Purpose: This study evaluated how artificial intelligence-based computer-assisted diagnosis (AICAD) for breast ultrasonography (US) influences diagnostic performance and agreement between radiologists with varying experience levels in different workflows. Methods: Images of 492 breast lesions (200 malignant and 292 benign masses) in 472 women taken from April 2017 to June 2018 were included. Six radiologists (three inexperienced [<1 year of experience] and three experienced [10-15 years of experience]) individually reviewed US images with and without the aid of AI-CAD, first sequentially and then simultaneously. Diagnostic performance and interobserver agreement were calculated and compared between radiologists and AI-CAD. Results: After implementing AI-CAD, the specificity, positive predictive value (PPV), and accuracy significantly improved, regardless of experience and workflow (all P<0.001, respectively). The overall area under the receiver operating characteristic curve significantly increased in simultaneous reading, but only for inexperienced radiologists. The agreement for Breast Imaging Reporting and Database System (BI-RADS) descriptors generally increased when AI-CAD was used (κ=0.29-0.63 to 0.35-0.73). Inexperienced radiologists tended to concede to AI-CAD results more easily than experienced radiologists, especially in simultaneous reading (P<0.001). The conversion rates for final assessment changes from BI-RADS 2 or 3 to BI-RADS higher than 4a or vice versa were also significantly higher in simultaneous reading than sequential reading (overall, 15.8% and 6.2%, respectively; P<0.001) for both inexperienced and experienced radiologists. Conclusion Using AI-CAD to interpret breast US improved the specificity, PPV, and accuracy of radiologists regardless of experience level. AI-CAD may work better in simultaneous reading to improve diagnostic performance and agreement between radiologists, especially for inexperienced radiologists.

Purpose: To derive the optimized intraocular lens (IOL) constants from automated and manifest refraction after cataract surgery in Korean patients, and to evaluate whether there is a difference in optimized IOL constants according to the refraction method. Methods: This retrospective multicenter cohort study enrolled 4,103 eyes of 4,103 patients who underwent phacoemulsification and in-the-bag IOL implantation at 18 institutes. Optimized IOL constants for the SRK/T, Holladay, Hoffer Q, and Haigis formulas were calculated via autorefraction or manifest refraction of samples using the same biometry and IOL. The IOL constants derived from autorefraction and manifest refraction were compared. Results: Of the 4,103 eyes, the majority (62.9%) were measured with an IOLMaster 500 followed by an IOLMaster 700 (15.2%). A total of 33 types of IOLs were used, and the Tecnis ZCB00 was the most frequently used (53.0%). There was no statistically significant difference in IOL constants derived from autorefraction and manifest refraction when IOL constants were optimized with a large number of study subjects. On the other hand, optimized IOL constants derived from autorefraction were significantly smaller than those from manifest refraction when the number of subjects was small. Conclusions It became possible to use the IOL constants optimized from Koreans to calculate the IOL power. However, if the IOL constant is optimized using autorefraction in a small sample group, the IOL constant tends to be small, which may lead to refractive error after surgery.

Background: This study aimed to investigate the recent prevalence, management, and comorbidities of diabetes among Korean adults aged ≥30 years by analyzing nationally representative data. Methods: This study used data from the Korea National Health and Nutrition Examination Survey from 2016 to 2018, and the percentage and total number of people ≥30 years of age with diabetes and impaired fasting glucose (IFG) were estimated. Results: In 2018, 13.8% of Korean adults aged ≥30 years had diabetes, and adults aged ≥65 years showed a prevalence rate of 28%. The prevalence of IFG was 26.9% in adults aged ≥30 years. From 2016 to 2018, 35% of the subjects with diabetes were not aware of their condition. Regarding comorbidities, 53.2% and 61.3% were obese and hypertensive, respectively, and 72% had hypercholesterolemia as defined by low-density lipoprotein cholesterol (LDL-C) ≥100 mg/dL in people with diabetes. Of the subjects with diabetes, 43.7% had both hypertension and hypercholesterolemia. With regard to glycemic control, only 28.3% reached the target level of <6.5%. Moreover, only 11.5% of subjects with diabetes met all three targets of glycosylated hemoglobin, blood pressure, and LDL-C. The percentage of energy intake from carbohydrates was higher in diabetes patients than in those without diabetes, while that from protein and fat was lower in subjects with diabetes. Conclusion The high prevalence and low control rate of diabetes and its comorbidities in Korean adults were confirmed. More stringent efforts are needed to improve the comprehensive management of diabetes to reduce diabetes-related morbidity and mortality.

The coronavirus disease (COVID-19) outbreak has reached global pandemic status as announced by the World HealthOrganization, which currently recommends reverse transcription polymerase chain reaction (RT-PCR) as the standard diagnostictool. However, although the RT-PCR test results may be found negative, there are cases that are found positive for COVID-19pneumonia on computed tomography (CT) scan. CT is also useful in assessing the severity of COVID-19 pneumonia. Whenclinicians desire a CT scan of a patient with COVID-19 to monitor treatment response, a safe method for patient transport isnecessary. To address the engagement of medical resources necessary to transport a patient with COVID-19, our institutionhas implemented the use of mobile CT. Therefore, we report two cases of COVID-19 pneumonia evaluated by using mobilecone-beam CT. Although mobile cone-beam CT had some limitations regarding its image quality such as scatter noise, motionand streak artifacts, and limited field of view compared with conventional multi-detector CT, both cases had acceptable imagequality to establish the diagnosis of COVID-19 pneumonia. We report the usefulness of mobile cone-beam CT in patients withCOVID-19 pneumonia.

Purpose: Recently, non-exposure simple suturing endoscopic full-thickness resection (NESSEFTR) was developed to prevent tumor exposure to the peritoneal cavity. This study aimed to evaluate the feasibility of NESS-EFTR with sentinel basin dissection for early gastric cancer (EGC). Materials and Methods: This was the prospective SENORITA 3 pilot. From July 2017 to January 2018, 20 patients with EGC smaller than 3 cm without an absolute indication for endoscopic submucosal dissection were enrolled. The sentinel basin was detected using Tc 99m -phytate and indocyanine green, and the NESS-EFTR procedure was performed when all sentinel basin nodes were tumor-free on frozen pathologic examination. We evaluated the complete resection and intraoperative perforation rates as well as the incidence of postoperative complications. Results: Among the 20 enrolled patients, one dropped out due to large tumor size, while another underwent conventional laparoscopic gastrectomy due to metastatic sentinel lymph nodes. All NESS-EFTR procedures were performed in 17 of the 18 other patients (94.4%) without conversion, and the complete resection rate was 83.3% (15/18). The intraoperative perforation rate was 27.8% (5/18), and endoscopic clipping or laparoscopic suturing or stapling was performed at the perforation site. There was one case of postoperative complications treated with endoscopic clipping; the others were discharged without any event. Conclusions NESS-EFTR with sentinel basin dissection is a technically challenging procedure that obtains safe margins, prevents intraoperative perforation, and may be a treatment option for EGC after additional experience.

PURPOSE: The aim of this study was to evaluate and compare the diagnostic performance of grayscale ultrasonography (US), US elastography, and US computer-aided diagnosis (US-CAD) in the differential diagnosis of breast masses. METHODS: A total of 193 breast masses in 175 consecutive women (mean age, 46.4 years) from June to August 2015 were included. US and elastography images were obtained and recorded. A US-CAD system was applied to the grayscale sonograms, which were automatically analyzed and visualized in order to generate a final assessment. The final assessments of breast masses were based on the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) categories, while elasticity scores were assigned using a 5-point scoring system. The diagnostic performance of grayscale US, elastography, and US-CAD was calculated and compared. RESULTS: Of the 193 breast masses, 120 (62.2%) were benign and 73 (37.8%) were malignant. Breast masses had significantly higher rates of malignancy in BI-RADS categories 4c and 5, elastography patterns 4 and 5, and when the US-CAD assessment was possibly malignant (all P<0.001). Elastography had higher specificity (40.8%, P=0.042) than grayscale US. US-CAD showed the highest specificity (67.5%), positive predictive value (PPV) (61.4%), accuracy (74.1%), and area under the curve (AUC) (0.762, all P<0.05) among the three diagnostic tools. CONCLUSION: US-CAD had higher values for specificity, PPV, accuracy, and AUC than grayscale US or elastography. Computer-based analysis based on the morphologic features of US may be very useful in improving the diagnostic performance of breast US.
Area Under Curve ; Breast* ; Diagnosis* ; Diagnosis, Computer-Assisted ; Diagnosis, Differential ; Elasticity ; Elasticity Imaging Techniques* ; Female ; Humans ; Information Systems ; Sensitivity and Specificity ; Ultrasonography ; Ultrasonography, Mammary*

BACKGROUND: The impact of HLA and KIR ligand mismatching on the outcome of hematopoietic stem cell transplantation (HSCT) remains unclear. Previous reports have identified considerable ethnic differences in the impact of HLA and KIR ligand mismatches, as well as KIR ligand status, on HSCT; however, to date, no data has been acquired in Korean adult patients. METHODS: We investigated the association of high-resolution HLA matching on five loci (HLA-A, -B, -C, -DRB1, and -DQB1), KIR ligand mismatching, and KIR ligand status on the outcome of allogeneic HSCT from unrelated donors in 154 Korean adult patients treated at Seoul National University Hospital. RESULTS: In a multivariate analysis, less than 9/10 allelic matches in five HLA loci was an independent risk factor for acute graft-versus-host disease (GVHD) (grade II to IV) (P=0.019, odds ratio [OR]=2.7). In addition, HLA-A allele mismatching was increasingly prevalent in patients with acute GVHD compared to patients without (61.9% vs. 34.5%, P=0.06). For KIR ligand status, the patient and donor combination of both C1/C1 ligands showed better event-free and overall survival than combinations with C2 ligand patients or donors (P=0.048, P=0.034, respectively) by log-rank test. CONCLUSIONS: Korean adult transplant patients with less than 9 of 10 HLA allele matches in the HLA-A, -B, -C, -DRB1, and DQB1 loci have a higher likelihood of developing acute GVHD (grade II to IV). Impact of KIR ligand status on clinical outcome should be further studied in a larger patient population.
Adolescent ; Adult ; Alleles ; Female ; Genetic Loci ; Graft vs Host Disease/etiology ; HLA Antigens/*genetics/metabolism ; *Hematopoietic Stem Cell Transplantation/adverse effects/standards ; Histocompatibility Testing ; Humans ; Kaplan-Meier Estimate ; Leukemia/mortality/therapy ; Male ; Middle Aged ; Multivariate Analysis ; Receptors, KIR/*chemistry/metabolism ; Republic of Korea ; Risk Factors ; Transplantation, Homologous ; Young Adult

PURPOSE: The purpose of this study was to evaluate efficacy and toxicity of irinotecan, leucovorin and 5-fluorouracil (FOLFIRI) as second-line treatment after failure of oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) for advanced gastric cancer. MATERIALS AND METHODS: Patients who received modified FOLFOX-4 as first-line treatment and then received sequential modified FOLFIRI for disease progression were included in this study. The modified FOLFIRI regimen consisted of irinotecan 150 mg/m2 in a 90-minute intravenous infusion on day 1, leucovorin (LV) 20 mg/m2 and 5-fluorouracil (5-FU) 400 mg/m2 as a bolus followed by 600 mg/m2 as a 22-hour infusion on days 1 and 2 with the same dose of 5-FU/LV of modified FOLFOX-4 every 2 weeks. RESULTS: A total of 32 patients received 126 courses of FOLFIRI chemotherapy. No complete response was achieved. Three patients (9.4%; 95% confidence interval [CI], 0 to 20.1%) achieved partial response, whereas 11 (34.4%; 95% CI, 17.0 to 51.8%) patients showed stable disease. Disease control rate (complete response, partial responses and stable diseases) was 43.8% (95% CI, 25.6 to 61.9%) and median follow up duration was 11.3 months (range, 2.23 to 37.9 months). Median time to progression was 2 months (95% CI, 1.49 to 2.51 months), and median overall survival from the start of FOLFIRI was 5.84 months (95% CI, 4.34 to 7.34 months). Toxicities were tolerable. CONCLUSION: Modified FOLFIRI as second-line chemotherapy after failure of the modified FOLFOX-4 in advanced gastric cancer was tolerable but showed a lower response rate. Further study about retrying 5-FU/LV with irinotecan after failure of the 5-FU/LV combined regimen is necessary in advanced gastric cancer.
Camptothecin ; Disease Progression ; Fluorouracil ; Follow-Up Studies ; Humans ; Infusions, Intravenous ; Leucovorin ; Organoplatinum Compounds ; Stomach Neoplasms

PURPOSE: The purpose of this study was to evaluate efficacy and toxicity of irinotecan, leucovorin and 5-fluorouracil (FOLFIRI) as second-line treatment after failure of oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) for advanced gastric cancer. MATERIALS AND METHODS: Patients who received modified FOLFOX-4 as first-line treatment and then received sequential modified FOLFIRI for disease progression were included in this study. The modified FOLFIRI regimen consisted of irinotecan 150 mg/m2 in a 90-minute intravenous infusion on day 1, leucovorin (LV) 20 mg/m2 and 5-fluorouracil (5-FU) 400 mg/m2 as a bolus followed by 600 mg/m2 as a 22-hour infusion on days 1 and 2 with the same dose of 5-FU/LV of modified FOLFOX-4 every 2 weeks. RESULTS: A total of 32 patients received 126 courses of FOLFIRI chemotherapy. No complete response was achieved. Three patients (9.4%; 95% confidence interval [CI], 0 to 20.1%) achieved partial response, whereas 11 (34.4%; 95% CI, 17.0 to 51.8%) patients showed stable disease. Disease control rate (complete response, partial responses and stable diseases) was 43.8% (95% CI, 25.6 to 61.9%) and median follow up duration was 11.3 months (range, 2.23 to 37.9 months). Median time to progression was 2 months (95% CI, 1.49 to 2.51 months), and median overall survival from the start of FOLFIRI was 5.84 months (95% CI, 4.34 to 7.34 months). Toxicities were tolerable. CONCLUSION: Modified FOLFIRI as second-line chemotherapy after failure of the modified FOLFOX-4 in advanced gastric cancer was tolerable but showed a lower response rate. Further study about retrying 5-FU/LV with irinotecan after failure of the 5-FU/LV combined regimen is necessary in advanced gastric cancer.
Camptothecin ; Disease Progression ; Fluorouracil ; Follow-Up Studies ; Humans ; Infusions, Intravenous ; Leucovorin ; Organoplatinum Compounds ; Stomach Neoplasms

In radiofrequency (RF) ablation for idiopathic left ventricular tachycardia (ILVT), the termination of tachycardia during RF ablation is considered a hallmark of success. However, in cases of patients with difficulty of induction of ventricular tachycardia (VT), the evaluation of procedural success can be problematic. We have observed thermal responses reflected as ventricular rhythm change to RF energy delivered on sinus rhythm for ILVT. We therefore describe the significance of repetitive ventricular responses. The study subjects were 11 ILVT patients for whom RF energy was delivered during sinus rhythm because of difficulty in re-induction of tachycardia. During each energy delivery, we focused on the occurrence of repetitive ventricular responses especially exhibiting a similar morphology to clinical VT. The repetitive ventricular responses were noted in 10 of 11 patients. Two patients received a second procedure due to the recurrence of ILVT. The mean follow-up period was 36.2+/-12.8 months. The clinical course of the remaining patients was favorable and without recurrence of ILVT. Based on the favorable clinical outcomes, ablation-induced repetitive ventricular responses with similar QRS morphology to clinical ILVT are useful markers for selecting an ablation site and could be used as an additional mapping method, termed as "thermal mapping".