Objective: To evaluate the diagnostic performance of the “probable hepatocellular carcinoma (HCC)” category in the Korean Liver Cancer Association-National Cancer Center (KLCA-NCC) v2022 guidelines. Materials and Methods: This multicenter retrospective study included patients at risk of HCC who underwent gadoxetic acid-enhanced MRI between January 2015 and June 2018; a subgroup of these patients also underwent liver CT. Eligible patients had at least one non-cystic lesion (≥10 mm) with a reference standard. Four radiologists interpreted the images independently and the results were pooled. The performance of “definite HCC” and “probable HCC” together and “probable HCC” alone were compared between v2018 and v2022. Results: A total of 2,237 patients (1,666 men; mean age, 59 ± 11 years) with 2,445 lesions were included. In v2022, 1.5% (143/9,780) of the lesions were additionally categorized as “probable HCC” by four reviewers on MRI; among these, 104 lesions were not HCCs. Focal nodular hyperplasia (FNH) or FNH-like nodules constituted 90.4% (94/104) of the false positives. When “definite HCC” and “probable HCC” were combined, v2022 showed higher sensitivity (83.7% [5,670/6,776] vs. 83.1% [5,631/6,776]) but lower specificity (77.1% [2,316/3,004] vs. 80.6% [2,420/3,004]) than v2018 (P < 0.001). For “probable HCC” alone, v2022 showed a lower positive predictive value (PPV) than v2018 (64.1% [373/582] vs. 76.1% [334/439], P < 0.001). In v2022, lesions with non-rim arterial-phase hyperenhancement (APHE) showed a lower PPV than those without APHE (42.3% [91/215] vs. 76.8% [282/367], P < 0.001). In the CT subgroup (n = 1,590), 1.6% (99/6,360) of the lesions were reassessed as “probable HCC,” and its PPV was 83.8% (83/99) in v2022 whereas no lesions were classified as “probable HCC” under v2018. Conclusion The revised “probable HCC” category in the KLCA-NCC v2022 aligns with updates in the diagnostic flow, demonstrating acceptable performance on MRI and CT. Notably, FNH or FNH-like nodules can be misclassified as “probable HCC” when MRI is used.

Objective: To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI). Materials and Methods: A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm 2 was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive.The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC). Results: Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4–79.9), 90.8% (95% CI: 85.6–94.2), and 83.5% (95% CI: 78.6–87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8–97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9–89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1–79.4; P = 0.58) was observed. Regarding inter-reader agreement, the κ values were 0.57 (95% CI: 0.52–0.63) before training and 0.68 (95% CI: 0.62–0.74) after training, with a difference of 0.11 (95% CI: 0.02–0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69–0.74) before training and 0.79 (95% CI: 0.76–0.80) after training (P = 0.002). Conclusion Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.

Background: Sutureless valves are widely used in aortic valve replacement surgery, with Perceval valves and Intuity valves being particularly prominent. However, concerns have been raised about postoperative thrombocytopenia with Perceval valves (Corcym, UK). We conducted a comparative analysis with the Intuity valve (Edwards Lifesciences, USA), and assessed how thrombocytopenia affected patient and transfusion outcomes. Methods: Among 595 patients who underwent aortic valve replacement from June 2016 to March 2023, sutureless valves were used in 53 (Perceval: n=23; Intuity: n=30). Platelet counts were monitored during hospitalization and outpatient visits. Daily platelet count changes were compared between groups, and the results from patients who underwent procedures using Carpentier Edwards Perimount Magna valves were used as a reference group. Results: Compared to the Intuity group, the Perceval group showed a significantly higher amount of platelet transfusion (5.48±1.64 packs vs. 0.60±0.44 packs, p=0.008). During the postoperative period, severe thrombocytopenia (<50,000/μL) was significantly more prevalent in the Perceval group (56.5%, n=13) than in the Intuity group (6.7%, n=2). After initial postoperative depletion, daily platelet counts increased, with significant differences observed in the extent of improvement between the Perceval and Intuity groups (p<0.001).However, there was no significant difference in early mortality or the incidence of neurological complications between the 2 groups. Conclusion The severity of postoperative thrombocytopenia differed significantly between the Perceval and Intuity valves. The Perceval group showed a significantly higher prevalence of severe thrombocytopenia and higher platelet transfusion volumes. However, thrombocytopenia gradually recovered during the postoperative period in both groups, and the early outcomes were similar in both groups.

Background: A clear and precise definition of the “intended use” in developing new medical devices can determine the success of entering the healthcare market. For this, practical collaboration between the clinical and engineering experts is necessary, and an appropriate tool is required for effective information collection and decision-making in the process. Methods: The Korean Academy of Medical Sciences, in cooperation with the Korean Medical Device Development Fund, implemented the Healthcare Experts’ Advisory Unit and Support (HAUS) program to match advisory clinical experts in medical device development projects. Three and five collaborative academic conferences were held in 2022 and 2023 to raise awareness of the HAUS program. In the consultation meeting, checklists were used to facilitate communications and satisfaction surveys were conducted afterward. Then, the results of the consultation meetings were compiled to build an integrated document. Results: The HAUS program was conducted with a gradually increasing number of consultation sessions from 31 in 2021 to 128 in 2023. The medical device development teams (development teams) expressed a higher level of satisfaction (91.4% to 100%) compared to the advisors (clinical experts) (78.6% to 100%) across the survey items. Based on the experiences and observations of the HAUS consultation meetings, the “Clinical Unmet Needs-based Intended Use Establishment (CLUE) templates” were developed, which were purposes to improve communication efficiency and to support a systematic approach in establishing the intended use. The CLUE process comprises four main stages for processing:Stage 1, Initial Concept; Stage 2, Expert Consultation; Stage 3, Decision-making; and Stage 4, Intended Use. Conclusion The HAUS program seemed to be helpful for the development teams by providing opinions of clinical experts. And the resultant product, the CLUE templates have been proposed to facilitate collaboration between the development teams and the advisors and to define robust clinical intended use.

Background: A clear and precise definition of the “intended use” in developing new medical devices can determine the success of entering the healthcare market. For this, practical collaboration between the clinical and engineering experts is necessary, and an appropriate tool is required for effective information collection and decision-making in the process. Methods: The Korean Academy of Medical Sciences, in cooperation with the Korean Medical Device Development Fund, implemented the Healthcare Experts’ Advisory Unit and Support (HAUS) program to match advisory clinical experts in medical device development projects. Three and five collaborative academic conferences were held in 2022 and 2023 to raise awareness of the HAUS program. In the consultation meeting, checklists were used to facilitate communications and satisfaction surveys were conducted afterward. Then, the results of the consultation meetings were compiled to build an integrated document. Results: The HAUS program was conducted with a gradually increasing number of consultation sessions from 31 in 2021 to 128 in 2023. The medical device development teams (development teams) expressed a higher level of satisfaction (91.4% to 100%) compared to the advisors (clinical experts) (78.6% to 100%) across the survey items. Based on the experiences and observations of the HAUS consultation meetings, the “Clinical Unmet Needs-based Intended Use Establishment (CLUE) templates” were developed, which were purposes to improve communication efficiency and to support a systematic approach in establishing the intended use. The CLUE process comprises four main stages for processing:Stage 1, Initial Concept; Stage 2, Expert Consultation; Stage 3, Decision-making; and Stage 4, Intended Use. Conclusion The HAUS program seemed to be helpful for the development teams by providing opinions of clinical experts. And the resultant product, the CLUE templates have been proposed to facilitate collaboration between the development teams and the advisors and to define robust clinical intended use.

Background: A clear and precise definition of the “intended use” in developing new medical devices can determine the success of entering the healthcare market. For this, practical collaboration between the clinical and engineering experts is necessary, and an appropriate tool is required for effective information collection and decision-making in the process. Methods: The Korean Academy of Medical Sciences, in cooperation with the Korean Medical Device Development Fund, implemented the Healthcare Experts’ Advisory Unit and Support (HAUS) program to match advisory clinical experts in medical device development projects. Three and five collaborative academic conferences were held in 2022 and 2023 to raise awareness of the HAUS program. In the consultation meeting, checklists were used to facilitate communications and satisfaction surveys were conducted afterward. Then, the results of the consultation meetings were compiled to build an integrated document. Results: The HAUS program was conducted with a gradually increasing number of consultation sessions from 31 in 2021 to 128 in 2023. The medical device development teams (development teams) expressed a higher level of satisfaction (91.4% to 100%) compared to the advisors (clinical experts) (78.6% to 100%) across the survey items. Based on the experiences and observations of the HAUS consultation meetings, the “Clinical Unmet Needs-based Intended Use Establishment (CLUE) templates” were developed, which were purposes to improve communication efficiency and to support a systematic approach in establishing the intended use. The CLUE process comprises four main stages for processing:Stage 1, Initial Concept; Stage 2, Expert Consultation; Stage 3, Decision-making; and Stage 4, Intended Use. Conclusion The HAUS program seemed to be helpful for the development teams by providing opinions of clinical experts. And the resultant product, the CLUE templates have been proposed to facilitate collaboration between the development teams and the advisors and to define robust clinical intended use.

Background: A clear and precise definition of the “intended use” in developing new medical devices can determine the success of entering the healthcare market. For this, practical collaboration between the clinical and engineering experts is necessary, and an appropriate tool is required for effective information collection and decision-making in the process. Methods: The Korean Academy of Medical Sciences, in cooperation with the Korean Medical Device Development Fund, implemented the Healthcare Experts’ Advisory Unit and Support (HAUS) program to match advisory clinical experts in medical device development projects. Three and five collaborative academic conferences were held in 2022 and 2023 to raise awareness of the HAUS program. In the consultation meeting, checklists were used to facilitate communications and satisfaction surveys were conducted afterward. Then, the results of the consultation meetings were compiled to build an integrated document. Results: The HAUS program was conducted with a gradually increasing number of consultation sessions from 31 in 2021 to 128 in 2023. The medical device development teams (development teams) expressed a higher level of satisfaction (91.4% to 100%) compared to the advisors (clinical experts) (78.6% to 100%) across the survey items. Based on the experiences and observations of the HAUS consultation meetings, the “Clinical Unmet Needs-based Intended Use Establishment (CLUE) templates” were developed, which were purposes to improve communication efficiency and to support a systematic approach in establishing the intended use. The CLUE process comprises four main stages for processing:Stage 1, Initial Concept; Stage 2, Expert Consultation; Stage 3, Decision-making; and Stage 4, Intended Use. Conclusion The HAUS program seemed to be helpful for the development teams by providing opinions of clinical experts. And the resultant product, the CLUE templates have been proposed to facilitate collaboration between the development teams and the advisors and to define robust clinical intended use.

Background: More than half of acne patients have truncal acne on their chest, back, and shoulders. However, since most studies on acne have focused on the face, data on clinical characteristics and proper management for truncal acne are insufficient. Objective: To establish a Korean Acne Rosacea Society (KARS) consensus for experts’ perception and treatment patterns of truncal acne. Methods: We conducted two rounds of the Dephi technique to gather expert opinion and reach a consensus on truncal acne. The first round comprised 48 questionnaires focusing on various aspects such as epidemiology, clinical features, diagnosis, treatment, prognosis and more, while second rounds consisted of 26 questionnaires. Results: A total of 36 dermatologists (36/38 KARS members, 94.7%) completed this survey. In the first-round survey, consensus was reached on 20 out of the 48 questions (41.7%). In the secondround questionnaire, consensus was achieved on 9 of the 26 questions (34.6%). The most unresponsive lesion to truncal acne treatment was scars (atrophic/hypertrophic). The most commonly used treatments for each non-inflammatory and inflammatory truncal acne lesions were selected to use topical retinoids (78.1% of the responders) and oral antibiotics (93.8% of the responders). Conclusion Our study has yielded valuable insights into the epidemiology, clinical manifestations, diagnosis, treatment, and quality of life of patients with truncal acne. We anticipate that this study will inspire further comprehensive research for individuals with truncal acne.

Background/Aims: Gastrointestinal (GI) bezoars are relatively rare diseases with clinical characteristics and treatment modalities that depend on the location of the bezoars. This study evaluated the clinical characteristics and treatment outcomes in patients with GI bezoars. Methods: Seventy-five patients diagnosed with GI bezoars were enrolled in this study. Data were collected on the demographic and clinical characteristics and the characteristics of the bezoars, such as type, size, location, treatment modality, and clinical outcomes. Results: Among the 75 patients (mean age 71.2 years, 38 males), 32 (42.6%) had a history of intra-abdominal surgery. Hypertension (43%) and diabetes (30%) were common morbidities. The common location of the bezoars was the stomach in 33 (44%) and the small intestine in 33 (44%). Non-surgical management, including adequate hydration, chemical dissolution, and endoscopic removal, was successful in 2/2 patients with esophageal bezoars, 26/33 patients with gastric bezoars, 7/9 patients with duodenal bezoars, and 20/33 patients with small intestinal bezoars. The remaining patients had undergone surgical management. Conclusions The management of GI bezoars requires multidisciplinary approaches, including the appropriate correction of fluid and electrolyte imbalances, chemical dissolution, and endoscopic and surgical treatments. (Korean J Gastroenterol 2023;81:253-258)

Methods: Computed tomographic scans of a total of 50 male and 50 female patients were utilized. The placement of C7 laminar screws was activated employing the new and old trajectories. The success rate, the causes of failure, and the maximum allowable length of each trajectory were compared. Results: Employing the new trajectory, the success rates of the unilaminar and bilaminar screws were 93% and 83%, respectively, which were significantly better than the old trajectory (80%, p<0.0001 and 70%, p=0.0003). The most prevalent cause of failure was laminar cortical breach followed by facet joint violation. The new trajectory also offered significantly longer maximum allowable screw length in unilaminar (32.5±4.3 mm vs. 26.5±2.6 mm, p<0.001), bilaminar cephalic (29.5±3.8 mm vs. 25.9±2.6 mm, p<0.0001) and bilaminar caudal (33.1±2.6 mm vs. 25.8±3.1 mm, p<0.001) screws than the old trajectory. With the new and old trajectories, 70% vs. 6% of unilaminar, 60% vs. 2% of bilaminar caudal, and 32% vs. 4% of bilaminar cephalic screws could be protracted perfectly into the corresponding lateral mass without any laminar cortical or facet joint violation (p<0.0001). Conclusions The novel trajectory possesses a substantially higher success rate, longer maximum allowable screw length, and higher chance to be extended into the lateral mass (a condition known as a lamino-lateral mass screw) than the old trajectory.