Search Results (48)

The dissection of the V4 vertebral artery (VA) is the most prevalent form of intracranial dissection, which can manifest either as ischemia or as a subarachnoid hemorrhage (SAH). Patient outcomes are significantly affected by their initial presentation; ischemic symptoms often indicate that the dissection remains primarily subintimal or within the medial layer, though it can occasionally extend to the basilar artery. In contrast, patients with ruptured VA dissection (VAD) experience a considerably higher mortality rate, as the dissection can reach the adventitial layer, heightening the risk of recurrent hemorrhage. It can show fluctuating imaging findings, making an accurate diagnosis and timely treatment essential. Currently, there are no established diagnostic criteria for VAD, and its diagnosis largely depends on imaging. The presence of intramural hematoma, identified via three-dimensional, black-blood, T1-weighted imaging, has been recognized as the most reliable indicator for diagnosing VAD and is crucial for establishing a definitive diagnosis. DSA remains a fundamental diagnostic technique not only in hemorrhagic patients but also in ischemic patients. The medical treatment of ischemic patients has not yet been well defined, and evidence-based data are lacking. This review aims to summarize the main clinical, pathophysiological, and neuroradiological features of intracranial VAD presenting with ischemic stroke, providing to clinicians the available information in order to individualize the treatment. Full article

Intracranial aneurysms (IAs) are present in approximately 3–5% of the global population and carry a significant risk of rupture, leading to subarachnoid haemorrhage (SAH), a condition associated with high morbidity and mortality. Even with developments in neuroimaging, fundamental clinical difficulty remains in precisely predicting which aneurysms will rupture. Although aneurysm size, location, and patient history define traditional risk assessment, these elements by themselves have insufficient predictive ability. Key elements in rupture risk are aneurysm wall biology, haemodynamics, and inflammation; recent developments in magnetic resonance imaging (MRI) including high-resolution vascular wall imaging (VWI), 4D flow MRI, and quantitative susceptibility mapping (QSM) provide fresh insights on these aspects. The present evidence on these sophisticated MRI techniques is synthesised in this review of the literature, which also analyses their clinical relevance and addresses newly developed computational methods like machine learning for better risk stratification. I underline important studies showing the diagnostic and prognostic worth of MRI-based biomarkers, discuss present constraints, and suggest future lines of research. Personalised aneurysm care could benefit from the combination of multiparametric MRI data with artificial intelligence (AI), hence improving patient outcomes. Full article

Objective: Cerebral vascularization is made of the symmetrical arterial system, with muscular walls, and the venous system, more variable and dominated by sinuses and jugular veins. Factors like age and posture influence this network, complicating its study. Phase-contrast MRI is the gold standard for quantifying cerebral circulation. This study aimed to quantify the dynamics of the cerebral blood system using PC-MRI. Materials and Methods: Thirty-six healthy adults participated. Imaging was performed on a 3T MRI (Philips Achieva) in a supine position. Two slices were acquired: intracranial and extracranial. In-house software analyzed flow curves over a cardiac cycle. Each vessel’s contribution was evaluated. Results: Extracranial venous drainage was categorized as jugular-dominant, equivalent, or peripheral-dominant. A similar classification applied intracranially. Intracranial flows showed low variability (5–9%), while extracranial venous flows, especially in the internal jugular veins, had higher variability (17–21%). Some extracranial veins were absent. Conclusions: There is significant venous heterogeneity in the extracranial region. PC-MRI enables the quantification of cerebral dynamics. Full article

Takayasu arteritis (TAK) is a rare, chronic large-vessel vasculitis that predominantly affects the aorta and its major branches. Early and accurate diagnosis remains essential to prevent irreversible vascular damage and organ dysfunction. Positron emission tomography/computed tomography (PET/CT) has emerged as a valuable imaging modality for detecting active vascular inflammation in TAK. Using 18F-fluorodeoxyglucose (18F-FDG), PET/CT enables the assessment of metabolic activity in inflamed arterial walls, supporting both initial diagnosis and disease monitoring. Compared with conventional imaging techniques, such as magnetic resonance imaging (MRI) and computed tomography (CT), PET/CT provides functional data correlated with inflammatory activity rather than solely anatomical changes. Recent studies have highlighted its utility in distinguishing active from chronic disease, predicting relapse, and evaluating treatment response. This review summarizes the role of PET/CT in TAK, addressing its advantages, patterns of vascular involvement, limitations, and future perspectives. Vascular lesions identified using PET/CT do not always align with those detected by other imaging modalities, with PET/CT demonstrating superiority in revealing aortic inflammation potentially overlooked by alternative techniques. Further research is needed to establish whether PET/CT-based vascular involvement patterns, rather than conventional angiographic findings, can help identify disease subtypes of TAK. Full article

Background: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder. Neuropsychiatric manifestations are frequently observed and are associated with increased morbidity and reduced quality of life. Magnetic resonance imaging (MRI) is the neuroimaging procedure of choice for investigation. High-resolution vessel wall imaging (HRVWI) is a neuroimaging methodology that allows active mapping of pathophysiological processes involving brain vessel walls. Methods: To exemplify the importance of HRVWI and its usefulness in patients with SLE, we carried out a scoping review (following PRISMA guidelines) using the PubMed and Embase databases. Results: We retrieved 10 studies that utilized HRVWI in neuropsychiatric SLE, including a total of 69 patients. The majority, 84% (58/69), were women, with ages ranging between 16 and 80 years (average 38.4 years). Approximately 46.3% (32/69) of patients had white matter lesions in the brain at the time of investigation, and 77% (53/69) had normal magnetic resonance angiography. Treatment with immunosuppressants led to the resolution of the majority of the findings. Conclusions: Imaging plays an important role in investigating neuropsychiatric SLE. HRVWI analysis is gaining more importance, with its ability to identify inflammation even if angiographic MRI sequences (3D TOF) are normal, allowing the institution of early immunosuppressant treatment and resolution of symptoms. Full article

Perihematomal hypoperfusion may lead to ischemic damage during intraparenchymal cerebral hemorrhage (ICH), resulting in worse prognosis. We aimed to (1) investigate the relationship between serum biomarkers related to oxidative stress and vasoactive substances and the occurrence of hypoperfusion and ischemic perihematomal lesions in ICH and (2) evaluate their correlation with the volumetric evolution of the hematoma and perihematomal edema. We enrolled 28 patients affected by ICH. Blood samples were collected at three different time points from symptom onset: T0, T1, and T2 (admission, 12–24 h, and 48–72 h, respectively), to measure endothelin-1 (ET-1), nitrites/nitrates (NO), soluble nicotinamide adenine dinucleotide 2 (NOX2)-derived peptide (sNOX2-dp), and asymmetric dimethylarginine (ADMA). Patients underwent brain MRI with perfusion study at T1 and MRI without perfusion at T2. 12 patients had ischemic perihematomal lesions at T1. A higher sNOX2-dp concentration at T0 was observed in patients with ischemic perihematomal lesions compared to those without (p = 0.051) and with a more severe perihematomal edema at T2 (p = 0.011). The ischemic perihematomal lesions development was also associated with an increased hematoma volume (p < 0.005), perilesional edema (p = 0.046), and greater midline shift (p = 0.036). ET-1 values at T1 were inversely correlated with hemorrhage volume at T2 (ρ = −0.717, p = 0.030). NOX2 activation may have a role in the development of ischemic perihematomal lesions. The association between higher ET-1 values and a lower hemorrhage volume could be related to the ET-1 vasoconstriction action on the ruptured vessel wall. Full article

Background: The mechanism of aneurysm wall enhancement (AWE) in middle cerebral artery (MCA) bifurcation aneurysms on vessel wall magnetic resonance imaging (VW-MRI) remains unclear. We aimed to explore the morphologically related hemodynamic mechanism for the AWE of MCA bifurcation aneurysms. Methods: Patients with unruptured MCA bifurcation aneurysms undergoing VW-MRI were enrolled. Logistic regression analyses were performed to determine the risk factors for AWE. Based on the results of retrospective analyses, bifurcation aneurysm silicone models with a specific aspect ratio (AR) were designed and underwent VW-MRI with different inlet velocities. Computational fluid dynamics (CFD) analyses were conducted on both silicone models and patients’ aneurysms. Results: A total of 104 aneurysms in 95 patients (mean age 60; 34 males) were included for baseline analysis and morphological analysis. Logistic regression analysis indicated AR (OR, 5.92; 95% CI, 2.00–17.55; p = 0.001) was associated with AWE. In the high-AR group of 45 aneurysms with AWE, the aneurysm sac exhibited lower blood flow velocity, lower wall shear stress, a larger proportion of low-flow regions and higher wall enhancement values. In total, 15 silicone models were analyzed, divided into three subgroups based on neck width (4 mm, 6 mm, and 8 mm). Each subgroup contained aneurysms with five different ARs: 1.0, 1.25, 1.5, 1.75, and 2.0. In silicone models, contrast enhancement (CE) was mainly located beneath the dome of the aneurysm wall. With the same inlet velocity, CE gradually increased as the AR increased. Similarly, at the same AR, CE increased as the inlet velocity decreased. CFD demonstrated a moderate positive correlation between the near-wall enhancement index and the ratio of the low-velocity area (r = 0.6672, p < 0.001). Conclusions: The AR is associated with the AWE of MCA bifurcation aneurysms. A high AR may promote wall enhancement by causing near-wall slow flow. Full article

Background: Concentric vessel-wall contrast enhancement (VW-CE) of the terminal carotid artery and its proximal branches may be linked to ischemic strokes, disease activity and progression in Moyamoya disease (MMD). The objective of this retrospective cohort study is to analyze the association between VW-CE and perioperative acute ischemic stroke (PAIS) occurring within 24 h after revascularization. Methods: All previously untreated MMD patients who required revascularization and who had undergone preoperative MRI with VW-CE-sequences were included. PAIS was detected by CT and/or diffusion-weighted MRI sequences within 24 h postoperatively. Results: Of the 110 patients included (female-to-male ratio: 2.7:1, median age: 45.1 (16.6–69.2); n = 247 revascularizations), a priori VW-CE was present in 67.3% (mean time from MRI to first surgery: 86 days ± 82 days). PAIS occurred in five patients undergoing primary revascularization (PAIS rate per revascularization: 2.1%), all of whom had a preoperative pathological VW-CE in the vascular segment corresponding to the stroke area. Two (40%) incidents of PAIS occurred in revascularized territory, while three (60%) occurred in non-revascularized vascular territory. In each case, the supplying artery exhibited VW-CE, indicating disease activity. No additional PAIS occurred during subsequent revascularizations in cases of multistage procedures (n = 38), such as ACA or PCA revascularization as a second step. Conclusions: Preoperative VW-CE in one or more vascular segments may be a marker for postoperative stroke in the respective vascular territory at the time of revascularization. VW-CE imaging should be routinely performed when planning revascularization in MMD. If VW-CE is found, strict perioperative monitoring of these high-risk patients should be performed to achieve the best results possible. Full article

Background: Accurate measurements of flow and ventricular volume and function are critical for clinical decision-making in cardiovascular medicine. Cardiac magnetic resonance (CMR) is the current gold standard for ventricular functional evaluation but is relatively expensive and time-consuming, thus limiting the scale of clinical applications. New volumetric acquisition techniques, such as four-dimensional flow (4D-flow) and three-dimensional volumetric cine (3D-cine) MRI, could potentially reduce acquisition time without loss in accuracy; however, this has not been formally tested on a large scale. Methods: 4DCarE (4D-flow MRI for cardiovascular evaluation) is a prospective, multi-centre study designed to test the non-inferiority of a compressed 20 min exam based on volumetric CMR compared with a conventional CMR exam (45–60 min). The compressed exam utilises 4D-flow together with a single breath-hold 3D-cine to provide a rapid, accurate quantitative assessment of the whole heart function. Outcome measures are (i) flow and chamber volume measurements and (ii) overall functional evaluation. Secondary analyses will explore clinical applications of 4D-flow-derived parameters, including wall shear stress, flow kinetic energy quantification, and vortex analysis in large-scale cohorts. A target of 1200 participants will enter the study across three sites. The analysis will be performed at a single core laboratory site. Pilot Results: We present a pilot analysis of 196 participants comparing flow measurements obtained by 4D-flow and conventional 2D phase contrast, which demonstrated moderate–good consistency in ascending aorta and main pulmonary artery flow measurements between the two techniques. Four-dimensional flow underestimated the flow compared with 2D-PC, by approximately 3 mL/beat in both vessels. Conclusions: We present the study protocol of a prospective non-inferiority study of a rapid cardiac MRI exam compared with conventional CMR. The pilot analysis supports the continuation of the study. Study Registration: This study is registered with the Australia and New Zealand Clinical Trials Registry (Registry number ACTRN12622000047796, Universal Trial Number: U1111-1270-6509, registered 17 January 2022—Retrospectively registered). Full article

Background/Objectives: The aim of the study was to evaluate the usefulness of vessel wall imaging and MRI in assessment of the post-COVID-19 changes in the brain. VWI is a progressive MRI technique that provides precise imaging of the pathological process in the wall of the vessel. It might help us to better understand the pathophysiology of COVID-19-related neurological lesions and may have an impact on management protocols. Methods: A total of 43 patients were included in the study; the post-COVID-19 group included 23 patients hospitalized for COVID-19 (mean age of the group: 53.52 years; 26% male, 74% female). The control group consisted of 20 patients from the general population who did not suffer from COVID-19 (mean age: 52.15 years; 35% male, 65% female). MRI examinations were performed on a 3T scanner (Biograph mMR, Siemens). The VW-MRI protocol included T1-weighted SPACE FS black-blood images, FLAIR images, SWI, and MRA. Results: Several radiological changes in post-COVID-19 patients were described: hyperintense foci in the white matter of the brain hemispheres, in the lower parts of the temporal lobes, and in the structures of the posterior cranial fossa; presence of engorgement of deep medullary veins or perivascular enhancement; presence of inflammatory vessel thickening in VWI images; changes in hippocampus size; presence of cortical atrophy; and thickening of the mucous membrane of the paranasal sinuses. The presence of atherosclerotic vessel thickening in VWI and the width of the third ventricle depended on the age of the patient. Conclusions: VWI and MRI may be useful in the assessment of post-COVID-19 lesions in the brain. Full article

Vasculitis refers to a group of rare conditions characterized by the inflammation of blood vessels, affecting multiple systems. It presents a diagnostic and therapeutic challenge due to its broad clinical manifestations. Vasculitis is classified based on the size of the affected vessels: small, medium, large, or variable-sized. Large vessel vasculitis (LVV), particularly giant cell arteritis (GCA) and Takayasu arteritis (TAK), has garnered attention due to its significant morbidity and mortality. Both conditions involve immune-mediated inflammation of the vascular wall, despite differing in epidemiology and presentation. Early identification is crucial to prevent complications like organ ischemia and hemorrhage. Diagnostic accuracy can be hampered by false negative results, making comprehensive investigation essential. Vascular imaging, including computed tomography angiography (CTA), ultrasound (US), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT), is key in diagnosing vasculitis, revealing vessel wall thickening and other suggestive features. This article reviews typical and atypical CT and CTA findings in LVV, discusses imaging modalities, and highlights their role in therapeutic management and prognosis. It emphasizes the importance of a multidisciplinary approach and the critical role of radiologists in improving patient outcomes in LVV. Full article

Atherosclerosis involves an inflammatory response due to plaque formation within the arteries, which can lead to ischemic stroke and heart disease. It is one of the leading causes of death worldwide, with various contributing factors such as hyperlipidemia, hypertension, obesity, diabetes, and smoking. Wall shear stress (WSS) is also known as a contributing factor of the formation of atherosclerotic plaques. Since the causes of atherosclerosis cannot be attributed to a single factor, clearly understanding the mechanisms and causes of its occurrence is crucial for preventing the disease and developing effective treatment strategies. To better understand atherosclerosis and define the correlation between various contributing factors, computational fluid dynamics (CFD) analysis is primarily used. CFD simulates WSS, the frictional force caused by blood flow on the vessel wall with various hemodynamic changes. Using apolipoprotein E knockout (ApoE-KO) mice subjected to partial ligation and a high-fat diet at 1-week, 2-week, and 4-week intervals as an atherosclerosis model, CFD analysis was conducted along with the reconstruction of carotid artery blood flow via magnetic resonance imaging (MRI) and compared to the inflammatory factors and pathological staining. In this experiment, a comparative analysis of the effects of high WSS and low WSS was conducted by comparing the standard deviation of time-averaged wall shear stress (TAWSS) at each point within the vessel wall. As a novel approach, the standard deviation of TAWSS within the vessel was analyzed with the staining results and pathological features. Since the onset of atherosclerosis cannot be explained by a single factor, the aim was to find the correlation between the thickness of atherosclerotic plaques and inflammatory factors through standard deviation analysis. As a result, the gap between low WSS and high WSS widened as the interval between weeks in the atherosclerosis mouse model increased. This finding not only linked the occurrence of atherosclerosis to WSS differences but also provided a connection to the causes of vulnerable plaques. Full article

Acute ischemic stroke in young adults typically carries significant implications for morbidity, mortality, and long-term disability. In this study, we describe the case of a 34-year-old male with no prior medical history who presented with symptoms of right-sided weakness and slurred speech, suggesting an acute ischemic stroke. Initial CT angiography revealed an occlusion in the left M2 segment middle cerebral artery (MCA). The occlusion was successfully recanalized through emergent endovascular thrombectomy, which also identified a dissection as the cause of the stroke. Follow-up assessments at 3 days and three months, which included advanced vessel wall MRI, highlighted the critical role of intracranial artery dissection in strokes among young adults and provided essential images for ongoing evaluation. Full article

A prospective study on 110 patients with echinococcosis at Dr. Khuroo’s Medical Clinic, Srinagar, Kashmir, India, from March 2019 to April 2024 identified 12 cases (4 males, 8 females; mean age of 46.58 ± 11.97 years) of Alveolar echinococcosis (AE). Two patients were detected through ultrasound examinations carried out for unrelated causes; one presented with features of liver abscess, and nine had pain in the right upper quadrant for a mean period of 2.2 ± 1.79 years. All had the liver as the primary organ involved, with 15 tumor masses of a mean maximum diameter of 9.22 ± 3.21 cm and volume of 426 ± 374.61 cm³. Tumors placed centrally had invaded vessels and the biliary tract in eight patients, and those placed peripherally had invaded the liver capsule and adjacent organs in nine patients. Histologic examination of liver biopsies or resected organs revealed necrotic lesions, calcifications, and granulomatous inflammation with slender, thin-walled vesicles of bizarre configuration that stained strongly eosinophilic with periodic acid Schiff. Two patients had segmental liver resections; one was treated with liver aspiration, while the other nine with advanced disease received chemotherapy with albendazole along with praziquantel. Patients showed clinical improvement on a median follow-up of 12 months (range 1 to 60 months); however, MRI T2-weighted images and ¹⁸F-FDG-PET-CECT scans in two patients showed active disease on follow-up at one and five years, respectively. A systematic review detected 146 cases of AE in India from 1980 to April 2024. Twenty cases were from foreign countries, mostly from Central Asian republics, and 118 (93.65%) of the remaining 126 Indian patients were permanent residents of Kashmir Valley. The disease affected a population of 79,197 residing in 22 villages from 5 border districts of the valley. These villages were either high in or adjacent to the Himalayan mountain range. Disease prevalence in the affected population was 146.47/10⁵ (males 131.53/10⁵ and females 163.18/10⁵) and the incidence was 12.41/10⁵/year (males 11.16/10⁵/year and females 13.81/10⁵/year). Possible causes of the emergence of AE are discussed, and future directions for research to face this challenge arebeen identified. Full article

Background: To describe high-resolution brain vessel wall MRI (VW-MRI) patterns and morphological brain findings in central nervous system (CNS) vasculitis patients. Methods: Fourteen patients with confirmed CNS Vasculitis from two tertiary centers underwent VW-MRI using a 3T scanner. The images were reviewed by two neuroradiologists to assess vessel wall enhancement characteristics and locations. Results: Fourteen patients were included (six females; average age 48 ± 19 years). Diagnoses included primary CNS vasculitis (PCNSV) in six patients and secondary CNS vasculitis (SCNSV) in eight, half of which were infection-related. Thirteen patients showed vessel wall enhancement, which was intense in eleven patients (84.6%) and concentric in twelve (92.3%), affecting the anterior circulation in nine patients (69.2%), posterior in two patients (15.4%), and both circulations in two patients (15.4%). The enhancement patterns were similar across different CNS vasculitis types. DWI changes corresponded with areas of vessel wall enhancement in 77% of patients. Conclusions: CNS vasculitis is often associated with intense, concentric vessel wall enhancement in VW-MRI, especially in the anterior circulation. The consistent presence of DWI alterations in affected territories suggests a possible link to microembolization or hypoperfusion. These imaging findings complement parenchymal brain MRI and MRA/DSA data, potentially increasing the possibility of a clinical diagnosis of CNS vasculitis. Full article