Complications of cerebral angiography: a prospective analysis of 2,924 consecutive procedures

European Stroke Organisation (ESO) and European Association of Neurosurgical Societies (EANS) guideline on stroke due to spontaneous intracerebral haemorrhage

Spontaneous (non-traumatic) intracerebral haemorrhage (ICH) affects ~3.4 million people worldwide each year, causing ~2.8 million deaths. Many randomised controlled trials and high-quality observational studies have added to the evidence base for the management of people with ICH since the last European Stroke Organisation (ESO) guidelines for the management of spontaneous ICH were published in 2014, so we updated the ESO guideline. This guideline update was guided by the European Stroke Organisation (ESO) standard operating procedures for guidelines and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework, in collaboration with the European Association of Neurosurgical Societies (EANS). We identified 37 Population, Intervention, Comparator, Outcome (PICO) questions and prioritised clinical outcomes. We conducted systematic literature searches, tailored to each PICO, seeking randomised controlled trials (RCT) - or observational studies when RCTs were not appropriate, or not available - that investigated interventions to improve clinical outcomes. A group of co-authors allocated to each PICO screened titles, abstracts, and full texts and extracted data from included studies. A methodologist conducted study-level meta-analyses and created summaries of findings tables. The same group of co-authors graded the quality of evidence, and drafted recommendations that were reviewed, revised and approved by the entire group. When there was insufficient evidence to make a recommendation, each group of co-authors drafted an expert consensus statement, which was reviewed, revised and voted on by the entire group. The systematic literature search revealed 115,647 articles. We included 208 studies. We found strong evidence for treatment of people with ICH on organised stroke units, and secondary prevention of stroke with blood pressure lowering. We found weak evidence for scores for predicting macrovascular causes underlying ICH; acute blood pressure lowering; open surgery via craniotomy for supratentorial ICH; minimally invasive surgery for supratentorial ICH; decompressive surgery for deep supratentorial ICH; evacuation of cerebellar ICH > 15 mL; external ventricular drainage with intraventricular thrombolysis for intraventricular extension; minimally invasive surgical evacuation of intraventricular blood; intermittent pneumatic compression to prevent proximal deep vein thrombosis; antiplatelet therapy for a licensed indication for secondary prevention; and applying a care bundle. We found strong evidence against anti-inflammatory drug use outside of clinical trials. We found weak evidence against routine use of rFVIIa, platelet transfusions for antiplatelet-associated ICH, general policies that limit treatment within 24 h of ICH onset, temperature and glucose management as single measures (outside of care bundles), prophylactic anti-seizures medicines, and prophylactic use of temperature-lowering measures, prokinetic anti-emetics, and/or antibiotics. New evidence about the management of ICH has emerged since 2014, enabling this update of the ESO guideline to provide new recommendations and consensus statements. Although we made strong recommendations for and against a few interventions, we were only able to make weak recommendations for and against many others, or produce consensus statements where the evidence was insufficient to guide clinical decisions. Although progress has been made, many interventions still require definitive, high-quality evidence, underpinning the need for embedding clinical trials in routine clinical practice for ICH.

Is invasive fractional flow measurement accurate in intracranial stenosis? A computational simulation study

BACKGROUND

In intracranial atherosclerotic stenosis (ICAS), low fractional flow (FF) may indicate hemodynamic significance.

OBJECTIVE

To investigate, using simulation models, whether invasive measurement could accurately reflect 'true' FF, when the catheter/pressure wire might disturb focal flow during measurement.

METHODS

We recruited 5 patients with high-grade, symptomatic M1 middle cerebral artery stenosis in three-dimensional rotational angiography (3DRA). In each case, the stenotic severity was manually manipulated to 50%, 60%, 70%, and 80%. At each stenotic severity, we simulated four situations: no catheter/pressure wire insertion ('in vivo' status); only catheter inserted proximally to the ICAS; catheter inserted and pressure sensor placed at 1 cm and 2 cm distally to the ICAS lesion. The blood flow was simulated with computational fluid dynamics modeling, and FF measured as post-stenotic and pre-stenotic pressure ratio. We calculated relative differences of FFs simulated at other situations compared with in vivo status.

RESULTS

Compared with in vivo status, catheter insertion had no significant influence on simulated FFs. With pressure wire passing through the ICAS, simulated FFs slightly decreased (mostly <10%) at 50% and 60% stenoses, which significantly decreased (up to 50% and 88%) at 70% and 80% stenoses. The effects of pressure wire on FFs were similar when the pressure sensor was placed at 1 cm and 2 cm distally to the ICAS.

CONCLUSIONS

Invasive measurement of FF may overestimate the hemodynamic significance of ICAS with severe stenosis, as the pressure wire may further reduce the flow across the small residual lumen. The findings warrant verification in larger-scale studies, with information on collateral circulation and validation with other imaging modalities.

Comprehensive Analysis of Neurologic Complications following Transradial Cerebral Angiography

BACKGROUND AND PURPOSE

Transradial access (TRA) for cerebral angiography has become more popular due to fewer complications and greater patient comfort compared with transfemoral access. However, the frequency and nature of neurologic complications linked to TRA remain unclear. This study aimed to determine the incidence of symptomatic neurologic complications after transradial cerebral angiography, identify risk factors, and characterize clinical and imaging features of these complications.

MATERIALS AND METHODS

We retrospectively analyzed 1679 consecutive cases of transradial cerebral angiography from a single institution between January 2018 and December 2020. Neurologic complications were defined as any symptomatic changes confirmed by DWI revealing ischemic lesions. A case-control matching method was used to enhance the reliability of the results. Clinical, procedural, and anatomic factors were examined for predictors of neurologic complications.

RESULTS

Neurologic complications occurred in 1.0% (n = 19) of cases, with 85% occurring within 6 hours postprocedure. No significant predictors of neurologic complications could be identified among the clinical, procedural, or anatomic factors assessed. Overall, 58% of patients experienced transient or reversible complications. Patients with permanent symptoms had mild to moderate disability (mRS scores of 1 or 2), with no severe disability (mRS score ≥3). DWI commonly showed multifocal cortical or subcortical ischemic patterns, typically affecting the right middle cerebral artery territory or multiple territories, suggesting embolic mechanisms as a potential cause.

CONCLUSIONS

Neurologic complications following transradial cerebral angiography were rare but occurred early in the postprocedural period. The observed ischemic patterns, particularly the right-sided predominance, suggest embolic mechanisms as a potential cause. However, further large-scale, multicenter prospective studies are essential to identify risk factors more clearly and enhance patient safety in this increasingly utilized transradial approach.

Absence of Foramen Spinosum on Computed Tomography Scan Determines Feasibility of Middle Meningeal Artery Embolization

BACKGROUND AND OBJECTIVES

Middle meningeal artery embolization (MMAE) has emerged as a novel treatment of chronic subdural hematoma. In 0.5% of patients, however, there exists an ophthalmic origin of the middle meningeal artery (MMA) known as the recurrent meningeal artery. It is known that the recurrent MMA is associated with failure of its skeletal aperture, the foramen spinosum, to form during development. The aim of this study was to investigate MMAE feasibility as a function of the presence/absence of the foramen spinosum on preprocedure computed tomography (CT) scan.

METHODS

We performed a retrospective review of 100 consecutive patients undergoing MMAE from January 2022 to December 2023 at the Medical University of South Carolina. Preprocedure CT scan of the head was reviewed, and the presence or absence of the foramen spinosum, along with laterality, was recorded. Subsequently, angiographic studies were reviewed.

RESULTS

All patients (n = 100) had preprocedural CT scan available for review. The incidence of an absent foramen spinosum was 3% (n = 3). All absent foramen spinosum were left sided (2F, 1M). All embolization attempts in these patients were aborted due to recurrent meningeal artery. 97% of patients had patent bilateral foramen spinosum (n = 97). Two of these patients possessed partial ophthalmic contribution to the MMA (2%), and embolization was not performed. In patients with patent foramen spinosum, successful embolization was achieved in 92/97 patients (94.8%).

CONCLUSION

The review of preprocedure CT scan may serve as an opportunity to identify patients with ophthalmic arterial origin of the MMA, subverting unnecessary risks associated with catheter angiography.

Ultra-high resolution CT angiography for the assessment of intracranial stents and flow diverters using photon counting detector CT

BACKGROUND

The patency of intracranial stents may not be reliably assessed with either CT angiography or MR angiography due to imaging artifacts. We investigated the potential of ultra-high resolution CT angiography using a photon counting detector (PCD) CT to address this limitation by optimizing scanning and reconstruction parameters.

METHODS

A phantom with different flow diverters was used to optimize PCD-CT reconstruction parameters, followed by imaging of 14 patients with intracranial stents using PCD-CT. Images were reconstructed using three kernels based on the phantom results (Hv56, Hv64, and Hv72; Hv=head vascular) and one kernel to virtually match the resolution of standard CT angiography (Hv40). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements were calculated. Subjective image quality and diagnostic confidence (DC) were assessed using a five point visual grading scale (5=best, 1=worst) and a three point grading scale (1=best, 3=worst), respectively, by two independent neuroradiologists.

RESULTS

Phantom images demonstrated the highest image quality across dose levels for 0.2 mm reconstructions with Hv56 (4.5), Hv64 (5), and Hv72 (5). In patient images, SNR and CNR decreased significantly with increasing kernel sharpness compared with control parameters. All reconstructions showed significantly higher image quality and DC compared with the control reconstruction with Hv40 kernel (P<0.001), with both image quality and DC being highest with Hv64 (0.2 mm) and Hv72 (0.2 mm) reconstructions.

CONCLUSION

Ultra-high resolution PDC-CT angiography provides excellent visualization of intracranial stents, with optimal reconstructions using the Hv64 and the Hv72 kernels at 0.2 mm.

REGISTRATION

BASEC 2021-00343.

Transradial versus transfemoral access for diagnostic cerebral angiography: frequency of acute MRI findings in 500 consecutive patients at a single center

BACKGROUND

The frequency of clinically symptomatic and asymptomatic diffusion-weighted imaging (DWI) hyperintense lesions and their correlation with the transradial artery (TRA) approach is unclear.

OBJECTIVE

To assess the frequency of abnormal diffusion restriction foci on DWI following cerebral angiography (digital subtraction angiography (DSA)) with the TRA or transfemoral artery (TFA) approach and identify predictors of DWI restriction foci.

METHODS

We analysed data from consecutive diagnostic cerebral angiograms obtained between January 2021 and October 2023 at a single tertiary center. MRI DWI was performed 2 hours after DSA. Patients underwent neurological assessment periprocedurally, as well as prior to discharge.

RESULTS

500 patients were analysed; 277 (55%) procedures were performed via TRA and 223 (45%) via TFA. Overall, 74 (14.8%) patients had abnormal findings in the postprocedure MRI DWI. A higher incidence of positive DWI findings was noted in the TRA group, with 46 (16.6%) patients, compared with 28 (12.6%) in the TFA group (P=0.21). Symptomatic events occurred in seven (2.5%) of the TRA group and in two (0.9%) of the TFA cohort (P=0.31). At 60 days, the neurological deficit rate was one (0.4%) for the TRA group and one (0.4%) for the TFA group. Procedure time was the only significant predictor of DWI restriction (OR=1.04 per minute; P=0.0001).

CONCLUSION

Although there were more symptomatic or asymptomatic embolic events with TRA than with the TFA approach following elective cerebral angiography, this was not significantly different. We recommend the choice of vascular access based on patient anatomy and characteristics, aimed at improving care through enhanced safety.

Safety of Cerebral Intra-Arterial Chemotherapy for the Treatment of Malignant Brain Tumours

Background: Cerebral intra-arterial chemotherapy (CIAC) has been demonstrated to achieve tumoricidal concentrations in cerebral tumour cells that are otherwise unachievable due to the presence of the blood-brain barrier. In this study, we sought to analyze the safety of CIAC in a cohort of patients treated at the Centre intégré universitaire de santé et de services sociaux de l'Estrie-Centre hospitalier universitaire de Sherbrooke (CIUSSS-CHUS). Methods: Treatments consisted of monthly CIAC. A neurological examination and neuroimaging study (MRI) were performed before every treatment. The files of patients enrolled in our CIAC programme were reviewed. Adverse events were analyzed and categorized. Results: Overall, 2991 CIAC procedures were performed in 642 patients. Pathologies were as follows: malignant gliomas (68.7%), cerebral metastasis (17.6%), and cerebral lymphomas (13.7%). Perfusion vessels were as follows: 80% internal carotid artery and 20% vertebral artery. The chemotherapeutic agents used were carboplatin (86.4%), methotrexate (28.5%), melphalan (28.6%), and liposomal doxorubicin (2.8%). Osmotic blood-brain barrier disruption (BBBD) was induced in 30.5% of treatments. Symptomatic vascular adverse events occurred during 27 procedures (0.9%) in 26 patients (4%). Namely, 23 strokes, one carotid artery occlusion (responsible for one of the strokes), and two intratumoral and one subdural hemorrhage. The absolute risk of stroke was 1.3% and 0.5% for CIAC with or without BBBD, respectively. The use of the vertebral artery significantly increased the risk of stroke. Drug infusion-related seizures occurred in 2.5% of patients; 83.8% were associated with methotrexate and 16.2% with carboplatin. Conclusions: CIAC is a safe procedure with a 0.9% overall rate of symptomatic complications (stroke, carotid occlusion, subdural hemorrhage or intratumoral bleeding-n = 27/2991) on a treatment basis, mainly consisting of strokes (85%, n = 23), with a modified NIH Stroke Scale score of 4.1 ± 3.3.

Intracerebral haemorrhage - mechanisms, diagnosis and prospects for treatment and prevention

Intracerebral haemorrhage (ICH) is a devastating condition associated with high mortality and substantial residual disability among survivors. Effective treatments for the acute stages of ICH are limited. However, promising findings from randomized trials of therapeutic strategies, including acute care bundles that target anticoagulation therapies, blood pressure control and other physiological parameters, and trials of minimally invasive neurosurgical procedures have led to renewed optimism that patient outcomes can be improved. Currently ongoing areas of research for acute treatment include anti-inflammatory and haemostatic treatments. The implementation of effective secondary prevention strategies requires an understanding of the aetiology of ICH, which involves vascular and brain parenchymal imaging; the use of neuroimaging markers of cerebral small vessel disease improves classification with prognostic relevance. Other data underline the importance of preventing not only recurrent ICH but also ischaemic stroke and cardiovascular events in survivors of ICH. Ongoing and planned randomized controlled trials will assess the efficacy of prevention strategies, including antiplatelet agents, oral anticoagulants or left atrial appendage occlusion (in patients with concomitant atrial fibrillation), and optimal management of long-term blood pressure and statin use. Together, these advances herald a new era of improved understanding and effective interventions to reduce the burden of ICH.

MRI-Based Prediction of Macrovascular Causes of Intracerebral Hemorrhage: The MACRO Score

BACKGROUND AND OBJECTIVES

Although most spontaneous intracerebral hemorrhages (ICHs) are due to cerebral small vessel diseases (SVDs), between 1 in 7 and 1 in 10 are due to a macrovascular cause. Rapid diagnosis has important therapeutic and prognostic implications but sometimes requires digital subtraction angiography (DSA), an invasive procedure which cannot be performed in all patients. MRI provides optimal sensitivity for markers of SVD but was not included in previous risk stratification scores. We aimed to create and validate a risk stratification score for macrovascular causes of ICH including MRI findings to guide diagnosis and further investigations.

METHODS

We pooled data from 2 large observational study cohorts (London/United Kingdom and Graz/Austria) of consecutive patients with ICH who had brain MRI and at least 1 angiographic modality within 90 days of symptom onset. The primary outcome was a macrovascular cause of ICH (arteriovenous malformation/dural arteriovenous fistula, aneurysm, cavernoma, or cerebral venous thrombosis), with the diagnosis based on neurovascular multidisciplinary meetings. Using lasso logistic regression, we built the MRI Assessment of the Causes of intRacerebral haemOrrhage (MACRO) score to assess the probability of a macrovascular cause. We performed internal validation using bootstrapping and external validation in an independent cohort (Bern/Switzerland).

RESULTS

We included 1,043 patients with ICH (mean age 66 years, 42% female), 78 of whom had a macrovascular cause (7.5%). The final score includes age (0-39, 40-69, or ≥70), location of ICH (lobar, deep, or infratentorial), and SVD markers on MRI (≥1 microbleed, ≥1 lacune, presence of cortical superficial siderosis, or white matter hyperintensities using the Fazekas scale). The MACRO score showed an optimism-adjusted c-statistic of 0.90 (95% CI 0.88-0.93), superior to existing CT-based scores (p < 0.001). In external validation, the c-statistic was 0.87 (95% CI 0.80-0.94). MACRO scores ≥6 (59.5% of patients) indicated a very low risk of a macrovascular cause (0.2%), while scores ≤2 (9% of patients) indicated a high risk (48.9%).

DISCUSSION

The MRI-based MACRO score shows excellent performance in predicting the likelihood of macrovascular causes of spontaneous intracerebral hemorrhage, making it useful in guiding further investigations. Important limitations include the observational study design and the performance of DSA in a minority of patients.

Catheter-directed Cerebral and Spinal Angiography in Children

Catheter-directed angiography (CDA) is the gold standard neuroimaging study employed in the workup of most neurovascular conditions in both adults and children. When neuroangiography was first introduced in 1927 by Egas Moniz, it was performed by direct percutaneous injection of a contrast bolus into the cervical carotid arteries without catheters. This method was associated with a high risk of serious complications. Though neuroangiography was performed in the pediatric population as early as in the 1940s, it was not until the 1950s that development of Seldinger technique and angiographic catheters enabled CDA to be performed as it is today.

Magnetic Resonance Angiography Alone Is Insufficient for Diagnosis and Surgical Planning in Children With Moyamoya

BACKGROUND

The gold standard for evaluation of the severity of moyamoya vasculopathy is the Suzuki grade determined with cerebral catheter angiography (CA). With greater use of magnetic resonance angiography (MRA) it is important to understand if MRA is truly comparable to CA.

METHODS

Children with moyamoya were evaluated using the Suzuki score for CA and the modified MRA six-stage Suzuki score to describe the angiographic findings in moyamoya from initial narrowing of the distal internal carotid artery to the "puff of smoke" appearance of the lenticulostriate collaterals and finally to the disappearance of this network of collaterals. Using Cohen kappa we compared Suzuki grade based on CA with MRA in the same patients.

RESULTS

A total of 27 children with moyamoya were reviewed. We calculated a weighted Cohen kappa of 0.49 (P < 0.0001), which is a moderate correlation.

CONCLUSIONS

We suggest caution in the reliance on MRA for the diagnosis and evaluation of severity of moyamoya in children.

Correlation of Computed Tomography Angiography to Digital Subtraction Angiography in Carotid Stenosis with Real-World Assessment of Overestimation of Carotid Stenosis on Computed Tomography Angiography

OBJECTIVE

Computed tomography angiography (CTA) is a well-established diagnostic modality for carotid stenosis. However, false-positive CTA results may expose patients to unnecessary procedural complications in cases where surgical intervention is not warranted. We aim to assess the correlation of CTA to digital subtraction angiography (DSA) in carotid stenosis and characterize patients who were referred for intervention based on CTA and did not require it based on DSA.

METHODS

We retrospectively reviewed 186 patients who underwent carotid angioplasty and stenting following preprocedural CTA at our institution from April 2017 to December 2022.

RESULTS

Twenty-one of 186 patients (11.2%) were found to have <50% carotid stenosis on DSA (discordant group). Severe plaque calcification on CTA was associated with a discordant degree of stenosis on DSA (LR+=7.4). Among 186 patients, agreement between the percentage of stenosis from CTA and DSA was weak-moderate (r2=0.27, P<0.01). Among concordant pairs, we found moderate-strong agreement between CTA and DSA (adj r2=0.37) (P < 0.0001). Of 186 patients, 127 patients had CTA stenosis of ≥70%, and 59 had CTA of 50%-69%. Correlation between CTA and DSA in severe CTA stenosis was weak (r2=0.11, P<0.01).

CONCLUSIONS

In patients with stenosis found on CTA, over 88% also had stenosis on DSA, with this positive predictive value in line with previous studies. The percent-stenosis value from CTA and DSA was weakly correlated but does not affect the overall clinical judgement of stenosis. Severe calcification found on CTA may potentially indicate nonstenosis on DSA.

Efficacy and safety of a new torque-controlled angiographic catheter in cerebral angiography: A multicenter, randomized, open-label trial

Objective

We aimed to examine the effectiveness and safety of a novel torque-controlled catheter for cerebral angiography.

Methods

A total of 417 patients who underwent routine transfemoral cerebral angiography were enrolled in a randomized controlled study to compare the new torque-controlled and control group catheters. Device success was assessed on parameters such as the assessment of the common carotid artery, device rotation force, and success rate with the crossover group after the failed procedure. Four neurointerventionalists investigated the degree of satisfaction of using the new device. Superiority and non-inferiority tests of satisfaction scores were estimated for the new torque-controlled and the control group catheters.

Results

The new torque-controlled catheter showed improved performance in terms of technical device success (92.79 vs. 98.09 %, P = 0.010), crossover after technical device failure (0 vs. 86.67 %, P = 0.004), and common carotid artery access (92.79 vs. 98.56 %, P = 0.004). The flexibility and rotational force of the new torque-controlled catheter were higher than those of the control group catheters (75.48 vs. 100 %, P < 0.001). No marked adverse cerebrovascular accidents or vessel damage occurred in either group during the procedure. The differences between the two groups in terms of the device rotational force and operator satisfaction were 1.836 (1.765-1.907) and 2.092 (2.000-2.183), respectively. The new torque-controlled catheter showed superior device rotational force satisfaction, operator satisfaction, and manufacturer satisfaction, with statistical significance.

Conclusion

The new torque-controlled catheter was effective, safe, and convenient compared to the control group catheters for diagnostic cerebrovascular angiography.

Clinical and subclinical microemboli following neuroangiography in children

BACKGROUND

To assess the frequency, imaging appearances, and risk factors of brain microemboli following pediatric neuroangiography, as assessed by early diffusion-weighted MRI imaging (DWI).

METHODS

This single-center, retrospective analysis investigated early DWI post-pediatric neuroangiography. Patients aged 0-18 years who had diagnostic neuroangiography and DWI within a week postprocedure were included. Data on clinical and procedural parameters and MRI findings were recorded. Univariate and multivariate analyses were performed on the following risk factors: age, weight, vasculopathy, antiplatelet drug use, access type, intraprocedural heparin, procedure duration, neck arteries catheterized, and angiographic runs. A p-value<0.05 indicated statistical significance.

RESULTS

Eighty-two children were included (40.2% female), mean age 10.1±4.5 years (range: 7 months-17 years). There were no intraprocedural thromboembolic complications recognized. DWI positivity was seen following 3.6% (3/82) procedures: two with transient symptoms, and one instance of silent microemboli. There were no territorial infarcts or clinical stroke. Children with underlying vasculopathy had a higher risk of microemboli from angiography than children without vasculopathy (OR 31.6, p=0.02), and the OR of microemboli following transradial angiography was 79.1 (p=0.005) as compared with transfemoral angiography. Univariate and multivariate analysis showed a significant association between microemboli and number of angiographic runs (p=0.004). Follow-up MRI in all three patients showed no residual abnormal signal.

CONCLUSIONS

Cerebral microemboli are unusual following uncomplicated neuroangiography in children. However, in the presence of underlying vasculopathy and with transradial technique, the incidence approaches that reported in the adult literature. An increased association with the number of angiographic runs is an important and controllable factor.

Accuracy of duplex ultrasonography versus angiotomography for the diagnosis of extracranial internal carotid stenosis

INTRODUCTION

Internal carotid artery (ICA) stenosis causes about 15% of ischemic strokes. Duplex ultrasonography (DUS) is the first line of investigation of ICA stenosis, but its accuracy varies in the literature and it is usual to complement the study with another more accurate exam when faced with significant stenosis. There is a lack of studies that compare DUS with angiotomography (CTA) in the present literature.

METHODS

we performed an accuracy study, which compared DUS to CTA of patients in a tertiary hospital with a maximum interval of three months between tests. Patients were selected retrospectively, and two independent and certified vascular surgeons evaluated each image in a masked manner. When there was discordance, a third evaluator was summoned. We evaluated the diagnostic accuracy of ICA stenosis of 50-94% and 70-94%.

RESULTS

we included 45 patients and 84 arteries after inclusion and exclusion criteria applied. For the 50-94% stenosis range, DUS accuracy was 69%, sensitivity 89%, and specificity 63%. For the 70-94% stenosis range, DUS accuracy was 84%, sensitivity 61%, and specificity 93%. There was discordance between CTA evaluators with a change from clinical to surgical management in at least 37.5% of the conflicting reports.

CONCLUSION

DUS had an accuracy of 69% for stenoses of 50-94% and 84% for stenoses of 70-94% of the ICA. The CTA analysis depended directly on the evaluator with a change in clinical conduct in more than 37% of cases.

Cerebral thromboembolic complications during cerebral angiography and their risk factors in different subgroups: Analysis of 2,457 procedures

PURPOSE

Diagnostic cerebral digital subtraction angiography (DSA) is an invasive examination that involves catheterization of the major supra-aortic arterial trunks and evaluation of intracranial vessels for diagnostic purposes. Although considered the gold standard method for investigating cerebrovascular diseases, DSA carries measurable and potentially serious complication rates. This report describes the frequency of neurological and non-neurological complications of DSA performed in five hospitals in the state of São Paulo, Brazil, and analyzes them in different disease subgroups. It has a special focus on thromboembolic cerebral complications.

METHODS

We retrospectively reviewed clinical records of all adult patients who underwent DSAs between January 2019 and December 2022. Demographic variables, DSA reports, CT/MRI reports, and clinical follow-up notes were reviewed.

RESULTS

Twenty-four patients experienced some type of complication among 2,457 diagnostic DSAs (0.97%). Thromboembolic complications were recorded in 9 patients (0.36%), and access site hematomas larger than 5 cm were registered in six patients (0.24%). There was a statistical trend for thromboembolic complications in patients with cervical and/or intracranial atherosclerosis (p = 0.07), but age was not associated with them (p = 0.93). Patients who received heparin had lower rates of embolic complications than those who did not receive it, but there was no statistically significant difference (p = 0.17). Intravenous administration of heparin showed a trend toward significance with groin hematoma (p = 0.10).

CONCLUSION

Diagnostic catheter DSAs have low complication rates.

Imaging follow-up strategy after endovascular treatment of Intracranial aneurysms: A literature review and guideline recommendations

OBJECTIVE

Endovascular coil embolization is the primary treatment modality for intracranial aneurysms. However, its long-term durability remains of concern, with a considerable proportion of cases requiring aneurysm reopening and retreatment. Therefore, establishing optimal follow-up imaging protocols is necessary to ensure a durable occlusion. This study aimed to develop guidelines for follow-up imaging strategies after endovascular treatment of intracranial aneurysms.

METHODS

A committee comprising members of the Korean Neuroendovascular Society and other relevant societies was formed. A literature review and analyses of the major published guidelines were conducted to gather evidence. A panel of 40 experts convened to achieve a consensus on the recommendations using the modified Delphi method.

RESULTS

The panel members reached the following consensus: 1. Schedule the initial follow-up imaging within 3-6 months of treatment. 2. Noninvasive imaging modalities, such as three-dimensional time-of-flight magnetic resonance angiography (MRA) or contrast-enhanced MRA, are alternatives to digital subtraction angiography (DSA) during the first follow-up. 3. Schedule mid-term follow-up imaging at 1, 2, 4, and 6 years after the initial treatment. 4. If noninvasive imaging reveals unstable changes in the treated aneurysms, DSA should be considered. 5. Consider late-term follow-up imaging every 3-5 years for lifelong monitoring of patients with unstable changes or at high risk of recurrence.

CONCLUSIONS

The guidelines aim to provide physicians with the information to make informed decisions and provide patients with high-quality care. However, owing to a lack of specific recommendations and scientific data, these guidelines are based on expert consensus and should be considered in conjunction with individual patient characteristics and circumstances.

Diagnosis and management of subarachnoid haemorrhage

Aneurysmal subarachnoid haemorrhage (aSAH) presents a challenge to clinicians because of its multisystem effects. Advancements in computed tomography (CT), endovascular treatments, and neurocritical care have contributed to declining mortality rates. The critical care of aSAH prioritises cerebral perfusion, early aneurysm securement, and the prevention of secondary brain injury and systemic complications. Early interventions to mitigate cardiopulmonary complications, dyselectrolytemia and treatment of culprit aneurysm require a multidisciplinary approach. Standardised neurological assessments, transcranial doppler (TCD), and advanced imaging, along with hypertensive and invasive therapies, are vital in reducing delayed cerebral ischemia and poor outcomes. Health care disparities, particularly in the resource allocation for SAH treatment, affect outcomes significantly, with telemedicine and novel technologies proposed to address this health inequalities. This article underscores the necessity for comprehensive multidisciplinary care and the urgent need for large-scale studies to validate standardised treatment protocols for improved SAH outcomes.

Surgical Management of Intraosseous Neurofibroma in Cervical Spine: A Case Report

CASE

A 30-year-old man had cervical radiculomyelopathy and neck pain caused by a massive intraosseous neurofibroma (IONF) originating from the C6 vertebrae. We performed posterior tumor resection with spinal instrumentation and fusion from C3 to T2 and a follow-up resection procedure of the remaining C6 anterior tumor, sacrificing the affected vertebral artery (VA), which accordingly required bypass surgery at 2 months recovery. Reconstruction using a titanium mesh cage was successfully performed. There were no local recurrences at 2 years postoperatively.

CONCLUSIONS

Total tumor resection split into 2 stages with sacrifice of the affected VA is a feasible option for treatment of IONF.

Which Patients Receive Diagnostic Angiography? An EAST Multicenter Study Analysis of Internal Carotid Artery Blunt Cerebrovascular Injury

BACKGROUND

Digital subtraction angiography (DSA) is the gold standard radiologic modality in blunt cerebrovascular injury (BCVI). However, computerized tomography angiography (CTA) is primarily used in modern practice with CTA's widespread availability and the decreased stroke rate with CTA use. The frequency and indications for DSA in BCVI is undefined. We hypothesized that DSA use in internal carotid artery (ICA) BCVI would be infrequent and dependent on radiologic features.

METHODS

This was a post hoc analysis of an EAST multicenter, prospective, observational trial of 16 trauma centers for stroke factors in BCVI. ICA BCVI was divided into those undergoing DSA and not undergoing DSA (no-DSA). Only ICA BCVI was included.

RESULTS

332 ICA BCVI were included, 221 (66.6%) no-DSA and 111 (33.4%) DSA. Lower hospital trauma volume, non-urban environment, and non-academic status were associated with DSA use (all P ≤ .001). BCVI grade (P = .02) and presence of luminal stenosis (P = .005) were associated with DSA use while pseudoaneurysm presence was not. Median time to DSA was 1 hour. The most common indication for angiography was to determine the presence of injury in 71 (64%) ICA BCVI, followed by determining grade of injury in 16 (14.4%) and concerning imaging characteristics in 12 (10.8%). BCVI grade on initial imaging and on DSA were equivalent in 94 (84.7%) ICA BCVI.

DISCUSSION

DSA is frequently used in ICA BCVI, primarily early in the hospital course for injury diagnosis and grade determination. DSA appears primarily driven by hospital type, BCVI grade, and luminal stenosis.

Predictors of Transfemoral Access Site Complications in Neuroendovascular Procedures: A large Single-Center Cohort Study

OBJECTIVE

The transfemoral (TF) route has historically been the preferred access site for endovascular procedures. However, despite its widespread use, TF procedures may confer morbidity as a result of access site complications. The aim of this study is to provide the rate and predictors of TF access site complications for neuroendovascular procedures.

METHODS

This is a single center retrospective study of TF neuroendovascular procedures performed between 2017 and 2022. The incidence of complications and associated risk factors were analyzed across a large cohort of patients.

RESULTS

The study comprised of 2043 patients undergoing transfemoral neuroendovascular procedures. The composite rate of access site complications was 8.6 % (n = 176). These complications were divided into groin hematoma formation (n = 118, 5.78 %), retroperitoneal hematoma (n = 14, 0.69 %), pseudoaneurysm formation (n = 40, 1.96 %), and femoral artery occlusion (n = 4, 0.19 %). The cross-over to trans radial access rate was 1.1 % (n = 22). On univariate analysis, increasing age (OR=1.0, p = 0.06) coronary artery disease (OR=1.7, p = 0.05) peripheral vascular disease (OR=1.9, p = 0.07), emergent mechanical thrombectomy procedures (OR=2.1, p < 0.001) and increasing sheath size (OR=1.3, p < 0.001) were associated with higher TF access site complications. On multivariate analysis, larger sheath size was an independent risk factor for TF access site complications (OR=1.8, p = 0.02).

CONCLUSION

Several pertinent factors contribute towards the incidence of TF access site complications. Factors associated with TF access site complications include patient demographics (older age) and clinical risk factors (vascular disease), as well as periprocedural factors (sheath size).

Spectrum of Complications and Complication Rates After Diagnostic Catheter Angiography in Neuroradiology

PURPOSE

To retrospectively evaluate the total complication rates and type of complications after diagnostic cerebral and spinal catheter angiography.

METHODS

Data from 2340 patients undergoing diagnostic angiography over a period of 10 years in a neuroradiologic center were retrospectively evaluated. Local, systemic, neurological, and technical complications were analyzed.

RESULTS

A total of 75 clinically noted complications occurred. The risk for clinical complications was increased when the angiography was performed under emergency conditions (p = 0.009). The most common complication was groin hematoma (1.32%). Neurological complications occurred in 0.68% of patients, of which 0.13% were stroke with permanent disability. Technical complications without noticeable clinical symptoms of the patients occurred in 2.35% of the angiographic procedures. Deaths caused by angiography did not occur.

CONCLUSION

There is a definite risk for complications after diagnostic angiography. Although a very broad spectrum of complications was considered, complications in the individual subgroups showed a low incidence.

Comparison of bone subtraction CT angiography with standard CT angiography for evaluating circle of Willis in normal dogs

BACKGROUND

Bone subtraction computed tomography angiography (BSCTA) is a useful alternative technique for improving visualization of vessels surrounded by skull bone. However, no studies have compared computed tomography angiography (CTA) and BSCTA for improving the visibility of canine cerebral blood vessels.

OBJECTIVES

To evaluate the potential benefit of BSCTA for better delineation of brain arteries of the circle of Willis (CoW) in dogs by comparing BSCTA with non-subtraction computed tomography angiography (NSCTA).

METHODS

Brain CTA was performed for nine healthy beagle dogs using a bolus tracking method with saline flushing. A total dose of 600 mgI/kg of contrast agent with an iodine content of 370 mgI/mL was injected at a rate of 4 ml/s. Bone removal was achieved automatically by subtracting non-enhanced computed tomography (CT) data from contrast CT data. Five main intracranial arteries of the CoW were analyzed and graded on a scale of five for qualitative evaluation.

RESULTS

Scores of basilar artery, middle cerebral artery, and rostral cerebral artery in the BSCTA group were significantly higher than those in the NSCTA group (p = 0.001, p = 0.020, and p < 0.0001, respectively). Scores of rostral cerebellar artery (RcA) and caudal cerebral artery (CCA) did not differ significantly between the two groups. However, scores of RcA and CCA in the BSCTA group were higher than those in the NSCTA group.

CONCLUSIONS

BSCTA improved visualization of intracranial arteries of the CoW with close contact to bone. Thus, it should be recommended as a routine scan method in dogs suspected of having brain vessel disease.

Changes in blood and renal function in patients after cerebral digital subtraction angiography

Objective

Describe the incidence of contrast-induced acute renal injury (CI-AKI) and the changes in hematocrit in a cohort of patients undergoing elective cerebral digital subtraction angiography (DSA).

Methods

In this prospective study, patients undergoing cerebral DSA were assessed for hematocrit level and CI-AKI risk factors before the procedure and for developing CI-AKI 72 h after exposure to the contrast media.

Results

Among 215 patients (109 men, mean age 36.6 years). The most frequently found CI-AKI risk factor was hypertension. There were no cases of permanent renal impairment after 14 days. Significant changes were observed in hematocrit (45.7 ± 4.9, vs. 44.5 ± 4.6, p = 0.001), estimated creatinine clearance (129.7 ± 48.3, vs. 123.1 ± 40.5, p = 0.002), and serum creatinine (0.72 ± 0.19, vs 0.74 ± 0.18, p = 0.031). The mean change in serum creatinine 72 h after contrast administration was +0.27 ± 0.10 mg/dL (p < 0.05).

Conclusions

The incidence of CI-AKI after elective cerebral DSA was 1.4%. A significant decrease in hematocrit was observed up to 72 h after the procedure.

The accuracy of non-contrast brain CT scan in predicting the presence of a vascular etiology in patients with primary intracranial hemorrhage

Spontaneous intraparenchymal cerebral hemorrhages (SIPH) account for 10-15% of acute strokes. Sorting these patients according to the risk of harboring an underlying vascular etiology may help selecting the patients who would mostly benefit from Multidetector CT Angiography (MDCTA). The aim of this study was to evaluate the accuracy of Non-Contrast brain CT (NCCT) in predicting possible vascular etiologies in patients with SIPH. In this retrospective study, we evaluated the NCCT of 334 patients who presented with SIPH from March 2017 to March 2021 and we looked for vascular etiologies in the CTA which was performed for these patients. We used NCCT criteria to predict the presence of any vascular etiologies in SIPH patients and proposed a scoring system based on these criteria which might predict the risk of vascular ICH (VICH score). Out of 334 evaluated patients, 9.3% had an underlying vascular etiology. Independent predictors of the vascular etiology included: age < 46 years, no history of hypertension and coagulation disorders, lobar hemorrhages, and presence of significant perilesional edema. We used these criteria and NCCT classification to create a practical scoring system to predict the risk of vascular ICH (VICH). In our study, VICH score ≥ 4 had 51.6% sensitivity and 96.4% specificity for predicting a positive MDCTA as the maximum optimal cut-off point. The VICH score seemed to be successful in predicting vascular etiologies in this retrospective cohort of 334 patients. This scoring system can be used to select patients if there are limited resources to perform CT angiography.

'Diagnostic anchoring' and a delayed diagnosis of reversible cerebral vasoconstriction syndrome

We present a case of a woman in her 60s with acute left hemispheric ischaemic stroke syndrome due to tandem occlusions of the proximal left internal carotid artery and left middle cerebral artery. This was treated with emergent carotid artery stenting and endovascular clot retrieval. The patient made a complete recovery and was discharged home only to represent a few days later with focal neurological symptoms, profound headache and labile blood pressure. The diagnostic and management challenges of reversible cerebral vasoconstriction syndrome, including imaging assessment and the importance of avoiding 'diagnostic anchoring' are discussed.

Frequency and Pattern of MRI Diffusion Restrictions after Diagnostic Catheter Neuroangiography

(1) Background: We investigated the frequency, location, and lesion size of diffusion restrictions (DR) in magnetic resonance imaging (MRI) of asymptomatic patients after diagnostic angiography and assessed risk factors for their occurrence. (2) Methods: We analyzed diffusion-weighted images (DWI) of 344 patients undergoing diagnostic angiographies in a neuroradiologic center. Only asymptomatic patients who received a magnetic resonance imaging (MRI) examination within seven days after the angiography were included. (3) Results: Asymptomatic infarcts on DWI were identified in 17% of the cases after diagnostic angiography. In these 59 patients, a total of 167 lesions were noted. The diameter of the lesions was 1-5 mm in 128 lesions, and 5-10 mm in 39 cases. Dot-shaped diffusion restrictions were found most frequently (n = 163, 97.6%). None of the patients had neurological deficits during or after angiography. Significant correlations were found between the occurrence of lesions and patient age (p < 0.001), history of atherosclerosis (p = 0.014), cerebral infarction (p = 0.026), or coronary heart disease/heart attack (p = 0.027); and the amount of contrast medium used (p = 0.047) and fluoroscopy time (p = 0.033). (4) Conclusions: With an incidence of 17%, we observed a comparatively high risk for asymptomatic cerebral ischemia after diagnostic neuroangiography. Further measures to reduce the risk of silent embolic infarcts and improve the safety of neuroangiography are warranted.

Incidence, Clinical Significance, and Longitudinal Signal Characteristics of Ischemic Lesions Related to Diagnostic Cerebral Catheter Angiography

PURPOSE

Cerebral DSA is a routine procedure with few complications. However, it is associated with presumably clinically inapparent lesions detectable on diffusion-weighted MRI imaging (DWI lesions). However, there are insufficient data regarding incidence, etiology, clinical relevance, and longitudinal development of these lesions. This study prospectively evaluated subjects undergoing elective diagnostic cerebral DSA for the occurrence of DWI lesions, potentially associated clinical symptoms and risk factors, and longitudinally monitored the lesions using state-of-the-art MRI.

MATERIALS AND METHODS

Eighty-two subjects were examined by high-resolution MRI within 24 h after elective diagnostic DSA and lesion occurrence was qualitatively and quantitatively evaluated. Subjects' neurological status was assessed before and after DSA by clinical neurological examination and a perceived deficit questionnaire. Patient-related risk factors and procedural DSA data were documented. Subjects with lesions received a follow-up MRI and were questioned for neurological deficits after a median of 5.1 months.

RESULTS

After DSA, 23(28%) subjects had a total of 54 DWI lesions. Significantly associated risk factors were number of vessels probed, intervention time, age, arterial hypertension, visible calcified plaques, and less examiner experience. Twenty percent of baseline lesions converted to persistent FLAIR lesions at follow-up. After DSA, none of the subjects had a clinically apparent neurological deficit. Self-perceived deficits were nonsignificantly higher at follow-up.

CONCLUSION

Cerebral DSA is associated with a considerable number of postinterventional lesions, some persisting as scars in brain tissue. Presumably because of the small lesion size and inconsistent location, no clinically apparent neurological deficits have been observed. However, subtle self-perceived changes may occur. Therefore, special attention is needed to minimize avoidable risk factors.

Subarachnoid Hemorrhage with Negative Initial Digital Subtraction Angiography: Subsequent Detection of Aneurysms and Complication Rates of Repeated Angiography

BACKGROUND

 The data on handling of spontaneous, nontraumatic subarachnoid hemorrhage (SAH) with negative initial digital subtraction angiography (DSA) are still inconclusive. The intention of this study was to evaluate the requirement of repeat DSA in patients with negative initial DSA and to compare the clinical outcomes of these cases.

METHODS

 In a retrospective study, we reviewed patients with SAH and negative initial DSA treated in our department from January 2006 until December 2017. The patients were divided according to an established radiographic classification into perimesencephalic (pm) and nonperimesencephalic (npm) SAH. An interventional neuroradiologist and a neurosurgeon reviewed all DSA scans.

RESULTS

 In all, 52 patients with negative initial DSA, comprising 36 (69.2%) patients with pm and 16 (30.8%) patients with npm bleeding pattern, were included. All patients underwent a second and 23 of these patients underwent a third DSA. In these 23 patients, subarachnoid blood distribution in the initial computed tomography (CT) scan was suspicious for the presence of aneurysm. In total, two aneurysms were detected during the second DSA (diagnostic yield: 3.85%). Both were in the pm group (diagnostic yield: 5.6%). The second repeat DSA did not show any causative vascular lesion. Complications after the DSA occurred in only 2 of 127 patients (1.6%). The rate of complications concerning vasospasm (pm 52.8%, npm 56.3%), hydrocephalus (pm 47.2%, npm 50%), and the need for temporary or permanent shunt (pm 44.4%, npm 50%) was similar in both groups and there was no statistically significant difference.

CONCLUSION

 Repeat DSA after negative initial DSA in pm SAH had a diagnostic yield of 5.6%. However, a second repeat DSA cannot be recommended in case of SAH with initial negative DSA. The pm SAH should not be underrated concerning the occurrence of complications and cared with a high level of surveillance.

Atypical Presentation of Traumatic Pediatric Carotid Artery Dissection: A Case Report

Introduction: Carotid artery dissection is a rare but serious condition manifesting with signs and symptoms that closely overlap with other more benign medical diagnoses. This vascular injury, however, can result in debilitating sequelae, including thromboembolic cerebrovascular accidents. Case Report: We describe the atypical presentation of a healthy eight-year-old male who presented to the emergency department (ED) with generalized abdominal pain and non-bloody, non-bilious emesis. These symptoms occurred nine days after he sustained blunt head trauma after a non-syncopal fall from standing while playing hockey. He was initially diagnosed with gastroesophageal reflux disease and constipation and was discharged home. The following day he developed an acute headache followed shortly by gait ataxia, prompting a return visit to the ED. Imaging of the head and neck revealed a left internal carotid artery dissection. The patient was started on intravenous unfractionated heparin and admitted to the hospital. He was later discharged symptom-free on therapeutic enoxaparin for eight weeks, followed by daily aspirin therapy. Conclusion: Pediatric trauma patients, especially those sustaining insult to the head and cervical spine, are at risk for craniocervical arterial injuries. This rare but dangerous pathology often manifests in a non-specific, delayed fashion making it a challenging diagnosis for physicians to make on the initial medical encounter.1,2 Maintaining a high clinical suspicion for carotid artery dissection is required to make this diagnosis and should guide a thorough history, physical examination, and appropriate imaging in order to improve patient morbidity and mortality. This case emphasizes key clinical features and risk factors of this disease that may help emergency clinicians promptly recognize and treat this entity.

Computed Tomography Perfusion Imaging Study of Intracranial Complex Aneurysms Treated by Internal Maxillary Artery Bypass Grafting

BACKGROUND

Cerebral revascularization strategies through extracranial to intracranial bypass have been adopted in the management of complex intracranial aneurysms. The internal maxillary artery used as a donor in a bypass is an effective method. At present, there are few quantitative analyses of cerebral blood flow perfusion. The main focus of this study was to evaluate the effectiveness of blood perfusion after bypass grafting.

METHODS

From April 2015 to December 2017, 19 patients who underwent internal maxillary artery radial artery middle cerebral artery bypass surgery with unobstructed bypass vessels were selected. Cerebral blood flow perfusion before and after bypass surgery was quantitatively evaluated by computed tomography perfusion imaging. The cerebral blood perfusion in the region of interest was measured by computed tomography perfusion.

RESULTS

The aneurysms were excised after trapping in 2 cases with mass effects and neural compression. Proximal occlusion of the parent artery was performed in 9 cases of fusiform or giant dissecting aneurysms. Trapping was performed after bypass surgery in 8 cases. Within 3 months after surgery, 17 patients had good outcomes. After the hypothesis test, there was a significant difference between the preoperative △cerebral blood volume and postoperative △cerebral blood volume in the anterior area of the semioval center cross section (P = 0.001 < 0.05).

CONCLUSIONS

The internal maxillary artery as a bypass donor is an effective method that can provide sufficient intracranial blood perfusion, and there is usually no cerebral ischemia in the surrounding area.

Transradial versus Transfemoral Approaches in Diagnostic and Therapeutic Neuroendovascular Interventions: A Meta-Analysis of Current Literature

BACKGROUND

The adoption of the transradial approach (TRA) has been increasing in popularity as a primary method to conduct both diagnostic and therapeutic interventions. As this technique gains broader acceptance and use within the neuroendovascular community, comparing its complication profile with a better-established alternative technique, the transfemoral approach (TFA), becomes more important. This study aimed to evaluate the safety of TRA compared with TFA in patients undergoing diagnostic, therapeutic, and combined neuroendovascular procedures.

METHODS

A systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search of PubMed and other databases was conducted for studies from all available dates. To compare TRA and TFA, we performed an indirect meta-analysis between studies that mentioned the complications of the procedures.

RESULTS

Our search yielded 532 studies, of which 108 met full inclusion criteria. A total of 54,083 patients (9137 undergoing TRA and 44,946 undergoing TFA) were included. Access site complication rate was lower in TRA (1.62%) compared with TFA (3.31%) (P < 0.01). Neurological complication rate was lower in TRA (1.64%) compared with TFA (3.82%) (P = 0.02 and P < 0.01, respectively). Vascular spasm rate was higher in TRA (3.65%) compared with TFA (0.88%) (P < 0.01). Wound infection complication rate was higher in TRA (0.32%) compared with TFA (0.2%) (P < 0.01).

CONCLUSIONS

Patients undergoing TFA are significantly more likely to experience access site complications and neurological complications compared with patients undergoing TRA. Patients undergoing TRA are more likely to experience complications such as wound infections and vascular spasm.

Angiographic Pulse Wave Coherence in the Human Brain

A stroke volume of arterial blood that arrives to the brain housed in the rigid cranium must be matched over the cardiac cycle by an equivalent volume of ejected venous blood. We hypothesize that the brain maintains this equilibrium by organizing coherent arterial and venous pulse waves. To test this hypothesis, we applied wavelet computational methods to diagnostic cerebral angiograms in four human patients, permitting the capture and analysis of cardiac frequency phenomena from fluoroscopic images acquired at faster than cardiac rate. We found that the cardiac frequency reciprocal phase of a small region of interest (ROI) in a named artery predicts venous anatomy pixel-wise and that the predicted pixels reconstitute venous bolus passage timing. Likewise, a small ROI in a named vein predicts arterial anatomy and arterial bolus passage timing. The predicted arterial and venous pixel groups maintain phase complementarity across the bolus travel. We thus establish a novel computational method to analyze vascular pulse waves from minimally invasive cerebral angiograms and provide the first direct evidence of arteriovenous coupling in the intact human brain. This phenomenon of arteriovenous coupling may be a physiologic mechanism for how the brain precisely maintains mechanical equilibrium against volume displacement and kinetic energy transfer resulting from cyclical deformations with each heartbeat. The study also paves the way to study deranged arteriovenous coupling as an underappreciated pathophysiologic disturbance in a myriad of neurological pathologies linked by mechanical disequilibrium.

Endoluminal Biopsy for Molecular Profiling of Human Brain Vascular Malformations

BACKGROUND AND OBJECTIVES

Ras-mitogen-activated protein kinase (MAPK) signaling abnormalities occur in most brain arteriovenous malformations (bAVMs). No means exist to molecularly profile bAVMs without open surgery, limiting precision medicine approaches to treatment. Here, we report use of endoluminal biopsy of the vessel lumen of bAVMs to characterize gene expression and blood flow-mediated transcriptional changes in living patients.

METHODS

Endoluminal biopsy and computational fluid dynamic modeling (CFD) were performed in adults with unruptured AVMs with cerebral angiography. Each patient underwent surgical resection and cell sampling from a contiguous arterial segment. Fluorescence-assisted cell sorting enriched endothelial cells, which were sequenced on an Illumina HiSeq 4000 sequencer. Gene expression was quantified with RNA sequencing (RNAseq). Differential gene expression, ontology, and correlative analyses were performed. Results were validated with quantitative reverse transcription PCR (RT-qPCR).

RESULTS

Endoluminal biopsy was successful in 4 patients without complication. Endoluminal biopsy yielded 269.0 ± 79.9 cells per biopsy (control 309.2 ± 86.6 cells, bAVM 228.8 ± 133.4 cells). RNAseq identified 106 differentially expressed genes (DEGs) in bAVMs (false discovery rate ≤0.05). DEGs were enriched for bAVM pathogenic cascades, including Ras-MAPK signaling (p < 0.05), and confirmed with RT-qPCR and a panel predictive of MAPK/extracellular signal-regulated kinase inhibitor response. Compared to patient-matched surgically excised tissues, endoluminal biopsy detected 83.3% of genes, and genome-wide expression strongly correlated (Pearson r = 0.77). Wall shear stress measured by CFD correlated with inflammatory pathway upregulation. Comparison of pre-embolization and postembolization samples confirmed flow-mediated gene expression changes.

DISCUSSION

Endoluminal biopsy allows molecular profiling of bAVMs in living patients. Gene expression profiles are similar to those of tissues acquired with open surgery and identify potentially targetable Ras-MAPK signaling abnormalities in bAVMs. Integration with CFD allows determination of flow-mediated transcriptomic alterations. Endoluminal biopsy may help facilitate trials of precision medicine approaches to bAVMs in humans.

Planning of gamma knife radiosurgery (GKR) for brain arteriovenous malformations using triple magnetic resonance angiography (triple-MRA)

PURPOSE

Intra-arterial Digital Subtraction Angiography (DSA) is the gold standard technique for radiosurgery target delineation in brain Arterio-Venous Malformations (AVMs). This study aims to evaluate whether a combination of three Magnetic Resonance Angiography sequences (triple-MRA) could be used for delineation of brain AVMs for Gamma Knife Radiosurgery (GKR).

METHODS

Fifteen patients undergoing DSA for GKR targeting of brain AVMs also underwent triple-MRA: 4D Arterial Spin Labelling based angiography (ASL-MRA), Contrast-Enhanced Time-Resolved MRA (CE-MRA) and High Definition post-contrast Time-Of-Flight angiography (HD-TOF). The arterial phase of the AVM nidus was delineated on triple-MRA by an interventional neuroradiologist and a consultant neurosurgeon (triple-MRA volume). Triple-MRA volumes were compared to AVM targets delineated by the clinical team for delivery of GKR using the current planning paradigm, i.e., stereotactic DSA and volumetric MRI (DSA volume). Difference in size, degree of inclusion (DI) and concordance index (CcI) between DSA and triple-MRA volumes are reported.

RESULTS

AVM target volumes delineated on triple-MRA were on average 9.8% smaller than DSA volumes (95%CI:5.6-13.9%; SD:7.14%; p = .003). DI of DSA volume in triple-MRA volume was on average 73.5% (95%CI:71.2-76; range: 65-80%). The mean percentage of triple-MRA volume not included on DSA volume was 18% (95%CI:14.7-21.3; range: 7-30%).

CONCLUSION

The technical feasibility of using triple-MRA for visualisation and delineation of brain AVMs for GKR planning has been demonstrated. Tighter and more precise delineation of AVM target volumes could be achieved by using triple-MRA for radiosurgery targeting. However, further research is required to ascertain the impact this may have in obliteration rates and side effects.

Contrast-induced encephalopathy and nonconvulsive status epilepticus after diagnostic cerebral angiography in an end-stage renal disease patient

A 70-year-old man with a history of recurrent ischemic stroke and end-stage renal disease was admitted to the neurology department for a transient ischemic attack. The patient underwent transfemoral cerebral angiography with iopamidol to evaluate the status of carotid stenosis. On the same day, the patient developed drowsy mentality, global aphasia, and fever. Electroencephalography showed continuous regional rhythmic delta activities (0.5 to 1.0 Hz) without definite spatiotemporal evolution, suggestive of focal seizure disorder arising from the left temporal area and ictal-interictal continuum. Computed tomography perfusion images showed hyperperfusion in the left hemisphere. The patient was diagnosed with contrast-induced encephalopathy and associated nonconvulsive status epilepticus. The patient was treated with oral lacosamide, levetiracetam, and daily hemodialysis. The patient’s mental status recovered after 8 days of intensive care unit care.

Intracranial varix of the transverse-sigmoid dural arteriovenous fistula mimicking a ruptured middle cerebral artery aneurysm: A case report

Background:

Hemorrhagic stroke is caused by various vascular abnormalities, such as aneurysms, arteriovenous malformations, and dural arteriovenous fistulas (DAVF). Magnetic resonance angiography (MRA) and three-dimensional computed tomography angiography (3DCTA) are used as efficient initial diagnostic modalities in assessing the etiology of hemorrhagic stroke. We describe the unusual case of a false-positive aneurysm on MRA and 3DCTA.

Case Description:

A 65-year-old nonhypertensive woman was brought to our hospital with a sudden onset of headache and left hemiparesis. She also had chemosis in the right eye. CT and magnetic resonance imaging showed an intracerebral hemorrhage in the right temporal lobe. MRA and 3DCTA showed a rounded mass suggestive of an aneurysm arising from the bifurcation of the middle cerebral artery (MCA) and also demonstrated an abnormal tortuous vessel contacting with a rounded mass. Digital subtraction angiography showed a transversesigmoid sinus DAVF with a varix in contact with the MCA bifurcation. Hematoma evacuation and venous drainage disconnection through the right frontotemporal craniotomy were performed.

Conclusion:

This case is very instructive and clinicians should keep in mind that detailed neurological and radiological examinations are essential in obtaining an accurate diagnosis, especially if the bleeding source is similar in shape and location to common lesions (such as a cerebral aneurysm).

Magnetic Resonance Angiography after Flow Diversion: The use of complementary MRA techniques to monitor aneurysm occlusion as well as device and arterial branch patency after flow diverter placement

BACKGROUND

Few studies have been performed to evaluate flow diversion with MRA. They have shown better success for MRA to assess the aneurysm response but limited success for the stent patency. Further, the patency of arterial branches on MRA remains to be explored.

METHODS

31 consecutive cases of carotid aneurysms treated with flow diversion were retrospectively evaluated with noncontrast time of flight (TOF), contrast enhanced TOF (CTOF) and cine MRA (TWIST) independently by two investigators for aneurysm occlusion, stent patency and arterial branch patency. DSA served as the gold standard technique.

RESULTS

There were 6 males and 25 females in the age range of years (mean ±SD). Stent patency, aneurysm occlusion and branch patency, mostly revealed substantial to perfect interobserver agreement (k >0.60). The sensitivity, specificity, positive and negative predictive values for the stent patency on source images of TOF were 0.99,0.84, 0.42 and 0.99 and on CTOF were 0.99, 0.89, 0.50 and 0.99 respectively.Sensitivity for the aneurysm response on the three MRAs ranged from 0.88 to 0.93,specificity from 0.64 to 0.75, positive predictive value from 0.69 to 0.79 and negative predictive value from 0.86 to 0.90. Sensitivity for the arterial branch patency among the three MRAs, ranged from 0.55 to 0.93, specificity from 0.61 to 0.68, positive predictive value from 0.79 to 0.93 and negative predictive value from 0.22 to 0.90.

CONCLUSIONS

Aneurysm occlusion, stent patency and arterial branch patency in flow diversion can be successfully evaluated with the combination of three MRA techniques.

Cost-Effective Analysis of Different Diagnostic Strategies in Screening for Aneurysms After Spontaneous Subarachnoid Hemorrhage

PURPOSE

With an increasing number of patients being treated by coiling for aneurysms, using computed tomographic angiography (CTA) or magnetic resonance angiography (MRA) as an initial screening test becomes less important because digital subtraction angiography (DSA) is the first step of endovascular treatment procedure. The objective of this study is to investigate whether CTA or MRA remained to be the optimal screening strategy in patients with spontaneous subarachnoid hemorrhage (SAH).

METHODS

CTA, MRA, and DSA strategy were evaluated in a decision tree model created with TreeAge Pro Suite 2011. Input parameters were derived from published literature and our institutional database. Base case and sensitivity analyses were conducted to assess the cost-effectiveness of each strategy. A Monte Carlo simulation was performed with all parameters ranged among their distributions to evaluate the validation of results.

RESULTS

The base case scenario showed that MRA was the most cost-effective strategy. Using a willingness-to-pay threshold of ¥70,892/quality adjusted life year, MRA remained to be most cost-effective when its sensitivity is >0.907. DSA was not cost-effective compared to CTA or MRA unless over 91.56% of patients were treated by coiling. The Monte Carlo simulation reported DSA not to be a cost-effective strategy at willingness-to-pay of ¥70,892 in 99.99% of the iterations.

CONCLUSION

DSA is not cost-effective compared to CTA or MRA and should not be used as the initial diagnostic tool for spontaneous SAH.

Therapeutic Approaches for Cerebrovascular Dysfunction After Aneurysmal Subarachnoid Hemorrhage: An Update and Future Perspectives

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe subtype of stroke occurring at a relatively young age with a significant socioeconomic impact. Treatment of aSAH includes early aneurysm exclusion, intensive care management, and prevention of complications. Once the aneurysm rupture occurs, blood spreading within the subarachnoid space triggers several molecular pathways causing early brain injury and delayed cerebral ischemia. Pathophysiologic mechanisms underlying brain injury after aSAH are not entirely characterized, reflecting the difficulties in identifying effective therapeutic targets for patients with aSAH. Although the improvements of the last decades in perioperative management, early diagnosis, aneurysm exclusion techniques, and medical treatments have increased survival, vasospasm and delayed cerebral infarction are associated with high mortality and morbidity. Clinical practice can rely on a few specific therapeutic agents, such as nimodipine, a calcium-channel blocker proved to reduce severe neurologic deficits in these patients. Therefore, new pharmacologic approaches are needed to improve the outcome of this life-threatening condition, as well as a tailored rehabilitation plan to maintain the quality of life in aSAH survivors. Several clinical trials are investigating the efficacy and safety of emerging drugs, such as magnesium, clazosentan, cilostazol, interleukin 1 receptor antagonists, deferoxamine, erythropoietin, and nicardipine, and continuous lumbar drainage in the setting of aSAH. This narrative review focuses on the most promising therapeutic interventions after aSAH.

Safety of pediatric cerebral angiography

OBJECTIVE

Catheter-based cerebral angiography is commonly used for neurovascular diagnosis in children. In this work, the authors aimed to quantify the complication rate of cerebral angiography in children, characterize these complications, and identify risk factors for complications.

METHODS

Relevant clinical data were retrospectively obtained for 587 consecutive cerebral angiography procedures performed in 390 children from March 2002 to March 2020. Complications were categorized as neurological or nonneurological, and severity was graded using a standard schema. Incidences of complications were reported as point estimates. Associations between risk factors and complications were characterized in univariate analysis using the two-tailed Fisher exact test and in multivariate analysis using multiple logistic regression with bidirectional elimination based on the Akaike information criterion. In both univariate and multivariate analyses, statistical significance was corrected for multiple comparisons using the Benjamini-Hochberg method.

RESULTS

Complications occurred in 6.5% of procedures, including neurological complications in 1.9% and nonneurological complications in 4.8%. Permanent deficits occurred in only 0.2% of cases. Overall, 0.5% of procedures resulted in major complications, while 6.0% resulted in minor complications. Female sex and a history of hypertension or ischemic stroke were associated with an increased risk of complications, while femoral artery access was associated with a decreased risk of complications.

CONCLUSIONS

Pediatric cerebral angiography was shown to have a low rate of major or permanent complications. Children who were female and those with a history of hypertension or ischemic stroke were shown to be at higher risk of complications, while the use of femoral access carried a lower risk of complications.

Safety of intra-arterial chemotherapy with or without osmotic blood–brain barrier disruption for the treatment of patients with brain tumors

Background

Intra-arterial administration of chemotherapy with or without osmotic blood–brain barrier disruption enhances delivery of therapeutic agents to brain tumors. The aim of this study is to evaluate the safety of these procedures.

Methods

Retrospectively collected data from a prospective database of consecutive patients with primary and metastatic brain tumors who received intra-arterial chemotherapy without osmotic blood–brain barrier disruption (IA) or intra-arterial chemotherapy with osmotic blood–brain barrier disruption (IA/OBBBD) at Oregon Health and Science University (OHSU) between December 1997 and November 2018 is reported. Chemotherapy-related complications are detailed per Common Terminology Criteria for Adverse Events (CTCAE) guidelines. Procedure-related complications are grouped as major and minor.

Results

4939 procedures (1102 IA; 3837 IA/OBBBD) were performed on 436 patients with various pathologies (primary central nervous system lymphoma [26.4%], glioblastoma [18.1%], and oligodendroglioma [14.7%]). Major procedure-related complications (IA: 12, 1%; IA/OBBBD: 27, 0.7%; P = .292) occurred in 39 procedures including 3 arterial dissections requiring intervention, 21 symptomatic strokes, 3 myocardial infarctions, 6 cervical cord injuries, and 6 deaths within 3 days. Minor procedure-related complications occurred in 330 procedures (IA: 41, 3.7%; IA/OBBBD: 289, 7.5%; P = .001). Chemotherapy-related complications with a CTCAE attribution and grade higher than 3 was seen in 359 (82.3%) patients.

Conclusions

We provide safety and tolerability data from the largest cohort of consecutive patients who received IA or IA/OBBBD. Our data demonstrate that IA or IA/OBBBD safely enhance drug delivery to brain tumors and brain around the tumor.

Factors determining outcome of post-angiogram-negative subarachnoid hemorrhage

Aim:

To determine the risk factors affecting outcome at the end of 90 days of post-angiogram-negative subarachnoid hemorrhage (SAH).

Methods:

Non-traumatic SAH cases were reviewed from the case records of patients who had reported to the Department of Neurology of a tertiary care hospital and 50 angio-negative SAH cases were included after excluding all the cases with known cause of hemorrhage after doing computed tomography angiography (CTA)/digital subtraction angiography (DSA). The presence of hypertension, diabetes mellitus, coronary artery disease (CAD), history of alcohol and smoking, and various scales like Hunt and Hess Scale (HHS), World Federation of Neurological Surgeons (WFNS), and Fisher scale had been recorded at admission. The outcome was assessed at 90 days post-SAH using the Modified Rankin Scale (mRS).

Statistical analyses:

The association between the outcome and the factors was assessed using the Pearson Chi-Square test and the risk factors/predictors of outcome were assessed using logistic regression.

Results:

The following variables were important risk factors for predicting poor outcome of angio-negative SAH (mRS 3 to 6): hypertension (P = 0.011), diabetes mellitus (P = 0.032), being an alcoholic (P = 0.019), HHS grade 4 to 5 (P < 0.01), and WFNS grade 4 to 5 (P < 0.01). On multivariate regression analysis, hypertension (P = 0.032) was an independent predictor of unfavorable outcome.

Conclusions:

At time of admission, presence of hypertension, diabetes mellitus, history of alcohol consumption, and poor grades of HHS and WFNS scale are predictors of poor outcome of angio-negative SAH.

Intravenous Milrinone for Cerebral Vasospasm in Subarachnoid Hemorrhage: The MILRISPASM Controlled Before-After Study

BACKGROUND

Intravenous (IV) milrinone, in combination with induced hypertension, has been proposed as a treatment option for cerebral vasospasm after aneurysmal subarachnoid hemorrhage (aSAH). However, data on its safety and efficacy are scarce.

METHODS

This was a controlled observational study conducted in an academic hospital with prospectively and retrospectively collected data. Consecutive patients with cerebral vasospasm following aSAH and treated with both IV milrinone (0.5 µg/kg/min^-1, as part of a strict protocol) and induced hypertension were compared with a historical control group receiving hypertension alone. Multivariable analyses aimed at minimizing potential biases. We assessed (1) 6-month functional disability (defined as a score between 2 and 6 on the modified Rankin Scale) and vasospasm-related brain infarction, (2) the rate of first-line or rescue endovascular angioplasty for vasospasm, and (3) immediate tolerance to IV milrinone.

RESULTS

Ninety-four patients were included (41 and 53 in the IV milrinone and the control group, respectively). IV milrinone infusion was independently associated with a lower likelihood of 6-month functional disability (adjusted odds ratio [aOR] = 0.28, 95% confidence interval [CI] = 0.10-0.77]) and vasospasm-related brain infarction (aOR = 0.19, 95% CI 0.04-0.94). Endovascular angioplasty was less frequent in the IV milrinone group (6 [15%] vs. 28 [53%] patients, p = 0.0001, aOR = 0.12, 95% CI 0.04-0.38). IV milrinone (median duration of infusion, 5 [2-8] days) was prematurely discontinued owing to poor tolerance in 12 patients, mostly (n = 10) for "non/hardly-attained induced hypertension" (mean arterial blood pressure < 100 mmHg despite 1.5 µg/kg/min^-1 of norepinephrine). However, this event was similarly observed in IV milrinone and control patients (n = 10 [24%] vs. n = 11 [21%], respectively, p = 0.68). IV milrinone was associated with a higher incidence of polyuria (IV milrinone patients had creatinine clearance of 191 [153-238] ml/min^-1) and hyponatremia or hypokalemia, whereas arrhythmia, myocardial ischemia, and thrombocytopenia were infrequent.

CONCLUSIONS

Despite its premature discontinuation in 29% of patients as a result of its poor tolerance, IV milrinone was associated with a lower rate of endovascular angioplasty and a positive impact on long-term neurological and radiological outcomes. These preliminary findings encourage the conduction of confirmatory randomized trials.

The role of noninvasive imaging in the diagnostic workup for pulsatile tinnitus

OBJECTIVE

We sought to assess the diagnostic yield of advanced noninvasive imaging in the evaluation of patients with pulsatile tinnitus.

BACKGROUND

Pulsatile tinnitus can be caused by high-risk cerebrovascular pathologies such as arteriovenous fistulae. The role of advanced noninvasive imaging, including magnetic resonance angiography and magnetic resonance venography, in the diagnostic evaluation of pulsatile tinnitus is not well defined.

DESIGN AND METHODS

We performed a retrospective cohort study of patients presenting for outpatient diagnostic evaluation of pulsatile tinnitus from January 2018 to March 2020 at Weill Cornell Medicine. Patients with non-pulsatile tinnitus and established etiologic diagnoses were excluded. Systematic chart abstraction was summarized using standard descriptive statistics. Univariate logistic regression was used to identify factors associated with nondiagnostic noninvasive imaging.

RESULTS

A total of 187 patients (139 (74.3%) women) took part in this study, with a mean age of 48.6 years (standard deviation (SD) = 15.5 years) and a mean body mass index (BMI) of 26.9 kg/m² (SD = 6.1 kg/m²). Of the 187 patients, 121 (64.7%) underwent exclusively noninvasive imaging, and 66 (35.3%) patients also had digital subtraction angiography (DSA). In patients who had exclusively noninvasive imaging, 62 (51.2%) patients received a diagnosis. In patients who underwent noninvasive and DSA imaging, 14 (21.2%) patients received a diagnosis based on DSA. Patients who were older at symptom onset (odds ratio (OR) = 1.05; 95% confidence interval (CI) 1.01-1.09) and those with a lower BMI (OR = 0.88, 95% CI 0.77-0.98) were more likely to have nondiagnostic noninvasive imaging.

CONCLUSION

Noninvasive cerebrovascular imaging often uncovers the etiology of pulsatile tinnitus. DSA remains useful for additional evaluation for patients with specific associated features.

Knowledge framework and emerging trends in intracranial aneurysm magnetic resonance angiography: a scientometric analysis from 2004 to 2020

Background

As magnetic resonance angiography (MRA) has been increasingly used in the follow-up of intracranial aneurysms (IAs) as a non-invasive technique, the knowledge framework and areas of research interest in intracranial aneurysms magnetic resonance angiography (IAMRA) change approximately every 10 years. However, few studies have quantitatively analyzed the published literature in this field. In the present study, we used scientometrics to survey the knowledge field, development trends, and research focus of IAMRA with the aim of providing a reference for further study.

Methods

We collected articles on IAMRA published from 2004 (Jan 1, 2004) to 2020 (May 24, 2020). Web of Science Core Collection databases (WoSCCd) including the Science Citation Index Expanded were searched. An experienced staff member from the Department of Radiology at Southern Medical University, assisted in screening articles for relevant articles. We used ArcGIS (a mapping and location analytics platform) to perform geographic visualization. Excel 2016 was used to analyze the literature data, including number of publications, impact factor (IF), and publication year. CiteSpace V was used to conduct a series of literature feature clustering, including author co-citation analysis, reference co-citation analysis (RCA), and burst keywords analysis.

Results

A total of 1,272 articles on IAMRA published between 2004 and 2020 were included. Of 257 journals, American Journal of Neuroradiology (IF 2018: 3.256) published the most IAMRA articles (109 publications, 8.57%), followed by Journal of Neurosurgery (IF 2018: 4.131, 51 publications, 4.16%), and Neuroradiology (IF 2018: 2.504, 51 publications, 4.01%). Of 56 countries, the USA published the most, with 347 articles [27.28%, IF: 3.14 (average IF of all journals in the country)], followed by Japan (242 articles, 19.03%, IF: 2.38), Germany (135 articles, 10.61%, IF: 3.21), and China (101 articles, 7.94%, IF: 2.86). A total of 1387 institutions published articles, with the Mayo Clinic publishing the most (33 articles, 2.59%), followed by Shanghai Jiao Tong University (25 article, 1.97%), Seoul National University (23 articles, 1.81%), and University Medical Center Utrecht (19 articles, 1.49%). Of 399 authors, Rinkel ranked first with 19 articles, followed by Li MH (18 articles), Uchino A (15 articles), and Saito N (13 articles). Cluster RCA showed that the first cluster was "#0 growth", followed by "#1 Guglielmi detachable coils". Timeline views showed that the time span of "#0 growth" was the closest to today. The modularity value was 0.6971, and the mean silhouette value was 0.5477. According to the burst keyword analysis, "risk factors associated to rupture" was the topic with the strongest burst since 2017. Studies conducted in several countries suggested that age is inversely related to the risk of rupture, which implies the importance of MRA follow-up for patients of different age.

Conclusions

From 2004 to 2020, the number of published IAMRA-related articles gradually increased. The USA and Western Europe lead in the field, with a concentration of cutting-edge talents and high-level scientific research institutions. A synthesis of the clustering results of RCA and burst keyword analysis indicated that unruptured IA growth, stent-assisted coil embolization, and risk factors associated to rupture were the current hotspots in IAMRA research.