Purpose: 11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results. Methods: This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated. Results: This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%. Conclusion Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.

Purpose: 11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results. Methods: This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated. Results: This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%. Conclusion Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.

Purpose: 11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results. Methods: This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated. Results: This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%. Conclusion Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.

Purpose: 11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results. Methods: This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated. Results: This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%. Conclusion Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.

Purpose: 11C-Methionine PET/CT is a promising method for detecting parathyroid lesions in patients with primary hyperparathyroidism (PHPT). We aimed to determine the diagnostic ability and correlation of digital 11C-Methionine PET/CT for parathyroid lesions in patients with PHPT, particularly in cases where standard imaging methods yielded inconclusive results. Methods: This retrospective analysis was conducted on patients diagnosed with PHPT who underwent digital 11C-Methionine PET/CT imaging because of ambiguous results on standard imaging work-up ( 99m Tc-MIBI parathyroid scan and/or neck ultrasonography). Quantitative 11C-Methionine PET/CT parameters, including maximum standardized uptake value (SUVmax), mean SUV (SUVmean), peak SUV (SUVpeak), parathyroid methionine volume (PMV), and whole methionine uptake(WMU: PMV multiplied by SUVmean) were calculated with various thresholds, and their correlations with biochemical andpathologic parameters were investigated. Results: This study included 22 consecutive patients (10 men and 12 women) with a median age of 64.0 years. The lesion detection rate and sensitivity of digital 11C-Methionine PET/CT were 81.8% (18/22) and 100.0% (18/18), respectively.Quantitative analysis revealed that serum PTH (r = 0.490, P = 0.039) and serum calcium (r = 0.583, P = 0.011) were signifi-cantly correlated with PMV50%. Conclusion Digital 11C-Methionine PET/CT offers good performance in the detection of parathyroid lesions in PHPT patients with inconclusive standard imaging work-up. The volume parameter of PMV50% significantly correlated biochemi-cal parameters and can serve as a complementary diagnostic tool.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Purpose: Radiographic examinations are frequently performed for diagnostic and therapeutic purposes in neonatal intensive care units (NICUs). However, concerns are emerging regarding the safety of radiation exposure, especially in vulnerable preterm infants in periods of rapid cellular division. This quality improvement (QI) project aimed to reduce radiation hazards in level-IV NICU. Methods: We established an "X-ray prescription protocol" and educated the physicians to ensure that only essential radiographs were obtained. Additionally, we discouraged full-body infantograms and emphasized the prescription of targeted radiographs, such as chest or abdominal radiographs. Furthermore, to reduce the dose-area product (DAP, Gy·cm2) values, which act as a surrogate for radiation exposure, we provided training to radiologic technologists on meticulous collimation for each radiography session. We aimed to achieve a 30% reduction in the average monthly cumulative DAP per patient, which was calculated by dividing the total monthly DAP from radiographs in the NICU by the monthly average of patient admissions. Retrospective baseline data were collected 8 months pre-intervention and prospectively for 4 months post-interventions. Results: The average monthly X-ray count per patient was 28.3 in the pre-intervention period (October 2022 to May 2023), which decreased to 25.4 in the post-intervention period (June 2023 to September 2023), reflecting a 10.2% reduction (p=0.109). The average monthly infantogram count per patient showed an 18.0% reduction (25.9% to 21.2%, p=0.016), and the proportion of infantograms in the total X-ray counts decreased from 91.5% to 83.3% (p=0.017). The DAP value per X-ray decreased by 42.6%, from an average of 0.25 to 0.14 (p=0.011). The primary outcome, the average monthly cumulative DAP value per patient, showed a substantial reduction of 48.6%, dropping from 7.00 to 3.60 (p=0.004). The baseline characteristics and short-term morbidities of the patients did not differ significantly between the pre- and post-intervention period. Conclusion Our QI approach, which included discouraging excessive prescriptions of infantograms and promoting optimal collimation, significantly reduced the average monthly radiation exposure in the NICU, benefiting both patients and healthcare workers.

Background/Aims: In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) established clinical predictors for choledocholithiasis. Our study was designed to evaluate these predictors within the Korean clinical context, establish cutoff values, and develop a predictive model. Methods: This retrospective study analyzed patients who underwent laparoscopic cholecystectomy. The relationships between choledocholithiasis and predictors including age, blood tests, and imaging findings were assessed through univariate and multivariate logistic regression analyses. We established Korean cutoff values for these predictors and developed a scoring system for choledocholithiasis using a multivariate logistic regression. The performance of this scoring system was then compared with that of the 2019 ASGE guidelines through a receiver operating characteristic curve. Results: We established Korean cutoff values for age (>70 years), alanine aminotransferase (>26.5 U/L), aspartate aminotransferase (>28.5 U/L), gamma-glutamyl transferase (GGT; >82.5 U/L), alkaline phosphatase (ALP; >77.5 U/L), and total bilirubin (>0.95 mg/dL). In the multivariate analysis, only age >70 years, GGT >77.5 U/L, ALP >77.5 U/L, and common bile duct dilatation remained significant. We then developed a new Korean risk stratification model from the multivariate analysis, with an area under the curve of 0.777 (95% confidence interval, 0.75 to 0.81).Our model was stratified into the low-risk, intermediate-risk, and high-risk groups with the scores being <1.0, 1.0–5.5, and >5.5, respectively. Conclusions Predictors of choledocholithiasis in cholecystectomy patients and their cutoff values in Korean should be adjusted and further studies are needed to develop appropriate guidelines.

Purpose: Radiographic examinations are frequently performed for diagnostic and therapeutic purposes in neonatal intensive care units (NICUs). However, concerns are emerging regarding the safety of radiation exposure, especially in vulnerable preterm infants in periods of rapid cellular division. This quality improvement (QI) project aimed to reduce radiation hazards in level-IV NICU. Methods: We established an "X-ray prescription protocol" and educated the physicians to ensure that only essential radiographs were obtained. Additionally, we discouraged full-body infantograms and emphasized the prescription of targeted radiographs, such as chest or abdominal radiographs. Furthermore, to reduce the dose-area product (DAP, Gy·cm2) values, which act as a surrogate for radiation exposure, we provided training to radiologic technologists on meticulous collimation for each radiography session. We aimed to achieve a 30% reduction in the average monthly cumulative DAP per patient, which was calculated by dividing the total monthly DAP from radiographs in the NICU by the monthly average of patient admissions. Retrospective baseline data were collected 8 months pre-intervention and prospectively for 4 months post-interventions. Results: The average monthly X-ray count per patient was 28.3 in the pre-intervention period (October 2022 to May 2023), which decreased to 25.4 in the post-intervention period (June 2023 to September 2023), reflecting a 10.2% reduction (p=0.109). The average monthly infantogram count per patient showed an 18.0% reduction (25.9% to 21.2%, p=0.016), and the proportion of infantograms in the total X-ray counts decreased from 91.5% to 83.3% (p=0.017). The DAP value per X-ray decreased by 42.6%, from an average of 0.25 to 0.14 (p=0.011). The primary outcome, the average monthly cumulative DAP value per patient, showed a substantial reduction of 48.6%, dropping from 7.00 to 3.60 (p=0.004). The baseline characteristics and short-term morbidities of the patients did not differ significantly between the pre- and post-intervention period. Conclusion Our QI approach, which included discouraging excessive prescriptions of infantograms and promoting optimal collimation, significantly reduced the average monthly radiation exposure in the NICU, benefiting both patients and healthcare workers.

Purpose: Radiographic examinations are frequently performed for diagnostic and therapeutic purposes in neonatal intensive care units (NICUs). However, concerns are emerging regarding the safety of radiation exposure, especially in vulnerable preterm infants in periods of rapid cellular division. This quality improvement (QI) project aimed to reduce radiation hazards in level-IV NICU. Methods: We established an "X-ray prescription protocol" and educated the physicians to ensure that only essential radiographs were obtained. Additionally, we discouraged full-body infantograms and emphasized the prescription of targeted radiographs, such as chest or abdominal radiographs. Furthermore, to reduce the dose-area product (DAP, Gy·cm2) values, which act as a surrogate for radiation exposure, we provided training to radiologic technologists on meticulous collimation for each radiography session. We aimed to achieve a 30% reduction in the average monthly cumulative DAP per patient, which was calculated by dividing the total monthly DAP from radiographs in the NICU by the monthly average of patient admissions. Retrospective baseline data were collected 8 months pre-intervention and prospectively for 4 months post-interventions. Results: The average monthly X-ray count per patient was 28.3 in the pre-intervention period (October 2022 to May 2023), which decreased to 25.4 in the post-intervention period (June 2023 to September 2023), reflecting a 10.2% reduction (p=0.109). The average monthly infantogram count per patient showed an 18.0% reduction (25.9% to 21.2%, p=0.016), and the proportion of infantograms in the total X-ray counts decreased from 91.5% to 83.3% (p=0.017). The DAP value per X-ray decreased by 42.6%, from an average of 0.25 to 0.14 (p=0.011). The primary outcome, the average monthly cumulative DAP value per patient, showed a substantial reduction of 48.6%, dropping from 7.00 to 3.60 (p=0.004). The baseline characteristics and short-term morbidities of the patients did not differ significantly between the pre- and post-intervention period. Conclusion Our QI approach, which included discouraging excessive prescriptions of infantograms and promoting optimal collimation, significantly reduced the average monthly radiation exposure in the NICU, benefiting both patients and healthcare workers.