• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.271-278
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• 2012

Purpose: Recently implant surgical guides were used for accurate and atraumatic operation. In this study, the accuracy of two different types of surgical guides, positioning device fabricated and stereolithography fabricated surgical guides, were evaluated in four different types of tooth loss models. Materials and methods: Surgical guides were fabricated with stereolithography and positioning device respectively. Implants were placed on 40 models using the two different types of surgical guides. The fitness of the surgical guides was evaluated by measuring the gap between the surgical guide and the model. The accuracy of surgical guide was evaluated on a pre- and post-surgical CT image fusion. Results: The gap between the surgical guide and the model was $1.4{\pm}0.3mm$ and $0.4{\pm}0.3mm$ for the stereolithography and positioning device surgical guide, respectively. The stereolithography showed mesiodistal angular deviation of $3.9{\pm}1.6^{\circ}$, buccolingual angular deviation of $2.7{\pm}1.5^{\circ}$ and vertical deviation of $1.9{\pm}0.9mm$, whereas the positioning device showed mesiodistal angular deviation of $0.7{\pm}0.3^{\circ}$, buccolingual angular deviation of $0.3{\pm}0.2^{\circ}$ and vertical deviation of $0.4{\pm}0.2mm$. The differences were statistically significant between the two groups (P<.05). Conclusion: The laboratory fabricated surgical guides using a positioning device allow implant placement more accurately than the stereolithography surgical guides in dental clinic.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.487-496
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• 2021

Full mouth rehabilitation is re-organizing the occlusion of the remaining teeth and missing teeth considering the functions, esthetics, and neuromuscular harmony. With the loss of multiple teeth, the patient's occlusal plane gradually collapses and the vertical dimension can be reduced. Since reduced vertical dimension can be a potential etiology of the temporomandibular joint and masticatory muscles, prosthetic restoration with increased vertical dimension is required. This case report is about a 68 years old patient with vertical dimension loss due to worn dentition and multiple loss of teeth. In this case, the loss of vertical dimension is assessed carefully using the digital dentistry technology. Using CAD software in digital analysis step, the occlusal plane was established and evaluated using several criteria. Orienting the position of the bone and teeth using CBCT image, patient's condition was visualized in 3 dimension and treatment planning was possible virtually. The information that matches the patient's condylar position with the articulator, which is the virtual face bow, is reproduced on the actual articulator, and evaluated again. After the evaluation, provisional prosthesis was fabricated and it was confirmed that the patient adapts without any abnormality. This was implemented as a final prosthesis. As a result, the patient obtained satisfying results, utilizing the benefits of digital dentistry technology and traditional methods.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.20-24
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• 2019

Purpose Molecular Breast Imaging (MBI) scan is used in nuclear medicine, for which $^{99m}Tc-sestaMIBI$ is administered by intravenous injection. However, the breast uptake rate of $^{99m}Tc-sestaMIBI$ is less than 1% of the total dose administered, relying on blood flow conditions of organs. The purpose of this study is to evaluate the impact of changes to body temperature on the uptake of $^{99m}Tc-sestaMIBI$ in breast tissue. Materials and Methods We investigated 30 breast cancer patients who performed more than one follow-up MBI scan. All scans were acquired by Discovery 750B (Genral Electric Healthcare, USA). $^{99m}Tc-sestaMIBI$ injected with 740 MBq (20 mCi), after 60 minutes, gained bilateral breast CC (CranioCaudal), MLO (Medio Lateral Oblique) View. The follow-up examination was then classified into 15 body temperature control group and 15 body temperature non-control group, and gained breast image in the same way as before. The breast uptake rate was analyzed in the MLO View of the opposite side of the lesion, and blind images were evaluated. Results The breast uptake rate increased by 30.31% in the body temperature control group and it was statistically significant(P<0.05), and 0.96% in the body temperature non-control group, and it was not statistically significant(P=0.955). There was a significant difference in the uptake rate between the body temperature control and the non-control group of P value of 0.01. Evaluation of blind images showed significant results in terms of the quality of the images. Conclusion Increased breast tissue uptake was observed when the subject was kept warm. When the body temperature was raised after injection, dilation of the peripheral blood vessels can be achieved. As a result, the blood flow became smooth and the breast uptake rate increased. In addition, an increase in breast tissue uptake will improve the quality of images.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.1
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• pp.20-26
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• 2023

Fiber content in the storage roots of sweetpotato varies between different varieties. For examples, the high fiber content of certain types has a poor texture when steamed or roasted. This study was conducted to evaluate the optimal sieve mesh size for separating fibers, the chemical composition of fibers and differences in fiber content among different varieties. We found that the separated fiber content (dry weight) of mashed and steamed sweetpotato was higher after washing three times (143.3 mg/100 g) compared with that washed five times (128.4 mg/100 g). The Hogammi variety remained 85.9% of total fiber content at 10 mesh (2,000 ㎛) and 9.6% of total fiber content at 30 mesh (600 ㎛), and Jinyulmi remained 74.9 and 16.7% of total fiber content , respectively. Therefore, a 30 mesh sieve was considered the most suitable for fiber separation. Among the 10 studied cultivars, Jinhongmi showed the lowest amount of fiber (24.8 mg/100 g) and Hogammi had the highest amount (111.4 mg/100 g), which was 4.5 times larger than that of Jinhongmi. Cellulose, hemicellulose and lignin content of separated fibers showed no difference between the viscous-type Hogammi and powdery-type Jinyulmi varieties, with averages of 32.5, 22.3 and 29.6%, respectively. Correlation results using the Image J program showed a significant correlation between the distribution of the stained area and the fiber content (R = 0.74, p < 0.05). Staining distribution differed among varieties, suggesting that a simple fiber content test could be performed using the staining method on raw sweetpotato. These results provide useful information to help inform farmers on the fiber content of different sweetpotato varieties.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.88-93
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• 2011

Purpose: As to analytical method of data, the AutoQUANT software in which it is used quantitative rating of the myocardial perfusion SPECT are reported that there is a difference. Therefore the measured value error of the mutual program is expected to be generated even if the quantitative analysis is made data of the same patient. The purpose of this study is to offer the comparative analysis of myocardial extract method in Quantitative Perfusion SPECT. Materials and methods: We analyzed the 51 patients who were examined by Tc-99m MIBI gated myocardial SPECT in nuclear medicine department of Pusan National University Hospital from June to December 2010(34 men, 17 women, mean age $66.5{\pm}9.9$). We acquired the extracted image in myocardial extract protocol. QPS program that uses the AutoQUANT software measured TID(Transient Ischemic Dilation), ESD(Extent of Stress Defect), SSS(Summed Stress Score). Then analyzed the results. Results: The correlation of appyling myocardial extract is TID(r=0.98), ESD(r=0.99), SSS(r=0.99). In the 95% confidence limit, there was no satistically significant difference(TID p=0.78, ESD p=0.31, SSS p=0.19). After blinding test with a physician for making a qualitative analysis, there was no difference. Conclusion: Quantitative indices in QPS program showed good correlation and the results showed no statistically signigicant difference. The variance between method was small. therefore, the functional parameters by each method can be used interchangeably. Also, we expect patient's satisfaction.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.2
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• pp.137-143
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• 2013

Purpose: We are to find out the difference of calculated dose of treatment planning system (TPS) and measured dose in case of inhomogeneous organ structure. Materials and Methods: Inhomogeneous phantom is made with solid water phantom and cork plate. CT image of inhomogeneous phantom is acquired. Treatment plan is made with TPS (Pinnacle3 9.2. Royal Philips Electronics, Netherlands) and calculated dose of point of interest is acquired. Treatment plan was delivered in the inhomogeneous phantom by ARTISTE (Siemens AG, Germany) measured dose of each point of interest is obtained with Gafchromic EBT2 film (International Specialty Products, US) in the gap between solid water phantom or cork plate. To simulate lung cancer radiation treatment, artificial tumor target of paraffin is inserted in the cork volume of inhomogeneous phantom. Calculated dose and measured dose are acquired as above. Results: In case of inhomogeneous phantom experiment, dose difference of calculated dose and measured dose is about -8.5% at solid water phantom-cork gap and about -7% lower in measured dose at cork-solid water phantom gap. In case of inhomogeneous phantom inserted paraffin target experiment, dose difference is about 5% lower in measured dose at cork-paraffin gap. There is no significant difference at same material gap in both experiments. Conclusion: Radiation dose at the gap between two organs with different electron density is significantly lower than calculated dose with TPS. Therefore, we must be aware of dose calculation error in TPS and great care is suggested in case of radiation treatment planning on inhomogeneous organ structure.

• Investigative Magnetic Resonance Imaging
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• v.6 no.2
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• pp.129-136
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• 2002

Purpose : To evaluate the usefulness of MRCP in the diagnosis of the variable causes of common bile duct(CBD) dilatation, except stone or tumor Materials and methods : Twenty-six patients(M:F=15:11, mean age; 62 years) with both MRCP and ERCP were included in this study. Dynamic MRCP(n=12) and contrast-enhanced MRI(n=10) of abdomen were also added. Dilatation of CBD, intrahepatic ducts and pancreatic duct was evaluated, including coexistence of intrahepatic ductal stone, pancreatic pseudocyst, and papillary or papillary edema. The criteria of CBD dilatation was over than 7mm(n= 21, without cholecystectomy) or 10 mm(n=5, with cholecystecto-my) in diameter on T2-weighted coronal image. Results : The mean diameter of CBD was 12.7mm without cholecystectomy(9-19 mm) and 13.0 mm with cholecystectomy(10-15mm), respectively(p 〉0.05). Cholangitis(n=11, 42.3%), chronic pancreatitis(n=8, 30.8%), stenosis of distal CBD(n= 6, 23.1%), periampullary diverticulum(n=3, 11.5%), stenosis of ampulla of Vater(n=2, 7.7%), dysfunction of sphincter of Oddi(n=2, 7.7%), acute focal pancreatitis in the pancreatic head(n=2, 7.7%), papillitis(n=1, 3.8%), pseudocyst in the pancre atic head(n = 1, 3.8%), and ascaris in CBD(n=1, 3.8%) were noted. Pancreatic duct dilatation(n=10, 38.5%) and duodenal diverticulum(n=3, 11.5%) were also seen on MRC P. On dynamic MRCP(12 patients), distal CBD was visualized in 2 patients(16.7%), which was not shown on routine MRCP. Only 1 patient(10.0%) showed papillitis with slightly enhancing papilla on contrast-enhanced MRI (10 patients). Conclusion : MRCP was thought to be helpful in the evaluation of the causes of CBD dilatation, not caused by stone or tumor, especially in the cases of stenosis of distal CBD and chronic pancreatitis, dysfunction of sphincter of Oddi on dynamic MRCP and cholangitis and pericholangitic abnormality on contrast-enhanced MRI.

• Journal of radiological science and technology
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• v.35 no.4
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• pp.299-308
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• 2012

To perform patient dose surveys in major interventional radiography procedures as a mean of inter-institutional comparison and of establishing reference dose levels with the ultimate goal of optimizing patient doses in the field of interventional radiography. We reviewed international patient dose survey data in the literature and measured patient dose in major interventional radiography procedures (TACE, AVF, PTBD, TFCA, GDC embolization). ESD(Entrance Skin Dose) was measured using TLD chips attached to the patient skin and ED(Effective Dose) was calculated using angiography unit-derived DAP. A survey of patient dose in interventional radiography procedures were also performed with a questionnaire for interventional radiologists and we proposed a guideline for optimizing patient doses in the field of interventional radiology. The patient dose survey data in interventional radiography procedures were very rare in literature compared with those in diagnostic radiography procedures. In TACE, the mean ED was 25.43 mSv and the mean ESD was 511.75 mGy. The mean ED of TACE was not high, but the cumulative dose should be checked, due to longer procedure TACE. In TFCA, the mean ED was 22.6 mSv and it was relatively high compared with data of other countries. In GDC embolization, the mean ED was not available, because GDC embolization was performed with old Image-Intensifier-type unit and there has no unit-installed ionization chamber. Also, the mean ESD of GDC embolization was up to 2,264 mGy and further studies are needed to calculate the net ED of GDC embolization. Patient dose occurred during interventional radiography procedures are high related with the difficulty of the procedure, fluoroscopy time, the number of angiographies and the treatment protocol. Therefore, continuous education and efforts should be made to optimize the patient dose in the field of interventional radiology.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.451-461
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• 2015

In megavoltage (MV) radiotherapy, delivering the dose to the target volume is important while protecting the surrounding normal tissue. The purpose of this study was to evaluate the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) using an edge block in megavoltage X-ray imaging (MVI). We used an edge block, which consists of tungsten with dimensions of 19 (thickness) ${\times}$ 10 (length) ${\times}$ 1 (width) $cm^3$ and measured the pre-sampling MTF at 6 MV energy. Various radiation therapy (RT) devices such as TrueBeam$^{TM}$ (Varian), BEAMVIEW$^{PLUS}$ (Siemens), iViewGT (Elekta) and Clinac$^{(R)}$iX (Varian) were used. As for MTF results, TrueBeam$^{TM}$(Varian) flattening filter free(FFF) showed the highest values of $0.46mm^{-1}$ and $1.40mm^{-1}$ for MTF 0.5 and 0.1. In NPS, iViewGT (Elekta) showed the lowest noise distribution. In DQE, iViewGT (Elekta) showed the best efficiency at a peak DQE and $1mm^{-1}DQE$ of 0.0026 and 0.00014, respectively. This study could be used not only for traditional QA imaging but also for quantitative MTF, NPS, and DQE measurement for development of an electronic portal imaging device (EPID).

• The Journal of Korean Society for Radiation Therapy
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• v.21 no.1
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• pp.25-31
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• 2009

Purpose: Evaluate the mold we have made to improve the reproducibility of the patient position and make homogeneous dose distribution to the treatment volume effectively when treating the patient who has hypervascular ulcer on her tongue caused by paraneoplastic autoimmune multiorgan syndrome by mold brachytherapy. Materials and Methods: The mold is consisted of upper and lower parts. We inserted 2 mm of lead sheet on the gums toward the oral cavity to protect them from unnecessary irradiation during the treatment. We had planned on orthogonal images obtained the patient. 200 cGy was delivered in every fraction with a total dose of 3000 cGy. To evaluate the effect of the lead sheet, we made a measurement with a phantom that has gums and tongue made of tissue with an equivalent material (bolus). Five of TLDs were placed on the interesting points of gums to measure the dose during irradiation with lead sheet and without lead sheet for three times respectively. Results: The result of the measurement without lead sheet are A: 33.9 cGy, B: 30.1 cGy, C: 31.8 cGy, D: 23.3 cGy, E: 24.1 cGy. The results of measurement with lead sheet are A: 20.6 cGy, B: 18.8 cGy, C: 19.6 cGy, D: 14.7 cGy, E: 15.1 cGy. Conclusion: Since we are using the mold made in our department during the treatment of the patient with hypervascular ulcer on tongue, we could deliver a proper dose to the treatment volume. In addition, the mold provided highly accurate and reproducible treatment and reduced the dose to the gums and teeth. Therefore, the possibility of side effects could be decreased significantly.