Search Results (696)

Background/Objectives: Head and neck squamous cell carcinoma (HNSCC) diagnosis and treatment rely heavily on computed tomography (CT) imaging to evaluate tumor characteristics and lymph node (LN) involvement, crucial for staging, prognosis, and therapy planning. Conventional LN evaluation methods based on morphological criteria such as size, shape, and anatomical location often lack sensitivity for early metastasis detection. This study leverages radiomics to extract quantitative features from CT images, addressing the limitations of subjective assessment and aiming to enhance LN classification accuracy while potentially reducing reliance on invasive histopathology. Methods: We analyzed 234 LNs from 27 HNSCC patients, deriving 120 features per node, resulting in over 25,000 data points classified into reactive, pathologic, and pathologic with extracapsular spread classes. Considering the challenges of high dimensionality and limited dataset size, more than 44,000 experiments systematically optimized machine learning models, feature selection methods, and hyperparameters, including ensemble approaches to strengthen classification robustness. A Pareto front strategy was employed to balance diagnostic accuracy with significant feature reduction. Results: The optimal model, validated via 5-fold cross-validation, achieved a balanced accuracy of 0.90, an area under the curve (AUC) of 0.93, and an F1-score of 0.88 using only five radiomics features. Conclusions: This interpretable approach aligns well with clinical radiology practice, demonstrating strong potential for clinical application in noninvasive LN classification in HNSCC. Full article

Background: The varied shape and size of the sphenoid sinuses result in a highly variable degree of extension, described in different ways in the literature. The aim of the study was to create the authors’ classification of the sphenoid sinus extensions into the sphenoid bone processes. Methods: The study was retrospective, based on the results of head CT scans. The study group comprised 432 children, aged from birth to 18 years. Three types of sphenoid sinus extension into the sphenoid bone processes were proposed. Pneumatization of the lesser wing (type I), of the greater wing (type II), and of the pterygoid process (type III). Three subtypes were defined for each type. Pneumatization of the lesser wing in relation to the optic canal: only above (Ia), only below (Ib), and simultaneously above and below (Ic). Pneumatization of the greater wing in relation to the foramen rotundum: only above (IIa), only below (IIb), and simultaneously above and below (IIc). Pneumatization of the pterygoid process in relation to the pterygoid canal: only laterally (IIIa), only medially (IIIb), and simultaneously laterally and medially (IIIc). Results: Pneumatization of the lesser wings was observed in 19.44%, of the greater wings in 36.11%, and of the pterygoid processes in 25.00 of % children. As a result of the analysis conducted in accordance with the proposed classification, bilateral pneumatization of the lesser wings (type I), greater wings (type II), and pterygoid processes (type III) were found to occur more frequently than unilateral pneumatization. In the case of rare subtypes (Ia, Ic, IIa, Iic, or IIIb), a given subtype was observed to occur more frequently unilaterally. Conclusions: In the conducted analysis, we presented the authors’ classification of sphenoid sinus extensions into the sphenoid bone processes. Full article

Existing methods for diagnosing depression rely heavily on subjective evaluations, whereas electroencephalography (EEG) emerges as a promising approach for objective diagnosis due to its non-invasiveness, low cost, and high temporal resolution. However, current EEG analysis methods are constrained by volume conduction effect and class imbalance, both of which adversely affect classification performance. To address these issues, this paper proposes a multi-stage deep learning model for EEG-based depression classification, integrating a cortical feature extraction strategy (CFE), a feature attention module (FA), a graph convolutional network (GCN), and a focal adversarial domain adaptation module (FADA). Specifically, the CFE strategy reconstructs brain cortical signals using the standardized low-resolution brain electromagnetic tomography (sLORETA) algorithm and extracts both linear and nonlinear features that capture cortical activity variations. The FA module enhances feature representation through a multi-head self-attention mechanism, effectively capturing spatiotemporal relationships across distinct brain regions. Subsequently, the GCN further extracts spatiotemporal EEG features by modeling functional connectivity between brain regions. The FADA module employs Focal Loss and Gradient Reversal Layer (GRL) mechanisms to suppress domain-specific information, alleviate class imbalance, and enhance intra-class sample aggregation. Experimental validation on the publicly available PRED+CT dataset demonstrates that the proposed model achieves a classification accuracy of 85.33%, outperforming current state-of-the-art methods by 2.16%. These results suggest that the proposed model holds strong potential for improving the accuracy and reliability of EEG-based depression classification. Full article

Sheep have been widely used as a model for osteoporosis research. This study aimed to characterise changes in microstructure and composition in lumbar vertebrae L1–L7 and the proximal femur after implementation of a bone loss induction protocol (in this species). A sham control and experimental group (glucocorticoid-treated ovariectomized sheep) were used (n = 6/group), with a study duration up to the 24th postoperative week. Through micro-computed tomography, vertebrae and femoral head trabecular bones from the experimental group presented a consistent decrease in bone volume fraction (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) and an increase in trabecular separation (Tb.Sp) and total porosity (p > 0.05). The mineral density of the femoral heads from the experimental group showed a statistically significant decrease (p ˂ 0.05). The entire histomorphometric analysis of the vertebrae in the experimental group showed an increase in cortical porosity (Ct.Po) and a decrease in cortical thickness (Ct.Th) (p ˂ 0.0001 and p ˂ 0.001, respectively). Vertebrae L6 and L7 were the most affected, showing a significant increase in Ct.Po (p < 0.05) and a significant decrease in Ct.Th at the L6 level (p < 0.05). Regarding the trabecular bone at the vertebral level, only L4 showed a significant increase in Tb.Sp (p ˂ 0.05). In the femoral heads’ subchondral cortical layer, the Ct.Po increased significantly and Ct.Th decreased (p < 0.01), and at the trabecular level, the BV/TV, Tb.Th, and Tb.N decreased significantly, while Tb.Sp increased (p < 0.05). In conclusion, the L4, L6 and L7 vertebrae seem the most suitable for further preclinical and translational studies of vertebral augmentation or spinal fusion in this animal model. Full article

Manual calibration of nuclear medicine scanners currently relies on handling phantoms containing radioactive sources, exposing personnel to high radiation doses and elevating cancer risk. We designed an automated detection framework for robotic inspection on the YOLOv8n foundation. It pairs a lightweight backbone with a shape-aware geometric attention module and an anchor-free head. Facing a small training set, we produced extra images with a GAN and then fine-tuned a pretrained network on these augmented data. Evaluations on a custom dataset consisting of PET/CT gantry and table images showed that the SAM-YOLOv8n model achieved a precision of 93.6% and a recall of 92.8%. These results demonstrate fast, accurate, real-time detection, offering a safer and more efficient alternative to manual calibration of nuclear medicine equipment. Full article

Objectives: Pelvic tumor resections demand high surgical precision to ensure clear margins while preserving function. Although patient-specific instruments (PSIs) improve osteotomy accuracy, positioning errors remain a limitation. This study evaluates the feasibility, accuracy, and usability of a novel dual-function augmented reality (AR) system for intraoperative guidance in PSI positioning and osteotomy execution using a head-mounted display (HMD). The system provides dual-function support by assisting both PSI placement and osteotomy execution. Methods: Ten fresh-frozen cadaveric hemipelves underwent AR-assisted internal hemipelvectomy, using customized 3D-printed PSIs and a new in-house AR software integrated into an HMD. Angular and translational deviations between planned and executed osteotomies were measured using postoperative CT analysis. Absolute angular errors were computed from plane normals; translational deviation was assessed as maximum error at the osteotomy corner point in both sagittal (pitch) and coronal (roll) planes. A Wilcoxon signed-rank test and Bland–Altman plots were used to assess intra-workflow cumulative error. Results: The mean absolute angular deviation was 5.11 ± 1.43°, with 86.66% of osteotomies within acceptable thresholds. Maximum pitch and roll deviations were 4.53 ± 1.32 mm and 2.79 ± 0.72 mm, respectively, with 93.33% and 100% of osteotomies meeting translational accuracy criteria. Wilcoxon analysis showed significantly lower angular error when comparing final executed planes to intermediate AR-displayed planes (p < 0.05), supporting improved PSI positioning accuracy with AR guidance. Surgeons rated the system highly (mean satisfaction ≥ 4.0) for usability and clinical utility. Conclusions: This cadaveric study confirms the feasibility and precision of an HMD-based AR system for PSI-guided pelvic osteotomies. The system demonstrated strong accuracy and high surgeon acceptance, highlighting its potential for clinical adoption in complex oncologic procedures. Full article

China’s southwestern karst landscapes support remarkable cavefish diversity, especially within Sinocyclocheilus, the world’s largest cavefish genus. Using integrative taxonomic methods, we describe Sinocyclocheilus wanlanensis sp. nov., found in a subterranean river in Guizhou Province. This species lacks horn-like cranial structures; its eyes are either reduced to a dark spot or absent. It possesses a pronounced nuchal hump and a forward-protruding, duckbill-shaped head. Morphometric analysis of 28 individuals from six species shows clear separation from related taxa. Nano-CT imaging reveals distinct vertebral and cranial features. Phylogenetic analyses of mitochondrial cytb and ND4 genes place S. wanlanensis within S. angularis group as sister to S. bicornutus, with p-distances of 1.7% (cytb) and 0.7% (ND4), consistent with sister-species patterns within the genus. Sinocyclocheilus wanlanensis is differentiated from S. bicornutus by its eyeless or degenerate-eye condition and lack of bifurcated horns. It differs from S. zhenfengensis, its morphologically closest species, in having degenerate or absent eyes, shorter maxillary barbels, and pelvic fins that reach the anus. The combination of morphological and molecular evidence supports its recognition as a distinct species. Accurate documentation of such endemic and narrowly distributed taxa is important for conservation and for understanding speciation in cave habitats. Full article

The concept of “more is better” has long dominated cancer treatment, emphasizing aggressive therapies despite their toxicity. However, the rise of personalized medicine has fostered treatment de-escalation strategies aimed at minimizing toxicity, improving quality of life, and reducing costs. This position paper highlights key applications of de-escalation in medical oncology, with a primary focus on breast cancer and notable examples in colorectal, head and neck, ovarian, lung, and prostate cancers. Various approaches, including dose reduction, treatment duration shortening, and regimen optimization, have demonstrated efficacy without compromising clinical outcomes. Advances in molecular diagnostics, such as Oncotype Dx in breast cancer and circulating tumor DNA (ctDNA) analysis in colorectal cancer, have facilitated patient selection for de-escalation. While these strategies present promising results, challenges remain, particularly in balancing treatment intensity with oncologic control. The review underscores the need for further prospective trials to refine de-escalation approaches and ensure their safe integration into standard oncologic care. Full article

Background/Objectives: Traumatic brain injury (TBI) is a global public health concern, affecting over 60 million people annually. It is associated with high rates of mortality and disability, particularly among young and economically active individuals, and remains the leading cause of death in people under 40 years of age. Although computed tomography (CT) is the standard method for excluding intracranial bleeding (ICB), it is frequently unavailable in resource-limited settings where the burden of TBI is greatest. The InfraScanner 2000 is a near-infrared spectroscopy (NIRS) device designed to detect ICB and may serve as a triage tool in environments without access to CT imaging. This study aimed to evaluate the diagnostic performance of the InfraScanner 2000 for detecting ICB in the emergency department (ED) of a trauma center in a cohort of Colombian patients with TBI. Methods: This prospective study was conducted in Cali, Colombia, between December 2019 and February 2021. Adult patients presenting to the ED with blunt TBI were enrolled. InfraScanner assessments were performed according to a standardized protocol, and all participants underwent head CT within 6 h of injury. Results: A total of 140 patients were included. Of these, 66% were male and 34% were female. Most patients (63.57%) were between 18 and 39 years old, with a median age of 39 years (IQR: 18–86). The InfraScanner demonstrated a sensitivity of 60.0% (95% CI: 32.5–84.8), specificity of 78.4% (95% CI: 71.2–85.6), positive predictive value (PPV) of 25.0%, and negative predictive value (NPV) of 94.2% for detecting ICB. Conclusions: The InfraScanner 2000 showed good specificity and high NPV in identifying ICB among Colombian patients with TBI. These findings suggest it could serve as a useful triage tool to support decision-making in emergency settings with limited access to CT imaging. Full article

Background/Objectives: Computed tomography (CT) of the head is vital in diagnosing neurological conditions but poses concerns regarding radiation exposure. Traditional diagnostic reference levels (DRLs) are based on anatomical regions, potentially overlooking variations in radiation requirements driven by clinical indication. This study aimed to establish clinical indication-specific DRLs (DRLCIs) for adult head CT to support precision benchmarking and optimise patient safety. Methods: A retrospective observational study was conducted using data from 378 adult patients undergoing non-contrast CT head scans between September 2022 and February 2024. Data on patient demographics, protocols, and radiation dose metrics (Computed Tomography Dose Index Volume and Dose–Length Product) were extracted using DoseWatch™ software. Protocol parameters were standardised across clinical indications such as trauma, stroke, headache, seizure, and infection. Descriptive statistics and correlation analyses were performed. Descriptive statistics, including means, standard deviations, and percentile distributions, were calculated. Correlation analyses were conducted using Pearson’s correlation coefficient to examine relationships between dose metrics and patient variables such as age and body mass index. Results: Mean CTDIvol values ranged from 50.58 mGy (trauma) to 52.90 mGy (infection), while DLP values ranged from 1052.52 to 1219.98 mGy·cm. Percentile distributions were narrow, indicating effective protocol standardisation. The strongest correlation was observed between CTDIvol and DLP (r = 0.89), while age and body mass index showed negligible influence on dose metrics. Comparative analysis showed alignment with international benchmarks from the UK, Qatar, Bahrain, and Nigeria. Conclusions: This study establishes DRLCIs for adult head CT, demonstrating consistent radiation dose delivery across indications with minimal variability. Clinical indication-based benchmarking enhances dose optimisation and aligns with global radiological protection frameworks. Full article

Background/Objectives: This study aimed to prospectively assess the incidence of retinal embolization and to evaluate the vascular and structural changes in the retina and choroid in 52 patients with asymptomatic severe carotid artery disease who underwent carotid artery revascularization. Methods: In our study, 35 patients underwent carotid endarterectomy (CEA) and 17 underwent carotid artery stenting (CAS). Biomicroscopy, fundoscopy, optical coherence tomography (OCT), and OCT-angiography (OCTA) were performed at baseline and 1 month after revascularization. Results: The subfoveal choroidal thickness (SFCT), peripapillary choroidal thickness inferior to the optic nerve head (ppCTi), total overall average retinal vascular density (rVDtot), and total overall average choriocapillaris vascular density (ccVDtot) of the eyes ipsilateral to the operated carotid artery increased significantly after revascularization, whereas a statistically significant increase was also found in the SFCT, rVDtot, and ccVDtot of the contralateral eyes in the overall cohort. Comparing the two study groups, we found that the SFCT, superior and inferior peripapillary choroidal thicknesses (ppCTs, ppCTi), rVDtot, and ccVDtot increased in both groups after revascularization, but significantly only in the CEA group. Furthermore, the temporal choriocapillaris vascular density (ccVDt) increased significantly after revascularization in both groups to a similar degree. Conclusions: Carotid artery revascularization led to a statistically significant increase in retinal and choroidal vascular densities, which indicates significantly improved ocular perfusion. The analysis of the findings of the two study groups suggests the superiority of CEA in terms of improving ocular perfusion in asymptomatic severe carotid artery disease. The rate of retinal embolization was similar in both surgical groups. Full article

Background: Computed Tomography (CT) imaging is widely recognised for its high capability in assessing multiple organs. However, concerns about patient radiation exposure, particularly in children, pose significant challenges. Objective: This study aimed to establish diagnostic reference levels (DRLs) for paediatric patients in the most common CT examinations to monitor and better control radiation doses. Methods: Dosimetry records from 5956 patients’ scans for the four most common CT imaging examinations—Head, Chest, Abdomen Pelvis (AP), and Chest Abdomen Pelvis (CAP)—were considered. The CT dosimetric quantities (CT dose-index volume (CTDI_vol) and dose-length product (DLP)), along with patient demographics (age and weight), were collected from radiology data storage systems. DRLs for CTDI_vol and DLP were determined for each imaging examination, stratified by patient age and weight groups, in accordance with ICRP recommendations. Results: The derived DRLs are presented as [median CTDI_vol (mGy): median DLP (mGy·cm)]. For (<1 yr): Head: 13:187, Chest: 0.4:7, AP: 0.9:19, CAP: 0.4:10. For (1–5 yrs): Head: 16:276, Chest: 1:22, AP: 1.5:58, CAP: 1.6:63. For (6–10 yrs): Head: 19:332, Chest: 1.4:35, AP: 1.9:74, CAP: 2:121. For (11–15 yrs): Head: 21:391, Chest: 3:86, AP: 4.1:191, CAP: 3:165. We observed that both the CTDI_vol and DLP DRL values increase with patient age. Weight-based DRLs follow similar trends for CTDI_vol, while DLP values show noticeable variations in Chest and AP examinations. Conclusions: The study findings highlight the need for review and optimisation of certain scanning protocols, particularly for chest and AP examinations. The derived DRLs are consistent with findings from other studies. The study recommends establishing national paediatric DRLs to enhance radiology practice across the country and ensure adherence to international safety standards. Full article

The elderly population in Japan was 29.3% in 2024, the highest in the world, making medical care for elderly patients an urgent social issue. There are challenges in providing care for elderly patients with head injury, since the buffering effect of the expansion of the subdural space due to brain atrophy masks the neurological symptoms caused by a hematoma, making detection difficult. However, brain damage can be detected with high sensitivity and specificity using blood D-dimer as a biomarker without the need for head computed tomography (CT). Also, about 30% of elderly patients with traumatic brain injury (TBI) are taking antithrombotic drugs, and the effects of these drugs on TBI may include an increase in intracranial hematomas and an increased risk of deterioration. Reversal therapy is used as a countermeasure to prevent hematoma expansion, but this requires the administration of a reversal agent early after injury and before hematoma expansion. In decompression surgery, the use of a mini-craniotomy with neuroendoscopic assistance under local anesthesia can reduce invasiveness, and this method significantly reduces intraoperative bleeding and operation times compared to a major craniotomy. These innovations have improved mortality for TBI in elderly patients, but there is still a need for improvements in functional outcomes. Full article

Background: Older adults are at high risk of falls, and head injuries following these events can have devastating consequences. The In-Patient Post Fall Clinical Pathway is a tool utilised in many hospitals in Queensland, Australia, to guide the need for CT brain imaging post-inpatient fall. This audit aimed to assess the use of CT imaging following inpatient falls in older adults, evaluate adherence to the In-Patient Post Fall Clinical Pathway, and explore factors associated with serious head injury. Methods: A retrospective audit was conducted across two regional Queensland hospitals over 2.5 years. Falls involving patients aged over 65 years were included. Data were analysed using descriptive and bivariate statistical tests. Results: Among 874 eligible falls, the mean patient age was 80.4 years, and approximately two-thirds were male. While 90.6% of patients who had fallen met clinical pathway criteria for a CT head scan, only 50.1% of them received a scan. Serious head injuries were uncommon (2.25% of total falls), with subdural haematoma being most frequent. Only one patient underwent neurosurgical intervention. No missed serious injuries were identified. No individual characteristic was significantly associated with serious head injury, although trends were observed for unwitnessed falls, falls from bed, falls with a head strike, new symptoms four hours post-fall, and anticoagulant use. Conclusions: There is a gap between clinical pathway recommendations and imaging practices, with clinicians often relying on judgement over strict adherence to guidelines. Further research is needed to inform evidence-based and practical decision-making to balance imaging use with clinical risk. Full article

Head and neck squamous cell carcinomas (HNSCCs) that develop from the mucosal epithelium in the oral cavity, pharynx, and larynx are a heterogeneous group of malignant tumors. A lack of appropriate screening and diagnostic methods leads to late diagnoses, with the majority of patients having locally advanced disease, which is associated with a high risk of local recurrence and a poor prognosis and is usually treated with combination therapies. Biomarkers for predicting the therapy response and risk of recurrence in HNSCC patients are urgently needed. Liquid biopsy, e.g., the profiling of circulating biomarkers in bodily fluids, is a promising approach with increasing utility in the early detection and diagnosis of cancer, monitoring cancer progression, patient stratification and treatment selection, detecting minimal residual disease (MRD), and predicting recurrence across different cancer types, including HNSCC. Among liquid biomarkers, circulating tumor DNA (ctDNA), which is based on detecting tumor-specific mutations, insertions/deletions, copy number alterations, and methylation, is the most promising transformative tool in cancer management and personalized cancer treatment. In this review, we provide an update of recent data on the role of non-viral ctDNA in the management of HNSCC patients. Accumulating data suggests the enormous potential of ctDNA profiling by serial sampling during and after definitive therapy in detecting MRD and predicting recurrence in HNSSC patients treated with a single treatment modality (surgery or radiotherapy) or with combination therapies, including immune-checkpoint-inhibitor-based immunotherapy. By incorporating the latest immunotherapy trials and organizing the data by the treatment modality, this review offers a novel perspective not found in previous surveys. Full article