Kilovoltage x-ray units (50-150 kVp) are widely used for skin cancer treatments, necessitating precise dosimetric characterization to ensure accurate dose delivery. This study validates the depth dose data of the VF-80/𝜇XHP (80 kV, 100 W) x-ray system for use in low-kV therapy with a contemporary detector. This research aims to characterize the kilovoltage VF-80/𝜇XHP x-ray unit with open-ended PMMA and stainless-steel applicators of various diameters by utilizing different x-ray energy values. Measurements included machine output reproducibility, applicator leakage and thickness effects, measurement of HVL, reference output dosimetry, and applicator-to-phantom spacing. PDD curves were obtained using various filter/kV and applicator combinations with a PTW 34013 parallel-plate ionization chamber in a solid water phantom and through MC simulations with the TOPAS Monte Carlo code in a water phantom, which were validated against literature data. The study evaluated around 40 x-ray beams. The PDDs were measured in a solid water phantom using a PTW 34013 ionization chamber and calculated with the TOPAS Monte Carlo code. Both the measured and computed percent depth dose data were compared to the BJR 25 supplementary. The agreement between ionization chamber measurements and MC calculations with BJR 25 supplementary was within [1.9%, 1.5%] for 50 kV x-rays and within [0.5%, 0.2%] for 70 kV x-rays. This research provides the dosimetric analysis of a kilovoltage VF-80/μXHP x-ray machine. The primary focus was on using a PTW 34013 ionization chamber to measure the percentage depth dose in a solid water phantom, along with dose calculations performed using the TOPAS Monte Carlo simulation. The findings align well with existing literature, confirming that this x-ray unit is suitable for low-kV x-ray radiotherapy applications.
Clinical translation of advanced MRI techniques can be hindered by the challenges of performing standardized multicentre imaging trials. This work aims to develop and demonstrate an automated tool for monitoring imaging protocol deviations, enabling corrective action to be taken. A Python-based tool, integrated into the imaging repository XNAT, was developed to compare DICOM series with an agreed imaging protocol, highlighting missing series and parameter deviations. This was demonstrated through retrospective analysis of a prospectively acquired dataset from a ten-site whole-body (WB) MRI study of patients with multiple myeloma. The acquired data were compared to the relevant radiological guidelines and to the site-specific imaging protocols agreed for the study. The rate of technical software failure was 0% across 174 examinations from 10 sites. The clinical guidelines were followed in 87.9% of examinations and compliance with the site-specific imaging protocol was greater than 75.0% for all parameters. Common deviations included number of averages for diffusion-weighted imaging (DWI) and repetition time for DWI and Dixon: 85.2%, 81.7%, and 75.1%, respectively. There was a statistically significant correlation between protocol compliance and overall exam radiological image quality. Repository-integrated software is presented for automated monitoring of imaging protocol compliance to support standardization in multicentre studies and clinical translation. This study presents a novel open-source repository-integrated software tool for automatically monitoring compliance with the expected imaging protocol. Standardized acquisition protocols are crucial in multicentre imaging studies and this tool has the potential to enhance research outcomes and support clinical translation.
Kilovoltage x-ray therapy, which includes superficial x-rays and orthovoltage x-rays, is particularly suited for treatments near the skin surface. Radiation dose deposition at depth is typically characterized by percentage depth dose (PDD) curves. However, PDD data are difficult to obtain in kilovoltage x-ray therapy, hence clinics often rely on British Journal of Radiology Supplement 25 (BJR-25) archival data. This study measured PDD for different energies and field sizes on the Xstrahl 300 kilovoltage x-ray therapy unit for comparison with BJR-25 data. We irradiated EBT3 film in water using different energy and field size combinations, then, compared the acquired PDD curves with BJR-25 data. We used 75, 125, and 250 kVp beams, for 10 × 10 cm2 open field, 4 × 4 cm2 closed-ended square applicator, and open-ended circular applicators of 1.5, 2.0, 2.8, and 4.7 cm diameter. PDD for different energies and field sizes on the Xstrahl 300 kilovoltage x-ray therapy unit agreed well with BJR-25 data. The average difference between measured and BJR-25 data was -0.3 ± 1.8%; 85.9% of the individual local differences were within ±3%, 94.8% within ±4%, and 99.5% within ±5%. The PDD curves presented here, together with BJR-25 data, can serve as useful comparison datasets for the commissioning of kilovoltage x-ray machines. Our film-based measurement technique provides high spatial resolution PDD datapoints for a modern kilovoltage x-ray unit, adding to the limited published data in the kilovoltage energy range.
Electrochemical properties of synovial fluid are variable among patients and can lead to implant corrosion, negatively impacting their longevity. The purpose of this study was to explore the relationships between electrochemical properties of synovial fluid of knee osteoarthritic (OA) patients undergoing total knee arthroplasty (TKA) and their clinical and demographic data. Knee OA patients undergoing TKA were enrolled in this study, and samples of their synovial fluid were collected during surgery and immediately injected into a three-electrode electrochemical cell to measure their electrochemical properties, including open circuit potential, polarization resistance, and cathodic current density. Synovial fluid samples from 43 patients were collected (25 females; mean age 69.9 years (SD 7.6); mean BMI 27.6 kg/m2 (SD 5.2)). Clinical evaluation of the patients was conducted preoperatively to assess the disease severity, the inflammation in the knee joint, and patient-reported outcomes. A correlation analysis was performed to study the relationship between the electrochemical parameters of the synovial fluid and demographic and clinical data of the patients. Significant correlations were found between disease severity and both the polarization resistance and the cathodic current density, between WOMAC stiffness scores and polarization resistance, and between KSS knee scores and both open circuit potential and cathodic current density. Finally, patients with a history of oxygen-reducing medical conditions had larger open circuit potential than patients without this kind of medical history. For the first time, correlations between patients' characteristics clinical and an in vivo electrochemical measurement have been obtained. The results showed that patients with more severe disease and more symptoms had less corrosive synovial fluid. Moreover, this study showed lower corrosive properties of synovial fluid in patients with a history of oxygen-reducing medical conditions, highlighting the critical role of oxygen in corrosion.
Spinal anaesthesia for caesarean delivery commonly causes maternal hypotension due to sympathetic blockade and may occasionally progress to profound bradycardia with haemodynamic collapse when venous return is markedly reduced. We report the case of a 34-year-old gravida 3 para 2 woman at 36 weeks of gestation who underwent emergency caesarean delivery under single-shot spinal anaesthesia. Shortly after the onset of the block, she developed significant hypotension, which rapidly progressed to profound hypotension with marked bradycardia, producing a clinical picture consistent with the Bezold-Jarisch reflex (BJR). After stabilisation, transient rhythm irregularity with intermittent ectopy was observed, without sustained tachyarrhythmia or supraventricular tachyarrhythmia. The rhythm disturbance was benign and self-limited. Postoperatively, a 12-lead electrocardiogram demonstrated a previously undiagnosed Wolff-Parkinson-White (WPW) pattern, and cardiology follow-up was arranged. This case highlights (i) the frequency and clinical significance of spinal anaesthesia-induced hypotension during caesarean delivery, (ii) the potential for bradycardic-hypotensive episodes consistent with BJR or vasovagal physiology when venous return is compromised, and (iii) how adrenergic and anticholinergic rescue therapy (ephedrine and atropine), together with physiological stress, may unmask underlying cardiac conduction abnormalities such as WPW. Current obstetric vasopressor guidelines emphasise proactive blood pressure maintenance, typically using a prophylactic phenylephrine infusion initiated immediately after intrathecal injection in combination with crystalloid co-loading, with rescue vasopressors titrated according to maternal haemodynamics. For newly identified WPW, contemporary recommendations support risk stratification, including assessment for intermittent pre-excitation, and consideration of electrophysiological evaluation and catheter ablation when clinically indicated.
The main treatment method for distal femoral fractures is open reduction and internal fixation with a lateral locking plate. However, the literature indicates that the failure rate for this method is high, the healing is slow, and the prognosis is poor. Therefore, this study aimed to solve the problems of high failure rate and poor rehabilitation. Data from 140 patients with AO/OTA type 33 A/33 C fractures (September 2014 to December 2023) were retrospectively analyzed. After excluding 20 cases (loss to follow-up, Gustilo III fractures, polytrauma), 120 patients were categorized into three groups: locking compression plate (LCP) alone, LCP + percutaneous medial column screws (PMCS), and LCP + auxiliary inner locking plate (ALP). An A3 fracture model of the distal femur with medial bone defect was established to explore the maximum stress and maximum displacement. Biomechanical simulations were carried out under axial, torsional, and bending loads. Clinical outcomes, finite element analysis, and biomechanical tests were compared. The LCP + PMCS technique showed better therapeutic effects compared with the other two groups. There were significant differences in fracture healing time (p < 0.001), range of knee joint motion (p < 0.001), and incidence of complications (p = 0.007). The finite element analysis results showed that the maximum stress and displacement of LCP + PMCS made it the optimal method among the three groups. Biomechanical tests confirmed that LCP + PMCS had higher yield load and stiffness. LCP combined with PMCS offers enhanced biomechanical stability, reduced complications, and minimally invasive advantages, making it a promising strategy for distal femoral fractures, particularly in elderly and osteoporotic patients.
The current role of nuclear medicine in the operating room is closely related to the enhancement of the sentinel node (SN) procedure developed more than three decades ago. At that moment, the so-called triple approach (lymphoscintigraphy, gamma probe detection and blue dye) was established as the standard of care for SN biopsy in melanoma and breast cancer. It also marked a first international multidisciplinary learning effort based on skill transfer and outcome evaluation, laying the fundaments to delineate the emerging field of interventional nuclear medicine (iNM) thanks to a similar multimodality approach and multidisciplinary practice. Currently, imaging modalities like SPECT/CT and PET/CT allow to preoperatively generate precision roadmaps for navigation in the operating room. The combination of modern technologies has facilitated iNM incorporation for surgery in more complex anatomical areas. The SN procedure has been expanded to different gynaecological and urological malignancies as well as head and neck and gastrointestinal cancers. Besides iNM for open surgery, it is also possible to guide robot-assisted laparoscopic procedures for both SN biopsy and resection of oligometastases. The increasing development of hybrid tracers for combined radioguidance and fluorescence will reinforce the role of iNM in the future.
To evaluate the diagnostic value of triple-bolus computed tomography urography (TB-CTU) for ureteropelvic junction obstruction (UPJO) in comparison with split-bolus CTU (SB-CTU). In this single-centre retrospective study, patients under clinical suspicion of UPJO referred from the urology clinic for CTU examination from January 1, 2017 to January 31, 2022, were included. CTU examinations were performed with SB or TB protocols. The images were reviewed by 2 radiologists for assessment of arterial and venous renal pelvis enhancement and arteriovenous differentiation. Interobserver agreement on arteriovenous differentiation was calculated. A total of 23 TB-CTU and 70 SB-CTU examinations were included. The Hounsfield unit (HU) values for the renal artery, renal vein, and upper urinary tract were all significantly higher in the TB group. The proportion of high enhancement of arteries and veins was also significantly higher in the TB group (P < .001). Both radiologists evaluated TB-CTU as providing greater arteriovenous differentiation with strong interobserver agreement (κ = 0.77). TB-CTU exhibited superior arteriovenous differentiation in comparison with SB-CTU, with an acceptable radiation dose. For patients with suspicion of UPJO, TB-CTU may be the imaging modality of choice for evaluating anatomical structures for further management.
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Dysphagia is defined as a subjective sensation of difficulty swallowing and can result from oropharyngeal or esophageal etiologies based upon patient symptoms. Dysphagia affects approximately 16% of adults in the general population, with prevalence increasing with age. Esophagogastroduodenuoscopy (EGD) is initially performed to assess for structural abnormalities resulting in esophageal dysphagia. However, if EGD reveals no pathologic abnormalities, high-resolution manometry (HRM) and barium esophagography are performed in order to assess for underlying causes of dysmotility. Esophageal motility disorders (EMDs) are an underrecognized cause of dysphagia and can be characterized by impaired esophageal peristalsis or lower esophageal sphincter dysfunction. High-resolution manometry (HRM) measures key metrics such as integrated relaxation pressure (IRP), which is the deglutitive relaxation across the LES, and metrics of esophageal body peristalsis based on distal contractile integral (DCI) and distal latency (DL). The Chicago Classification version 4 (CCv4.0), published in 2021, provides a standardized classification scheme for differentiating EMDs using metrics from HRM. Additionally, barium esophagography has remained an important adjunctive diagnostic modality, as this may identify strictures, neoplasms, or hiatal hernias, but can also identify major motility disorders such as achalasia and distal esophageal spasm. The combined use of HRM with timed barium esophagram can enhance the diagnostic accuracy of EMDs, particularly when HRM demonstrates inconclusive findings. Therefore, radiologists should be familiar with how imaging findings from barium esophagram integrate with findings noted on HRM. The aim of this review is to highlight the findings of EMDs noted on HRM in conjunction with barium esophagography, thereby illustrating characteristic patterns of primary and secondary EMDs.
Bisphosphonates and teriparatide are used in the management of osteoporosis and reduction of fracture risk. However, their effects on fracture healing have been subject to debate, with concerns that the antiresorptive action of these drugs might impair bone remodelling and delay union. This systematic review and meta-analysis aimed to assess the effects of anti-osteoporotic medication on fracture union, clinical outcomes, complications, and patient-reported outcome measures for acute fractures in adults. We searched MEDLINE (1946 to Sept 24, 2025), Embase (1974 to Sept 26, 2025), Cochrane Library (1946 to Sept 26, 2025), Web of Science (1900 to Sept 26, 2025), and Scopus (2000 to Sept 26, 2025) for randomised controlled trials involving patients aged 18 years or older who had sustained a fracture and had commenced on or were continuing anti-osteoporotic medicine. The included studies compared at least one form of anti-osteoporotic medication with another anti-osteoporotic medication or a placebo. Outcomes that were common to the studies included rates of non-union and delayed union of fractures, complications, overall time to fracture union, and visual analogue pain scores. χ2, τ2, and I2 tests were conducted to evaluate heterogeneity. For I2 values of 50% or more, subgroup analysis was considered; if subgroup analysis was not feasible, random-effects modelling was used. For I2 values less than 50%, fixed-effect modelling was used. Risk ratios (RRs) and mean difference were calculated with 95% CIs. Standardised mean difference was used if there was substantial heterogeneity between outcome measures. This review is registered with PROSPERO (CRD42021230018). We identified 28 trials reporting on 5085 patients (3513 [69·1%] women and 1090 [21·4%] men; sex was not reported for 482 [9·5%] patients) for inclusion in the systematic review, of which 12 trials were suitable for meta-analysis. From pooled meta-analyses, no statistically significant differences were found between groups receiving bisphosphonate versus control for time to union (standardised mean difference 0·39, 95% CI -0·65 to 1·42; Z=0·73; p=0·47), delayed union (RR 1·24, 95% CI 0·82 to 1·89; Z=1·01; p=0·31), or non-union rates (0·71, 0·14 to 3·72; Z=0·40; p=0·69). Pooled analysis showed a significant reduction in time to union with use of teriparatide compared with a control (mean difference -3·03, 95% CI -3·61 to -2·45; Z=10·32; p<0·0001). There were no significant differences between delayed union rates (RR 0·72, 95% CI 0·18 to 2·84; Z=0·48; p=0·63) and Radiological Union Score for Hip scores (mean difference 0·58, 95% CI -0·46 to 1·62; Z=1·10; p=0·27) for patients receiving teriparatide versus control. On the basis of these analyses, bisphosphonate therapy did not appear to affect the time to or rate of fracture healing. Teriparatide does not appear to delay healing and might reduce the time to union for osteoporotic fractures, although further prospective evidence is needed. Heterogeneous reporting and variation in drug agents and doses used limited the comparison of other variables. Standardised reporting in this area is recommended. None.
MRI and CT are routinely performed in patients with Crohn's disease and allow a panoramic view of the abdominal region, permitting to identify intestinal disease, extraintestinal manifestations, and vascular alteration surrounding the bowel wall. Considering that most errors are related to an insufficient distension of the bowel, the requisite for an adequate MRI or CT study of the intestine is the correct bowel distension in order to have the visualization of the entire bowel. For these reasons, CT and MRI are performed after administration of a contrast medium by mouth (MR-enterography; CT-enterography) or by nasojenunal tube (MR-enteroclysis; CT-enteroclysis). The method of administration of the contrast medium affects the degree of distension of the intestinal loops. In particular, not all small bowel loops are equally distended after administration of the contrast agents by mouth, being the ileum usually better distended than the jejunum. This problem could be solved by using MR-enteroclysis and CT-enteroclysis. In these techniques, contrast medium is administered through the nasojejunal tube, and a better small bowel distension is usually obtained. Even if the study of small bowel disease is the most common indication of MR-enterography or MR-enteroclysis and CT-enterography or CT-enteroclysis, these techniques occasionally may be focused on colon examination. Additionally, water enema may be performed at the end of the MR-enterography (hydro-MRI) to reach optimal colon-rectum distension. In this paper, the authors review the techniques of intestinal distension described in the literature, using some CT and MR examples.
To compare radiation dose and image quality of abdominopelvic CT studies performed on dual-energy energy-integrating detector CT (EID-CT) and photo-counting CT (PCCT) for the same patient cohort with clinically aligned protocols. An IRB-approved retrospective cohort study included 49 patients who underwent portal venous phase abdominopelvic CT exams using both dual-energy CT and PCCT scanners within a maximum interval of 3 months. Images reconstructed included virtual monoenergetic images at 50, 60, and 70 keV and mixed images. CTDIvol values were recorded to assess radiation dose. Regions of interest were drawn in the 6 anatomical locations for quantitative analysis. The overall image quality, contrast enhancement, image noise, and presence of artifacts were evaluated using a 5-point Likert scale. No significant differences were observed in image quality scores between PCCT and EID-CT for most comparisons. Calculated contrast-to-noise ratios (CNR) were significantly higher on PCCT except for 70 keV. PCCT demonstrated a significantly lower radiation dose, with an average reduction of 20% ± 15%, up to 51%. For abdominopelvic CT exams with our institutional protocol settings, PCCT has demonstrated a significant reduction in radiation dose while maintaining similar image quality as EID-CT. With clinically aligned protocols for the same cohort of patients, the results provided robust evidence for understanding the benefits of PCCT. It also provided a possible pathway to transit from EID-CT to PCCT in the abdominopelvic imaging.
To preoperatively predict lymphovascular space invasion (LVSI) in early-stage cervical cancer (CC) using multiparametric MRI (mpMRI) radiomics models. This dual-centre study included 196 early-stage CC patients (Centre A: 142, Dec 2020-Apr 2023; Centre B: 54, May-Oct 2023). Centre A was partitioned into training (n = 99) and internal validation (n = 43) cohorts; Centre B served as external validation. Radiomics features were extracted from T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and contrast-enhanced T1-weighted MRI (CE-MRI) sequences. Feature stability was assessed via intraclass correlation and Dice coefficient, with selection through linear correlation and F-tests. Seven radiomics models (single/combined sequences) were built using the top-performing algorithm among 11 machine learning methods. A combination model (CMIC) integrated the optimal mpMRI model's rad-score with clinical factors. Performance was evaluated by ROC, calibration curves, and DCA across all cohorts. The AdaBoost-based mpMRI model (CE-MRI + DWI + T2WI) utilized 12 selected features. It achieved AUCs of 0.953 (95% CI: 0.916-0.989) in training, 0.868 (0.755-0.981) in internal validation, and 0.797 (0.677-0.916) externally. The CMIC model showed comparable performance (training: 0.957; validation: 0.864; external: 0.847), with no significant differences versus the mpMRI model (P > .05 all cohorts). The AdaBoost-driven mpMRI radiomics model effectively predicts LVSI in early-stage CC. Both mpMRI and CMIC models demonstrate robust preoperative predictive capability. This mpMRI radiomics approach using AdaBoost outperforms single-sequence models for LVSI prediction, enabling personalized treatment strategies for early-stage CC.
Prostate cancer is a common malignancy in men. With the advent of multiparametric MRI and the Prostate Imaging-Reporting and Data System (PI-RADS) framework for grading lesions, there have been multiple advancements in the management and treatment of the disease. There are several new advancements in prostate MRI technology that suggest further exciting developments in the field, ranging from novel imaging sequences to the application of machine learning methods and artificial intelligence (AI) across the imaging pipeline. In this review, we aim to provide context on the current advancements in prostate MRI and will discuss the benefits and drawbacks of several new imaging techniques including hybrid multidimensional MRI, low field strength MRI, restriction spectrum imaging, Vascular, Extracellular, and Restricted Diffusion for Cytometry in Tumour (VERDICT) MRI, luminal water imaging, and hyperpolarized C-13 MRI. Additionally, we will introduce several novel AI methods that have been proposed to improve MRI image quality, prostate lesion detection and characterization, as well as touch on the ethical implications of AI in medical imaging of the prostate.
Medical imaging is fundamental to healthcare systems, aiding in the detection of internal abnormalities related to medical conditions beyond their physical symptoms. In low- and middle-income countries (LMICs), limited access to advanced imaging and scarcity of radiologists for image interpretation are evident. Upgrading available resources with artificial intelligence can expand the diagnostic capacity of LMICs to manage the growing prevalence and incidence of infectious diseases such as tuberculosis (TB). Chest X-rays can act as an effective triage tool for TB screening, and multiple models have been reported to improve the number of cases detected in high-burden settings. The case-finding strategies reported in literature have also demonstrated improved diagnostic accuracy and turnaround time post adoption of artificial intelligence (AI) for chest X-ray interpretation. AI assistance can help in identifying radiological involvement of TB, irrespective of their clinical symptoms. Furthermore, cost-effective, integrated workflows can also efficiently support LMICs by facilitating parallel diagnosis and appropriate linkage to care for multiple chest disorders through a unified pathway, thereby broadening the capabilities of chest X-ray based TB screening. By optimizing and strengthening LMIC health systems with AI, further scale-up and implementation can foster a supportive ecosystem for early disease diagnosis and decentralized care delivery.
This study presents a comprehensive comparison of minimally-invasive extracranial neck imaging modalities-Colour Doppler ultrasound (CDUS), CT angiography (CTA), and MR angiography (MRA)-in acute ischaemic stroke (AIS) patients. The aim was to evaluate vessel stenosis, its related parameters, and assess the role of early CTA/MRA in AIS. Categorical and continuous data were compared with Chi-square and independent Sample t-test, respectively. Spearman rank correlation matrix was performed for non-linear CDUS variables. The agreement between various imaging modalities was calculated with kappa (k) coefficient. AIS was most common in males, aged 61-70 years, associated with hypertension and smoking (P-value < .05). Seventy-four plaques were identified in 50 patients, with good agreement between the 3 imaging (k > 0.6). CDUS was limited in evaluating Vertebral Arteries and plaque characterization. CTA/MRA showed higher sensitivity for defining stenosis and plaques, with good-excellent agreement between them (k > 0.6). CTA and MRA identified 40 and 43 vulnerable plaques, respectively. Colour Doppler ultrasound is subjective, comprehensive assessment of anatomic and hemodynamic parameters but lacks sensitivity in identifying vulnerable plaques. CTA/MRA have better sensitivity with good soft tissue differentiation especially in lesser stenosed vessels. Our results support preferred use of MRA/CTA as first-line modalities in time-sensitive scenarios like acute stroke and need to move beyond CDUS-based assessment. These show promise in detecting vulnerable plaque and predicting AIS risk/recurrence; in patient triage, and to guide early intensive treatment. Longitudinal studies are required to assess risk reduction by early advanced imaging.
This study aimed to provide a comprehensive analysis of the increasing demand for PET-CT imaging in England, driven by advancements in technology and updated clinical guidelines. By comparing the 2013 and 2022 guidelines issued by the Royal College of Radiologists, the analysis sought to quantify the gap between actual PET-CT provision and modeled requirements, benchmarked against international comparators, to inform strategic planning for equitable access to advanced imaging. A detailed modeling approach was developed, mapping guideline-based PET-CT scan requirements to disease incidence and stage for major oncological indications (prostate, lymphoma, neuroendocrine tumors, lung, breast, gynecological cancers) and key non-oncological conditions (dementia, cardiovascular disease). Actual scan volumes were extracted from the NHS Diagnostic Imaging Dataset and cross-referenced with provider data. Unmodeled indications were estimated using proportional scaling. Model outputs were validated against PET-CT utilization rates in Finland, adjusted for UK disease incidence. Future demand projections incorporated population growth, demographic shifts, and evolving disease prevalence. For 2021, modeled estimates indicated a substantial shortfall in PET-CT provision for several high-impact indications, notably prostate cancer, dementia, neuroendocrine tumors, and breast cancer, where actual scan volumes were 2-7 times lower than modeled need. Modeled demand for England (361 900 scans/year) exceeded actual provision (239 367 scans/year) by over 50%. Comparative analysis with Finland confirmed that England's PET-CT rates lagged for most indications except lung cancer. Projections suggest continued growth in demand, particularly for dementia and neuroendocrine tumors, with overall PET-CT needs expected to rise sharply by 2040. England's current PET-CT capacity falls significantly short of evidence-based requirements, especially for emerging indications in neurology and oncology. Without strategic investment and expansion, this gap will widen, risking delayed diagnosis and suboptimal care. Enhanced data collection and ongoing validation are critical for responsive service planning. This is the first study to comprehensively model PET-CT demand in England across multiple disease categories using updated clinical guidelines and international benchmarking. It provides a robust, data-driven framework for forecasting imaging needs, supporting national policy and equitable resource allocation.
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Microvascular invasion (MVI) is considered an independent risk factor for early recurrence after curative resection of hepatocellular carcinoma (HCC). The ability to preoperatively predict MVI could lead to personalized treatment options in high-risk patients. To identify radiomic features from CE-CT that correlate with MVI in patients with HCC and evaluate the robustness and reproducibility of radiomic assessment by manual segmentation between readers with different experience. Clinical, CT imaging, and histological parameters were recorded. Sixty-two HCC lesions were manually contoured by three radiologists. Radiomic features were extracted. Features best correlating with angioinvasion were selected and assessed in univariate and multivariate models by means of 100 trials of 5-fold stratified cross-validation in terms of AUC, sensitivity, and specificity. The model identified on contours from the most experienced operator was then tested on contours from the other operators to assess inter-reader reproducibility. Feature selection identified LI-RADS category and four arterial-phase radiomic texture features, with GLCM-ClusterShade and its high-frequency wavelet variant showing the highest predictive value for MVI. A bivariate logistic regression model combining these two features achieved an AUC of 79%, with 78% sensitivity and 64% specificity. The robustness of manual segmentation was strongly dependent on reader experience, and inter-operator reproducibility was suboptimal when the model was applied to contours from less experienced readers. Radiomics analysis may be able to predict MVI in patients with HCC. However, segmentation methods remain a practical challenge affecting reproducibility in radiomic studies. This study, in agreement with the literature, identifies a radiomic model based on two textural features that could correlate with MVI in HCC. Furthermore, it aims to investigate some of the limitations in the application of radiomics in clinical practice, which still restrict it to a research setting, identifying an important limitation in manual segmentation methods. This aspect has not yet been sufficiently investigated in the literature.