Multiscale optoacoustic assessment of skin microvascular reactivity in carotid artery disease.

Microvascular endothelial dysfunction may provide insights into systemic diseases, such as carotid artery disease. Raster-scan optoacoustic mesoscopy (RSOM) can produce images of skin microvasculature during endothelial dysfunction challenges via numerous microvascular features. Herein, RSOM was employed to image the microvasculature of 26 subjects (13 patients with single carotid artery disease, 13 healthy participants) to assess the dynamics of 18 microvascular features at three scales of detail, i.

Is the Eversion Technique Associated with Lower Peri-operative Stroke or Death Compared with Carotid Endarterectomy with Patch Angioplasty? Secondary Data Analysis of the German Statutory Quality Assurance Database.

Objective: Various studies have failed to detect a difference in outcomes between carotid endarterectomy (CEA) with patch angioplasty and eversion CEA. This study aimed to assess whether surgical technique and related department policy are associated with in hospital outcomes after CEA.

Methods: This was a secondary data analysis based on the German statutory quality assurance database.

Association of Centre Quality Certification with Characteristics of Patients, Management, and Outcomes Following Carotid Endarterectomy or Carotid Artery Stenting.

The aim of this study was to analyze the association between center quality certifications and patients' characteristics, clinical management, and outcomes after carotid revascularization. This study is a pre-planned sub-study of the ISAR-IQ project, which analyzes data from the Bavarian subset of the nationwide German statutory quality assurance carotid database. Hospitals were classified as to whether a certified vascular center (cVC) or a certified stroke unit (cSU) was present on-site or not.

Determinants of Pre- and Post-Procedural Neurological Assessment, and Outcome of Carotid Endarterectomy or Stenting.

The German-Austrian guideline on the treatment of carotid stenosis recommends specialist neurological assessment (NA) before and after carotid endarterectomy (CEA) or carotid artery stenting (CAS). This study analyzes the determinants of NA and the association of NA with the perioperative rate of stroke or death. This study is a pre-planned sub-study of the ISAR-IQ project, which analyzes data from the nationwide German statutory quality assurance carotid database.

Determinants of prehospital and in-hospital delay in patients with symptomatic carotid stenosis and their influence on the outcome after elective carotid endarterectomy.

Background: This study analyses the determinants of prehospital (index event to admission) and in-hospital delay (admission to carotid endarterectomy (CEA)). In addition, the analysis addresses the association between prehospital or in-hospital delay and outcomes after CEA for symptomatic patients in German hospitals.

Materials And Methods: This retrospective analysis is based on the nationwide German statutory quality assurance database.

Use of an embolic protection device during carotid artery stenting is associated with lower periprocedural risk.

Objective: To investigate associations between individual embolic protection device (EPD) use and respective center policy with periprocedural outcomes after carotid artery stenting (CAS).

Methods: This analysis is based on the nationwide German statutory quality assurance database and was funded by Germany's Federal Joint Committee Innovation Fund (G-BA Innovationsfonds, 01VSF19016 ISAR-IQ). According to their policy towards EPD use, hospitals were categorized as (>90%), (10-90%), or (<10%) .

Association between hospital ownership and patient selection, management, and outcomes after carotid endarterectomy or carotid artery stenting : - Secondary data analysis of the Bavarian statutory quality assurance database.

Background: This study analyses the association between hospital ownership and patient selection, treatment, and outcome of carotid endarterectomy (CEA) or carotid artery stenting (CAS).

Methods: The analysis is based on the Bavarian subset of the nationwide German statutory quality assurance database. All patients receiving CEA or CAS for carotid artery stenosis between 2014 and 2018 were included.

Intraoperative Completion Studies and their Associations with Carotid Endarterectomy Outcomes.

Objective: This study aimed at assessing outcomes after carotid endarterectomy (CEA) in dependence of center policy with respect to imaging intraoperative completion study (ICS i ) usage.

Summary Background Data: Although randomized controlled studies are missing, a beneficial effect was shown for ICS i techniques (i.e.

Macro- and microvascular contributions to cerebral structural alterations in patients with asymptomatic carotid artery stenosis.

Atherosclerosis can underly internal carotid artery stenosis (ICAS), a major risk factor for ischemic stroke, as well as small vessel disease (SVD). This study aimed to investigate hemodynamics and structural alterations associated with SVD in ICAS patients. 28 patients with unilateral asymptomatic ICAS and 30 age-matched controls underwent structural (T1-/T2-weighted and diffusion tensor imaging [DTI]) and hemodynamic (pseudo-continuous arterial spin labeling and dynamic susceptibility contrast) magnetic resonance imaging.

Spectral computed tomography angiography using a gadolinium-based contrast agent for imaging of pathologies of the aorta.

Objectives: Especially patients with aortic aneurysms and multiple computed tomography angiographies (CTA) might show medical conditions which oppose the use of iodine-based contrast agents. CTA using monoenergetic reconstructions from dual layer CT and gadolinium (Gd-)based contrast agents might be a feasible alternative in these patients. Therefore, the purpose of this study was to evaluate the feasibility of clinical spectral CTA with a Gd-based contrast agent in patients with aortic aneurysms.

Endovascular aortic repair with sac embolization for the prevention of type II endoleaks (the EVAR-SE study): study protocol for a randomized controlled multicentre study in Germany.

Background: Beyond a certain threshold diameter, abdominal aortic aneurysms (AAA) are to be treated by open surgical or endovascular aortic aneurysm repair (EVAR). In a quarter of patients who undergo EVAR, inversion of blood flow in the inferior mesenteric artery or lumbar arteries may lead to type II endoleak (T2EL), which is associated with complications (e.g.

Dermal features derived from optoacoustic tomograms via machine learning correlate microangiopathy phenotypes with diabetes stage.

Skin microangiopathy has been associated with diabetes. Here we show that skin-microangiopathy phenotypes in humans can be correlated with diabetes stage via morphophysiological cutaneous features extracted from raster-scan optoacoustic mesoscopy (RSOM) images of skin on the leg. We obtained 199 RSOM images from 115 participants (40 healthy and 75 with diabetes), and used machine learning to segment skin layers and microvasculature to identify clinically explainable features pertaining to different depths and scales of detail that provided the highest predictive power.

Optoacoustic biomarkers of lipids, hemorrhage and inflammation in carotid atherosclerosis.

Imaging plays a critical role in exploring the pathophysiology and enabling the diagnostics and therapy assessment in carotid artery disease. Ultrasonography, computed tomography, magnetic resonance imaging and nuclear medicine techniques have been used to extract of known characteristics of plaque vulnerability, such as inflammation, intraplaque hemorrhage and high lipid content. Despite the plethora of available techniques, there is still a need for new modalities to better characterize the plaque and provide novel biomarkers that might help to detect the vulnerable plaque early enough and before a stroke occurs.

Clinical and Translational Imaging and Sensing of Diabetic Microangiopathy: A Narrative Review.

Microvascular changes in diabetes affect the function of several critical organs, such as the kidneys, heart, brain, eye, and skin, among others. The possibility of detecting such changes early enough in order to take appropriate actions renders the development of appropriate tools and techniques an imperative need. To this end, several sensing and imaging techniques have been developed or employed in the assessment of microangiopathy in patients with diabetes.

Stronger influence of systemic than local hemodynamic-vascular factors on resting-state BOLD functional connectivity.

Correlated fluctuations in the blood oxygenation level dependent (BOLD) signal of resting-state functional MRI (i.e., BOLD-functional connectivity, BOLD-FC) reflect a spectrum of neuronal and non-neuronal processes.

Opening a window to skin biomarkers for diabetes stage with optoacoustic mesoscopy.

Being the largest and most accessible organ of the human body, the skin could offer a window to diabetes-related complications on the microvasculature. However, skin microvasculature is typically assessed by histological analysis, which is not suited for applications to large populations or longitudinal studies. We introduce ultra-wideband raster-scan optoacoustic mesoscopy (RSOM) for precise, non-invasive assessment of diabetes-related changes in the dermal microvasculature and skin micro-anatomy, resolved with unprecedented sensitivity and detail without the need for contrast agents.

Hemodynamic MRI parameters to predict asymptomatic unilateral carotid artery stenosis with random forest machine learning.

Background: Internal carotid artery stenosis (ICAS) can cause stroke and cognitive decline. Associated hemodynamic impairments, which are most pronounced within individual watershed areas (iWSA) between vascular territories, can be assessed with hemodynamic-oxygenation-sensitive MRI and may help to detect severely affected patients. We aimed to identify the most sensitive parameters and volumes of interest (VOI) to predict high-grade ICAS with random forest machine learning.

Bony Stroke: Ischemic Stroke Caused by Mechanical Stress on Brain Supplying Arteries From Anatomical Bone or Cartilage Anomalies.

Background: Bone or cartilage anomalies with affection of brain supplying arteries are a potential structural cause for ischemic stroke. In the following, we termed this entity bony stroke. Due to rarity of their description, there is no standardized workup and therapy for bony strokes.

Skeletal muscle optoacoustics reveals patterns of circulatory function and oxygen metabolism during exercise.

Imaging skeletal muscle function and metabolism, as reported by local hemodynamics and oxygen kinetics, can elucidate muscle performance, severity of an underlying disease or outcome of a treatment. Herein, we used multispectral optoacoustic tomography (MSOT) to image hemodynamics and oxygen kinetics within muscle during exercise. Four healthy volunteers underwent three different hand-grip exercise challenges (60s isometric, 120s intermittent isometric and 60s isotonic).

Non-invasive multispectral optoacoustic tomography resolves intrahepatic lipids in patients with hepatic steatosis.

Hepatic steatosis is characterized by intrahepatic lipid accumulation and may lead to irreversible liver damage if untreated. Here, we investigate whether multispectral optoacoustic tomography (MSOT) can offer label-free detection of liver lipid content to enable non-invasive characterization of hepatic steatosis by analyzing the spectral region around 930 nm, where lipids characteristically absorb. In a pilot study, we apply MSOT to measure liver and surrounding tissues in five patients with liver steatosis and five healthy volunteers, revealing significantly higher absorptions at 930 nm in the patients, while no significant difference was observed in the subcutaneous adipose tissue of the two groups.