Magnetic Resonance Imaging Angiography Research Articles

The Significance of the Intercarotid Distances for Transsphenoidal Pituitary Surgery: A Magnetic Resonance Imaging Study

We performed MRI to analyze the distance between the left and right internal carotid arteries (ICD) around pituitary tumors for transsphenoidal surgery (TSS). Measurements were performed using thin slice T2-weighted MRI, and/or time-of-flight MR angiography imaging for 64 non-functioning pituitary neuroendocrine tumors (NF-pitNETs), 22 growth hormone-producing pitNETs (GH producing pitNETs), and 46 normal controls. We measured the ICD at 3 anatomic levels: at the distal dural ring (ICD-A); at the most concave point of the C4-C5 bend (ICD-B); and at the most convex point of the C4 bend (ICD-C). Additionally, we measured the sagittal distance between the tuberculum selle and the junction of the sellar floor and clivus on the mid sagittal MRI (TS-C). We found that ICD-B was the longest and that ICD-A was the shortest among the three distance parameters in all groups (P<0.001). The comparison of the groups revealed that the NF-pitNET group had longer distances than the normal control group at all ICDs (P<0.001). The GH producing pitNET group had longer distance than the normal control group at ICD-B (P<0.001). Tumor volume was correlated with ICD-A and ICD-B in the NF-pitNET, and was correlated with ICD-C in the GH producing pitNET group. Among the distance parameters, ICD-B is the longest, and was approximately twice the width of the TS-C. The shape of the sella is an ellipse that is widest in the lateral dimension in TSS. A horizontal based dural incision may be more rational than a conventional X-shaped dural incision.

Vessel distance mapping: A novel methodology for assessing vascular-induced cognitive resilience

The association between cerebral blood supply and cognition has been widely discussed in the recent literature. One focus of this discussion has been the anatomical variability of the circle of Willis, with morphological differences being present in more than half of the general population. While previous studies have attempted to classify these differences and explore their contribution to hippocampal blood supply and cognition, results have been controversial. To disentangle these previously inconsistent findings, we introduce Vessel Distance Mapping (VDM) as a novel methodology for evaluating blood supply, which allows for obtaining vessel pattern metrics with respect to the surrounding structures, extending the previously established binary classification into a continuous spectrum. To accomplish this, we manually segmented hippocampal vessels obtained from high-resolution 7T time-of-flight MR angiographic imaging in older adults with and without cerebral small vessel disease, generating vessel distance maps by computing the distances of each voxel to its nearest vessel. Greater values of VDM-metrics, which reflected higher vessel distances, were associated with poorer cognitive outcomes in subjects affected by vascular pathology, while this relation was not observed in healthy controls. Therefore, a mixed contribution of vessel pattern and vessel density is proposed to confer cognitive resilience, consistent with previous research findings. In conclusion, VDM provides a novel platform, based on a statistically robust and quantitative method of vascular mapping, for addressing a variety of clinical research questions.

The effectiveness of MRI and CT with intravenous contrast in the assessment of carotid chemodectoma at the preoperative stage and in dynamics after surgery

Background. Carotid chemodectoma is rare, slow growing, richly vascularized lesion. It is a single unilateral or bilateral tumor, localized mainly in the area of the carotid triangle. Different forms and bilateral cases are also known. A complex of radiological studies, including MRI and CT with intravenous contrast, can help in determining the surgical treatment strategy, as well as treatment monitoring. Objective. To determine the role of MRI and CT with intravenous contrast in the assessment of carotid chemodectoma at the preoperative stage and at post-surgery monitoring. Materials and Methods. We analyzed the results of a comprehensive radiological examination of 12 patients with suspected carotid chemodectoma, including MRI and MSCT with intravenous contrast, and X-ray angiography. All patients got operated, the results were confirmed by histological and immunohistochemical study. Results. Multislice computed tomography, supplemented by CT angiography, allows visualizing chemodectoma, determining its size, shape, structure, and relations with the nearby vessels. In addition to size, shape, structure of chemodectoma MRI can provide a detailed picture of the internal vascular network, the walls of adjacent vascular structures, as well as the soft tissue structures of the peripharyngeal area, which is helpful for vascular surgeons in surgical intervention. It was not possible to determine the histogenesis of the tumor according to the methods of radiation diagnostics. Conclusions. In order to determine the option of surgical treatment of carotid chemodectomas and reduce the risk of intraoperative complications at the preoperative stage, it is necessary to carry out the entire spectrum of radiation diagnostic methods (including ultrasound, MSCT, MRI and X-ray angiography).

A RARE PRESENTATION OF DELAYED EPISTAXIS: POST TRAUMATIC INTERNAL CAROTID ARTERY PSEUDOANEURYSM AT A TERTIARY CARE CENTRE IN EASTERN NEPAL

Epistaxis is a common ENT emergency. Various causes are mucosal trauma, anticoagulants and bleeding disorders. Vascular causes and trauma accounts for less than 5% causes. A 25-year-old man presented to emergency with intractable epistaxis. He had sustained road traffic accident 5 months back. His previous CT scan showed multiple facial bones fracture along with sinuses (frontal, maxillary and sphenoid sinus on right para clinoid area) fracture. Initial CT angiography showed no vascular defects. The latest episode of epistaxis was massive and he underwent nasal endoscopy and packing of nose. Pulsatile sphenoidal polyp was visualized, along with transmitted pulsations in the sphenoid sinus on the right side. Subsequent Magnetic Resonance Angiography (MRA) showed a 12x4 mm pseudoaneurysm of clinoidal portion of Internal Carotid Artery on the right side. Post-traumatic Pseudoaneurysm of the Internal Carotid Artery may be the differential diagnosis in traumatic epistaxis, especially the delayed type. If pseudoaneurysm is suspected, CT or MRI angiography should be performed immediately.

Prevention of in-stent restenosis with drug-eluting balloons in patients with postirradiated carotid stenosis accepting percutaneous angioplasty and stenting

ObjectiveTo investigate the technical safety and outcome of in-stent restenosis (ISR) prevention with drug-eluting balloon (DEB) in patients with postirradiated carotid stenosis (PIRCS) undergoing percutaneous angioplasty and stenting (PTAS).MethodsBetween 2017...

Use of Non-Contrast-Enhanced MR Angiography to Assess Recanalization after Uterine Artery Embolization

The purpose of this study was to examine the use of non-contrast-enhanced MR angiography (MRA) for assessing recanalization of uterine arteries (UAs) after uterine artery embolization (UAE) for symptomatic fibroids. Pre-procedural and follow-up unenhanced MRA images of 30 patients were reviewed, and the extent to which the UAs could be visualized was classified on a 4-point scale. An increase in the score between consecutive time points indicates that a previously inconspicuous segment of the UA became visible on follow-up images. Patients were divided into two groups according to the presence (or absence) of recanalization. The median UA visualization score at each follow-up was significantly lower than that at baseline (p < 0.01), but there was no significant difference between the scores of the follow-up images. Recanalization was detected in 63% (19/30) of patients. In these patients, the mean decrease in uterine and largest fibroid volume at 12 months after UAE was inferior to the mean decrease in patients for whom recanalization was not detected. Based on MRA assessment, recanalization after UAE occurred in 63% of patients but did not compromise the reduction in uterine and dominant fibroid volumes within 12 months after UAE.

Radiomics Nomogram Model Based on TOF-MRA Images: A New Effective Method for Predicting Microaneurysms.

To develop a radiomics nomogram model based on time-of-flight magnetic resonance angiography (TOF-MRA) images for preoperative prediction of true microaneurysms. 118 patients with Intracranial Aneurysm Sac (40 positive and 78 negative) were enrolled and allocated to training and validation groups (8:2 ratio). Findings of clinical characteristics and MRA features were analyzed. A radiomics signature was built on the basis of reproducible features by using the least absolute shrinkage and selection operator (LASSO) regression algorithm in the training group. The radiomics nomogram model was constructed by combining clinical risk factors and radiomics signature.In order to compare the classification performance of clinical models, radiomics model and radiomics nomogram model, AUC was used to evaluate them.The performance of the radiomics nomogram model was evaluated by calibration curve and decision curve analysis. Eleven features were selected to develop radiomics model with AUC of 0.875 (95% CI 0.78-0.97), sensitivity of 0.84, and specificity of 0.68. The radiomics model achieved a better diagnostic performance than the clinic model (AUC = 0.75, 95% CI: 0.53-0.97) and even radiologists. The radiomics nomogram model, which combines radiomics signature and clinical risk factors, is effective too (AUC = 0.913, 95% CI: 0.87-0.96). Furthermore, the decision curve analysis demonstrated significantly better net benefit in the radiomics nomogram model. Radiomics features derived from TOF-MRA can reliably be used to build a radiomics nomogram model for effectively differentiating between pseudo microaneurysms and true microaneurysms, and it can provide an objective basis for the selection of clinical treatment plans.

Intracranial arterial flow velocity mapping in quantitative time-of-flight MR angiography using deep machine learning

PurposeTo evaluate the application of deep machine learning (DML) to 3D quantitative time-of-flight (qTOF) magnetic resonance angiography (MRA) to measure blood flow velocity within the intracranial arteries. Materials and methodsIntracranial qTOF MRA was acquired in 15 subjects at 3 T. Blood flow velocity quantitation with qTOF MRA was done using a non-DML computer-vision procedure, and using convolutional DML neural networks. 3D phase contrast (PC) MRA was used as the comparator. Using PC velocity measures as the output target and qTOF two-echo source image data as inputs, DML neural networks were trained to predict component blood flow velocities. Total velocities and peak intracranial arterial blood flow velocities were computed from component velocities. ResultsCompared to non-DML image analysis, DML-based analysis of qTOF MRA image data improved agreement with PC for mean component velocity (intraclass correlation coefficient (ICC) = 0.966 versus 0.939), mean total velocity (ICC = 0.835 versus 0.723), and peak velocity (ICC = 0.816 versus 0.597), as well as narrowed the 95% Bland-Altman limits of agreement for mean component velocity ([−5.16, +4.31]cm/s versus [−6.86, +6.53]cm/s), mean total velocity ([−6.78,+3.59]cm/s versus [−9.39, +7.09]cm/s) and peak velocity ([−13.5,+10.2]cm/s versus [−21.3, +10.2]cm/s). Compared to non-DML analysis, DML image analysis reduced the root-mean-square deviation from PC velocity measures by 28%–36%, and shortened calculation times by 35-fold. ConclusionThe application of DML image analysis to intracranial qTOF MRA for velocity quantitation markedly shortened calculation times, substantially improved the agreement of component, total, and peak arterial blood flow velocities, and provided excellent agreement of hemodynamic measures with respect to 3D PC.

MR angiography facilitates the differentiation of aneurysmal from unicameral bone cysts.

The objective of this work was to evaluate the incremental value of MR angiography over plain radiographs and MRI for the differentiation of aneurysmal bone cysts (ABCs) from unicameral bone cysts (UBCs). Thirty-six juvenile patients with histologically secured primary ABCs or UBCs were included in this retrospective study. Two radiologists assessed all obtained images in a blinded fashion using a catalog of previously suggested imaging findings. A second readout with supplementary MR angiography images was performed after 8 weeks to prevent observer recall bias. Diagnostic accuracy parameters were calculated for individual imaging findings, and overall diagnostic accuracy and diagnostic confidence were assessed for all readouts. Receiver operating characteristic (ROC) curve comparison was used to determine the incremental value of MR angiography. Of 16 imaging features, only abnormal vascularization in MR angiography provided sufficient diagnostic accuracy for the identification of ABCs. Other imaging features such as fluid-fluid levels and internal septations were insufficient for the differentiation of UBCs from ABCs. Availability of MR angiography images significantly increased diagnostic accuracy (94.4 vs 75.0% and 83.3 vs 69.4%, respectively, p < 0.05) and diagnostic confidence (4.5 vs 3.7, p < 0.05) of reading radiologists. The presence of arterial feeders in MR angiography can accurately discriminate primary ABCs from UBCs and increases the diagnostic accuracy and diagnostic confidence of reporting radiologists. Radiographic differentiation of cystic bone lesions such as ABCs and UBCs remains challenging. We demonstrate that MR angiography provides incremental value and suggest inclusion in standard examination protocols.

Evaluating the length, diameter, and stenosis of deep circumflex iliac artery and neighboring arteries based on digital subtraction angiography.

The vascularized iliac bone crest flap offers excellent usable bone in terms of volume and quality. Its nourishing vessel, the deep circumflex iliac artery (DCIA), although relatively short, is reliable vessel. Digital subtraction angiography presents still the gold standard for diagnostic purpose. However, computed tomography (CT) and magnetic resonance imaging (MRI) angiography is used for preoperative planning with low morbidity. The purpose of this study is to evaluate the gainable information using digital subtraction angiography (DSA) as compared to other imaging modalities. We evaluated information gainable from standard DSA of 130 consecutive patients (average age was 69.5 years [range 18-90 years]) concerning topography, dimension, and condition of the vessel wall. We looked for differences considering gender and side. DCIA could not be followed in the periphery constantly in all cases due to the small, illustrated field. Arteriosclerotic changes showed to be very low in DCIA as compared to the neighboring vessels. Diabetes mellitus and smoking had a significant impact on vessel condition. DCIA branched off into its main two branches early after 40 mm (11%), after 40-60 mm (30%), or late after 60 mm (59%). DCIA showed to be least affected by different risk factors that reported to affect the vessel condition. We present additional detailed topographic anatomy of DCIA and its variation that can be used intraoperative guide to harvest the flap and teaching purpose. Standard DSA delivers valuable preoperative data regarding stenosis in addition to the topographic anatomy of the flap pedicle. However, imaging of the distal parts of the DCIA, nourishing the skin paddle is limited by the detector field used. For a full imaging of both DCIAs from the origin to the perforators, the intraarterial injection of contrast medium, as applied in DSA, could be combined with different imaging modalities like CT-angiography.

Longitudinal real world correlation study of blood pressure and novel features of cerebral magnetic resonance angiography by artificial intelligence analysis on elderly cognitive impairment.

This study aims to investigate novel clinical risk factors for cognitive impairment (CI) in elderly. A total of 3221 patients (259 patients with CI and 2,962 subjects without CI) were recruited into this nested case-control study who underwent cerebral magnetic resonance angiography (MRA) from 2007 to 2021. All of the clinical data with MRA imaging were recorded followed by standardization processing blindly. The maximum stenosis score of the posterior circulatory artery, including the basilar artery, and bilateral posterior cerebral artery (PCA), was calculated by the cerebral MRA automatic quantitative analysis method. Logistic regression (LR) analysis was used to evaluate the relationship between risk factors and CI. Four machine learning approaches, including LR, decision tree (DT), random forest (RF), and support vector machine (SVM), employing 5-fold cross-validation were used to establish CI predictive models. After matching with age and gender, 208 CI patients and 208 control subjects were finalized the follow-up (3.46 ± 3.19 years) with mean age at 84.47 ± 6.50 years old. Pulse pressure (PP) in first tertile (<58 mmHg) (OR 0.588, 95% confidence interval (CI): 0.362-0.955) was associated with a decreased risk for CI, and ≥50% stenosis of the left PCA (OR 2.854, 95% CI: 1.387-5.872) was associated with an increased risk for CI after adjusting for body mass index, myocardial infarction, and stroke history. Based on the means of various blood pressure (BP) parameters, the performance of the LR, DT, RF and SVM models accurately predicted CI (AUC 0.740, 0.786, 0.762, and 0.753, respectively) after adding the stenosis score of posterior circulatory artery. Elderly with low pulse differential pressure may have lower risk for cognitive impairment. The hybrid model combined with the stenosis score of posterior circulatory artery, clinical indicators, and the means of various BP parameters can effectively predict the risk of CI in elderly individuals.

Constructing Multiwavelet-based Shearlets and using Them for Automatic Segmentation of Noisy Brain Images Affected by COVID-19.

Nowadays, everybody's life is dominated by COVID-19, which might have been the source of severe acute respiratory syndrome coronavirus 2. This virus disrupts the lungs first of all. Recently, it has been found that coronavirus may affect the brain. Because all body actions rely on the brain, hence investigating its healthy is an essential item in coronavirus effects. Brain image segmentation can be helpful in the detection of the regions damaged by the effects of coronavirus. Since every image given by photography devices may have noises, therefore, first of all, the brain magnetic resonance angiography (MRA) images must be denoised for best investigation. In the present paper, we have presented the construction of multishearlets based on multiwavelets for the first time and have used them for the purpose of denoising. Multiwavelets have some advantages to wavelets. Therefore, we have used them in the shearlet system to expand the properties of multiwavelets in all directions. After denoising, we have proposed a scheme for the automatic characterization of the initial curve in the active contour model for segmentation. Detecting the initial curve is a challenging task in active contour-based segmentation because detecting an initial curve far from the desired region can lead to unfavorable results. The results show the performance of using multishearlets in detecting affected regions by COVID-19. Using multishearlets has led to the high value of peak signal-to-noise ratio and Structural similarity index measure in comparison with original shearlets. Original shearlets are constructed from wavelets whereas we have constructed multishearlets from multiwavelets. The results show that multishearlets can neutralize the effect of noise in MRA images in a good way rather than shearlets. Moreover, the proposed scheme for segmentation can lead to 0.99 accuracy.

Abstract WMP83: Arterial Dissection: A Still Underestimated Cause Of Lateral Medullary Infarction

Introduction: Although the association between vertebral artery or posterior inferior cerebellar artery dissection and lateral medullary infarction (LMI) has been established, the actual prevalence of dissection among patients with LMI may still be underestimated. Methods: Consecutive patients with acute pure LMI admitted between 2010 and 2021 were included. High-resolution vessel wall MRI (VWMRI) and/or transfemoral cerebral angiography (TFCA) were performed in a part of patients and were regarded as gold standard tests for diagnosis of dissection. Factors associated with definite dissection based on VWMRI or TFCA findings were assessed. Risk scoring for dissection was created based on multivariate logistic regression and applied to estimate the number of possible dissection. Results: Eighty-seven LMI patients were eligible and 47 (54.0%) of them underwent VWMRI (n=43) and/or TFCA (n=7). Among these 47 cases, 24 were definite dissection. Three out of 40 patients without gold standard tests were diagnosed with definite dissection based on conventional MRI findings. Preceding headache and normal body weight were independently associated with dissection in LMI patients. A risk scoring which includes age, body mass index, and headache predicted dissection with 91.7% sensitivity and 69.6% specificity (area under the receiver operating characteristic curve, 0.889; 95% confidence intervals, 0.802-0.977) in our population. Additional nine out of 37 patients without gold standard tests nor diagnosis of definite dissection in conventional MRI could be considered as possible dissection based on the scoring. Definite and possible dissections together comprised 41.4% (n=36) of LMI in our study. Conclusions: Arterial dissection may be more prevalent among LMI patients than reported before. Thorough diagnostic effort for dissection is necessary based on scrutinizing risk stratification.

Automated unruptured cerebral aneurysms detection in TOF MR angiography images using dual-channel SE-3D UNet: a multi-center research.

Time of flight magnetic resonance angiography (TOF-MRA) is the primary non-invasive screening method for cerebral aneurysms. We aimed to develop a computer-aided aneurysm detection method to improve the diagnostic efficiency and accuracy, especially decrease the false positive rate. This is a retrospective multicenter study. The dataset contained 1160 TOF-MRA examinations composed of unruptured aneurysms (n = 1096) and normal controls (n = 166) from six hospitals. A total of 1037 examinations acquired from 2013 to 2019 were used as training set; 123 examinations acquired from 2020 to 2021 were used as external test set. We proposed an equalized augmentation strategy based on aneurysm location and constructed a detection model based on dual channel SE-3D UNet. The model was trained with a 5-fold cross-validation in the training set, then tested on the external test set. The proposed method achieved 82.46% sensitivity on patient-level, 73.85% sensitivity on lesion-level, and 0.88 false positives per case in the external test set. The performance did not show significant differences in subgroups according to the aneurysm site (except ACA), aneurysm size (except smaller than 3 mm), or MRI scanners. The performance preceded the basic SE-3D UNet by increasing 15.79% patient-level sensitivity and decreasing 4.19 FPs/case. The proposed automated aneurysm detection method achieved acceptable sensitivity while controlling fairly low false positives per case. It might provide a useful auxiliary tool of cerebral aneurysms MRA screening. • The need for automated cerebral aneurysms detecting is growing. • The strategy of equalized augmentation based on aneurysm location and dual-channel input could improve the model performance. • The retrospective multi-center study showed that the proposed automated cerebral aneurysms detection using dual-channel SE-3D UNet could achieve acceptable sensitivity while controlling a low false positive rate.

Customizable tubular model for n-furcating blood vessels and its application to 3D reconstruction of the cerebrovascular system

Understanding the 3D cerebral vascular network is one of the pressing issues impacting the diagnostics of various systemic disorders and is helpful in clinical therapeutic strategies. Unfortunately, the existing software in the radiological workstation does not meet the expectations of radiologists who require a computerized system for detailed, quantitative analysis of the human cerebrovascular system in 3D and a standardized geometric description of its components. In this study, we show a method that uses 3D image data from magnetic resonance imaging with contrast to create a geometrical reconstruction of the vessels and a parametric description of the reconstructed segments of the vessels. First, the method isolates the vascular system using controlled morphological growing and performs skeleton extraction and optimization. Then, around the optimized skeleton branches, it creates tubular objects optimized for quality and accuracy of matching with the originally isolated vascular data. Finally, it optimizes the joints on n-furcating vessel segments. As a result, the algorithm gives a complete description of shape, position in space, position relative to other segments, and other anatomical structures of each cerebrovascular system segment. Our method is highly customizable and in principle allows reconstructing vascular structures from any 2D or 3D data. The algorithm solves shortcomings of currently available methods including failures to reconstruct the vessel mesh in the proximity of junctions and is free of mesh collisions in high curvature vessels. It also introduces a number of optimizations in the vessel skeletonization leading to a more smooth and more accurate model of the vessel network. We have tested the method on 20 datasets from the public magnetic resonance angiography image database and show that the method allows for repeatable and robust segmentation of the vessel network and allows to compute vascular lateralization indices.Graphical abstract

Coregistered transcranial optoacoustic and magnetic resonance angiography of the human brain.

Imaging modalities capable of visualizing the human brain have led to major advances in neurology and brain research. Multi-spectral optoacoustic tomography (MSOT) has gained importance for studying cerebral function in rodent models due to its unique capability to map changes in multiple hemodynamic parameters and to directly visualize neural activity within the brain. The technique further provides molecular imaging capabilities that can facilitate early disease diagnosis and treatment monitoring. However, transcranial imaging of the human brain is hampered by acoustic attenuation and other distortions introduced by the skull. Here, we demonstrate non-invasive transcranial MSOT angiography of pial veins through the temporal bone of an adult healthy volunteer. Time-of-flight (TOF) magnetic resonance angiography (MRA) and T1-weighted structural magnetic resonance imaging (MRI) were further acquired to facilitate anatomical registration and interpretation. The superior middle cerebral vein in the temporal cortex was identified in the MSOT images, matching its location observed in the TOF-MRA images. These initial results pave the way toward the application of MSOT in clinical brain imaging.

Correlation between unilateral internal carotid artery stenosis and asymmetric distribution of enlarged perivascular spaces in patients with acute cerebral infarction

Objective: To explore the correlation between unilateral internal carotid artery (ICA) stenosis and asymmetrical distribution of enlarged perivascular spaces (EPVS) in patients with acute cerebral infarction. Methods: Acute cerebral infarction patients with unilateral ICA stenosis hospitalized in Changzhou Second People's Hospital from October 2020 to December 2021 were collected. Routine cranial MRI and CT angiography were completed for each patient. The 3D Slicer software was used to quantitatively analyze the volume of patient's EPVS. Patients were divided into moderate stenosis group and severe stenosis/occlusion group according to the degree of ICA stenosis. Baseline data were compared between the two groups. Patients were further divided into three groups: moderate stenosis, severe stenosis and occlusion groups, and the ipsilateral and contralateral EPVS volume of ICA stenosis patients was compared. The asymmetry index (AI) was calculated for EPVS in the basal ganglia region (BG-EPVS) and EPVS in the centrum semiovale (CSO-EPVS). Patients with AI≥0.2 were included in the EPVS asymmetry group, while the rest were in the EPVS symmetry group, and the degree of unilateral ICA stenosis was compared between the two groups. Multivariate logistic regression model was used to analyze the relationship between ICA severe stenosis/occlusion and the asymmetric distribution of BG-EPVS. Results: A total of 122 patients (96 males and 26 females) were enrolled, aged (70±10) years, with 81 cases in the unilateral ICA severe stenosis/occlusion group (46 cases of severe stenosis and 35 of occlusion) and 41 cases in the moderate stenosis group. Patients in the unilateral ICA severe stenosis/occlusion group had greater BG-EPVS volume [(4.08±0.76) mm3]and proportion of asymmetric distribution of BG-EPVS [75.3%(61/81)] than those of the moderate stenosis group [(3.12±0.85) mm3 and 39.0% (16/41)], with statistically significant differences (both P<0.001). The BG-EPVS volumes of the ipsilateral side of the stenosis in the severe stenosis group and the occlusion group [(3.34±0.86) mm3 and (3.93±0.60) mm3] were significantly greater than those of the contralateral side [(2.65±1.28) mm3 and (3.21±0.88) mm3], with statistically significant differences (both P<0.001). Correlation analysis indicated that the degree of unilateral ICA stenosis was positively correlated with the BG-EPVS volume on the stenosis side (r=0.62, P<0.001). Further comparison of the degree of unilateral ICA stenosis between the EPVS symmetric and asymmetric groups showed that the proportion of unilateral ICA severe stenosis/occlusion in the BG-EPVS asymmetry group was higher than that in the symmetric group [79.2%(61/77) vs 44.4%(20/45),P<0.001]. Multivariate logistic regression analysis showed that unilateral ICA severe stenosis/occlusion (OR=4.280, 95%CI: 1.743-10.508, P =0.002) and age (OR=1.055, 95%CI: 1.001-1.112, P=0.044) were risk factors for asymmetric distribution of BG-EPVS. Conclusions: The severe stenosis/occlusion of the unilateral ICA and age are the risk factors for the asymmetric distribution of the BG-EPVS in patients with acute cerebral infarction. The ipsilateral EPVS volume of unilateral ICA stenosis is larger than that of the contralateral side, and the degree of ICA stenosis is positively correlated with the severity of BG-EPVS.

Vasospastic angina following COVID-19 vaccine-related myocarditis: an underlying cause of chest pain.

We present a 13-year-old boy who had recurrent chest pain with elevated cardiac enzymes and abnormal ST segments in electrocardiogram 36 hours after the second dose of BNT162b2 vaccination. Cardiac MRI and coronary angiography with acetylcholine provocation confirmed myocarditis and vasospastic angina, respectively. Coronary vasospasm may play a pivotal role in the chest pain in COVID-19 vaccine-related myocarditis.

Moyamoya syndrome in Schimke immuno-osseous dysplasia

Introduction. Schimke immuno-osseous dysplasia (SIOD) is a rare autosomal recessive multisystem disorder associated with biallelic mutations of the SMAR-CAL1 gene. Vascular central nervous system complications in the form of Moyamoya syndrome (MMS) have been reported as a comorbidity in nearly half of the patients clinically presenting with severe migraine-like headaches, transient ischemic attacks (TIA), and ischemic or hemorrhagic infarctions. We present an illustrative case of an infantile form of SIOD with MMS, with a review of the latest diagnostic possibilities, as well as current diagnostic and therapeutic dilemmas in managing SIOD. Case report. We present a female patient with the infantile form of SIOD. The proband was born small for gestational age in the 34th gestation week with characteristic dysmorphic features. Genetic testing found a biallelic, nonsense mutation c.2542G&gt;T in the SMARCAL1 gene. The patient presented early with TIA, seizures, and recurrent ischemic strokes. Magnetic resonance imaging (MRI) confirmed the presence of progressive brain atrophy with bilateral occlusion/stenosis of middle cerebral artery and anterior cerebral artery and a smoke-like collateral vessel appearance consistent with the MMS. At the age of 5 years and 9 months, the patient developed a high fever and cough with unknown cause, with a low erythrocyte and white blood cell count during four weeks, with a poor therapeutic response to antibiotics, transfusion of red blood cells, and granulocyte growth factor. She later died. Conclusion. Patients with SIOD may present progressive cerebral vascular changes and clinical neurologic deterioration early in the course of the disease. In such patients, early diagnosis and preventive revascularization surgery are of paramount importance. In diagnosing MMS, MRI angiography can be an appropriate substitute for standard invasive cerebral angiography.

Non-contrast magnetic resonance angiography for systemic artery evaluation in Kawasaki disease.

Kawasaki disease (KD) is a systemic vasculitis; systemic arteries other than the coronary arteries should therefore also be evaluated. This study investigated the feasibility of evaluating coronary aneurysms, systemic artery aneurysms (SAAs), and cerebrovascular diseases in patients with KD using non-contrast magnetic resonance angiography (NC-MRA). Coronary artery protocols, including coronary magnetic resonance angiography (MRA) and vessel wall imaging, were performed in 57 examinations of 28 patients. Systemic artery protocol, including SAA scans and head MRA, along with coronary artery protocol, were performed in 42 examinations of 42 patients. The image quality of the SAAs was evaluated on a 4-point scale. Examination time and sedation dosage were compared between the protocols. The presence of SAAs and cerebrovascular disease was also evaluated. The image quality score of SAAs was 4 (interquartile range [IQR]: 4-4) for the aorta, 4 (IQR: 3-4) for the subclavian artery, 4 (IQR: 3-4) for the renal artery, and 3 (IQR: 3-4) for the iliac artery. No differences were found between examination time (47.0 [IQR: 43.0-61.0] min vs. 51.0 [IQR: 45.0-60.0] min, p = 0.48) and sedative dose (4.63 [IQR: 3.93-5.79] mg/kg vs. 4.21 [IQR: 3.56-5.71] mg/kg, p = 0.37) between the protocols. Systemic artery protocol detected SAAs in three patients (7.1%), and cerebrovascular disease was not detected. Evaluating the coronary and systemic arteries in patients with KD using NC-MRA on a single examination was possible without compromising examination time or sedation dose. The systemic artery protocol was useful in finding SAAs.