Association between repeat imaging and readmission in patients with acute ischemic stroke: a 16-year nationwide population-based study.

OBJECTIVES: This study aims to evaluate such usage patterns and identify factors that may contribute to the need for repeat imaging in acute ischemic stroke patients, and determine the association between repeat imaging and readmission in Taiwan. METHODS: We searched and analyzed data from the Taiwan National Health Insurance Research Database for patients admitted for acute ischemic stroke between 2002 and 2017. Cases where repeat brain imaging during the initial hospital admission occurred and where patients were readmitted within 30 days following discharge were documented. RESULTS: Of a total of 195,016 patients with new onset ischemic stroke, 51,798 (26.6%) underwent repeat imaging during their initial admission. Factors associated with repeat brain imaging included younger age, longer hospital stay, use of rt-PA therapy (odds ratio = 2.10 [95% CI, 1.98-2.22]), more recent year of diagnosis, higher NIHSS score, and admission to a hospital offering a higher level of care. Repeat imaging was also associated with increased risk of ischemic stroke and all types of stroke readmission. CONCLUSIONS: Repeat brain imaging of patients with stroke has increased in recent years, and it is associated with certain factors including age, length of stay, use of rt-PA, hospital level of care, and NIHSS score. It is also associated with increased readmission. ADVANCES IN KNOWLEDGE: Knowledge of the associations of repeat imaging may help clinicians use repeat imaging more carefully and efficaciously.

Automated osteoporosis classification and T-score prediction using hip radiographs via deep learning algorithm.

Background: Despite being the gold standard for diagnosing osteoporosis, dual-energy X-ray absorptiometry (DXA) is an underutilized screening tool for osteoporosis. Objectives: This study proposed and validated a controllable feature layer of a convolutional neural network (CNN) model with a preprocessing image algorithm to classify osteoporosis and predict T-score on the proximal hip region via simple hip radiographs. Design: This was a single-center, retrospective study. Methods: An image dataset of 3460 unilateral hip images from 1730 patients (age ⩾50 years) was retrospectively collected with matched DXA assessment for T-score for the targeted proximal hip regions to train (2473 unilateral hip images from 1430 patients) and test (497 unilateral hip images from 300 patients) the proposed CNN model. All images were processed with a fully automated CNN model, X1AI-Osteo. Results: The proposed screening tool illustrated a better performance (sensitivity: 97.2%; specificity: 95.6%; positive predictive value: 95.7%; negative predictive value: 97.1%; area under the curve: 0.96) than the open-sourced CNN models in predicting osteoporosis. Moreover, when combining variables, including age, body mass index, and sex as features in the training metric, there was high consistency in the T-score on the targeted hip regions between the proposed CNN model and the DXA (r = 0.996, p < 0.001). Conclusion: The proposed CNN model may identify osteoporosis and predict T-scores on the targeted hip regions from simple hip radiographs with high accuracy, highlighting the future application for population-based opportunistic osteoporosis screening with low cost and high adaptability for a broader population at risk. Trial registration: TMU-JIRB N201909036.

Clinical Use of Trabecular Bone Score: The 2023 ISCD Official Positions.

Osteoporosis can currently be diagnosed by applying the WHO classification to bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry (DXA). However, skeletal factors other than BMD contribute to bone strength and fracture risk. Lumbar spine TBS, a grey-level texture measure which is derived from DXA images has been extensively studied, enhances fracture prediction independent of BMD and can be used to adjust fracture probability from FRAX® to improve risk stratification. The purpose of this International Society for Clinical Densitometry task force was to review the existing evidence and develop recommendations to assist clinicians regarding when and how to perform, report and utilize TBS. Our review concluded that TBS is most likely to alter clinical management in patients aged ≥ 40 years who are close to the pharmacologic intervention threshold by FRAX. The TBS value from L1-L4 vertebral levels, without vertebral exclusions, should be used to calculate adjusted FRAX probabilities. L1-L4 vertebral levels can be used in the presence of degenerative changes and lumbar compression fractures. It is recommended not to report TBS if extreme structural or pathological artifacts are present. Monitoring and reporting TBS change is unlikely to be helpful with the current version of the TBS algorithm. The next version of TBS software will include an adjustment based upon directly measured tissue thickness. This is expected to improve performance and address some of the technical factors that affect the current algorithm which may require modifications to these Official Positions as experience is acquired with this new algorithm.

Demands for medical imaging and workforce Size: A nationwide population-based Study, 2000-2020.

PURPOSE: The aim of this study was to investigate associations between workforce and workload among radiologists in Taiwan. MATERIALS AND METHODS: Data for the period 2000-2020 describing the demand for imaging services and radiologists have been obtained from databases and statistical reports of the Ministry of Health and Welfare. The future demand for radiologists was based on Taiwanese people aged 40 and over. RESULTS: The workforce of Taiwan's radiologists has increased by 6 % annually over the past 20 years (from 450 to 993), performing 2125, 3202 and 3620 monthly examinations (mainly conventional radiography and CT) in medical centers, regional hospitals and district hospitals. Between 2000 and 2020, the use of CT and MRI increased by more than 3.5 times. Demand for interventional radiology also increased by 1.77 times, 2.25 times, and 5 times, respectively. To maintain this volume of services in 2040, at least 1168 radiologists are needed, about 1.18 times more in 2020. CONCLUSION: Taiwan has 2.4 to 2.9 times fewer radiologists than the United States and 3 times fewer than Europe, while the annual workload is approximately 2 to 3.4 times greater than that of the United States and 1.4 to 2.5 times greater than that of the United Kingdom. This report may serve as a reference for policy makers who address the challenges of the growing workload among radiologists in countries of similar situations.

Low-dose CT screening among never-smokers with or without a family history of lung cancer in Taiwan: a prospective cohort study.

BACKGROUND: In Taiwan, lung cancers occur predominantly in never-smokers, of whom nearly 60% have stage IV disease at diagnosis. We aimed to assess the efficacy of low-dose CT (LDCT) screening among never-smokers, who had other risk factors for lung cancer. METHODS: The Taiwan Lung Cancer Screening in Never-Smoker Trial (TALENT) was a nationwide, multicentre, prospective cohort study done at 17 tertiary medical centres in Taiwan. Eligible individuals had negative chest radiography, were aged 55-75 years, had never smoked or had smoked fewer than 10 pack-years and stopped smoking for more than 15 years (self-report), and had one of the following risk factors: a family history of lung cancer; passive smoke exposure; a history of pulmonary tuberculosis or chronic obstructive pulmonary disorders; a cooking index of 110 or higher; or cooking without using ventilation. Eligible participants underwent LDCT at baseline, then annually for 2 years, and then every 2 years up to 6 years thereafter, with follow-up assessments at each LDCT scan (ie, total follow-up of 8 years). A positive scan was defined as a solid or part-solid nodule larger than 6 mm in mean diameter or a pure ground-glass nodule larger than 5 mm in mean diameter. Lung cancer was diagnosed through invasive procedures, such as image-guided aspiration or biopsy or surgery. Here, we report the results of 1-year follow-up after LDCT screening at baseline. The primary outcome was lung cancer detection rate. The p value for detection rates was estimated by the χ2 test. Univariate and multivariable logistic regression analyses were used to assess the association between lung cancer incidence and each risk factor. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of LDCT screening were also assessed. This study is registered with ClinicalTrials.gov, NCT02611570, and is ongoing. FINDINGS: Between Dec 1, 2015, and July 31, 2019, 12 011 participants (8868 females) were enrolled, of whom 6009 had a family history of lung cancer. Among 12 011 LDCT scans done at baseline, 2094 (17·4%) were positive. Lung cancer was diagnosed in 318 (2·6%) of 12 011 participants (257 [2·1%] participants had invasive lung cancer and 61 [0·5%] had adenocarcinomas in situ). 317 of 318 participants had adenocarcinoma and 246 (77·4%) of 318 had stage I disease. The prevalence of invasive lung cancer was higher among participants with a family history of lung cancer (161 [2·7%] of 6009 participants) than in those without (96 [1·6%] of 6002 participants). In participants with a family history of lung cancer, the detection rate of invasive lung cancer increased significantly with age, whereas the detection rate of adenocarcinoma in situ remained stable. In multivariable analysis, female sex, a family history of lung cancer, and age older than 60 years were associated with an increased risk of lung cancer and invasive lung cancer; passive smoke exposure, cumulative exposure to cooking, cooking without ventilation, and a previous history of chronic lung diseases were not associated with lung cancer, even after stratification by family history of lung cancer. In participants with a family history of lung cancer, the higher the number of first-degree relatives affected, the higher the risk of lung cancer; participants whose mother or sibling had lung cancer were also at an increased risk. A positive LDCT scan had 92·1% sensitivity, 84·6% specificity, a PPV of 14·0%, and a NPV of 99·7% for lung cancer diagnosis. INTERPRETATION: TALENT had a high invasive lung cancer detection rate at 1 year after baseline LDCT scan. Overdiagnosis could have occurred, especially in participants diagnosed with adenocarcinoma in situ. In individuals who do not smoke, our findings suggest that a family history of lung cancer among first-degree relatives significantly increases the risk of lung cancer as well as the rate of invasive lung cancer with increasing age. Further research on risk factors for lung cancer in this population is needed, particularly for those without a family history of lung cancer. FUNDING: Ministry of Health and Welfare of Taiwan.

Performance measures of 8,169,869 examinations in the National Breast Cancer Screening Program in Taiwan, 2004-2020.

BACKGROUND: The benefits of mammographic screening have been shown to include a decrease in mortality due to breast cancer. Taiwan's Breast Cancer Screening Program is a national screening program that has offered biennial mammographic breast cancer screening for women aged 50-69 years since 2004 and for those aged 45-69 years since 2009, with the implementation of mobile units in 2010. The purpose of this study was to compare the performance results of the program with changes in the previous (2004-2009) and latter (2010-2020) periods. METHODS: A cohort of 3,665,078 women who underwent biennial breast cancer mammography screenings from 2004 to 2020 was conducted, and data were obtained from the Health Promotion Administration, Ministry of Health and Welfare of Taiwan. We compared the participation of screened women and survival rates from breast cancer in the earlier and latter periods across national breast cancer screening programs. RESULTS: Among 3,665,078 women who underwent 8,169,869 examinations in the study population, the screened population increased from 3.9% in 2004 to 40% in 2019. The mean cancer detection rate was 4.76 and 4.08 cancers per 1000 screening mammograms in the earlier (2004-2009) and latter (2010-2020) periods, respectively. The 10-year survival rate increased from 89.68% in the early period to 97.33% in the latter period. The mean recall rate was 9.90% (95% CI: 9.83-9.97%) in the early period and decreased to 8.15% (95%CI, 8.13-8.17%) in the latter period. CONCLUSIONS: The evolution of breast cancer screening in Taiwan has yielded favorable outcomes by increasing the screening population, increasing the 10-year survival rate, and reducing the recall rate through the participation of young women, the implementation of a mobile unit service and quality assurance program, thereby providing historical evidence to policy makers to plan future needs.

Effectiveness of Repetitive Transcranial Magnetic Stimulation Combined With Transspinal Electrical Stimulation on Corticospinal Excitability for Individuals With Incomplete Spinal Cord Injury: A Pilot Study.

Repetitive Transcranial Magnetic Stimulation (rTMS) and transspinal electrical stimulation (tsES) have been proposed as a novel neurostimulation modality for individuals with incomplete spinal cord injury (iSCI). In this study, we integrated magnetic and electrical stimulators to provide neuromodulation therapy to individuals with incomplete spinal cord injury (iSCI). We designed a clinical trial comprising an 8-week treatment period and a 4-week treatment-free observation period. Cortical excitability, clinical features, inertial measurement unit and surface electromyography were assessed every 4 weeks. Twelve individuals with iSCI were recruited and randomly divided into a combined therapy group, a magnetic stimulation group, an electrical stimulation group, or a sham stimulation group. The magnetic and electric stimulations provided in this study were intermittent theta-burst stimulation (iTBS) and 2.5-mA direct current (DC) stimulation, respectively. Combined therapy, which involves iTBS and transspinal DC stimulation (tsDCS), was more effective than was iTBS alone or tsDCS alone in terms of increasing corticospinal excitability. In conclusion, the effectiveness of 8-week combined therapy in increasing corticospinal excitability faded 4 weeks after the cessation of treatment. According to the results, combination of iTBS rTMS and tsDCS treatment was more effective than was iTBS rTMS alone or tsDCS alone in enhancing corticospinal excitability. Although promising, the results of this study must be validated by studies with longer interventions and larger sample sizes.

Prevalence of Low Bone Mass and Osteoporosis in Ireland: the Dual-Energy X-Ray Absorptiometry (DXA) Health Informatics Prediction (HIP) Project.

Osteoporosis is a common disease that has a significant impact on patients, healthcare systems, and society. World Health Organization (WHO) diagnostic criteria for postmenopausal women were established in 1994 to diagnose low bone mass (osteopenia) and osteoporosis using dual-energy X-ray absorptiometry (DXA)-measured bone mineral density (BMD) to help understand the epidemiology of osteoporosis, and identify those at risk for fracture. These criteria may also apply to men ≥50 years, perimenopausal women, and people of different ethnicity. The DXA Health Informatics Prediction (HIP) project is an established convenience cohort of more than 36,000 patients who had a DXA scan to explore the epidemiology of osteoporosis and its management in the Republic of Ireland where the prevalence of osteoporosis remains unknown. In this article we compare the prevalence of a DXA classification low bone mass (T-score < -1.0) and of osteoporosis (T-score ≤ -2.5) among adults aged ≥40 years without major risk factors or fractures, with one or more major risk factors, and with one or more major osteoporotic fractures. A total of 33,344 subjects met our study inclusion criteria, including 28,933 (86.8%) women; 9362 had no fractures or major risk factors, 14,932 had one or more major clinical risk factors, and 9050 had one or more major osteoporotic fractures. The prevalence of low bone mass and osteoporosis increased significantly with age overall. The prevalence of low bone mass and osteoporosis was significantly greater among men and women with major osteoporotic fractures than healthy controls or those with clinical risk factors. Applying our results to the national population census figure of 5,123,536 in 2022 we estimate between 1,039,348 and 1,240,807 men and women aged ≥50 years have low bone mass, whereas between 308,474 and 498,104 have osteoporosis. These data are important for the diagnosis of osteoporosis in clinical practice, and national policy to reduce the illness burden of osteoporosis. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Current Progress of Platelet-Rich Derivatives in Cartilage and Joint Repairs.

In recent years, several types of platelet concentrates have been investigated and applied in many fields, particularly in the musculoskeletal system. Platelet-rich fibrin (PRF) is an autologous biomaterial, a second-generation platelet concentrate containing platelets and growth factors in the form of fibrin membranes prepared from the blood of patients without additives. During tissue regeneration, platelet concentrates contain a higher percentage of leukocytes and a flexible fibrin net as a scaffold to improve cell migration in angiogenic, osteogenic, and antibacterial capacities during tissue regeneration. PRF enables the release of molecules over a longer period, which promotes tissue healing and regeneration. The potential of PRF to simulate the physiology and immunology of wound healing is also due to the high concentrations of released growth factors and anti-inflammatory cytokines that stimulate vessel formation, cell proliferation, and differentiation. These products have been used safely in clinical applications because of their autologous origin and minimally invasive nature. We focused on a narrative review of PRF therapy and its effects on musculoskeletal, oral, and maxillofacial surgeries and dermatology. We explored the components leading to the biological activity and the published preclinical and clinical research that supports its application in musculoskeletal therapy. The research generally supports the use of PRF as an adjuvant for various chronic muscle, cartilage, and tendon injuries. Further clinical trials are needed to prove the benefits of utilizing the potential of PRF.

Lymphoma Spectrum of Image Findings in One Patient.

Lymphoma is a malignancy arising from lymphocytes or lymphoblasts. It affects the lymphoid system and may be expressed in a variety of ways and behave in different fashions. Depending on the organ involved, aggressiveness, and primary or secondary disease, the expression of lymphoma shows polymorphism and sometimes makes it difficult to diagnose from imaging. This article will describe the image findings of lymphoma in different organ systems of one patient.

T-score discordance between hip and lumbar spine: risk factors and clinical implications.

Background: T-score discordance is common in osteoporosis diagnosis and leads to problems for clinicians formulating treatment plans. Objectives: This study investigated the potential predictors of T-score discordance and compared fracture risk among individuals with varying T-score discordance status. Design: This was a single-center cross-sectional study conducted at Wan Fang Hospital, Taipei City, between 1 February 2020 and 31 January 2022. Methods: The present study enrolled patients aged ⩾50 years who received advanced bone health examination. Participants with a history of fracture surgery or underlying musculoskeletal diseases were excluded. Bioelectrical impedance analysis and dual-energy X-ray absorptiometry were used to determine the body composition and T-score, respectively. Discordance was defined as different T-score categories between the lumbar spine and hip. The impact of discordance on an individual's fracture risk was assessed using the Fracture Risk Assessment Tool (FRAX). Results: This study enrolled 1402 participants (181 men and 1221 women). Of the 912 participants diagnosed with osteoporosis, 47 (5%) and 364 (40%) were categorized as having major and minor discordance, respectively. Multinomial logistic regression revealed that decreased walking speed was significantly correlated with major discordance but not osteoporosis in both the hip and lumbar spine (odds ratio of 0.25, p = 0.04). The adjusted FRAX scores for the major osteoporotic fracture risks of the major and minor discordance groups were approximately 14%, which was significantly lower than that of people having osteoporosis in both the hip and lumbar spine. Conclusions: Walking speed exhibited the most significant correlation with major discordance in patients with osteoporosis. Although adjusted major fracture risks were similar between the major and minor discordance groups, further longitudinal studies are warranted to confirm this finding. Registrations: This study was approved by the Ethics Committee of Taipei Medical University on 01/04/2022 (TMU-JIRB N202203088).

Automatic Calcification Morphology and Distribution Classification for Breast Mammograms With Multi-Task Graph Convolutional Neural Network.

The morphology and distribution of microcalcifications are the most important descriptors for radiologists to diagnose breast cancer based on mammograms. However, it is very challenging and time-consuming for radiologists to characterize these descriptors manually, and there also lacks of effective and automatic solutions for this problem. We observed that the distribution and morphology descriptors are determined by the radiologists based on the spatial and visual relationships among calcifications. Thus, we hypothesize that this information can be effectively modelled by learning a relationship-aware representation using graph convolutional networks (GCNs). In this study, we propose a multi-task deep GCN method for automatic characterization of both the morphology and distribution of microcalcifications in mammograms. Our proposed method transforms morphology and distribution characterization into node and graph classification problem and learns the representations concurrently. We trained and validated the proposed method in an in-house dataset and public DDSM dataset with 195 and 583 cases,respectively. The proposed method reaches good and stable results with distribution AUC at 0.812 ± 0.043 and 0.873 ± 0.019, morphology AUC at 0.663 ± 0.016 and 0.700 ± 0.044 for both in-house and public datasets. In both datasets, our proposed method demonstrates statistically significant improvements compared to the baseline models. The performance improvements brought by our proposed multi-task mechanism can be attributed to the association between the distribution and morphology of calcifications in mammograms, which is interpretable using graphical visualizations and consistent with the definitions of descriptors in the standard BI-RADS guideline. In short, we explore, for the first time, the application of GCNs in microcalcification characterization that suggests the potential of using graph learning for more robust understanding of medical images.

Natural history and survival rate of familial amyloidosis with polyneuropathy: A nationwide databank.

OBJECTIVE: Hereditary amyloid transthyretin (ATTRv) amyloidosis with polyneuropathy, a rare autosomal-dominant disease, has gained attention in recent years owing to treatment improvements. However, epidemiological real-world mega database of nationwide natural history and survival rates, especially with the specific mutation of Ala97Ser, are limited. METHODS: Taiwan National Health Insurance Research Database contains data from over 23 million individuals; Among them, 175 ATTRv amyloidosis patients validated by rare disease registry were enrolled. Multivariable Cox proportional hazard analyses were applied to investigate the association between baseline characteristics and all-cause mortality. FINDINGS: From 2008 to 2020, the annual incidence and prevalence rates of specific mutations (Ala97Ser) leading to ATTRv amyloidosis with polyneuropathy were 0.04-1.14 and 0.04-4.79 per million in Taiwan, respectively. In Taiwan, these patients exhibited male predominance with a mean age at validation of 62.75 years. At the 5th year after validation, patients exhibited a survival rate of approximately 50%, with higher mortality in male patients (hazard ratio [HR]: 2.22, 95% confidence interval [CI]: 1.15-4.31) and patients older at validation (HR: 1.10, 95% CI: 1.06-1.15). The two most common departments in outpatient were neurology and family medicine, and neurology and cardiology in inpatient. The three most common causes of death registered were unspecified amyloidosis (30.6%), organ-limited amyloidosis (20.9%), and neuropathic heredofamilial amyloidosis (9.7%). INTERPRETATION: The annual prevalence rate of specific mutation (Ala97Ser)-dominant ATTRv amyloidosis with polyneuropathy in Taiwan is comparable to the mid- to high-prevalence country level of the research by Schmidt et al. The extraordinarily high mortality, especially among patients older at validation, may reflect the inadequate awareness and the necessity of early intervention with novel disease-modifying regimens.

Utilization of CT and MRI scanning in Taiwan, 2000-2017.

OBJECTIVES: This population-based study aimed to collect, analyze, and summarize the long-term trends in medical imaging use in Taiwan. METHODS: A retrospective cohort population-based study of medical imaging usage for the individuals who received care under the National Health Insurance system from 2000 to 2017. CT and MRI utilization rates were determined overall as well as across certain variables including patient age, hospital type, health care type, hospital characteristics, and geographic area. RESULTS: Individuals registered in our health insurance system have received 21,766,745 CT scans and 7,520,088 MRI scans from 2000 to 2017. Annual growth rates for both imaging types were positive over that period, though growth rates have slowed in recent years. The growth rate for CT use was greatest (9-12%) between 2001 and 2004, dropped to 2% in 2005, then generally rose thereafter, reaching 3% in 2017. Similarly, MRI use growth peaked at 24% between 2001 and 2003, dropped to 4% in 2005, then increased in a fluctuating manner, reaching 2% in 2017. CONCLUSION: Over the past 2 decades, CT and MRI use in Taiwan has increased sharply, especially in the oldest age group (≥ 60 years old), but growth rates have slowed in recent years. Increases in imaging use have corresponded with improved clinical outcomes, including greater life expectancy and reduced mortality rates, though further assessment is required to demonstrate a direct link with imaging. Nevertheless, the better clinical outcomes are also predisposed by the comprehensive care covered by the NHI system.

Asia-pacific consensus on osteoporotic fracture prevention in postmenopausal women with low bone mass or osteoporosis but no fragility fractures.

Postmenopausal women are at significant risk for osteoporotic fractures due to their rapid bone loss. Half of all postmenopausal women will get an osteoporosis-related fracture over their lifetime, with 25% developing a spine deformity and 15% developing a hip fracture. By 2050, more than half of all osteoporotic fractures will occur in Asia, with postmenopausal women being the most susceptible. Early management can halt or even reverse the progression of osteoporosis. Consequently, on October 31, 2020, the Taiwanese Osteoporosis Association hosted the Asia-Pacific (AP) Postmenopausal Osteoporotic Fracture Prevention (POFP) consensus meeting, which was supported by the Asian Federation of Osteoporosis Societies (AFOS) and the Asia Pacific Osteoporosis Foundation (APOF). International and domestic experts developed ten applicable statements for the prevention of osteoporotic fractures in postmenopausal women with low bone mass or osteoporosis but no fragility fractures in the AP region. The experts advocated, for example, that postmenopausal women with a high fracture risk be reimbursed for pharmaceutical therapy to prevent osteoporotic fractures. More clinical experience and data are required to modify intervention tactics.

Clinical practice guidelines for the prevention and treatment of osteoporosis in Taiwan: 2022 update.

Osteoporosis greatly increases the risk of fractures. Osteoporotic fractures negatively impact quality of life, increase the burden of care, and increase mortality. Taiwan is an area with a high prevalence of osteoporosis. This updated summary of guidelines has been developed by experts of the Taiwan Osteoporosis Association with the intention of reducing the risks of osteoporotic fractures and improving the quality of care for patients with osteoporosis. The updated guidelines compile the latest evidence to provide clinicians and other healthcare professionals with practical recommendations for the prevention, diagnosis, and management of osteoporosis under clinical settings in Taiwan.

Radiologist burnout: Trends in medical imaging utilization under the national health insurance system with the universal code bundling strategy in an academic tertiary medical centre.

PURPOSE: The utilization of diagnostic medical imaging has been growing worldwide. However, no study has investigated the trend in image utilization and the corresponding workload of radiologists under the National Healthcare Insurance (NHI) system with a code-bundling-based reimbursement strategy. We will analyse the trend in diagnostic imaging utilization and the corresponding workload of the radiologists at a single tertiary medical centre using the NHI system. MATERIALS AND METHODS: This was a retrospective study recruiting the diagnostic medical images, including X-rays, CT, and MR performed between 2005 and 2020 at a single medical centre. We investigated the change over time in image utilization and workload for interpreting the images. The two-sided Mann-Kendall test was used for the monotonic trend analysis and Sen's slope estimate was calculated for the annual mean change with the 95% confidence interval (CI). A P value < 0.05 was considered significant. RESULTS: A total of 10,069,583 examinations were performed at our institute from 2005 to 2020, including 7,821,880 X-rays, 1,665,787 CT, and 581,916 MR examinations. The numbers of examinations of X-rays, CT, and MR increased with average annual changes of 13,411.3 (95% CI = 11,875.0-14,773.8), 9,496.7 (95% CI = 8,845.3-9,828.7), and 2,417.1 (95% CI = 2,209.8-2,668.9) respectively, all P < 0.001. The proportion of cases including multiple examinations increased, growing from 21.5% (6,627 in 30,878 cases) to 43.8% (39,417 in 90,032 cases) for CT and from 8.9% (1,316 in 14,791 cases) to 15.7% (6,083 in 38,865 cases) for MR. The average time spent on interpreting each diagnostic image decreased significantly from 16.0 to 2.9 sec. (P < 0.001). CONCLUSION: Imaging utilization increased significantly under the NHI system at a medical centre. The corresponding demand for image interpretation also placed a significant workload on radiologists, potentially contributing to radiologist burnout.