis
;
Peritoneum
;
Prognosis
;
Rare Diseases
;
Tomography, X-Ray Computed
7.The Usefulness of F-18-FDG PET and The Effect of Scan Protocol in Diagnosis of Intraocular Tumors.
Seong Woon HONG ; Chang Woon CHOI ; Sang Moo LIM ; Tae Won LEE ; Jae Sung LEE ; Weon Il YANG ; Byeung Il KIM ; Min Kyeung SIM
Korean Journal of Nuclear Medicine 1999;33(5):439-451
PURPOSE: It is important to differentiate malignant from benign lesions of intraocular masses in choosing therapeutic plan. Biopsy of intraocular tumor is not recommended due to the risk of visual damage. We evaluated the usefulness of F-18-FDG PET imaging in diagnosing intraocular neoplasms. MATERIALS AND METHODS: F-l8-FDG PET scan was performed in 13 patients (15 lesions) suspected to have malignant intraocular tumors. There were 3 benign lesions (retinal detachment, choroidal effusion and hemorrhage) and 10 patients with 12 malignant lesions (3 melanomas, 7 retinoblastomas and 2 metastatic cancers). Regional eye images (256*256 and 128*128 matrices) were obtained with or without attenuation correction. Whole body scan was also performed in eight patients (3 benign and 6 malignant lesions). RESULTS: All malignant lesions were visualized while all benign lesions were not visualized. The mean peak standardized uptake value (SUV) of malignant lesions was 2.64+/-0.57 g/ml. There was no correlations between peak SUV and tumor volume. Two large malignant lesions (>1000 mm3 ) showed hot uptake on whole body scan. But two medium-sized lesions (100-l000 mm3) looked faint and two small (<100 mm3) lesions were not visualized. The images reconstructed with 256*256 matrix showed lesions more clearly than those with 128X128 matrix. CONCLUSION: F-18-FDG PET scan is highly sensitivity in detecting malignant intraocular tumor. For the evaluation of small-sized intraocular lesions, whole body scan is not appropriate because of low sensitivity. A regional scan with sufficient acquisition time is recommended for that purpose. Image reconstruction in matrix size of 256*256 produced clearer images than the ones in 128X128, but it does not affect the diagnostic sensitivity.
Biopsy
;
Choroid
;
Diagnosis*
;
Humans
;
Image Processing, Computer-Assisted
;
Melanoma
;
Orbital Neoplasms
;
Positron-Emission Tomography
;
Retinoblastoma
;
Tumor Burden
;
Whole Body Imaging
8.Factors Affecting Primary Stability on Sites of Alveolar Ridge Preservation Using Porcine-derived Bone Minerals
Su-Yeon LEE ; Young LEE ; Seong-Ho CHOI ; Dong-Woon LEE
Journal of Korean Dental Science 2021;14(1):1-11
Purpose:
The alveolar ridge preservation (ARP) is widely conducted for implant placement. However, experimental results using deproteinized porcine bone mineral (DPBM) have been scarce. This retrospective study evaluated factors affecting the primary stability of implants in an area where ARP was performed using DPBM.
Materials and Methods:
Thirty-eight patients were divided into two groups based on the primary stability, with torque value of 30 Ncm as borderline. To determine the factors that affect the primary stability of implants, we collected data from patients’ medical records including age, sex, reentry time, socket location, remaining bone wall at the time of extraction, and type of collagen membrane, as well as from radiographs and histomorphometric analysis.Result: The results showed statistically significant difference for the remaining extraction socket wall (P=0.014), residual graft (P=0.029), and fibrovascular tissue (P=0.02) between the two groups. There was an insignificant tendency toward the time of reentry surgery (P=0.052) and location (P=0.077). All implants placed in sites using DPBM functioned well up to 3 years.
Conclusion
Within the limitations of the present study, extraction socket wall, residual graft, and fibrovascular tissue can affect the primary stability at the time of implant placement on grafted sites using DPBM and collagen membranes. In addition, reentry time and locations can be considered. In future studies, comparative experiments in quantified models will be required to supporting the findings.
9.A Study on the Urinary Iodine Excretion in Normal subjects and Patients with Thyroid disease
Seong Yeon KIM ; Bo Youn CHO ; Hong Kyu LEE ; Seok In LEE ; Woon Bae KIM ; Hye Young PARK ; Chang Soon KOH
Journal of Korean Society of Endocrinology 1995;10(4):386-394
An adequate supply of dietary iodine is essential for the synthesis of the thyroid hormons. The measurement of dietary iodine intake is important for the clinical assessment of thyroid disease, especially in areas where iodine intake is excessive or deficient.To evaluate dietary iodine intake in Korean and its effects on thyroid function, we measured urinary iodine excretion with morning urine by electrode method in 184 normal subjects, 96 postpartum women and 181 patients with thyroid disease from October 1994 to February 1995. The results were as follows;1) In normal control, the mean value of urinary iodine excretion was 3.8+-2.7mg/L (range 0.1-15.0mg/L). However, there was no sex and age differences in the urinary iodine excretion.2) In postpartum women, the urinary iodine excretion was 9.0+-10.8mg/L who were not taken high iodine diet(Miyok-Guk), the mean value was statistically higher than normal control(p<0.01) and significant increased the urinary iodine excretion after eating of high iodine diet(p<0.01).3) In volunteer, there were increase of urinary iodine excretion more than 10 folds after high iodine diet and medication.4) The urinary iodine excretion in patients with thyroid diseases was not different from normal control, and there were no significant differences of urinary iodine excretion among the patient groups. The urinary iodine excretion in the acute stage of patients with subactue thyroiditis or painless thyroiditis was significantly increased compared to the recovery stage. However, it was not significantly different from that of normal control.In conclusion, urinary iodine excretion in Korean population is very high comparing to the reported data in Western population but similar with Japanese. The urinary iodine excretion is significant increase( more than 10-folds of basal level) after high iodine diet or high iodine containing medication in postpartum women or healthy persons. As a clue of destruction induced thyrotoxicosis, the urinary iodine excretion measurement is not valid in area where iodine intake is excessive like Korea.
Asian Continental Ancestry Group
;
Diet
;
Eating
;
Electrodes
;
Humans
;
Iodine
;
Korea
;
Methods
;
Postpartum Period
;
Thyroid Diseases
;
Thyroid Gland
;
Thyroiditis
;
Thyrotoxicosis
;
Volunteers
10.Partial remission with transarterial embolization in a case of metastatic adrenal cortical carcinoma.
Moon Soo KOH ; Myung Shik LEE ; Seong Woon HONG ; Duk LIM
Journal of Korean Medical Science 1991;6(2):173-176
A case of metastatic adrenal cortical carcinoma in which partial remission was achieved with transarterial embolization is presented as probably the first reported case in the literature to date. A 29-year-old woman was admitted because of adrenal cortical carcinoma which had not responded to mitotane. A left adrenalectomy with segmentectomy of the involved liver had been done previously. Abdominal computerized tomography demonstrated multiple large metastatic tumors in the liver. Transarterial embolization with Gelfoam and 20 mCi of 131I-labeled lipiodol was performed and resulted in a decrease in tumor size and biochemical parameters. Transarterial embolization can be one of the therapeutic modalities for metastatic adrenal cortical carcinomas.
Adrenal Cortex Neoplasms/metabolism/*therapy
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Adult
;
*Embolization, Therapeutic
;
Female
;
Gelatin Sponge, Absorbable
;
Hepatic Artery
;
Humans
;
Hydrocortisone/metabolism
;
Iodine Radioisotopes
;
Iodized Oil
;
Liver Neoplasms/metabolism/*secondary/*therapy