Extracranial Vasculature Research Articles

Abstract 285: Intraventricular And Subarachnoid Hemorrhage Secondary To Arteriovenous Malformation, A Diagnostic Neurologic Manifestation Of Osler‐Weber‐Rendu Disease

Introduction Osler‐Weber‐Rendu disease, also known as hereditary hemorrhagic telangiectasia (HTT), is a developmental vascular disease characterized by multiple arteriovenous malformations (AVMs) due to genetic defects in endothelial angiogenesis pathways. HHT is a clinical diagnosis based on the fulfillment of the Curacao Diagnostic Criteria, including involvement of internal organs with AVMs, significant recurrent nosebleeds, telangiectasias, and family history of HHT. HHT has a prevalence of 1.5 to 2 people/10,000, although this is considered a falsely low representation due to missed diagnosis and variable penetrance. Autosomal dominantly inherited heterozygous mutations disrupt the TGF‐beta‐mediated pathways causing aberrant blood vessel development with fragility and AVM formation. There are two forms of HHT: (HHT1) has a higher incidence in women and typically involves pulmonary and cerebral arteriovenous malformations (AVM). Mutations in the endoglin gene are thought to be responsible for HTT1 and comprise approximately 61% of the cases. HTT2 is associated with a higher rate of liver AVMs, involves a mutation in Activin A Receptor‐Like Type 1 (ACVRL1), and is responsible for approximately 37% of cases. Other genetic mutations include SMAD4 and GDF2, which are transmitter and binding proteins and occur about 2% of the time. Methods Case report and review of literature Results Case:A 52‐year‐old woman with a large frontoparietal arteriovenous malformation originally found at the age of 17, with a history of frequent epistaxis, mucocutaneous telangiectasias and two children with epistaxis and telangiectasias. Her diagnosis of HHT was made at her third hjospitalization due to a non‐traumatic subarachnoid hemorrhage. A Chest CT angiography and a CT angiography of the intra and extracranial vasculature demonstrated an extensive right holohemispheric cerebral AVM, an unruptured 8‐mm basilar artery aneurysm, and multiple enlarged pulmonary arteries with narrow inlet and outlets concerning for pulmonary AVMs. A subsequent digital subtraction angiogram (DSA) of the brain confirmed the extensive holohemispheric AVM, unruptured basilar artery aneurism with subarachnoid hemorrhage originating from the AVM. On examination she had multiple lingual, and hard/soft palate telangiectasias and an extensive anterior pedal telangiectasia. Given the heavy cerebral AVM burden with multiple cerebral artery feeders, the AVM angiosclerosis and basilar artery aneurysm embolization were deferred. The patient proceeded under medical management alone with a plan for personal and familial genetic testing. Conclusion HHT is a rare cause of cerebral AVMs at high risk of spontaneous bleeding. Managing these AVMs can be a challenge, given the extent and location of these. However, diagnosis of HHT can inform prognosis and guide medical management due to improved prognosis for HHT‐related AVMs and aneurysms compared to non‐HHT AVMs.

Reversible Cerebral Vasoconstriction Syndrome associated to Cervical Artery Dissection: Two Cases and Review of the Literature. (P11-5.012)

<h3>Objective:</h3> The purpose of this study was to describe the association between Reversible Cerebral Vasoconstriction Syndrome (RCVS) and Cervical Artery Dissection (CAD) in two cases and to review the literature discussing potential explanations for the association. <h3>Background:</h3> RCVS and CAD are infrequent and potentially underdiagnosed pathological conditions. There are few case reports with simultaneous occurrence of both conditions. A potentially common underlying physiopathological mechanism is still unknown. <h3>Design/Methods:</h3> Retrospective study of consecutive cases of patients diagnosed with RCVS and/or CAD from January 2010 to June 2021 in a neurological institute in Buenos Aires, Argentina. Demographic, clinical, laboratory, and neuroimaging data were collected and reviewed. Possible predisposing factors, clinical course and treatment were also recorded. Literature review was performed using online search engine PubMed, until June 2021. <h3>Results:</h3> Seventy-three SVCR cases and 256 CAD cases were included. Only 2 patients had RCVS and CAD simultaneously. RCVS and CAD diagnosis in those two cases were made simultaneously. Both cases received treatment for CAD and RVCS and had good outcomes, without ischemic or hemorrhagic complications. These 2 cases add to 9 case reports and a case series of 20 patients published in the literature. <h3>Conclusions:</h3> The association between RCVS and CAD is infrequent and the pathophysiological mechanisms are still uncertain. Nonetheless, it is convenient to study intracranial and extracranial vasculature in all patients since the simultaneous diagnosis of these entities modifies the therapeutic plan and care. <b>Disclosure:</b> Dr. Ricciardi has nothing to disclose. Maia Gomez Schneider has nothing to disclose. Dr. Ruiz Yanzi has nothing to disclose. Mr. Garat has nothing to disclose. Dr. Alessandro has nothing to disclose. Dr. Dossi has nothing to disclose. Dr. Pujol Lereis has nothing to disclose. Dr. Ameriso has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for PHRI. Dr. Ameriso has received personal compensation in the range of $0-$499 for serving on a Speakers Bureau for Bayer, Boehringer, Abbott, AstraZeneca.

Brain Vasculature Color-Labeling Using the Triple-Injection Method in Cadaveric Heads: A Technical Note for Improved Teaching and Research in Neurovascular Anatomy.

Color-labeling injections of cadaveric heads have revolutionized education and teaching of neurovascular anatomy. Silicone-based and latex-based coloring techniques are currently used, but limitations exist because of the viscosity of solutions used. To describe a novel "triple-injection method" for cadaveric cranial vasculature and perform qualitative and semiquantitative evaluations of colored solution penetration into the vasculature. After catheter preparation, vessel cannulation, and water irrigation of embalmed cadaveric heads, food coloring, gelatin, and silicone solutions were injected in sequential order into bilateral internal carotid and vertebral arteries (red-colored) and internal jugular veins (blue-colored). In total, 6 triple-injected embalmed cadaveric heads and 4 silicone-based "control" embalmed cadaveric heads were prepared. A qualitative analysis was performed to compare the vessel coloring of 6 triple-injected heads with that of 4 "control" heads. A semiquantitative evaluation was completed to appraise sizes of the smallest color-filled vessels. Naked-eye and microscope evaluations of embalmed experimental and control cadaveric heads revealed higher intensity and more distal color-labeling following the "triple-injection method" compared with the silicone-based method in both the intracranial and extracranial vasculature. Microscope assessment of 1-mm-thick coronal slices of triple-injected brains demonstrated color-filling of distal vessels with minimum diameters of 119 μm for triple-injected heads and 773 μm for silicone-based injected heads. Our "triple-injection method" showed superior color-filling of small-sized vessels as compared with the silicone-based injection method, resulting in more distal penetration of smaller caliber vessels.

Retinal blood vessel analysis using optical coherence tomography in multiple sclerosis

Background: Both greater retinal neurodegenerative pathology and greater cardiovascular burden have been seen in persons with multiple sclerosis (pwMS).1,2 Moreover, studies have described multiple extracranial and intracranial vasculature changes in pwMS.3 However, only a few studies have examined the retinal vasculature in multiple sclerosis (MS).&#x0D; Objectives: To determine if there are differences in retinal vasculature between pwMS and healthy controls (HCs) and their relationship to peripapillary retinal nerve fiber layer (pRNFL) thickness.&#x0D; Materials and methods: A total of 167 pwMS (113 relapsing-remitting MS (RRMS) and 54 progressive MS (PMS)) and 48 HCs were scanned using optical coherence tomography (OCT). Earlier OCT scans were available in a smaller sample size of 101 pwMS and 35 HCs for additional longitudinal 5-year follow-up analysis. The semiautomated segmentation of the retinal vasculature was performed in a blinded manner on peripapillary scans using the optical coherence tomography segmentation and evaluation GUI (OCTSEG) in MatLab. (Figure 1). Automated segmentation of the pRNFL was performed in the native Heidelberg OCT software. The sum of bilateral measures of total retinal vessel diameter, the total number of retinal vessels and average vessel diameter were calculated. Independent sample t-test and paired t-test were used for cross-sectional and longitudinal analyses, respectively and non-parametric Spearman’s test for determining correlations.&#x0D; Results: PwMS had a significantly smaller total vessel diameter (2.5 cm vs 2.7 cm, age-adjusted p=0.017) and numerically fewer number of retinal vessels when compared to HCs (35.1 vs 36.8, age-adjusted p=0.167). No significant differences between the pwRRMS and pwPMS were found. Over the follow-up, pwMS had significant decrease in number of retinal vessels (36.7 vs. 33.0, p&lt;0.001) and significant increase in the average vessel diameter (0.072cm vs. 0.081cm, p&lt;0.001). No longitudinal changes in the HCs were noted. Only in pwMS, lower pRNFL was associated with fewer retinal vessels and total vessel diameter (r=0.191, p=0.018 and r=0.216, p=0.007).&#x0D; Conclusions: PwMS have retinal vasculature that results in smaller and fewer retinal vessels when compared to HCs that were related to reduced pRNFL. Over time, a reduction of retinal vasculature occurred. Future investigations should determine the relevance of retinal vasculature in regards to MS disease outcomes, presence of cardiovascular abnormalities and cerebral/retinal perfusion.

The role of cross-sectional imaging of the extracranial and intracranial vasculature in embolic stroke of undetermined source.

Despite an extensive workup, nearly one third of ischemic strokes are defined as Embolic Stroke of Undetermined Source (ESUS), indicating that no clear etiologic cause has been identified. Since large vessel atherosclerotic disease is a major cause of ischemic stroke, we focus on imaging of large vessel atherosclerosis to identify further sources of potential emboli which may be contributing to ESUS. For a stroke to be considered ESUS, both the extracranial and intracranial vessels must have <50% stenosis. Given the recent paradigm shift in our understanding of the role of plaque vulnerability in ischemic stroke risk, we evaluate the role of imaging specific high-risk extracranial plaque features in non-stenosing plaque and their potential contributions to ESUS. Further, intracranial vessel-wall MR is another potential tool to identify non-stenosing atherosclerotic plaques which may also contribute to ESUS. In this review, we discuss the role of cross-sectional imaging of the extracranial and intracranial arteries and how imaging may potentially uncover high risk plaque features which may be contributing to ischemic strokes.

Differential control of blood flow in masseter and biceps brachii muscles during stress

ObjectiveThe present study aimed to compare sympathetic hemodynamic effects in masticatory and limb muscles in response to different stressors. DesignTwelve healthy participants were subjected to a randomized series of stressors, including cold pressor test (CPT), mental arithmetic test, apnea, isometric handgrip (IHG) and post-handgrip muscle ischemia (PHGMI), while in the supine position. Spatially-resolved near-infrared spectroscopy was used to measure relative changes in blood volume and oxygenation (TOI) of the resting masseter and biceps muscles. Cardiac output, heart rate, and arterial blood pressure (ABP) were also monitored. ResultsExcept apnea, all tests increased ABP. Different response patterns were observed in the 2 muscles: TOI significantly increased during contralateral IHG (1.24 ± 1.17%) but markedly decreased during CPT (−4.84 ± 4.09%) and PHGMI (−6.65 ± 5.31%) in the biceps muscle, while exhibiting consistent increases in the masseter (1.88 ± 1.85%; 1.60 ± 1.75%; 1.06 ± 3.29%, respectively) (p < 0.05). ConclusionsThe results allow us to infer differential control of blood flow in head and limb muscles. In general, the masseter appears more prone to dilatation than the biceps, exhibiting opposite changes in response to painful stimuli (CPT and PHGMI). Several mechanisms may mediate this effect, including reduced sympathetic outflow to the extracranial vasculature of the head, generally exposed to lower hydrostatic loads than the rest of the body.

Imaging Intracranial Aneurysms in the Endovascular Era: Surveillance and Posttreatment Follow-up.

While most intracranial aneurysms (IAs) remain asymptomatic over a patient's lifetime, those that rupture can cause devastating outcomes. The increased usage and quality of neuroimaging has increased detection of unruptured IAs and driven an increase in surveillance and treatment of these lesions. Standard practice is to treat incidentally discovered unruptured IAs that confer high rupture risk as well as ruptured IAs to prevent rehemorrhage. IAs are increasingly treated with coil embolization instead of microsurgical clipping; more recently, flow diversion and intrasaccular flow disruption have further expanded the versatility and utility of endovascular IA treatment. Imaging is increasingly used for posttreatment IA follow-up in the endovascular era. While cerebral angiography remains the standard for IA characterization and treatment planning, advances in CT and CT angiography and MR angiography have improved the diagnostic accuracy of noninvasive imaging for initial diagnosis and surveillance. IA features including size, dome-to-neck ratio, location, and orientation allow rupture risk stratification and determination of optimal treatment strategy and timing. The radiologist should be familiar with the imaging appearance of common IA treatment devices and the expected imaging findings following treatment. In distinction to clipping and coil embolization, flow diversion and intrasaccular flow disruption induce progressive aneurysm obliteration over months to years. Careful assessment of the device; the treated IA; adjacent brain, bone, meninges; and involved extracranial and intracranial vasculature is crucial at posttreatment follow-up imaging to confirm aneurysm obliteration and identify short-term and long-term posttreatment complications. An invited commentary by Chatterjee is available online. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ©RSNA, 2022.

A study of clinical &amp; angiographic profile of patients with young stroke in tertiary care center of Southern Rajasthan

: Understanding the exact etiology of stroke in the young has great relevance to its prevention and management. Recent development in the surgical and interventional therapy of extra cranial and intracranial vascular diseases have made it necessary to correctly identify the causative as well as contributory factors of stroke.This cross sectional observational study was done on patients admitted in the stroke unit of Geetanjali Medical College, Udaipur of aged 15 to 50 years with stroke and who have underwent at least one standard vessel imaging procedure within 2 weeks of stroke onset. Out of 310 patients, majority of the strokes occurred in the setting of a rheumatic valvular heart disease (63.6%), with mitral valve disease being the most frequent association. Almost 80% of patients had normal ECG whereas 20% of the patients had an ECG abnormality.70% of patients had normal ECHO and the most frequent etiologic abnormality detected was valvular heart disease. Scan and MRI was done in 180 patients. The most commonly performed angiographic procedure was CT angiogram. TOF MRA was the next most commonly performed angiographic procedure. The highest yield for picking up abnormalities was noted in the CT Angiography. The yield of CT angiography was 35.4% and 37.7% for extracranial and intracranial vasculature respectively.Arterial dissections are fairly common in young population and should be considered in appropriate clinical setting and all patients should have a good and timely angiographic assessment to rule out dissections. Thus, this study highlights the importance of risk factor evaluation, and control, complete etiological evaluation including angiographic assessment in the diagnosis, management and planning of secondary prevention strategies in young patients with stroke.

Operative Anatomy of the Skull Base: 3D Exploration with a Highly Detailed Interactive Atlas.

Objective We evaluated the usefulness of a three-dimensional (3D) interactive atlas to illustrate and teach surgical skull base anatomy in a clinical setting. Study Design A highly detailed atlas of the adult human skull base was created from multiple high-resolution magnetic resonance imaging (MRI) and computed tomography (CT) scans of a healthy Caucasian male. It includes the parcellated and labeled bony skull base, intra- and extracranial vasculature, cranial nerves, cerebrum, cerebellum, and brainstem. We are reporting retrospectively on our experiences with employing the atlas for the simulation and teaching of neurosurgical approaches and concepts in a clinical setting. Setting The study was conducted at the University Hospital Mainz, Germany, and Hirslanden Hospital, Zürich, Switzerland. Participants Medical students and neurosurgical residents participated in this study. Results Handling the layered graphical user interface of the atlas requires some training; however, navigating the detailed 3D content from intraoperative perspectives led to quick comprehension of anatomical relationships that are otherwise difficult to perceive. Students and residents appreciated the collaborative learning effect when working with the atlas on large projected screens and markedly improved their anatomical knowledge after interacting with the software. Conclusion The skull base atlas provides an effective way to study essential surgical anatomy and to teach operative strategies in this complex region. Interactive 3D computer graphical environments are highly suitable for conveying complex anatomy and to train and review surgical concepts. They remain underutilized in clinical practice.

Effect of occipitoatlantal decompression on cerebral blood flow dynamics as evaluated by Doppler ultrasonography.

Osteopathic manipulative treatment reduces symptoms in patients with headache disorders, but the underlying mechanisms are unclear. To evaluate blood flow in the intracranial and extracranial vasculature before and after occipitoatlantal decompression (OAD) using Doppler ultrasonography. Healthy, first-year osteopathic medical students from A.T. Still University's Kirksville College of Osteopathic Medicine participated in a randomized, single-blinded, two-period, two-treatment crossover study. The participants were randomly assigned to 1 of 2 treatment interventions: OAD or sham touch. After one week, participants returned to have the other intervention performed. Blood flow parameters-peak systolic velocity (PSV) and end-diastolic velocity (EDV)-in the middle cerebral artery (MCA), internal carotid artery (ICA), and vertebral artery (VA) were evaluated before, immediately after, 5minutes after, and 10minutes after treatment. Differences in PSV, EDV, heart rate (HR), and blood pressure (BP) for both interventions were analyzed for the four time points using mixed-effects models. Thirty healthy medical students (11 men, 19 women; mean age, 24years) participated in this study. EDV increased after OAD in the MCA, ICA, and VA (all p<0.001); no change occurred after sham touch (all p>0.05). EDV was greater for all post-treatment timepoints after OAD in the MCA, ICA, and VA than after sham touch (all p<0.001). Although baseline PSV in the MCA measured before treatment was different between treatment interventions (p=0.01), no difference was found between interventions at any post-treatment time point (all p>0.59). Changes in PSV in the ICA and VA and for HR and BP did not depend on treatment intervention (p>0.06). Increases in EDV occurred in major cranial arteries after OAD but not after sham touch, indicating that OAD improves blood flow to the brain. The exact mechanism of this increase is unknown; however, it can be explained by either parasympathetic stimulation through the secretion of vasodilating neurotransmitters or by a decrease in external tissue pressure on ICA and VA, with the resulting flow causing further dilation in the MCA.

Ultrasound Assessment of Extracranial Carotids and Vertebral Arteries in Acute Cerebral Ischemia.

Assessing ischemic etiology and mechanism during the acute phase of an ischemic stroke is crucial in order to tailor and monitor appropriate treatment and determine prognosis. Cervical Duplex Ultrasound (CDU) has evolved since many years as an excellent screening tool for the evaluation of extracranial vasculature. CDU has the advantages of a low cost, easily applicable, bed side examination with high temporal and spatial resolution and without exposing the patients to any significant complications. It represents an easily repeatable test that can be performed in the emergency room as a first-line examination of cervical artery pathology. CDU provides well validated estimates of the type of the atherosclerotic plaque, the degree of stenosis, as well as structural and hemodynamic information directly about extracranial vessels (e.g., subclavian steal syndrome) and indirectly about intracranial circulation. CDU may also aid the diagnosis of non-atherosclerotic lesions of vessel walls including dissections, arteritis, carotid-jugular fistulas and fibromuscular dysplasias. The present narrative review outlines all potential applications of CDU in acute stroke management and also highlights its potential therapeutic implications.

Design and Physical Properties of 3-Dimensional Printed Models Used for Neurointervention: A Systematic Review of the Literature.

Three-dimensional (3D) printing has revolutionized training, education, and device testing. Understanding the design and physical properties of 3D-printed models is important. To systematically review the design, physical properties, accuracy, and experimental outcomes of 3D-printed vascular models used in neurointervention. We conducted a systematic review of the literature between January 1, 2000 and September 30, 2018. Public/Publisher MEDLINE (PubMed), Web of Science, Compendex, Cochrane, and Inspec databases were searched using Medical Subject Heading terms for design and physical attributes of 3D-printed models for neurointervention. Information on design and physical properties like compliance, lubricity, flow system, accuracy, and outcome measures were collected. A total of 23 articles were included. Nine studies described 3D-printed models for stroke intervention. Tango Plus (Stratasys) was the most common material used to develop these models. Four studies described a population-representative geometry model. All other studies reported patient-specific vascular geometry. Eight studies reported complete reconstruction of the circle of Willis, anterior, and posterior circulation. Four studies reported a model with extracranial vasculature. One prototype study reported compliance and lubricity. Reported circulation systems included manual flushing, programmable pistons, peristaltic, and pulsatile pumps. Outcomes included thrombolysis in cerebral infarction, post-thrombectomy flow restoration, surgical performance, and qualitative feedback. Variations exist in the material, design, and extent of reconstruction of vasculature of 3D-printed models. There is a need for objective characterization of 3D-printed vascular models. We propose the development of population representative 3D-printed models for skill improvement or device testing.

The Effect of Extracranial-to-Intracranial Bypass on Cerebral Vasoreactivity: A 4D Flow MRI Pilot Study.

Extracranial-to-intracranial (EC-IC) surgical bypass improves cerebral blood flow (CBF) and cerebrovascular vasoreactivity (CVR) for patients with carotid occlusion. Bypass graft patency and contribution of the graft to the postoperative increase in CVR are challenging to assess. To assess the effectiveness of 4D flow magnetic resonance imaging (MRI) to evaluate bypass graft patency and flow augmentation through the superficial temporal artery (STA) before and after EC-IC bypass. Three consecutive patients undergoing EC-IC bypass for carotid occlusion were evaluated pre- and postoperatively using CVR testing with pre- and poststimulus 4D flow-MRI for assessment of the bypass graft and intracranial vasculature. Preoperatively, 2 patients (patients 1 and 3) did not augment flow through either native STA. The third, who had evidence of extensive native EC-IC collateralization on digital subtraction angiography (DSA), did augment flow through the STA preoperatively (CVR = 1). Postoperatively, all patients demonstrated CVR > 1 on the side of bypass. The patient who had CVR > 1 preoperatively demonstrated the greatest increase in resting postoperative graft flow (from 40 to 130 mL/minute), but the smallest CVR, with a poststimulus graft flow of 160 mL/minute (CVR = 1.2). The 2 patients who did not demonstrate augmentation of graft flow preoperatively augmented postoperatively from 10 to 20 mL/minute (CVR = 2.0) and 10-80 mL/minute (CVR = 8.0), respectively. Intracranial flow was simultaneously interrogated. Two patients demonstrated mild reductions in resting flow velocities in all interrogated vessels immediately following bypass. The patient who underwent CVR testing on postoperative day 48 demonstrated a stable or increased flow rate in most intracranial vessels. Four-dimensional flow MRI allows for noninvasive, simultaneous interrogation of the intra- and extracranial arterial vasculature during CVR testing, and reveals unique paradigms in cerebrovascular physiology. Observing these flow patterns may aid in improved patient selection and more detailed postoperative evaluation for patients undergoing EC-IC bypass.

Dangerous Extracranial-Intracranial Anastomoses: What the Interventionalist Must Know.

The extracranial and intracranial circulations are richly interconnected at numerous locations, a functional connectivity which underlies their impressive capacity for adaptive plasticity in the setting of vasoocclusive disease. While evolutionarily beneficial, these connections can also result in inadvertent communication with the intracranial circulation during embolization of extracranial vessels, potentially resulting in stroke or cranial nerve palsy. While these anastomoses are always present to a certain extent, flow through them occurs under predictable circumstances, and thus embolization of the extracranial vasculature can be performed safely when knowledge of functional anatomy is combined with adherence to basic principles. Herein, we will review the anatomy of known extracranial-intracranial anastomoses and strategies for avoidance of unwanted intracranial embolization. We will also review the vascular supply to cranial nerves most at risk during common neurointerventional procedures, as well as blood supply to mucosal structures.

The prospects and pitfalls in the endovascular treatment of moyamoya disease-associated intracranial aneurysms.

Moyamoya disease (MMD) is characterized by progressive stenosis or occlusion of the distal internal carotid artery and simultaneous formation of collateral vasculature. The fragile alteration and increased hemodynamic stress in the intra- and extracranial vasculature would conjointly result in the formation of intracranial aneurysms in MMD patients. According to our classification, the MMD-associated aneurysms are divided into the major artery aneurysms (MAAs) and non-MAAs. The non-MAAs are further subdivided into the distal choroidal artery aneurysms, moyamoya vessel aneurysms, transdural collateral aneurysms, and anastomosis aneurysms. Currently, endovascular treatment (EVT) has become the main stream for the MMD-associated aneurysms. There is no difference to EVT for the MMD-associated MAAs of the non-stenosed major arteries with that in the non-MMD patients. While it is a big challenge to perform EVT for MMD-associated aneurysms in the stenosed arteries. Generally speaking, the parent arteries of the non-MAAs are slim, and super-selective catheterization is technically difficult. Most of the times, parent artery occlusion with liquid embolic agents or coils can only be performed. The vasculature in MMD patients is fragile; perioperative management and meticulous intraoperative manipulation are also very important to avoid complications during EVT. In spites of the complications, the EVT can bring good outcome in selected cases of MMD-associated aneurysms.

Notch3 family expression between human intracranial and extracranial vasculature smooth muscle cells and pericytes

Notch3 family expression between human intracranial and extracranial vasculature smooth muscle cells and pericytes

Assessment of the Most Optimal Control Tissue for Intracranial Aneurysm Gene Expression Studies

Background and Purpose- Finding adequate control tissue for intracranial aneurysm (IA) pathophysiological studies, including gene expression studies, can be challenging. We compared gene expression profiles of superficial temporal, cortical, and circle of Willis (CoW) arteries and IA in search of the most optimal control tissue for future experiments. Methods- We compared RNA-sequencing data of IA samples and of superficial temporal, cortical, and CoW artery samples using Pearson correlation, Euclidean distance, and principal component analysis. We used the Mann-Whitney U test for comparison of Pearson correlation coefficients and Euclidean distances, to assess which control tissue is most similar to IA in terms of gene expression. Other unrelated tissues were used as negative controls. Results- The cortical and the CoW arteries were more similar to IA in terms of gene expression than the superficial temporal artery. This was based on Pearson correlation (+0.023 [90% CI, 0.017/0.029; P=1.9E-09] for the cortical artery and +0.034 [90% CI, 0.028/0.040; P=6.0E-15] for the CoW artery compared with the superficial temporal artery), Euclidean distance (-25.71 [90% CI, -31.54/-20.02; P=1.9E-11] for the cortical artery and -38.09 [90% CI, -44.08/-32.19; P<2.2E-16] for the CoW artery compared with the superficial temporal artery) and principal component analysis. In all analyses, the unrelated tissues formed separate groups compared with IA and the 3 control arteries. Conclusions- The cortical arteries and the CoW arteries are better controls for gene expression studies on IA than the superficial temporal artery. This probably relates to differences in anatomy of these tissues, such as the presence of an external elastic lamina in the extracranial vasculature and absence in the intracranial vasculature, because IAs, cortical arteries, and CoW arteries are all intracranial while the superficial temporal artery is extracranial. Since CoW arteries can only be obtained postmortem, cortical arteries are preferred over CoW arteries.

Intracranial aneurysms in patients with tuberous sclerosis complex: a systematic review.

Tuberous sclerosis complex (TSC) is a rare multisystem genetic disease. Arterial wall developmental disorders, such as aneurysms, in association with TSC have been well described for extracranial vasculature. The characteristics of intracranial aneurysms (IAs) in TSC have not previously been addressed in the literature. This systematic review was performed to identify and assess the distinct characteristics of IAs in patients with TSC. The authors searched PubMed, Scopus, and Web of Science for publications describing cases of TSC and IA reported before August 7, 2018. They also report 2 cases of IAs in TSC patients treated at their own institution. Thirty-three TSC patients with a total of 42 IAs were included in this review. Three individuals presented with subarachnoid hemorrhage. The IAs were large or giant in 57.1% and fusiform in 45.2% of the cases. Most of the IAs (61.9%, 26 of 42) originated from the internal carotid artery. There was a higher prevalence of pediatric cases (66.7%) and male patients (63.6%, 21 of 32 individuals with known sex) among the collected series. TSC patients with IAs are characterized with a higher proportion of large/giant and fusiform IAs and young age, suggesting rapid aneurysmal growth. Furthermore, there is a distinct location pattern of IAs and an inverse sex ratio than in the healthy population. Large population-based patient registers are required to improve the understanding of epidemiology and pathophysiology of IA formation in TSC.

Comparative Analysis of CT and MRI in Emergency Assessment of Stroke: A Review

Objective: To compare the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI)in emergency assessment of stroke in brain imaging from the review of literature. Method: Relevant databases (PubMed, google scholar etc.) were searched and literature were reviewed from 1995 to 2019. Literature from non-Scopus and unauthorized authorizations was excluded. Result: It was observed that for MRI DWI (Diffusion-weighted imaging) is preferred and in CT, axial sections are opted. In earlier studies, it was seen that neither CT nor MRI came out to besuperior. This may be due to the previous technology used. Some studies also, suggested that Diffusion-weighted imaging is highly accurate in diagnosis of stroke and also superior to CT. Another study suggested that SWI is a new approach in visualizing the hemorrhage in acute stroke. On one hand, evidence revealed that MRI is as good as CT. While on the other hand, literature concluded that CT angiography is good for intracranial and extracranial vasculature. Some studies suggested that CT is more reliable and is readily available for stroke. Conclusion: Present study concludes that both diagnostic imaging modalities i.e., CT and MRI have their advantages in diagnosis of ischemic and hemorrhagic stroke.Also chances of stroke increases with increase in age. Other factors influencing the stroke diagnosis and treatment are type of stroke, diagnostic imaging modality available, and cost-effectiveness of diagnostic exams performed.

Venous and glymphatic drainage of the brain: Brief history of the International Society for Neurovascular Disease

The International Society of Neurovascular Diseases is an International, Interdisciplinary Scientific Organization (ISNVD: www.isnvd.org) devoted to the study of intracranial and extracranial vasculature. Different from other scientific societies, ISNVD is interested also in the investigation of the cerebral drainage, including the venous and glymphatic systems. Moreover, ISNVD promotes studies on: stroke, carotid surgery, neurovascular aspects of neurodegeneration, models of circulation, vasoactive peptides, and basic science. This review summarizes the contribution of the society to the fields above, as well as the history of the annual meetings and the major impact papers promoted by ISNVD.