Unexplained cardiac arrest after near drowning in a young experienced swimmer: insight from cardiovascular magnetic resonance imaging

Cardiac magnetic resonance imaging (cMRI) is a well-established noninvasive imaging modality in clinical cardiology. Its ability to provide tissue characterization make it well suited for the study of patients with cardiac diseases. We describe a multi-modality imaging evaluation of a 45-year-old man who experienced a near drowning event during swimming. We underline the unique capability of tissue characterization provided by cMRI, which allowed detection of subtle, clinically unrecognizable myocardial damage for understanding the causes of sudden cardiac arrest and also showed the small damages caused by cardiopulmonary resuscitation

Sulfuric acid ingestion: may the severity of the metabolic acidosis be considered as a predictive sign of late damage to the gastrointestinal tract?

Introduction: Caustic substances ingestion results in a complex syndrome. The patient characteristics and severity of injury are important prognostic predictors. The monitoring of clinical changes and the multidisciplinary approach are necessary to prevent death in the early stages of the poisoning. Case description: The case report describes the suicide of a woman by ingestion of a large amount of 15% sulfuric acid for suicidal purposes (15–20 ml). The initial conditions were stable, and no changes were found on a CT scan. However, the main sign was a severe metabolic acidosis. After 7 hours, haematemesis and oedema of the larynx appeared, and oro-tracheal intubation and ICU admission were necessary. Consequent progressive haemodynamic deterioration with persistent severe metabolic acidosis, increasing lactates and septic shock appeared. A new CT scan with contrast was performed 22 hours later detecting diffuse perforations and liquid in pleurae and abdomen. A pleural sample showed necrotic liquid. The death was 24 hours after ingestion and no surgical treatment was performed because of the diffuse lesions to the thoracoabdominal districts. Conclusions: Early detection of gastroenteric lesions and the monitoring of clinical changes are mandatory to avoid the death of the patient. Gastroenteric perforations require an immediate radiological evaluation and surgical treatment. The clinical case report states the severity of prognosis was related to high doses of sulfuric acid ingestion. The immediate metabolic acidosis is related to quick subsequent severe systemic pathological lesions of the gastrointestinal tract. The severity of absorption metabolic acidosis, consequently, may be an early and prognostic sign of the late chest and abdominal lesions

San Carlo dei Barnabiti: restoration and reinforcement of the roofing of a florentine baroque masterpiece

The church of San Carlo dei Barnabiti houses one of the most important examples of Baroque illusionistic painting in Florence. Given the level of deterioration of the vault, the preliminary investigations required a 3D survey of the current geometry to detect the mainly damaged areas. A point cloud obtained by laser scanning is employed to investigate the deformations and the state of conservation of the vault. The acquired data also revealed some unknown aspects concerning the construction of the structure and its pictorial decoration useful to design the restoration project

Low-dose coronary calcium scoring CT using a dedicated reconstruction filter for kV-independent calcium measurements

In this prospective, pilot study, we tested a kV-independent coronary artery calcium scoring CT protocol, using a novel reconstruction kernel (Sa36f). From December 2018 to November 2019, we performed an additional research scan in 61 patients undergoing clinical calcium scanning. For the standard protocol (120 kVp), images were reconstructed with a standard, medium-sharp kernel (Qr36d). For the research protocol (automated kVp selection), images were reconstructed with a novel kernel (Sa36f). Research scans were sequentially performed using a higher (cohort A, n = 31) and a lower (cohort B, n = 30) dose optimizer setting within the automatic system with customizable kV selection. Agatston scores, coronary calcium volumes, and radiation exposure of the standard and research protocol were compared. A phantom study was conducted to determine inter-scan variability. There was excellent correlation for the Agatston score between the two protocols (r = 0.99); however, the standard protocol resulted in slightly higher Agatston scores (29.4 [0-139.0] vs 17.4 [0-158.2], p = 0.028). The median calcium volumes were similar (11.5 [0-109.2] vs 11.2 [0-118.0] mm(3); p = 0.176), and the number of calcified lesions was not significantly different (p = 0.092). One patient was reclassified to another risk category. The research protocol could be performed at a lower kV and resulted in a substantially lower radiation exposure, with a median volumetric CT dose index of 4.1 vs 5.2 mGy, respectively (p < 0.001). Our results showed that a consistent coronary calcium scoring can be achieved using a kV-independent protocol that lowers radiation doses compared to the standard protocol

Demographic Bias of Expert-Level Vision-Language Foundation Models in Medical Imaging

Advances in artificial intelligence (AI) have achieved expert-level performance in medical imaging applications. Notably, self-supervised vision-language foundation models can detect a broad spectrum of pathologies without relying on explicit training annotations. However, it is crucial to ensure that these AI models do not mirror or amplify human biases, thereby disadvantaging historically marginalized groups such as females or Black patients. The manifestation of such biases could systematically delay essential medical care for certain patient subgroups. In this study, we investigate the algorithmic fairness of state-of-the-art vision-language foundation models in chest X-ray diagnosis across five globally-sourced datasets. Our findings reveal that compared to board-certified radiologists, these foundation models consistently underdiagnose marginalized groups, with even higher rates seen in intersectional subgroups, such as Black female patients. Such demographic biases present over a wide range of pathologies and demographic attributes. Further analysis of the model embedding uncovers its significant encoding of demographic information. Deploying AI systems with these biases in medical imaging can intensify pre-existing care disparities, posing potential challenges to equitable healthcare access and raising ethical questions about their clinical application.Comment: Code and data are available at https://github.com/YyzHarry/vlm-fairnes

A highly-detailed anatomical study of left atrial auricle as revealed by in-vivo computed tomography

The left atrial auricle (LAA) is the main source of intracardiac thrombi, which contribute significantly to the total number of stroke cases. It is also considered a major site of origin for atrial fibrillation in patients undergoing ablation procedures. The LAA is known to have a high degree of morphological variability, with shape and structure identified as important contributors to thrombus formation. A detailed understanding of LAA form, dimension, and function is crucial for radiologists, cardiologists, and cardiac surgeons.This review describes the normal anatomy of the LAA as visualized through multiple imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and echocardi-ography. Special emphasis is devoted to a discussion on how the morphological characteristics of the LAA are closely related to the likelihood of developing LAA thrombi, including insights into LAA embryology

Optimization of window settings for coronary arteries assessment using spectral CT-derived virtual monoenergetic imaging

Purpose: To determine the optimal window setting for virtual monoenergetic images (VMI) reconstructed from dual-layer spectral coronary computed tomography angiography (DE-CCTA) datasets. Material and methods: 50 patients (30 males; mean age 61.1 ± 12.4 years who underwent DE-CCTA from May 2021 to June 2022 for suspected coronary artery disease, were retrospectively included. Image quality assessment was performed on conventional images and VMI reconstructions at 70 and 40 keV. Objective image quality was assessed using contrast-to-noise ratio (CNR). Two independent observers manually identified the best window settings (B-W/L) for VMI 70 and VMI 40 visualization. B-W/L were then normalized with aortic attenuation using linear regression analysis to obtain the optimized W/L (O-W/L) settings. Additionally, subjective image quality was evaluated using a 5-point Likert scale, and vessel diameters were measured to examine any potential impact of different W/L settings. Results: VMI 40 demonstrated higher CNR values compared to conventional and VMI 70. B-W/L settings identified were 1180/280 HU for VMI 70 and 3290/900 HU for VMI 40. Subsequent linear regression analysis yielded O-W/L settings of 1155/270 HU for VMI 70 and 3230/880 HU for VMI 40. VMI 40 O-W/L received the highest scores for each parameter compared to conventional (all p &lt; 0.0027). Using O-W/L settings for VMI 70 and VMI 40 did not result in significant differences in vessel measurements compared to conventional images. Conclusion: Optimization of VMI requires adjustments in W/L settings. Our results recommend W/L settings of 1155/270 HU for VMI 70 and 3230/880 HU for VMI 40.</p