Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Purpose: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

Purpose: Immunochemical fecal occult blood tests (iFOBT) have been utilized as the primary method for colorectal cancer screening within Korea's National Cancer Screening Program. This study aimed to evaluate the impact of the accreditation program for clinical laboratories and external quality assessment (EQA) programs on colorectal cancer screening. Methods: We analyzed the false-positive rates of iFOBT in colorectal cancer screening from 2016 to 2020 according to participation and performance in the Outstanding Laboratory Accreditation Program (OLAP) conducted by the Laboratory Medicine Foundation, and the External Quality Assessment programs run by the Korean Association of External Quality Assessment Service. Results: False-positive rates of iFOBT were lower among institutions accredited by OLAP (2.35%) compared with non-accredited (3.04%) and non-participating institutions (5.60%). Similarly, institutions participating in the EQA program exhibited lower false-positive rates (3.79%) compared to non-participants (7.04%). Within the iFOBT-specific EQA program, institutions that passed demonstrated the lowest false-positive rate (3.37%), while failing institutions showed the highest rate (9.07%), surpassing even non-participating institutions (6.44%). Conclusion Participation in quality management programs such as OLAP and EQA was associated with lower false-positive rates in iFOBT for colorectal cancer screening. These findings suggest that quality management initiatives can increase the accuracy of iFOBT, potentially improving the effectiveness of colorectal cancer screening programs, and reducing unnecessary follow-up procedures and associated healthcare costs.

Purpose: To identify US findings suggestive of malignancy in thyroid nodules with follicular lesions of undetermined significance (FLUS) or follicular neoplasm (FN) on fine-needle aspiration cytology (FNAC) and evaluate the diagnostic performance. Materials and Methods: Seventy FLUS (n = 57) or FN (n = 13) nodules on FNAC that underwent surgical excision between February 2018 and November 2020 were selected. US findings were retrospectively reviewed. Orientation, margin, echogenicity, calcification, additional findings of the rim, echogenicity, heterogeneity of the solid portion, and the ratio of anterior posterior diameter to lateral diameter (criteria) were assessed. The diagnostic performances of US findings, criteria, and the Korean Society of Thyroid Radiology Thyroid Imaging Reporting and Data System (K-TIRADS) were evaluated using logistic regression analysis. Results: Microcalcification, homogeneous solid echotexture, and thickened rims were suggestive of malignancy. Our criteria showed a highest area under the ROC curve (AUC) value of 0.771, sensitivity of 97.14%, accuracy of 77.14%, positive predictive value of 93.33%, negative predictive value of 95.24%, and specificity of 97.14%. The criteria showed a significantly higher AUC value than K-TIRADS. Conclusion US findings of homogenous solid portions, thick rims, and microcalcifications suggested malignancy in nodules with FLUS or FN on FNAC. These additional US findings could improve the diagnostic performance of K-TIRADS.

The introduction of anti-amyloid therapies for Alzheimer’s disease (AD), such as lecanemab (Lequembi®), which was recently approved in Korea, necessitates careful monitoring for amyloid-related imaging abnormalities (ARIA) using brain MRI. To optimize ARIA monitoring in Korean clinical settings, the Korean Society of Neuroradiology (KSNR) and the Age and Neurodegeneration Imaging (ANDI) Study Group proposed MRI protocol recommendations on essential MR sequences, MRI acquisition parameters, timing and condition of MRI examinations, and essential details to provide a scientific basis for maximizing the safety and efficacy of AD treatment. A customized, standardized MRI protocol focusing on Korea’s healthcare environment can improve ARIA management and ensure patient safety through early detection of potential anti-amyloid therapy side effects, thereby enhancing treatment quality.

Background: The Rapid-O2 oxygen insufflation device® (Rapid-O2) was designed primarily for rescue oxygenation in cannot intubate, cannot oxygenate (CICO) events; thus, hypercapnia is inevitable. Rapid-O2 was modified to enhance ventilation using the Venturi effect during expiration. Methods: To determine the most effective combination of inner catheters (20 gauge [G], 18 G, 16 G, 14 G, and 2-mm inner diameter [ID] transtracheal catheter [TTC]) and insufflation catheters (16 G, 14 G, and 2-mm ID TTC) for achieving optimum ventilation, insufflating and expiratory flows were measured at an oxygen flow rate of 15 L/min. The insufflating and expiratory pressures were measured at 6–15 L/min. The flows and pressures were measured using a gas flow analyzer. The insufflating and expiratory times were measured using a trachea-lung model to obtain minute volumes. To assess the improvement by modifying the Rapid-O2, minute volumes were measured using the Rapid-O2. Results: The most appropriate inner catheter was 18 G. The insufflating pressures ranged from 97 (2-mm ID TTC) to 377 cmH2O (16 G) at 15 L/min. During expiration, similar negative pressures of 50 cmH2O were measured in the insufflation catheters at 15 L/min. At lung compliance of 100 ml/cmH2O, the minute volumes through a 2-mm ID and 14 G insufflation catheters were 7.0 and 5.37 L/min, respectively, at 15 L/min. The minute volumes were significantly greater in modified Rapid-O2. Conclusions Modified Rapid-O2 provided sufficient minute volumes in adults using a 14 G or 2-mm ID insufflation catheter at 15 L/min, demonstrating its potential for ventilation in CICO events.

Background: Atherosclerotic cardiovascular disease (ASCVD) is a major health concern, and lipoprotein(a) (Lp(a)) is an independent risk factor. However, there is limited evidence regarding Lp(a) and the risk of ASCVD in Asian populations. This study aimed to assess the predictive value of changes in coronary artery calcification (CAC) for ASCVD risk associated with Lp(a) level. Methods: Participants (n=2,750) were grouped according to their Lp(a) levels, and the association between Lp(a) and CAC progression was examined. CAC progression was defined as the occurrence of incident CAC or a difference ≥2.5 between the square root (√) of baseline and follow-up coronary artery calcium scores (CACSs) (Δ√transformed CACS). To adjust for differences in follow-up periods, Δ√transformed CACS was divided by the follow- up period (in years). Results: Over an average follow-up of 3.07 years, 18.98% of participants experienced CAC progression. Those with disease progression had notably higher Lp(a) levels. Higher Lp(a) tertiles correlated with increased baseline and follow-up CACS, CAC progression (%), and Δ√transformed CACS. Even after adjustment, higher Lp(a) levels were associated with CAC progression. However, annualized Δ√transformed CACS analysis yielded no significant results. Conclusion This study demonstrated an association between elevated Lp(a) levels and CAC progression in a general population without ASCVD. However, longer-term follow-up studies are needed to obtain meaningful results regarding CAC progression. Further research is necessary to utilize Lp(a) level as a predictor of cardiovascular disease and to establish clinically relevant thresholds specific to the Korean population.

Idiopathic nonspecific interstitial pneumonia (iNSIP) is recognized as a distinct entity among various types of idiopathic interstitial pneumonias. It is identified histologically by the nonspecific interstitial pneumonia pattern. A diagnosis of iNSIP is feasible once secondary causes or underlying diseases are ruled out. Usually presenting with respiratory symptoms such as shortness of breath and cough, iNSIP has a subacute or chronic course. It predominantly affects females aged 50 to 60 years who are non-smokers. Key imaging findings on chest high-resolution computed tomography include bilateral reticular opacities in lower lungs, traction bronchiectasis, reduced lung volumes and, ground-glass opacities. Abnormalities are typically diffuse across both lungs with subpleural distributions. Treatment often involves systemic steroids, either alone or in combination with other immunosuppressants, although evidence supporting effectiveness of these treatments is limited. Prognosis is generally more favorable for iNSIP than for idiopathic pulmonary fibrosis, with many studies reporting a 5-year survival rate above 70%. Antifibrotic agents should be considered in a condition, termed progressive pulmonary fibrosis, where pulmonary fibrosis progressively worsens.