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1.
Ultrasonography ; : 111-120, 2023.
Article in English | WPRIM | ID: wpr-969251

ABSTRACT

Purpose@#Although the taller-than-wide (TTW) sign has been regarded as one of the most specific ultrasound (US) features of thyroid malignancy, uncertainty still exists regarding the US probe’s orientation when evaluating it. This study investigated which US plane would be optimal to identify the TTW sign based on malignancy risk stratification using a registry-based imaging dataset. @*Methods@#A previous study by 17 academic radiologists retrospectively analyzed the US images of 5,601 thyroid nodules (≥1 cm, 1,089 malignant and 4,512 benign) collected in the webbased registry of Thyroid Imaging Network of Korea through the collaboration of 26 centers. The present study assessed the diagnostic performance of the TTW sign itself and fine needle aspiration (FNA) indications via a comparison of four international guidelines, depending on the orientation of the US probe (criterion 1, transverse plane; criterion 2, either transverse or longitudinal plane). @*Results@#Overall, the TTW sign was more frequent in malignant than in benign thyroid nodules (25.3% vs. 4.6%). However, the statistical differences between criteria 1 and 2 were negligible for sensitivity, specificity, and area under the curve (AUC) based on the size effect (all P0.05, respectively). @*Conclusion@#A longitudinal US probe orientation provided little additional diagnostic value over the transverse orientation in detecting the TTW sign of thyroid nodules.

2.
Ultrasonography ; : 275-285, 2023.
Article in English | WPRIM | ID: wpr-969228

ABSTRACT

Purpose@#This study evaluated thyroid cancer risk in a lung cancer screening population according to the presence of an incidental thyroid nodule (ITN) detected on low-dose chest computed tomography (LDCT). @*Methods@#Of 47,837 subjects who underwent LDCT, a lung cancer screening population according to the National Lung Screening Trial results was retrospectively enrolled. The prevalence of ITN on LDCT was calculated, and the ultrasonography (US)/fine-needle aspiration (FNA)–based risk of thyroid cancer according to the presence of ITN on LDCT was compared using the Fisher exact or Student t-test as appropriate. @*Results@#Of the 2,329 subjects (female:male=44:2,285; mean age, 60.9±4.9 years), the prevalence of ITN on LDCT was 4.8% (111/2,329). The incidence of thyroid cancer was 0.8% (18/2,329, papillary thyroid microcarcinomas [PTMCs]) and was higher in the ITN-positive group than in the ITN-negative group (3.6% [4/111] vs. 0.6% [14/2,218], P=0.009). Among the 2,011 subjects who underwent both LDCT and thyroid US, all risks were higher (P<0.001) in the ITNpositive group than in the ITN-negative group: presence of thyroid nodule on US, 94.1% (95/101) vs. 48.6% (928/1,910); recommendation of FNA according to the American Thyroid Association guideline and Korean Thyroid Imaging Reporting and Data System guideline, 41.2% (42/101) vs. 2.4% (46/1,910) and 39.6% (40/101) vs. 1.9% (37/1,910), respectively. @*Conclusion@#Despite a higher risk of thyroid cancer in the LDCT ITN-positive group than in the ITN-negative group in a lung cancer screening population, all cancers were PTMCs. A heavy smoking history may not necessitate thorough screening US for thyroid incidentalomas.

3.
Article in Korean | WPRIM | ID: wpr-969057

ABSTRACT

Background and Objectives@#This study aimed to investigate the protective effect of polydeoxyribonucleotide (PDRN) against skin flap necrosis in a murine skin flap model.Materials and Method Twenty mice with rectangular skin flaps on the dorsum were randomly divided into the PDRN (n=10) and pentobarbital sodium (PBS) (n=10) injection groups. PDRN (8 mg/kg) was subdermally injected at 12 different points immediately after the operation. After 7 days, the flap perfusions were evaluated using a laser speckle contrast imaging (LSCI) system, and specimens were collected for immunohistochemistry analysis. @*Results@#The percentage of survival area relative to the total flap area was significantly higher in the PDRN group (60.87%±7.63%) than in the PBS group (45.23%±10.72%) (p<0.05). The mean LSCI perfusion signal of the distal part of the skin flap in the PBS group was 0.57±0.12, and that in the PDRN group was 0.74±0.13 (p<0.05). The PDRN group had a significantly lower interleukin 1 beta expression than the PBS group and higher vascular endothelial growth factor α expression than the PBS group (p<0.05). @*Conclusion@#These findings suggest that subdermally injected PDRN is more effective in enhancing flap survival during necrosis.

4.
Article in English | WPRIM | ID: wpr-968964

ABSTRACT

Snapping triceps syndrome is a rare disease in which the distal portion of the medial triceps dislocates over the medial epicondyle during flexion of the elbow. It is usually accompanied with ulnar nerve dislocation and double snapping is clinically important feature. Dynamic ultrasonography is useful diagnostic tool for snapping triceps syndrome and ulnar nerve dislocation. But it is often misdiagnosed as ulnar nerve dislocation alone. This review reports a case of 28-year-old professional golfer who had a single snapping on elbow, misdiagnosed as ulnar nerve dislocation alone and eventually diagnosed as ulnar nerve dislocation and snapping triceps syndrome and also reflects factors that are overlooked through first and second operations.

5.
Article in English | WPRIM | ID: wpr-968267

ABSTRACT

Ultrasonography (US) is a primary imaging modality for diagnosing nodular thyroid disease and has an essential role in identifying the most appropriate management strategy for patients with nodular thyroid disease. Standardized imaging techniques and reporting formats for thyroid US are necessary. For this purpose, the Korean Society of Thyroid Radiology (KSThR) organized a task force in June 2021 and developed recommendations for standardized imaging technique and reporting format, based on the 2021 KSThR consensus statement and recommendations for US-based diagnosis and management of thyroid nodules. The goal was to achieve an expert consensus applicable to clinical practice.

6.
Ultrasonography ; : 670-677, 2022.
Article in English | WPRIM | ID: wpr-969208

ABSTRACT

Purpose@#The aim of this multicenter study was to investigate the malignancy risk of minimally cystic thyroid nodules (MCTNs) using cyto-histopathologic diagnoses as the reference standard. @*Methods@#From June 2015 to September 2015, 5,601 thyroid nodules (≥1 cm) from 4,989 consecutive patients who underwent thyroid ultrasonography (US) at 26 institutions were retrospectively analyzed. Each thyroid nodule was categorized according to its cystic proportion: purely solid, minimally cystic (≤10%), and partially cystic (>10%). The malignancy risk of MCTNs was compared with those of purely solid nodules and partially cystic thyroid nodules (PCTNs). The malignancy risk of MCTNs was assessed according to echogenicity and the presence of suspicious US features. @*Results@#The prevalence of MCTNs was 22.5%. The overall malignancy risk of MCTNs was 8.8%, which was significantly lower than that of purely solid nodules (29.5%) (P0.05). MCTNs were associated with a higher risk of malignancy in hypoechoic nodules than in isohyperechoic nodules and in nodules with suspicious US features than in those without suspicious US features (all P<0.001). @*Conclusion@#The malignancy risk of MCTNs was significantly lower than that of purely solid nodules. MCTNs could be categorized as PCTNs rather than as solid nodules to increase the accuracy of the risk stratification system for thyroid nodules.

7.
Health Communication ; (2): 73-80, 2022.
Article in English | WPRIM | ID: wpr-966906

ABSTRACT

Purpose@#: In emergency department(ED), emergency consultation is often omitted or delayed, resulting in an increase of the length of stay for patients. The present study investigated the emergency consultation computerized system designed for prompt and accurate communication can shorten the time for consultation care. In addition, we tried to confirm how users’ satisfaction with communication for emergency consultation changed before and after using the system. @*Methods@#: We divided the period from arrival to exit of the emergency department into 4 stages, and the time taken for each stage was measured. In addition, the present study conducted a satisfaction survey on the convenience and accuracy of communication among users. @*Results@#: After using the computerized system, the median value of time for emergency consultation treatment decreased significantly from 78 minutes to 39 minutes (p<0.001). In terms of communication convenience, more than two-thirds of the users responded positively. @*Conclusion@#: The system that computerized the initial communication shortened the time required for emergency consultation and increased satisfaction in terms of convenience of communication between medical staff.

8.
Article in English | WPRIM | ID: wpr-918229

ABSTRACT

Objective@#This study aimed to explore the myelin volume change in patients with mild traumatic brain injury (mTBI) with post-concussion syndrome (PCS) using a multidynamic multiecho (MDME) sequence and automatic whole-brain segmentation. @*Materials and Methods@#Forty-one consecutive mTBI patients with PCS and 29 controls, who had undergone MRI including the MDME sequence between October 2016 and April 2018, were included. Myelin volume fraction (MVF) maps were derived from the MDME sequence. After three dimensional T1-based brain segmentation, the average MVF was analyzed at the bilateral cerebral white matter (WM), bilateral cerebral gray matter (GM), corpus callosum, and brainstem. The Mann–Whitney U-test was performed to compare MVF and myelin volume between patients with mTBI and controls. Myelin volume was correlated with neuropsychological test scores using the Spearman rank correlation test. @*Results@#The average MVF at the bilateral cerebral WM was lower in mTBI patients with PCS (median [interquartile range], 25.2% [22.6%–26.4%]) than that in controls (26.8% [25.6%–27.8%]) (p = 0.004). The region-of-interest myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (1.87 cm3 [1.70–2.05 cm3 ] vs. 2.21 cm3 [1.86– 3.46 cm3 ]; p = 0.003) and brainstem (9.98 cm3 [9.45–11.00 cm3 ] vs. 11.05 cm3 [10.10–11.53 cm3 ]; p = 0.015). The total myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (0.45 cm3 [0.39–0.48 cm3 ] vs. 0.48 cm3 [0.45–0.54 cm3 ]; p = 0.004) and brainstem (1.45 cm3 [1.28–1.59 cm3 ] vs. 1.54 cm3 [1.42–1.67 cm3 ]; p = 0.042). No significant correlation was observed between myelin volume parameters and neuropsychological test scores, except for the total myelin volume at the bilateral cerebral WM and verbal learning test (delayed recall) (r = 0.425; p = 0.048). @*Conclusion@#MVF quantified from the MDME sequence was decreased at the bilateral cerebral WM in mTBI patients with PCS. The total myelin volumes at the corpus callosum and brainstem were decreased in mTBI patients with PCS due to atrophic changes.

9.
Article in English | WPRIM | ID: wpr-918219

ABSTRACT

Objective@#To compare core needle biopsy (CNB) and repeat fine-needle aspiration (rFNA) to reduce the rate of diagnostic surgery and prevent unnecessary surgery in nodules initially diagnosed as atypia/follicular lesions of undetermined significance (AUS/FLUS). @*Materials and Methods@#This study included 231 consecutive patients (150 female and 81 male; mean age ± standard deviation, 51.9 ± 11.7 years) with 235 thyroid nodules (≥ 1 cm) initially diagnosed as AUS/FLUS, who later underwent both rFNA and CNB. The nodules that required diagnostic surgery after the biopsy were defined using three different scenarios according to the rFNA and CNB results: criterion 1, surgery for low-risk indeterminate (categories I and III); criterion 2, surgery for high-risk indeterminate (categories IV and V); and criterion 3, surgery for all indeterminate nodules (categories I, III, IV, and V). We compared the expected rates of diagnostic surgery between CNB and rFNA in all 235 nodules using the three surgical criteria. In addition, the expected rates of unnecessary surgery (i.e., surgery for benign pathology) were compared in a subgroup of 182 nodules with available final diagnoses. @*Results@#CNB showed significantly lower rates of nondiagnostic, AUS/FLUS, and suspicious for malignancy diagnoses (p ≤ 0.016) and higher rates of follicular neoplasm or suspicious for a follicular neoplasm (p < 0.001) and malignant diagnoses (p = 0.031). CNB showed a significantly lower expected rate of diagnostic surgery than rFNA for criterion 1 (29.8% vs. 48.1%, p < 0.001) and criterion 3 (46.4% vs. 55.3%, p = 0.029), and a significantly higher rate for criterion 2 (16.6% vs. 7.2%, p = 0.001). CNB showed a significantly lower expected rate of unnecessary surgery than rFNA for criterion 1 (18.7% vs. 29.7%, p = 0.024). @*Conclusion@#CNB was superior to rFNA in reducing the rates of potential diagnostic surgery and unnecessary surgery for nodules initially diagnosed as AUS/FLUS in a scenario where nodules with low-risk indeterminate results (categories I and III) would undergo surgery.

10.
Article in English | WPRIM | ID: wpr-939096

ABSTRACT

Background/Aims@#Efficient anti-fibrotic therapies are required for the treatment of liver cirrhosis. Hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) and cyclooxygenase-2 (COX-2) inhibitors have been reported to have anti-fibrotic effects. Here, we investigated whether combined treatment with a statin and a COX-2 inhibitor has synergistic anti-fibrotic effects. @*Methods@#The effects of treatment strategies incorporating both simvastatin and a COX-2 inhibitor, NS-398, were investigated using an immortalized human hepatic stellate cell line (LX-2) and a hepatic fibrosis mouse model developed using thioacetamide (TAA) in drinking water. Cellular proliferation was investigated via 5-bromo-2-deoxyuridine uptake. Pro- and anti-apoptotic factors were investigated through Western blotting and real-time polymerase chain reaction analysis. @*Results@#The evaluation of the anti-proliferative effects on LX-2 cells showed that the observed effects were more pronounced with combination therapy than with single-drug therapy. Moreover, hepatic fibrosis and collagen deposition decreased significantly in TAA-treated mice in response to the combined treatment strategy. The mechanisms underlying the anti-fibrotic effects of the combination therapy were investigated. The effects of the combination therapy were correlated with increased expression levels of extracellular signal-regulated kinase 1/2 signaling molecules, upregulation of the Bax/Bcl-2 signaling pathway, inhibition of the transforming growth factor-β signaling pathway, and inhibition of tissue inhibitor of matrix metalloproteinases 1 and 2. @*Conclusions@#The combination of simvastatin and NS-398 resulted in a synergistic anti-fibrotic effect through multiple pathways. These findings offer a theoretical insight into the possible clinical application of this strategy for the treatment of advanced liver diseases with hepatic fibrosis.

11.
Article in English | WPRIM | ID: wpr-938764

ABSTRACT

Objective@#Preoperative differential diagnosis of follicular-patterned lesions is challenging. This multicenter cohort study investigated the clinicoradiological characteristics relevant to the differential diagnosis of such lesions. @*Materials and Methods@#From June to September 2015, 4787 thyroid nodules (≥ 1.0 cm) with a final diagnosis of benign follicular nodule (BN, n = 4461), follicular adenoma (FA, n = 136), follicular carcinoma (FC, n = 62), or follicular variant of papillary thyroid carcinoma (FVPTC, n = 128) collected from 26 institutions were analyzed. The clinicoradiological characteristics of the lesions were compared among the different histological types using multivariable logistic regression analyses. The relative importance of the characteristics that distinguished histological types was determined using a random forest algorithm. @*Results@#Compared to BN (as the control group), the distinguishing features of follicular-patterned neoplasms (FA, FC, and FVPTC) were patient’s age (odds ratio [OR], 0.969 per 1-year increase), lesion diameter (OR, 1.054 per 1-mm increase), presence of solid composition (OR, 2.255), presence of hypoechogenicity (OR, 2.181), and presence of halo (OR, 1.761) (all p < 0.05). Compared to FA (as the control), FC differed with respect to lesion diameter (OR, 1.040 per 1-mm increase) and rim calcifications (OR, 17.054), while FVPTC differed with respect to patient age (OR, 0.966 per 1-year increase), lesion diameter (OR, 0.975 per 1-mm increase), macrocalcifications (OR, 3.647), and non-smooth margins (OR, 2.538) (all p < 0.05). The five important features for the differential diagnosis of follicular-patterned neoplasms (FA, FC, and FVPTC) from BN are maximal lesion diameter, composition, echogenicity, orientation, and patient’s age. The most important features distinguishing FC and FVPTC from FA are rim calcifications and macrocalcifications, respectively. @*Conclusion@#Although follicular-patterned lesions have overlapping clinical and radiological features, the distinguishing features identified in our large clinical cohort may provide valuable information for preoperative distinction between them and decision-making regarding their management.

12.
Article in Korean | WPRIM | ID: wpr-938362

ABSTRACT

Objective@#Emergency cricothyroidotomy is an infrequently performed procedure and post-procedural complications may result from attempting to pass a device with a large external diameter through the cricothyroid membrane. This study aimed to determine the maximum height of the cricothyroid membrane according to the patient’ s sex and age based on cervical-spine computed tomography (C-spine CT) in the emergency department (ED) and determine the appropriate endotracheal tube (ETT) size. @*Methods@#A retrospective analysis of patients was conducted from May 2014 to April 2020 in the ED. The data were obtained from medical records. Electronic calipers were used to measure the maximum height of the cricothyroid membrane in C-spine CT by an emergency physician and an emergency medicine resident. @*Results@#Six hundred and sixty-four patients were included in the study. The mean height of the cricothyroid membrane was 10.11±2.24 mm in males (n=351) and 8.90±1.84 mm in females (n=313) (P<0.001). In males, the cricothyroid membrane height showed significant variance between the ≥75-year-old and the 25-34-year-old groups (9.26±2.40 mm vs. 11.80±2.36 mm) (P<0.001). The tube size of the cricothyroidotomy equipment was suitable for more than 72.1% of patients when applied with an ETT (internal diameter ≤6.0 mm). @*Conclusion@#This study showed that the height of the cricothyroid membrane differed according to sex and also age in males. It may thus be necessary to consider anatomical differences according to sex and age when selecting the appropriate tube size to reduce complications during emergency cricothyroidotomy.

13.
Article in English | WPRIM | ID: wpr-937429

ABSTRACT

Skeletal muscle is now regarded as an endocrine organ based on its secretion of myokines and exerkines, which, in response to metabolic stimuli, regulate the crosstalk between the skeletal muscle and other metabolic organs in terms of systemic energy homeostasis. This conceptual basis of skeletal muscle as a metabolically active organ has provided insights into the potential role of physical inactivity and conditions altering muscle quality and quantity in the development of multiple metabolic disorders, including insulin resistance, obesity, and diabetes. Therefore, it is important to understand human muscle physiology more deeply in relation to the pathophysiology of metabolic diseases. Since monolayer cell lines or animal models used in conventional research differ from the pathophysiological features of the human body, there is increasing need for more physiologically relevant in vitro models of human skeletal muscle. Here, we introduce recent studies on in vitro models of human skeletal muscle generated from adult myogenic progenitors or pluripotent stem cells and summarize recent progress in the development of three-dimensional (3D) bioartificial muscle, which mimics the physiological complexity of native skeletal muscle tissue in terms of maturation and functionality. We then discuss the future of skeletal muscle 3D-organoid culture technology in the field of metabolic research for studying pathological mechanisms and developing personalized therapeutic strategies.

14.
Yonsei Medical Journal ; : 470-479, 2022.
Article in English | WPRIM | ID: wpr-927165

ABSTRACT

Purpose@#Access block due to the lack of hospital beds causes crowding of emergency departments (ED). We initiated the “boarding restriction protocol” that limits the time of stay in the ED for patients awaiting hospitalization to 24 hours from arrival. The purpose of this study was to determine the effect of the boarding restriction protocol on ED crowding. @*Materials and Methods@#The primary outcome was ED occupancy rate, which was calculated as the ratio of the number of occupying patients to the total number of ED beds. Time factors, such as length of stay (LOS), treatment time, and boarding time, were investigated. @*Results@#The mean of the ED occupancy rate decreased from 1.532±0.432 prior to implementation of the protocol to 1.273±0.353 after (p<0.001). According to time series analysis, the absolute effect caused by the protocol was -0.189 (-0.277 to -0.110) (p=0.001). The proportion of patients with LOS exceeding 24 hours decreased from 7.6% to 4.0% (p<0.001). Among admitted patients, ED LOS decreased from 770.7 (421.4–1587.1) minutes to 630.2 (398.0–1156.8) minutes (p<0.001); treatment time increased from 319.6 (198.5–482.8) minutes to 344.7 (213.4–519.5) minutes (p<0.001); and boarding time decreased from 298.9 (109.5–1149.0) minutes to 204.1 (98.7–545.7) minutes (p<0.001). In pre-protocol period, boarding patients accumulated in the ED during the weekdays and resolved on Friday, but this pattern was alleviated in post-period. @*Conclusion@#The boarding restriction protocol was effective in alleviating ED crowding by reducing the accumulation of boarding patients in the ED during the weekdays

15.
Article in English | WPRIM | ID: wpr-926078

ABSTRACT

Purpose@#Vascular invasion is a well-known independent prognostic factor in colon cancer and tumor sidedness is also being considered a prognostic factor. The aim of this study was to compare the oncological impact of vascular invasion depending on the tumor location in stages I to III colon cancer. @*Methods@#A retrospective analysis was performed using data from patients who underwent curative resection between 2004 and 2015. Patients were divided into right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups according to the tumor location. Disease-free survival (DFS) and overall survival (OS) were compared between the RCC and LCC groups, depending on the presence of vascular invasion. @*Results@#A total of 793 patients were included, of which 304 (38.3%) had RCC and 489 (61.7%) had LCC. DFS and OS did not differ significantly between the RCC and LCC groups. Vascular invasion was a poor prognostic factor for DFS in both RCC (hazard ratio [HR], 2.291; 95% confidence interval [CI], 1.186–4.425; p = 0.010) and LCC (HR, 1.848; 95% CI, 1.139–2.998; p = 0.011). Additionally, it was associated with significantly worse OS in the RCC (HR, 3.503; 95% CI, 1.681–7.300; p < 0.001), but not in the LCC group (HR, 1.676; 95% CI, 0.885–3.175; p = 0.109). Multivariate analysis revealed that vascular invasion was independently poor prognostic factor for OS in the RCC (HR, 3.186; 95% CI, 1.391–7.300; p = 0.006). @*Conclusion@#This study demonstrated that RCC with vascular invasion had worse OS than LCC with vascular invasion.

16.
Article in English | WPRIM | ID: wpr-925526

ABSTRACT

Malignant hyperthermia is an extremely rare, potentially lethal disorder that occurs in susceptible patients who are exposed to triggering agents such as volatile anesthetic gases or depolarizing muscle relaxants. The clinical manifestations of malignant hyperthermia include hypermetabolism, hyperthermia, hypercapnia, and sustained skeletal muscle rigidity, which result in cardiac arrest, brain damage, and death. It is associated with a high morbidity and mortality rate if not recognized immediately and treated appropriately. We report a case of suspected malignant hyperthermia in a young male patient undergoing axillary osmidrosis surgery.

17.
Article in Korean | WPRIM | ID: wpr-895367

ABSTRACT

Purpose@#We aimed to identify the factors associated with the repeated febrile seizures (RFS), defined as recurrent seizures during the same febrile illness. @*Methods@#We reviewed the medical records of children with febrile seizure who visited 4 academic emergency departments from October 2016 through September 2018. Differences were identified in variables regarding clinical and laboratory characteristics between the children with and without RFS. The RFS was the primary outcome. Logistic regression was conducted to identify factors associated with the occurrence of RFS. @*Results@#Among 1,551 children, 922 were included in the study, of whom, 198 (21.5%) underwent RFS. Of the children with RFS, 188 (94.9%) underwent the recurrences within the initial 24 hours. Logistic regression showed focal seizure (adjusted odds ratio, 6.67; 95% confidence interval, 2.37-18.82), venous pH 30 minutes (1.90; 1.30-2.78) as the factors for RFS. @*Conclusion@#In children with febrile seizure, focal seizure, acidosis, and prolonged postictal state may be independent risk factors for RFS. These findings may be informed to healthcare professionals and parents caring for children with febrile seizure.

18.
Korean Journal of Radiology ; : 1579-1586, 2021.
Article in English | WPRIM | ID: wpr-894800

ABSTRACT

Objective@#To evaluate the diagnostic performance of the modified Korean Thyroid Imaging Reporting and Data System (K-TIRADS), and compare it with the 2016 version of K-TIRADS using the Thyroid Imaging Network of Korea. @*Materials and Methods@#Between June and September 2015, 5708 thyroid nodules (≥ 1.0 cm) from 5081 consecutive patients who had undergone thyroid ultrasonography at 26 institutions were retrospectively evaluated. We used a biopsy size threshold of 2 cm for K-TIRADS 3 and 1 cm for K-TIRADS 4 (modified K-TIRADS 1) or 1.5 cm for K-TIRADS 4 (modified K-TIRADS 3). The modified K-TIRADS 2 subcategorized the K-TIRADS 4 into 4A and 4B, and the cutoff sizes for the biopsies were defined as 1 cm for K-TIRADS 4B and 1.5 cm for K-TIRADS 4A. The diagnostic performance and the rate of unnecessary biopsies of the modified K-TIRADS for detecting malignancy were compared with those of the 2016 K-TIRAD, which were stratified by nodule size (with a threshold of 2 cm). @*Results@#A total of 1111 malignant nodules and 4597 benign nodules were included. The sensitivity, specificity, and unnecessary biopsy rate of the benign nodules were 94.9%, 24.4%, and 60.9% for the 2016 K-TIRADS; 91.0%, 39.7%, and 48.6% for the modified K-TIRADS 1; 84.9%, 45.9%, and 43.5% for the modified K-TIRADS 2; and 76.1%, 50.2%, and 40.1% for the modified K-TIRADS 3. For small nodules (1–2 cm), the diagnostic sensitivity of the modified K-TIRADS decreased by 5.2–25.6% and the rate of unnecessary biopsies reduced by 19.2–32.8% compared with those of the 2016 K-TIRADS (p 2 cm), the modified K-TIRADSs maintained a very high sensitivity for detecting malignancy (98%). @*Conclusion@#The modified K-TIRADSs significantly reduced the rate of unnecessary biopsies for small (1–2 cm) nodules while maintaining a very high sensitivity for malignancy for large (> 2 cm) nodules.

19.
Korean Journal of Radiology ; : 1514-1524, 2021.
Article in English | WPRIM | ID: wpr-894795

ABSTRACT

Objective@#To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. @*Materials and Methods@#One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (Ktrans), fractional volume of vascular plasma space (Vp), and fractional volume of extravascular extracellular space (Ve) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the “radiomics risk score” groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. @*Results@#16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). @*Conclusion@#We developed and validated the “radiomics risk score” from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

20.
Article in English | WPRIM | ID: wpr-894763

ABSTRACT

Imaging plays a key role in the diagnosis and characterization of thyroid diseases, and the information provided by imaging studies is essential for management planning. A referral guideline for imaging studies may help physicians make reasonable decisions and minimize the number of unnecessary examinations. The Korean Society of Thyroid Radiology (KSThR) developed imaging guidelines for thyroid nodules and differentiated thyroid cancer using an adaptation process through a collaboration between the National Evidence-based Healthcare Collaborating Agency and the working group of KSThR, which is composed of radiologists specializing in thyroid imaging. When evidence is either insufficient or equivocal, expert opinion may supplement the available evidence for recommending imaging. Therefore, we suggest rating the appropriateness of imaging for specific clinical situations in this guideline.

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