Magnetic Resonance Imaging Angiography Research Articles

Сapabilities of Dynamic Infrared Thermography for Planning and Monitoring of Perforating Flaps

Background. Free perforating flaps are the most optimal for reconstruction of both upper and lower extremities. However, along with the obvious advantages of these flaps, there are also a number of difficulties associated with their more complex vascular anatomy and, as a consequence, more time-consuming dissection. This determines the need for a more thorough preoperative planning, including the mapping of perforating vessels and development of flap design. At the same time, the problems with intraoperative assessment of perfusion of perforating flaps and their monitoring in the postoperative period have not been solved. For these purposes, several instrumental methods of examination such as MRI and CT angiography, Doppler sonography, ICG and dynamic infrared thermography are used.
 Aim of the study — to evaluate the capabilities of dynamic infrared thermography (DIT) for mapping of perforating vessels when planning the design of perforating flaps, as well as for assessing their intra- and postoperative perfusion.
 Methods. We have analyzed the results of using DIT along with CT-angiography and Doppler sonography for preliminary mapping of perforating vessels in the design of 18 perforating flaps (ALT flap — 10, SCIP flap — 8) transplanted in 15 patients from 01.01.2022 to 30.07.2022. DIT was also used in all cases for intraoperative instrumental confirmation of flap perfusion and for its monitoring in the postoperative period.
 Results. A total of 39 perforating vessels were detected by CT angiography at the point of origin from the main arteries. DIT was used to detect the distal portions of 37 perforating vessels in 15 patients at the marking of 18 flaps. On average, 2.5 per ALT flap and 1.4 per SCIP flap. Thermographic examination time was approximately 10 minutes. Localization of all perforating vessels detected by DIT were first confirmed by Doppler sonography and then visualized intraoperatively during flap dissection. Intraoperatively, perfusion of all transplanted flaps was clearly confirmed by DIT. In the postoperative period, perfusion problems were clinically detected in 3 (16%) flaps and confirmed by DIT: venous stasis — 2 cases, arterial insufficiency — 1 case. In two patients (13%) with a body mass index of more than 35 (corresponding to class 2–3 obesity), the location of perforating vessels could not be determined by thermography and Doppler sonography. Also, in these patients DIT was ineffective for confirmation of flap perfusion intraoperatively and in the postoperative period.
 Conclusion. This study confirms that CT angiography, Doppler sonography and infrared thermography are complementary methods that allow to detect and visualize perforating arteries from their origin from a main artery to the site of their passage through the deep fascia (CT-angiography), as well as to determine their more accurate projection on the skin surface (DIT and Doppler sonography). DIT is also an auxiliary method for flap monitoring in the intraoperative and postoperative periods, which allows to engage nursing staff in postoperative monitoring.

Deep learning-based 3D cerebrovascular segmentation workflow on bright and black blood sequences magnetic resonance angiography

BackgroundCerebrovascular diseases have emerged as significant threats to human life and health. Effectively segmenting brain blood vessels has become a crucial scientific challenge. We aimed to develop a fully automated deep learning workflow that achieves accurate 3D segmentation of cerebral blood vessels by incorporating classic convolutional neural networks (CNNs) and transformer models.MethodsWe used a public cerebrovascular segmentation dataset (CSD) containing 45 volumes of 1.5 T time-of-flight magnetic resonance angiography images. We collected data from another private middle cerebral artery (MCA) with lenticulostriate artery (LSA) segmentation dataset (MLD), which encompassed 3.0 T three-dimensional T1-weighted sequences of volumetric isotropic turbo spin echo acquisition MRI images of 107 patients aged 62 ± 11 years (42 females). The workflow includes data analysis, preprocessing, augmentation, model training with validation, and postprocessing techniques. Brain vessels were segmented using the U-Net, V-Net, UNETR, and SwinUNETR models. The model performances were evaluated using the dice similarity coefficient (DSC), average surface distance (ASD), precision (PRE), sensitivity (SEN), and specificity (SPE).ResultsDuring 4-fold cross-validation, SwinUNETR obtained the highest DSC in each fold. On the CSD test set, SwinUNETR achieved the best DSC (0.853), PRE (0.848), SEN (0.860), and SPE (0.9996), while V-Net achieved the best ASD (0.99). On the MLD test set, SwinUNETR demonstrated good MCA segmentation performance and had the best DSC, ASD, PRE, and SPE for segmenting the LSA.ConclusionsThe workflow demonstrated excellent performance on different sequences of MRI images for vessels of varying sizes. This method allows doctors to visualize cerebrovascular structures.Critical relevance statementA deep learning-based 3D cerebrovascular segmentation workflow is feasible and promising for visualizing cerebrovascular structures and monitoring cerebral small vessels, such as lenticulostriate arteries.Key points• The proposed deep learning-based workflow performs well in cerebrovascular segmentation tasks.• Among comparison models, SwinUNETR achieved the best DSC, ASD, PRE, and SPE values in lenticulostriate artery segmentation.• The proposed workflow can be used for different MR sequences, such as bright and black blood imaging.Graphical

Cerebrovascular disease in patients with antiphospholipid antibody syndrome: a transcranial Doppler and magnetic resonance imaging study.

Transcranial Doppler (TCD) and brain MRI may be useful in evaluating patients with APS, helping to stratify the risk of cerebrovascular ischaemic events in this population. This study aimed to assess the frequency of brain MRI abnormalities in patients with primary antiphospholipid syndrome, secondary antiphospholipid syndrome and SLE and correlate to TCD findings. The study, conducted over four years at two autoimmune disease referral centres, included 22 primary antiphospholipid syndrome patients, 24 secondary antiphospholipid syndrome patients, 27 SLE patients without APS and 21 healthy controls. All participants underwent TCD to assess cerebral haemodynamics, detect microembolic signals and evaluate right-to-left shunts, followed by brain MRI and magnetic resonance angiography. MRI scans were reviewed for acute microembolism, localized cortical infarctions, border infarctions, lacunar infarctions, ischaemic lesions, white matter hyperintensity, micro and macro haemorrhages and arterial stenosis ≥50% of the cervical carotid artery, by two neuroradiologists blinded to the clinical data. Brain MRI findings were similar between the groups, except for lacunar infarction, more frequent in patients with secondary antiphospholipid syndrome (P = 0.022). Patients with intracranial stenosis detected by TCD had a higher frequency of territorial infarction (40% vs 7.5%, P = 0.02), lacunar (40% vs 11.3%, P = 0.075) and border zone infarcts (20% vs 1.9%, P = 0.034). Patients with intracranial stenosis presented a higher frequency of territorial, lacunar and border zone infarcts, suggesting that evaluating the intracranial vasculature should not be neglected in patients with APS and stroke.

Detection of femoropopliteal arterial steno-occlusion at MR angiography: initial experience with artificial intelligence

BackgroundThis study evaluated a deep learning (DL) algorithm for detecting vessel steno-occlusions in patients with peripheral arterial disease (PAD). It utilised a private dataset, which was acquired and annotated by the authors through their institution and subsequently validated by two blinded readers.MethodsA single-centre retrospective study analysed 105 magnetic resonance angiography (MRA) images using an EfficientNet B0 DL model. Initially, inter-reader variability was assessed using the complete dataset. For a subset of these images (29 from the left side and 35 from the right side) where digital subtraction angiography (DSA) data was available as the ground truth, the model’s accuracy and the area under the curve at receiver operating characteristics analysis (ROC-AUC) were evaluated.ResultsA total of 105 patient examinations (mean age, 75 years ±12 [mean ± standard deviation], 61 men) were evaluated. Radiologist-DL model agreement had a quadratic weighted Cohen κ ≥ 0.72 (left side) and ≥ 0.66 (right side). Radiologist inter-reader agreement was ≥ 0.90 (left side) and ≥ 0.87 (right side). The DL model achieved a 0.897 accuracy and a 0.913 ROC-AUC (left side) and 0.743 and 0.830 (right side). Radiologists achieved 0.931 and 0.862 accuracies, with 0.930 and 0.861 ROC-AUCs (left side), and 0.800 and 0.799 accuracies, with 0.771 ROC-AUCs (right side).ConclusionThe DL model provided valid results in identifying arterial steno-occlusion in the superficial femoral and popliteal arteries on MRA among PAD patients. However, it did not reach the inter-reader agreement of two radiologists.Relevance statementThe tested DL model is a promising tool for assisting in the detection of arterial steno-occlusion in patients with PAD, but further optimisation is necessary to provide radiologists with useful support in their daily routine diagnostics.Key points• This study focused on the application of DL for arterial steno-occlusion detection in lower extremities on MRA.• A previously developed DL model was tested for accuracy and inter-reader agreement.• While the model showed promising results, it does not yet replace human expertise in detecting arterial steno-occlusion on MRA.Graphical

A New Preoperative Simulation Using Magnetic Resonance Imaging Bone-Like Imaging with Zero-Echo-Time Sequence

This study aimed to evaluate the clinical usefulness of zero-echo time(ZTE)-based magnetic resonance imaging(MRI)in planning an optimal surgical approach and applying ZTE for anatomical guidance during transcranial surgery. P atients who underwent transcranial surgery and carotid endarterectomy and for whom ZTE-based MRI and magnetic resonance angiography(MRA)data were obtained, were analyzed by creating ZTE/MRA fusion images and 3D-ZTE-based MRI models. We examined whether these images and models could be substituted for computed tomography imaging during neurosurgical procedures. Furthermore, the clinical usability of the 3D-ZTE-based MRI model was evaluated by comparing it with actual surgical views. ZTE/MRA fusion images and 3D-ZTE-based MRI models clearly illustrated the cranial and intracranial morphology without radiation exposure or the use of an iodinated contrast medium. The models allowed the determination of the optimum surgical approach for cerebral aneurysms, brain tumors near the brain surface, and cervical internal carotid artery stenosis by visualizing the relationship between the lesions and adjacent bone structures. However, ZTE-based MRI did not provide useful information for surgery for skull base lesions, such as vestibular schwannoma, because bone structures of the skull base often include air components, which cause signal disturbances in MRI. ZTE sequences on MRI allowed distinct visualization of not only the bone but also the vital structures around the lesion. This technology is minimally invasive and useful for preoperative planning and guidance of the optimum approach during surgery in a subset of neurosurgical diseases.

New Vessel Extraction Method by Using Skew Normal Distribution for MRA Images

Vascular-related diseases pose significant public health challenges and are a leading cause of mortality and disability. Understanding the complex structure of the vascular system and its processes is crucial for addressing these issues. Recent advancements in medical imaging technology have enabled the generation of high-resolution 3D images of vascular structures, leading to a diverse array of methods for vascular extraction. While previous research has often assumed a normal distribution of image data, this paper introduces a novel vessel extraction method that utilizes the skew normal distribution for more accurate probability distribution modeling. The proposed method begins with a preprocessing step to enhance vessel structures and reduce noise in Magnetic Resonance Angiography (MRA) images. The skew normal distribution, known for its ability to model skewed data, is then employed to characterize the intensity distribution of vessels. By estimating the parameters of the skew normal distribution using the Expectation-Maximization (EM) algorithm, the method effectively separates vessel pixels from the background and non-vessel regions. To extract vessels, a thresholding technique is applied based on the estimated skew normal distribution parameters. This segmentation process enables accurate vessel extraction, particularly in detecting thin vessels and enhancing the delineation of vascular edges with low contrast. Experimental evaluations on a diverse set of MRA images demonstrate the superior performance of the proposed method compared to previous approaches in terms of accuracy and computational efficiency. The presented vessel extraction method holds promise for improving the diagnosis and treatment of vascular-related diseases. By leveraging the skew normal distribution, it provides accurate and efficient vessel segmentation, contributing to the advancement of vascular imaging in the field of medical image analysis.

Superior mesenteric artery revisited using magnetic resonance angiography.

We aimed to examine the superior mesenteric artery in detail by magnetic resonance angiography to provide an alternative to other imaging methods, to reduce the exposure time of patients and physicians to X-rays and the time spent in catheter angiography, to determine the variations, positions, and locations of the celiac trunk, and to provide detailed information for surgeons and interventional radiologists using this method. The procedures were approved by the Kocaeli University Medical School Non-Interventional Clinical Research Ethics Committee (10.04.2023, approval number: 2021/51). MR angiography images of 185 patients with abdominal imaging in PACS (Picture Archiving Communication Systems) were retrospectively registered. The level of origin of the superior mesenteric artery according to the vertebral column, angle of origin, distance between the superior mesenteric artery and branches of the abdominal aorta, and branching pattern of the superior mesenteric artery were evaluated. Parameters were evaluated according to gender and age using SPSS version 25. The distance between superior mesenteric artery-inferior mesenteric artery and superior mesenteric artery-aortic bifurcation in males was higher than in females, and the difference was statistically significant. In females and the whole study group, a low, positive and significant relationship was found between age and superior mesenteric artery-sagittal angle. The most common origin site for the superior mesenteric artery, according to the vertebral column was found to be at L1 middle for males and L1 upper for females. The most common superior mesenteric artery branching pattern was classical type in both genders. Individual evaluation of the superior mesenteric artery could reduce the risks during surgical interventions, considering the relationship of the superior mesenteric artery, especially with distally located vessels, and the gender differences for the angle of origin. Furthermore, considering that interventional radiologists choose the catheter according to the angle of origin of the artery during catheter angiography procedures, individual evaluation of patients taking into account gender and age is of utmost importance.

Transient ischemic attack in the vertebrobasilar vascular territory as a cause of isolated vertigo

Transient ischemic attack (TIA) in the vertebrobasilar vascular territory (VB) causes difficulties in diagnosis when it manifests only with vestibular symptoms. Issues relating to the differential diagnosis of TIA are discussed, awareness of which is necessary for the selection of informative methods of examination and the prescription of effective stroke prevention in patients with an episode of isolated dizziness. The likelihood of TIA as the cause of dizziness is increased by the patients' high cardiovascular risk, the presence of atrial fibrillation, severe instability during an attack, and head and/or neck pain. If a TIA in VB is suspected, it is advisable to perform a minimal instrumental examination, including computed tomography (CT) of the brain and CT angiography or diffusion-weighted magnetic resonance imaging (MRI) and MRI angiography. In case of doubt, additional information can be obtained by a perfusion CT or MRI as well as a post-contrast MRI. When interpreting the results of these methods of examination, their limitations in terms of application time and resolution should be taken into account.

Staged cluster transformers for intracranial aneurysms segmentation from structure fused 3D MRA

AbstractIntracranial aneurysms (IAs) manifest as atypical dilatation within the intracranial arterial structures, the rupture of which accounts for high mortality and morbidity rates. Current clinical protocols require radiologists to manually annotate IAs on Magnetic Resonance Angiography (MRA) images, which is inherently subjective and time‐consuming. Given these limitations, there is an urgent need to explore methods for automated and accurate segmentation of IAs from MRA images. In particular, recent years have witnessed the proliferation of sophisticated computational techniques, with deep learning algorithms—especially the 3D U‐Net and its derivatives—gaining prominence in segmentation works. Nevertheless, convolutional neural network (CNN)‐based models have an inherent limitation in capturing long‐range spatial dependencies, which inadvertently compromises the retention of global features critical for segmentation. In response to this challenge, we introduce an avant‐garde architectural design, dubbed staged cluster transformers (SCTR), which incorporates cluster mechanism into vision transformers to perform volumetric MRA image segmentation. In addition to the MRA clustering branch, the spatially aligned brain Magnetic Resonance Imaging (MRI) representation branch is also combined to extract the structural features and assist the network in learning richer contextual and boundary information for accurate voxel prediction. For validation, we utilized both a publicly available challenge dataset and an internal clinical dataset in this study. Our proposed model achieves dice similarity coefficients (DSC) of 0.5587 and 0.8110 on these two datasets, respectively, outperforming other state‐of‐the‐art approaches. The results suggest that SCTR is a promising method for automatic segmentation of IAs. Our code is available at https://github.com/guolilin/SCTR.

Bilateral Ocular Ischaemic Syndrome due to Carotid Artery and Cardiovascular Disease: A Case Report

Introduction : Ocular ischemic syndrome (OIS) is a rare but potentially blinding and fatal condition caused by carotid artery disease or other systemic condition results in ocular hypoperfusion.
 Case Illustration : A 62-year-old male with sudden bilateral vision loss, swelling, redness and pain of both eye for 7 days. There were dilated conjunctival and episcleral vessels, visual acuity of the right eye was hand movement and 0.05 for left eye, intraocular pressure (IOP) was 33 mmHg in right eye and 37 mmHgfor left eye. Anterior segment evaluation revealed rubeosis iris, mild anterior chamber reaction, and temporal angle neovascularization on gonioscopy. Both direct and consensual light reflexes were sluggish. Fundus examination showed normal optic disc, minimal hemorrhages at mid-periphery, narrowed arterioles, and minimal cotton wool spot. Macular OCT demonstrated discrete hyperreflectivity of inner retinal layers. From Macular Angiography OCT, ETDRS Central vessel density were 11.2% and 17.6% for the right eye and left eye, respectively. In both eyes, paracentesisof anterior chamber, intravitreal and intracameral injections of anti-VEGF were performed. Brain Magnetic Resonance Angiography Imaging revealed moderate stenosis of both distal carotid artery circulation. Percutaneous Coronary Angiography showed extensive stenosis in coronary artery, with low Ejection Fraction.
 Discussion : For the cardiovascular management, a pacemaker was implanted. One week after procedure, BCVA were 1/60 and 0.15, and IOPs of 17 and 18 mmHg, for the right and left eye, respectively. The patient was scheduled to have laser retinal photocoagulation.
 Conclusion : Quick clinical diagnosis, targeted workup for systemic associations, and prompt treatment might preserve life and sight in OIS.

Visual manifestations in giant cell arteritis: identification of risk factors from the ARTESER Registry.

To determine the prevalence and predictive factors of visual manifestations in a large registry of patients with GCA. ARTESER is a large Spanish multicentre registry supported by the Spanish Society of Rheumatology. It includes patients with GCA from across the entire country diagnosed between June 2013 and March 2019. The variables collected at diagnosis were demographics, clinical manifestations (including all visual manifestations), laboratory, temporal artery biopsy, and imaging findings (ultrasound, FDG-PET/CT, MRI angiography, CT angiography). Patients with and without visual involvement were compared in a bivariate analysis. Multivariate logistic regression was performed to determine potential predictive factors of visual manifestations. The study population comprised 1636 GCA patients, of whom 599 (36.6%) presented visual manifestations. Anterior ischemic optic neuropathy was the most frequent (n = 274 of 599; 45.7%) ocular complication. The independent predictors that increased the risk (OR; 95% confidence interval) of visual involvement were older age (1.027; 1.009-1.045) and jaw claudication (1.724; 1.325-2.243). The variables associated with a reduced risk were polymyalgia rheumatica (0.541; 0.414-0.708), fever (0.373; 0.264-0.527), longer symptom duration (0.946; 0.909-0.985), and higher erythrocyte sedimentation rate (ESR) (0.992; 0.988-0.997), common features of patients with large vessel-GCA. One-third of GCA patients present visual manifestations at diagnosis. Older age and jaw claudication are independent predictors of visual manifestations, whereas polymyalgia rheumatica, fever, longer symptom duration, and high ESR reduce the risk of visual involvement.

Comparing flow and pulmonary artery growth post-patent ductus arteriosus stenting in patients with ductal-dependent pulmonary flow using 4D magnetic resonance imaging.

The 4D magnetic resonance imaging (4D-flow MRI) provides a qualitative and quantitative assessment of cardiovascular structures and processes. 4D-flow MRI was used to study pulmonary flow in post-patent ductus arteriosus (PDA) stent insertion in duct-dependent pulmonary flow neonates at baseline (PDA stent insertion) and after 6 months, and also, to evaluate the effect of flow dynamics on the growth of pulmonary arteries (PAs). This prospective observational study included neonates with ductus arteriosus-dependent pulmonary circulation who underwent ductal stenting between June 2021 and November 2022. Cardiac 4D-flow MRI and magnetic resonance angiography were conducted in two phases; after the deployment of the PDA stent during the neonatal period and after 6 months from stent deployment. Eight neonates were recruited, but only five completed both scans. A total of 10 PAs were evaluated during each phase. The median left PA (LPA) and right PA (RPA) diameters and indexed flow for LPA and RPA were evaluated. The growth rate of LPA was observed to be lower than that of RPA (percentage diameter increase: 74 vs. 153%). LPA Z-score was lower than RPA. Indexed flow in both LPA and RPA showed a reduction in the 6-month scan, which was consistent with reduced stent patency. 4D-flow cardiac MRI showed different growth rates and reduced flow between LPA and RPA post-PDA stent. These insights can aid in future management decisions.

Therapeutic small molecules in the development of treatment for subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a severe and often fatal condition characterized by the accumulation of blood beneath the arachnoid layer of the meninges. Predominantly affecting individuals in the 40–60 age range, it is commonly caused by head trauma from falls or car accidents. Ruptures of cerebral aneurysms also contribute significantly to SAH. Risk factors for SAH include hypertension and smoking, and symptoms typically include severe headache and neck pain. Diagnosing SAH typically involves a combination of medical history, physical examination, and imaging studies such as computed tomography angiography or magnetic resonance imaging angiography. Recent research suggests that pharmaceutical management of intracerebral hemorrhage (ICH) includes the administration of recombinant activated factor VII, tranexamic acid, and aggressive blood pressure reduction. For patients with significant SAH and ICH, minimally invasive surgical procedures for hematoma evacuation, as well as surgical evacuation of SAH and ICH, have proven to be highly beneficial. Furthermore, an emerging area of treatment involves therapeutic small molecules designed to interrupt the pathophysiological pathways leading to SAH. This novel approach holds promise for advancing our understanding and management of this complex medical condition.

3D Transcranial ultrasound localization microscopy reveals major arteries in the sheep brain.

Cerebral circulation ensures the proper functioning of the entire human body, and its interruption, i.e. stroke, leads to irreversible damage. However, tools for observing cerebral circulation are still lacking. Although MRI and CT scans serve as conventional methods, their accessibility remains a challenge, prompting exploration into alternative, portable, and non-ionizing imaging solutions like ultrasound with reduced costs. While Ultrasound Localization Microscopy (ULM) displays potential in high-resolution vessel imaging, its 2D constraints limit its emergency utility. This study delves into the feasibility of 3D ULM with multiplexed probe for transcranial vessel imaging in sheep brains, emulating human skull characteristics. Three sheep underwent 3D ULM imaging, compared with angiographic MRI, while skull characterization was conducted in vivo using ultrashort bone MRI sequences and ex vivo via micro CT. The study showcased 3D ULM's ability to highlight vessels, down to the Circle of Willis, yet within a confined 3D field-of-view. Future enhancements in signal, aberration correction, and human trials hold promise for a portable, volumetric, transcranial ultrasound angiography system.

Exploring the impact of super-resolution deep learning on MR angiography image quality.

The aim of this study is to assess the effect of super-resolution deep learning-based reconstruction (SR-DLR), which uses k-space properties, on image quality of intracranial time-of-flight (TOF) magnetic resonance angiography (MRA) at 3 T. This retrospective study involved 35 patients who underwent intracranial TOF-MRA using a 3-T MRI system with SR-DLR based on k-space properties in October and November 2022. We reconstructed MRA with SR-DLR (matrix = 1008 × 1008) and MRA without SR-DLR (matrix = 336 × 336). We measured the signal-to-noise ratio (SNR), contrast, and contrast-to-noise ratio (CNR) in the basilar artery (BA) and the anterior cerebral artery (ACA) and the sharpness of the posterior cerebral artery (PCA) using the slope of the signal intensity profile curve at the half-peak points. Two radiologists evaluated image noise, artifacts, contrast, sharpness, and overall image quality of the two image types using a 4-point scale. We compared quantitative and qualitative scores between images with and without SR-DLR using the Wilcoxon signed-rank test. The SNRs, contrasts, and CNRs were all significantly higher in images with SR-DLR than those without SR-DLR (p < 0.001). The slope was significantly greater in images with SR-DLR than those without SR-DLR (p < 0.001). The qualitative scores in MRAs with SR-DLR were all significantly higher than MRAs without SR-DLR (p < 0.001). SR-DLR with k-space properties can offer the benefits of increased spatial resolution without the associated drawbacks of longer scan times and reduced SNR and CNR in intracranial MRA.

Clinical Characteristics of Immediate Contralateral Ischemia Subsequent to Revascularization for Moyamoya Disease

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed. We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis. The mean age was 34.5 (range: 5-71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44-71years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF213 c.14429G > A variant were patchy and peripheral. Theother case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotidartery where patency had been confirmed preoperatively. Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types.

Debris generated by laser and/or balloon cause cerebral infarction with different severity.

The purpose of this study is to determine the effects that debris generated by laser and/or balloon on the brain. Debris generated by laser, balloon, and laser combined with balloon were collected and then injected into rats' left common carotid artery. Rats were divided into five groups: sham, saline, laser (L), balloon (B), and laser combined with balloon (LB). The cognition ability of rats was evaluated by Morris water maze. Cerebral blood flow (CBF) was examined by laser speckle. TTC staining and MRI scan were conducted to detect cerebral ischemic infarction. Intracranial arteries in rats were visualized by MRI angiography via contrast medium injected via tail vein. Immunohistologic staining for NeuN and Iba1 and hematoxylin-eosin staining were performed to assess brain infarction. White matter demyelination was assessed by Luxol fast blue staining. Long-term memory and CBF of rats in different groups exhibited no significant difference. No obstruction sign in intracranial artery tree was noticed in each group. Debris generated by different treatments all caused brain infarction. Infarction lesion caused by debris produced by balloon was much more severe than the one caused by debris generated by laser. While the LB group lay in between. The thickness of white matter decreased in the B group, but not in the L and LB groups. Rat brain has a tolerance for debris as cognition ability and cerebral blood flow are not significantly declined. The severity of cerebral infarction varies by debris generated by different treatments.

“Worse than hell”: Complex Neuraxial Lesions Resulting in Tetraplegia and Blindness after Polytrauma - Case presentation

Background. Lesions of the vertebral artery (VA) may develop spontaneously or as a result of severe traumatic cervico-cephalic injuries. Most frequent VA injuries (VAI) result from blunt trauma to the spine or may be due to penetrating lesions. VAI plays a significant role in the broader context of cervical spine trauma by providing insights into the vascular aspects of spinal cord injury (SCI). Upper cervical spine fractures and accompanying subluxation, as well as transverse process fractures extending into the artery bone foramen, are associated with an elevated risk of VAI. Clinical case. A 63-year-old female patient with flaccid C4 AIS-A quadriplegia (global motor score 3/100), vertebral myelopathy, neurogenic bladder, sacral pressure sore, and blindness was transferred from the spinal neurosurgical department. The patient fell from the same level and suffered a mild brain concussion and, apparently, a minor cervical SCI on October 1, 2022. She was asymptomatic, then quickly became tetraplegic, and then blindness added on in a few days. She was operated on on October 7, 2022, for a C6 vertebral body fracture and a C5-6 dislocation. The surgical protocol consisted of anterior spinal cord decompression, dislocation reduction, and mixed anterior fusion with bone grafts and fixation screws. Following the traumatic event, a bilateral posterior cerebral artery (PCA) stroke subsequently produced blindness and partial optic atrophy in both eyes. Serial clinical and imaging examinations confirmed the diagnosis: a subacute bilateral occipital stroke and a chronic lacunar lesion in the right thalamus associated with a severe spinal cord lesion. Anticoagulation has partially improved the neurological outcomes of stroke in the PCA territory. Ethical considerations. The patient's next of kin has given written consent to the case study and to use the radiological images related to the case for academic purposes. The personal identity data was anonymized. The presentation of this clinical case has the approval of the ethics commission of TEHBA (no. 40205/01.09.2023). Discussion. The clinical example is notable for the concurrent development of two severely devastating neurological syndromes, quadriplegia, and blindness, which occurred after an initially minor cervical trauma and progressed gradually over a few days. VA lesions after cervical trauma are considered rare, and the diagnosis is difficult because the vast majority of individuals do not exhibit cerebral neurological symptoms (due to the collateral compensatory blood supply from the circle of Willis). Most of the patients with bilateral or dominant VA occlusions are symptomatic, with rapid (and possibly fatal) ischemic damage to the encephalon, cerebellum, or brainstem. The detection and tracking of evolutionary tendencies required a series of clinical tests, including fundoscopy, and imaging procedures, including native CT, MRI, and MR angiography scans of the brain and spine. Conclusions. Although VAI is a rare complication, in every polytrauma patient with head and neck trauma, VA damage should be suspected. Careful clinical and imaging monitoring through detailed serial imaging procedures must be performed for every person with severe cranio-cervical trauma. The clinical example emphasizes the importance of the interprofessional team's participation in the patient's care.

Angiographic Evaluation of the Feeding Artery in Skull Base Meningioma.

To identify the characteristics of feeding arteries in skull base meningioma including location and prevalence, we evaluated the distributions and types of feeding arteries in skull base meningioma by cerebral angiography and assessed relationships to tumor attachment. We enrolled patients with skull base meningioma who underwent MRI and cerebral digital subtraction angiography (DSA), from September 2015 to October 2022. Subjects comprised 115 patients (32 males, 83 females; mean age, 52.7) with 117 meningiomas, showing tumor attachments around the "cavernous sinus to the upper part of the clivus" (Area 1), "lower part of the clivus to foramen magnum" (Area 2), and "tentorium around the petrous bone" (Area 3). Frequent arteries, such as the dorsal meningeal artery (DMA), the ascending pharyngeal artery (APA), the tentorial artery (TA), and the petrosal branch (PB) of the middle meningeal artery (MMA) were analyzed in terms of their associations with tumor attachment to Areas 1-3. Meningiomas with the DMA as a feeding artery correlated with tumor attachment to Area 1 (p < 0.001). Meningiomas with the APA correlated with tumor attachment to Area 2 (p < 0.001). Meningiomas with the TA correlated with tumor attachment to Area 3 (p < 0.001). The PB correlated with Area 3 (p < 0.05). Our study founded that visualization of these arteries correlated well with specific areas. These arteries were also the main feeders in each type of skull base meningioma.

Iliac endofibrosis in high-performance sports: an interdisciplinary diagnostic challenge

Iliac endofibrosis (IE) is a rare arterial disease in endurance athletes, especially cyclists and triathletes. The diagnosis is considered challenging and the latency from the onset of initial symptoms to diagnosis is often several years. Diagnostic options include determination of the ankle brachial index (ABI) after maximal exercise as a non-invasive procedure, as well as duplex sonography, CT or MRI angiography, and invasive angiography. The aim of this paper is to analyse in more detail this time lag to correct diagnosis from the first description in 1985 to the year 2021, as well as to identify the most important diagnostic tools for practice. Literature research according to PRISMA criteria in PubMed, Web of Science, Cochrane databases, supplemented by a search in Google Scholar up to 10/18/2021. We identified a total of 133 publications that dealt thematically with IE in endurance athletes. In 42 publications (40 case reports and 2 clinical trials), the diagnosis was confirmed intraoperatively, and in 32 (32/42; 74.4%), statements were made about the duration from the onset of the first symptoms to the final diagnosis (mean 45, median 36 months). This latency was constant over the entire observation period from 1985 to 2021, with no trend toward shortening. Twenty-four papers (24/42; 56%) reported detailed results of ABI determination as well as further diagnostic testing. In all cases, the ABI value decreased to less than 0.66 (in 5 case reports, this decrease was measured at rest; in 19 case reports, it occurred after stress), whereas further diagnostic testing by duplex sonography, DSA, MRA, or CTA revealed no abnormal findings in 3 cases (3/24; 12.5%) and showed no more than minor stenosis in 14 cases (14/24; 58.3%). A drop in ABI after exercise is the most reliable method to diagnose iliac endofibrosis. This non-invasive and easy-to-perform examination should be integrated into the performance diagnostics of highly ambitious endurance athletes at risk. This may ideally prevent irreversible vessel wall damage by early diagnosis as well as a reduction of the presumed high number of undetected cases.