• Journal of the Korean Society of Radiology
• /
• v.83 no.2
• /
• pp.331-343
• /
• 2022

Purpose To systematically compare the performance of liver imaging reporting and data system treatment response (LR-TR) with the modified Response Evaluation Criteria in Solid Tumors (mRECIST) for diagnosing viable hepatocellular carcinoma (HCC) treated with locoregional therapy (LRT). Materials and Methods Original studies of intra-individual comparisons between the diagnostic performance of LR-TR and mRECIST using dynamic contrast-enhanced CT or MRI were searched in MEDLINE and EMBASE, up to August 25, 2021. The reference standard for tumor viability was surgical pathology. The meta-analytic pooled sensitivity and specificity of the viable category using each criterion were calculated using a bivariate random-effects model and compared using bivariate meta-regression. Results For five eligible studies (430 patients with 631 treated observations), the pooled per-lesion sensitivities and specificities were 58% (95% confidence interval [CI], 45%-70%) and 93% (95% CI, 88%-96%) for the LR-TR viable category and 56% (95% CI, 42%-69%) and 86% (95% CI, 72%-94%) for the mRECIST viable category, respectively. The LR-TR viable category provided significantly higher pooled specificity (p < 0.01) than the mRECIST but comparable pooled sensitivity (p = 0.53). Conclusion The LR-TR algorithm demonstrated better specificity than mRECIST, without a significant difference in sensitivity for the diagnosis of pathologically viable HCC after LRT.

• Journal of the Korean Society of Radiology
• /
• v.81 no.4
• /
• pp.899-911
• /
• 2020

Purpose To evaluate the safety and efficacy of the newly designed open-cell type self-expandable nitinol stent (NiTi-stent) for peripheral arteries. Materials and Methods Twenty-eight limbs of 14 minipigs were randomly assigned to the NiTistent group or conventional nitinol stent group. Stents were symmetrically implanted into the iliac arteries of each animal using carotid artery approach and were observed for 1 month (n = 5) and 6 months (n = 9). The angiographic lumen diameter (ALD), late lumen loss, angiographic stenosis, histomorphometric lumen area, neointimal area, and area stenosis were analyzed and compared between the groups. Results Stent migration, stent fracture, or thrombus formation were not observed in either group. At the 1-month follow-up, the neointimal area (p = 0.008) and area stenosis (p = 0.016) were significantly smaller in the NiTi-stent group than in the control group. At the 6-months followup, the NiTi-stent group showed significantly larger ALD (p = 0.014), less late lumen loss (p = 0.019), less angiographic stenosis (p = 0.014), larger lumen area (p = 0.040), and smaller neointimal area and area stenosis (p = 0.004 and p = 0.014, respectively) compared with the control group. Conclusion The NiTi-stent is as safe and effective as the conventional nitinol stent and induces less neointimal hyperplasia in a minipig iliac artery model.

• Journal of the Korean Society of Radiology
• /
• v.82 no.3
• /
• pp.654-669
• /
• 2021

Purpose To evaluate the accuracy of MRI in predicting the pathological complete response (pCR) and the residual tumor size of breast cancer after neoadjucant chemotherapy (NAC), and to determine the factors affecting the accuarcy. Materials and Methods Eighty-eight breast cancer patients who underwent surgery after NAC at our center between 2010 and 2017 were included in this study. pCR was defined as the absence of invasive cancer on pathological evaluation. The maximum diameter of the residual tumor on post-NAC MRI was compared with the tumor size of the surgical specimen measured pathologically. Statistical analysis was performed to elucidate the factors affecting pCR and the residual tumor size-discrepancy between the MRI and the pathological measurements. Results The pCR rate was 10%. The diagnostic accuracy of MRI and the area under the curve for predicting pCR were 90.91% and 0.8017, respectively. The residual tumor sizes obtained using MRI and pathological measurements showed a strong correlation (r = 0.9, p < 0.001), especially in patients with a single mass lesion (p = 0.047). The size discrepancy between MRI and the pathological measurements was significantly greater in patients with the luminal type (p = 0.023) and multifocal tumors/non-mass enhancement on pre-NAC MRI (p = 0.047). Conclusion MRI is an accurate tool for evaluating pCR and residual tumor size in breast cancer patients who receive NAC. Tumor subtype and initial MRI features affect the accuracy of MRI.

• Journal of the Korean Society of Radiology
• /
• v.81 no.6
• /
• pp.1436-1447
• /
• 2020

Purpose To investigate the clinical and CT features at admission to predict the progression to necrotizing pancreatitis (NP) in patients initially diagnosed with interstitial edematous pancreatitis (IEP). Materials and Methods Patients with IEP who underwent contrast-enhanced CT at admission and follow-up CT (< 14 days) were included (n = 178). Two radiologists performed a consensus review of follow-up CT scans and diagnosed the type of acute pancreatitis as IEP or NP. Laboratory findings at admission were recorded. Clinical, CT, and laboratory findings were compared between the IEP-IEP group and IEP-NP group using the chi-square test and the t-test. Multivariate analysis was also performed. Results There were 112 and 66 patients in the IEP-IEP and the IEP-NP groups, respectively. The proportion of patients with alcohol etiology was significantly larger in the IEP-NP group. Among the CT findings, the presence of peripancreatic fluid and heterogeneous parenchymal enhancement were more frequently observed in the IEP-NP group. Among the laboratory variables, serum C-reactive protein levels and white blood cell counts were significantly higher in the IEP-NP group. Multivariate analysis revealed that the presence of peripancreatic fluid and heterogeneous parenchymal enhancement were significant findings distinguishing the two groups. Conclusion CT findings, such as the presence of peripancreatic fluid and heterogeneous pancreatic parenchymal enhancement, may be helpful in predicting the progression to NP in patients initially diagnosed with IEP.

• Journal of the Korean Society of Radiology
• /
• v.81 no.2
• /
• pp.395-408
• /
• 2020

Purpose To evaluate the value of clinicopathologic factors and imaging features of primary breast cancer in predicting early recurrence after the primary treatment. Materials and Methods We enrolled 480 patients who had been followed-up after breast-conserving surgery and adjuvant therapy from January 2010 to December 2014 at our hospital. Early recurrence was defined as recurrence within 3 years after completion of primary treatment, and univariate and multivariate logistic regression analyses were performed to determine the clinicopathologic and imaging predictive factors of early recurrence. Results In the univariate analysis, among the clinicopathologic factors, advanced stage (p = 0.021), high histologic grade (p < 0.001), estrogen receptor negative (p = 0.002), high Ki-67 proliferation index (p = 0.017), and triple-negative breast cancer (p = 0.019), and among the imaging features, multifocality (p < 0.001), vessels in the rim on Doppler ultrasonography (US) (p = 0.012), and rim enhancement (p < 0.001) on magnetic resonance imaging of the breast were significantly associated with early recurrence. In the multivariate analysis, advanced stage [odds ratio (OR) = 3.47; 95% confidence interval (CI) 1.12-10.73; p = 0.031] and vessels in the rim on Doppler US (OR = 3.32; 95% CI 1.38-8.02; p = 0.008) were the independent predictive factors of early recurrence. Conclusion Vascular findings in the rim of the primary breast cancer on Doppler US before treatment is a radiologic independent predictive factor of early recurrence after the primary treatment.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.4
• /
• pp.685-698
• /
• 2023

This study aimed to identify binge-eating behavior and food addiction in Korean population and to determine their associations with obesity, eating behaviors, mental health and cognitive characteristics. We collected clinical questionnaire scores related to eating problems (e.g. binge eating, food addiction, food cravings), mental health (e.g. depression), and cognitive functions (e.g. impulsivity, emotion regulation) in 257 Korean adults in the normal and the obese weight ranges. Binge-eating and food addiction were most frequent in obese women (binge-eating: 46.6%, food addiction: 29.3%) when we divided the participants into 4 groups depending on gender and obesity status. The independence test using the data with propensity score matching confirmed that binge-eating and food addiction were more prevalent in obese individuals. Finally, we constructed the logistic regression models using forward selection method to evaluate the influence of various clinical questionnaire scores on binge-eating and food addiction respectively. Binge-eating was significantly associated with the clinical scales of eating disorders, food craving, state anxiety, and emotion regulation (cognitive reappraisal) as well as food addiction. Food addiction demonstrated the significant effect of food craving, binge-eating, the interaction of obesity and age, and years of education. In conclusion, we found that binge-eating and food addiction are much more frequent in females and obese individuals. Both binge-eating and food addiction commonly involved eating problems (e.g. food craving), but there was difference in mental health and cognitive risk factors. Therefore, it is required to distinguish food addiction from binge-eating and investigate intrinsic and environmental risk factors for each pathology.

• Journal of the Korean Society of Radiology
• /
• v.18 no.3
• /
• pp.187-201
• /
• 2024

Osteoporosis is a major health issue globally, often remaining undetected until a fracture occurs. To facilitate early detection, deep learning (DL) models were developed to classify osteoporosis using abdominal computed tomography (CT) scans. This study was conducted using retrospectively collected data from 3,012 contrast-enhanced abdominal CT scans. The DL models developed in this study were constructed for using image data, demographic/clinical information, and multi-modality data, respectively. Patients were categorized into the normal, osteopenia, and osteoporosis groups based on their T-scores, obtained from dual-energy X-ray absorptiometry, into normal, osteopenia, and osteoporosis groups. The models showed high accuracy and effectiveness, with the combined data model performing the best, achieving an area under the receiver operating characteristic curve of 0.94 and an accuracy of 0.80. The image-based model also performed well, while the demographic data model had lower accuracy and effectiveness. In addition, the DL model was interpreted by gradient-weighted class activation mapping (Grad-CAM) to highlight clinically relevant features in the images, revealing the femoral neck as a common site for fractures. The study shows that DL can accurately identify osteoporosis stages from clinical data, indicating the potential of abdominal CT scans in early osteoporosis detection and reducing fracture risks with prompt treatment.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.69 no.1
• /
• pp.25-33
• /
• 2024

This experiment was conducted at the affiliated farm of the Suncheon University from 2022 to 2023 to investigate the growth, yield, and quality characteristics of soybeans based on the treatment method of Methyl Sulfony Methane (MSM) for the establishment of stable production practices. In the initial investigation of growth characteristics in 2022, an increasing trend in characteristics such as plant height, stem thickness, and branching index was observed as the treatment concentration increased from 50% to 200%. Yield components also followed the same trend, with the basal fertilization + top dressing 3 times at 200% treatment showing the highest yield at 355 kg·10a^-1, with the highest number of pods. In the subsequent study to determine the optimal concentration exceeding 200% in 2023, growth characteristics showed a trend of 400% > 200% > 800%. The basal fertilization + top dressing 3 times at 400% treatment exhibited the longest plant height (106.7 cm) and the most branches (6). In terms of seed quality, this treatment also had the highest proportion (66.9%) of seeds with a diameter over 6.7 mm. Additionally, in yield components such as pods, seeds per pod, and 100-seed weight, the basal fertilization + top dressing 3 times at 400% treatment showed the highest values, resulting in a maximum yield of 374 kg·10a^-1, representing a 23.4% increase compared to the control. Therefore, for the optimal production of high-quality soybeans, it is recommended to apply the treatment of basal fertilization + top dressing 3 times at 400% concentration, with top dressing occurring at 30-day intervals before harvest.

• The Journal of Korean Academy of Prosthodontics
• /
• v.62 no.2
• /
• pp.95-103
• /
• 2024

Purpose. With the advancement of digital technology, 3D printing is being utilized in the fabrication of denture base. Nevertheless, increasing microbial adhesion to the surface of denture base has been reported as the disadvantage of 3D-printed denture base. The purpose of this study is to investigate the antifungal properties and flexural strength of 3D-printed denture base resin according to the different contents of titanium dioxide nanoparticles. Materials and methods. Titanium dioxide nanoparticles were mixed with the 3D printing resin at the ratios of 0.5, 1, 1.5, and 2 wt%. Twenty specimens per each group were printed in the form of cylindrical shape (diameter: 20 mm, height: 3 mm) to evaluate antifungal properties. Ten specimens from each group underwent polishing using autogrinder, while the remaining ten specimens did not. Candida albicans in hyphae form was inoculated onto each specimen, optical density and colony-forming unit were analyzed. The surface of the specimen was observed using scanning electron microscopy. To evaluate the flexural strength, twenty specimens per each group were 3D printed in the form of rectangular prism shape (length: 64 mm, height: 10 mm, width: 3 mm) and three-point bending tests were conducted using universal testing machine according to ISO 20795-1. Results. Colony-forming unit of C.albicans and optical density of culture medium showed no difference between non-polished groups, but decreased in the polished groups at concentration of 1, 1.5, 2 wt% titanium dioxide nanoparticles. Flexural strength increased with titanium dioxide nanoparticle at concentration of 0.5, 1, 1.5 wt%, but decreased at 2 wt% compared to 1.5 wt%. Conclusion. When 1.5 wt% of titanium dioxide nanoparticles were added to the 3D-printed denture base resin with polishing, antifungal properties were increased.

• Journal of the Korean Society of Radiology
• /
• v.84 no.5
• /
• pp.1066-1079
• /
• 2023

Purpose Distinguishing intradural extramedullary (IDEM) spinal ependymoma from myxopapillary ependymoma is challenging due to the location of IDEM spinal ependymoma. This study aimed to investigate the utility of clinical and MR imaging features for differentiating between IDEM spinal and myxopapillary ependymomas. Materials and Methods We compared tumor size, longitudinal/axial location, enhancement degree/pattern, tumor margin, signal intensity (SI) of the tumor on T2-weighted images and T1-weighted image (T1WI), increased cerebrospinal fluid (CSF) SI caudal to the tumor on T1WI, and CSF dissemination of pathologically confirmed 12 IDEM spinal and 10 myxopapillary ependymomas. Furthermore, classification and regression tree (CART) was performed to identify the clinical and MR features for differentiating between IDEM spinal and myxopapillary ependymomas. Results Patients with IDEM spinal ependymomas were older than those with myxopapillary ependymomas (48 years vs. 29.5 years, p < 0.05). A high SI of the tumor on T1W1 was more frequently observed in IDEM spinal ependymomas than in myxopapillary ependymomas (p = 0.02). Conversely, myxopapillary ependymomas show CSF dissemination. Increased CSF SI caudal to the tumor on T1WI was observed more frequently in myxopapillary ependymomas than in IDEM spinal ependymomas (p < 0.05). Dissemination to the CSF space and increased CSF SI caudal to the tumor on T1WI were the most important variables in CART analysis. Conclusion Clinical and radiological variables may help differentiate between IDEM spinal and myxopapillary ependymomas.