The volume of in vivo human brains is determined with various MRI measurement tools that have not been assessed against a gold standard. The purpose of this study was to validate the MRI brain volumes by scanning ex vivo, in situ specimens, which allows the extraction of the brain after the scan to compare its volume with the gold-standard water displacement method (WDM). The 3T MRI T₂-weighted, T₁-weighted, and MP2RAGE images of seven anatomical heads fixed with an alcohol-formaldehyde solution were acquired. The gray and white matter were assessed using two methods: (i) a manual intensity-based threshold segmentation using Display (MINC-ToolKit) and (ii) an automatic deep learning-based segmentation tool (SynthSeg). The brains were extracted and their volumes measured with the WDM after the removal of their meninges and a midsagittal cut. Volumes from all methods were compared with the ground truth (WDM volumes) using a repeated-measures analysis of variance. Mean brain volumes, in cubic centimeters, were 1111.14 ± 121.78 for WDM, 1020.29 ± 70.01 for manual T₂-weighted, 1056.29 ± 90.54 for automatic T₂-weighted, 1094.69 ± 100.51 for automatic T₁-weighted, 1066.56 ± 96.52 for automatic magnetization-prepared 2 rapid gradient-echo first inversion time, and 1156.18 ± 121.87 for automatic magnetization-prepared 2 rapid gradient-echo second inversion time. All volumetry methods were significantly different (F = 17.874; p < 0.001) from the WDM volumes, except the automatic T₁-weighted volumes. SynthSeg accurately determined the brain volume in ex vivo, in situ T₁-weighted MRI scans. The results suggested that given the contrast similarity between the ex vivo and in vivo sequences, the brain volumes of clinical studies are most probably sufficiently accurate, with some degree of underestimation depending on the sequence used.

Alzheimer's disease (AD) poses a significant global health challenge, necessitating early and accurate diagnosis to enable timely intervention. Structural MRI (sMRI) is a key imaging modality for detecting AD-related brain atrophy, yet traditional deep learning models like convolutional neural networks (CNNs) struggle to capture complex spatial dependencies critical for AD diagnosis. This study introduces the Regional Attention-Enhanced Vision Transformer (RAE-ViT), a novel framework designed for AD classification using sMRI data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset. RAE-ViT leverages regional attention mechanisms to prioritize disease-critical brain regions, such as the hippocampus and ventricles, while integrating hierarchical self-attention and multi-scale feature extraction to model both localized and global structural patterns. Evaluated on 1152 sMRI scans (255 AD, 521 MCI, 376 NC), RAE-ViT achieved state-of-the-art performance with 94.2 % accuracy, 91.8 % sensitivity, 95.7 % specificity, and an AUC of 0.96, surpassing standard ViTs (89.5 %) and CNN-based models (e.g., ResNet-50: 87.8 %). The model's interpretable attention maps align closely with clinical biomarkers (Dice: 0.89 hippocampus, 0.85 ventricles), enhancing diagnostic reliability. Robustness to scanner variability (92.5 % accuracy on 1.5T scans) and noise (92.5 % accuracy under 10 % Gaussian noise) further supports its clinical applicability. A preliminary multimodal extension integrating sMRI and PET data improved accuracy to 95.8 %. Future work will focus on optimizing RAE-ViT for edge devices, incorporating multimodal data (e.g., PET, fMRI, genetic), and exploring self-supervised and federated learning to enhance generalizability and privacy. RAE-ViT represents a significant advancement in AI-driven AD diagnosis, offering potential for early detection and improved patient outcomes.

Alzheimer's disease is a progressive, neurodegenerative disorder that causes memory loss and cognitive decline. While there has been extensive research in applying deep learning models to Alzheimer's prediction tasks, these models remain limited by lack of available labeled data, poor generalization across datasets, and inflexibility to varying numbers of input scans and time intervals between scans. In this study, we adapt three state-of-the-art temporal self-supervised learning (SSL) approaches for 3D brain MRI analysis, and add novel extensions designed to handle variable-length inputs and learn robust spatial features. We aggregate four publicly available datasets comprising 3,161 patients for pre-training, and show the performance of our model across multiple Alzheimer's prediction tasks including diagnosis classification, conversion detection, and future conversion prediction. Importantly, our SSL model implemented with temporal order prediction and contrastive learning outperforms supervised learning on six out of seven downstream tasks. It demonstrates adaptability and generalizability across tasks and number of input images with varying time intervals, highlighting its capacity for robust performance across clinical applications. We release our code and model publicly at https://github.com/emilykaczmarek/SSL-AD.

Overconfidence in deep learning models poses a significant risk in high-stakes medical imaging tasks, particularly in multi-label classification of chest X-rays, where multiple co-occurring pathologies must be detected simultaneously. This study introduces an uncertainty-aware framework for chest X-ray diagnosis based on a DenseNet-121 backbone, enhanced with two selective prediction mechanisms: entropy-based rejection and confidence interval-based rejection. Both methods enable the model to abstain from uncertain predictions, improving reliability by deferring ambiguous cases to clinical experts. A quantile-based calibration procedure is employed to tune rejection thresholds using either global or class-specific strategies. Experiments conducted on three large public datasets (PadChest, NIH ChestX-ray14, and MIMIC-CXR) demonstrate that selective rejection improves the trade-off between diagnostic accuracy and coverage, with entropy-based rejection yielding the highest average AUC across all pathologies. These results support the integration of selective prediction into AI-assisted diagnostic workflows, providing a practical step toward safer, uncertainty-aware deployment of deep learning in clinical settings.

Mammography screening is an essential tool for early detection of breast cancer. The speed and accuracy of mammography interpretation have the potential to be improved with deep learning methods. However, the development of a foundation visual language model (VLM) is hindered by limited data and domain differences between natural and medical images. Existing mammography VLMs, adapted from natural images, often ignore domain-specific characteristics, such as multi-view relationships in mammography. Unlike radiologists who analyze both views together to process ipsilateral correspondence, current methods treat them as independent images or do not properly model the multi-view correspondence learning, losing critical geometric context and resulting in suboptimal prediction. We propose GLAM: Global and Local Alignment for Multi-view mammography for VLM pretraining using geometry guidance. By leveraging the prior knowledge about the multi-view imaging process of mammograms, our model learns local cross-view alignments and fine-grained local features through joint global and local, visual-visual, and visual-language contrastive learning. Pretrained on EMBED [14], one of the largest open mammography datasets, our model outperforms baselines across multiple datasets under different settings.

Trailblazing strides in artificial intelligence (AI) programs have led to enhanced diagnostic imaging, including ultrasound (US), magnetic resonance imaging, and infrared thermography. This systematic review summarizes current efforts to integrate AI into the diagnosis of carpal tunnel syndrome (CTS) and its potential to improve clinical decision-making. A comprehensive literature search was conducted in PubMed, Embase, and Cochrane database in accordance with PRISMA guidelines. Articles were included if they evaluated the application of AI in the diagnosis or detection of CTS. Search terms included "carpal tunnel syndrome" and "artificial intelligence", along with relevant MeSH terms. A total of 22 studies met inclusion criteria and were analyzed qualitatively. AI models, especially deep learning algorithms, demonstrated strong diagnostic performance, particularly with US imaging. Frequently used inputs included echointensity, pixelation patterns, and the cross-sectional area of the median nerve. AI-assisted image analysis enabled superior detection and segmentation of the median nerve, often outperforming radiologists in sensitivity and specificity. Additionally, AI complemented electromyography by offering insight into the physiological integrity of the nerve. AI holds significant promise as an adjunctive tool in the diagnosis and management of CTS. Its ability to extract and quantify radiomic features may support accurate, reproducible diagnoses and allow for longitudinal digital documentation. When integrated with existing modalities, AI may enhance clinical assessments, inform surgical decision-making, and extend diagnostic capabilities into telehealth and point-of-care settings. Continued development and prospective validation of these technologies are essential for streamlining widespread integration into clinical practice.

Large Language Models (LLMs) have shown strong performance in text-based healthcare tasks. However, their utility in image-based applications remains unexplored. We investigate the effectiveness of LLMs for medical imaging tasks, specifically glioma classification and segmentation, and compare their performance to that of traditional convolutional neural networks (CNNs). Using the BraTS 2020 dataset of multi-modal brain MRIs, we evaluated a general-purpose vision-language LLM (LLaMA 3.2 Instruct) both before and after fine-tuning, and benchmarked its performance against custom 3D CNNs. For glioma classification (Low-Grade vs. High-Grade), the CNN achieved 80% accuracy and balanced precision and recall. The general LLM reached 76% accuracy but suffered from a specificity of only 18%, often misclassifying Low-Grade tumors. Fine-tuning improved specificity to 55%, but overall performance declined (e.g., accuracy dropped to 72%). For segmentation, three methods - center point, bounding box, and polygon extraction, were implemented. CNNs accurately localized gliomas, though small tumors were sometimes missed. In contrast, LLMs consistently clustered predictions near the image center, with no distinction of glioma size, location, or placement. Fine-tuning improved output formatting but failed to meaningfully enhance spatial accuracy. The bounding polygon method yielded random, unstructured outputs. Overall, CNNs outperformed LLMs in both tasks. LLMs showed limited spatial understanding and minimal improvement from fine-tuning, indicating that, in their current form, they are not well-suited for image-based tasks. More rigorous fine-tuning or alternative training strategies may be needed for LLMs to achieve better performance, robustness, and utility in the medical space.

3D structural Magnetic Resonance Imaging (MRI) brain scans are commonly acquired in clinical settings to monitor a wide range of neurological conditions, including neurodegenerative disorders and stroke. While deep learning models have shown promising results analyzing 3D MRI across a number of brain imaging tasks, most are highly tailored for specific tasks with limited labeled data, and are not able to generalize across tasks and/or populations. The development of self-supervised learning (SSL) has enabled the creation of large medical foundation models that leverage diverse, unlabeled datasets ranging from healthy to diseased data, showing significant success in 2D medical imaging applications. However, even the very few foundation models for 3D brain MRI that have been developed remain limited in resolution, scope, or accessibility. In this work, we present a general, high-resolution SimCLR-based SSL foundation model for 3D brain structural MRI, pre-trained on 18,759 patients (44,958 scans) from 11 publicly available datasets spanning diverse neurological diseases. We compare our model to Masked Autoencoders (MAE), as well as two supervised baselines, on four diverse downstream prediction tasks in both in-distribution and out-of-distribution settings. Our fine-tuned SimCLR model outperforms all other models across all tasks. Notably, our model still achieves superior performance when fine-tuned using only 20% of labeled training samples for predicting Alzheimer's disease. We use publicly available code and data, and release our trained model at https://github.com/emilykaczmarek/3D-Neuro-SimCLR, contributing a broadly applicable and accessible foundation model for clinical brain MRI analysis.

BackgroundLung cancer (LC) is the leading cause of cancer mortality, often diagnosed at advanced stages. Screening reduces mortality in high-risk individuals, but its efficiency can improve with pre- and post-screening risk stratification. With recent LC screening guideline updates in Europe and the US, numerous novel risk prediction models have emerged since the last systematic review of such models. We reviewed risk-based models for selecting candidates for CT screening, and post-CT stratification. MethodsWe systematically reviewed Embase and MEDLINE (2020-2024), identifying studies proposing new LC risk models for screening selection or nodule classification. Data extraction included study design, population, model type, risk horizon, and internal/external validation metrics. In addition, we performed an exploratory meta-regression of AUCs to assess whether sample size, model class, validation type, and biomarker use were associated with discrimination. ResultsOf 1987 records, 68 were included: 41 models were for screening selection (20 without biomarkers, 21 with), and 27 for nodule classification. Regression-based models predominated, though machine learning and deep learning approaches were increasingly common. Discrimination ranged from moderate (AUC{approx}0.70) to excellent (>0.90), with biomarker and imaging-enhanced models often outperforming traditional ones. Model calibration was inconsistently reported, and fewer than half underwent external validation. Meta-regression suggested that, among pre-screening models, larger sample sizes were modestly associated with higher AUC. Conclusion75 models had been identified prior to 2020, we found 68 models since. This reflects growing interest in personalized LC screening. While many demonstrate strong discrimination, inconsistent calibration and limited external validation hinder clinical adoption. Future efforts should prioritize improving existing models rather than developing new ones, transparent evaluation, cost-effectiveness analysis, and real-world implementation.

Brain tumour detection and classification are critical for improving patient prognosis and treatment planning. However, manual identification from magnetic resonance imaging (MRI) scans is time-consuming, error-prone, and reliant on expert interpretation. The increasing complexity of tumour characteristics necessitates automated solutions to enhance accuracy and efficiency. This study introduces a novel ensemble deep learning model, boosted deformable and residual convolutional network with bi-directional convolutional long short-term memory (BDefRCNLSTM), for the classification and segmentation of brain tumours. The proposed framework integrates entropy-based local binary pattern (ELBP) for extracting spatial semantic features and employs the enhanced sooty tern optimisation (ESTO) algorithm for optimal feature selection. Additionally, an improved X-Net model is utilised for precise segmentation of tumour regions. The model is trained and evaluated on Figshare, Brain MRI, and Kaggle datasets using multiple performance metrics. Experimental results demonstrate that the proposed BDefRCNLSTM model achieves over 99% accuracy in both classification and segmentation, outperforming existing state-of-the-art approaches. The findings establish the proposed approach as a clinically viable solution for automated brain tumour diagnosis. The integration of optimised feature selection and advanced segmentation techniques improves diagnostic accuracy, potentially assisting radiologists in making faster and more reliable decisions.