Complications of Modern Diagnostic Cerebral Angiography in an Academic Medical Center

Imaging of Intracranial Aneurysms: A Review of Standard and Advanced Imaging Techniques

The treatment of intracranial aneurysms is dictated by its risk of rupture in the future. Several clinical and radiological risk factors for aneurysm rupture have been described and incorporated into prediction models. Despite the recent technological advancements in aneurysm imaging, linear length and visible irregularity with a bleb are the only radiological measure used in clinical prediction models. The purpose of this article is to summarize both the standard imaging techniques, including their limitations, and the advanced techniques being used experimentally to image aneurysms. It is expected that as our understanding of advanced techniques improves, and their ability to predict clinical events is demonstrated, they become an increasingly routine part of aneurysm assessment. It is important that neurovascular specialists understand the spectrum of imaging techniques available.

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.

National trends in catheter angiography and cerebrovascular imaging in a group of privately insured patients in the US

BACKGROUND

Despite the increasing use of non-invasive imaging, DSA remains the gold standard for cerebrovascular imaging. However, trends in DSA utilization are poorly understood. The goal of this study was to describe DSA utilization in a large claims database in the US over a 13 year period.

METHODS

This retrospective cohort study assessed a nationwide database of privately insured individuals from 2005 to 2018 for patients undergoing cranial CT angiography (CTA), MR angiography (MRA), and DSA. We assessed trends in the overall use of and indications for each modality. For DSA, we examined the types of performing proceduralists.

RESULTS

Among patients undergoing DSA in 2018, median age was 52 years, and 60% were women. MRA and DSA use decreased, from 289 to 275 claims, and from 38 to 29 claims per 100 000 enrollees, respectively, while CTA use increased from 31 to 286 claims per 100 000 enrollees. These trends differed by geographic region and indication. Nearly half of DSA procedures but <25% of non-invasive imaging were inpatient studies. DSA performed by neurosurgeons increased from 0.5 to 4.1 while those performed by radiologists decreased from 7.2 to 4.0 studies per 100 000 enrollees.

CONCLUSIONS

DSA use decreased slightly while CTA use increased by ninefold. The reasons for this change are likely complex and may reflect more aggressive imaging for stroke, increased detection of incidental findings, and increased quality of non-invasive imaging. Over time, the proportion of DSA procedures performed by neurosurgeons overtook that performed by radiologists.

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.

Use of diagnostic subtraction angiography for ischemic stroke (US DUTCH study) Regional variation and time-trend among medicare beneficiaries

INTRODUCTION

There are no guideline recommendations for DSA in the ischemic stroke work-up. We studied the rate of DSA in ischemic stroke, the recent time-trend, hospital variation and associated factors.

METHODS

This is a retrospective cross-sectional study among Medicare fee-for-service beneficiaries with ischemic stroke admitted between 2016 and 2020 in the United States. ICD-10 codes were used to determine ischemic stroke diagnosis and procedure codes for thrombectomy and DSA. Hospital trends and factors associated with DSA performance were analyzed in hospitals with DSA capacity.

RESULTS

7.373 (0.7 %) of the 1,085,644 ischemic stroke patients, had a DSA for diagnostic purposes. In the patients that were admitted to a hospital with DSA facility, the following factors showed the strongest association with DSA: younger age (aOR=0.81 [95 % confidence interval (CI):0.81-0.83]), thrombectomy rate in that hospital (aOR=2549 [95 %CI:610-10663]), transfer (aOR=1.41[95 %CI:1.34-1.50]) and carotid disease (aOR=5.8 [95 %CI:5.6-6.1]). There was large variation in the hospital DSA rate, varying from 0.07 % to 11.1 %. Of the variance of DSA rates, 15 % was attributed to the residual effect hospital propensity to perform DSA. The top decile of hospitals with the highest DSA rate, performed DSA's in >2.3 % of patients, compared to the 0.6 % median. There was no change in DSA rates over time.

CONCLUSION

DSA is used infrequently in acute ischemic stroke patients and did not change between 2016 to 2020. Hospital variation in DSA use was however large, and not solely explained by patient and facility factors.

Sensitivity of the Unruptured Intracranial Aneurysm Treatment Score (UIATS) to detect aneurysms at high-risk of rupture: Retrospective analysis in a cohort of 346 patients with a proven subarachnoid hemorrhage

INTRODUCTION

The aim of this study was to assess the capability of the Unruptured Intracranial Aneurysm Treatment Score (UIATS) to discriminate unruptured intracranial aneurysms (UIAs) at high risk for subarachnoid hemorrhage (aSAH).

MATERIAL AND METHOD

During the period from January 2012 to December 2022, we included all consecutive adult patients admitted to our institution for an aSAH caused by the rupture of a saccular IA. The patient-related, aneurysm-related and treatment-related risk factors considered by UIATS were retrieved from medical records. After UIATS calculation for all ruptured IAs in the cohort, patients were categorized as "true positives (TP)" if UIATS would have (appropriately) oriented the management toward treatment, whereas patients for whom the UIATS would have (inappropriately) recommended observation were categorized as "false negatives (FN)". Patients for whom UIATS was inconclusive were categorized as "undetermined (UND)". Sensitivity of the UIATS (Se UIATS) was calculated by using the following formula: TP/(TP + FN).

RESULTS

A total of 346 patients (253 women, 73%; mean age = 56 ± 1.45 years) were incorporated into the final analysis. There were 140 T P (40%), 79 F N (23%) and 127 UND (37%), leading to a Se UIATS of 63.9% (CI 58.3-69.5). Cumulatively, the UIATS failed to provide an appropriate recommendation in 60% of the entire cohort.

CONCLUSION

By retrospectively applying the UIATS in a cohort of ruptured IAs, our study emphasizes how vulnerable the UIATS can be. Even if the UIATS suggests conservative management, clinicians should inform patients that there is still a small risk of rupture.

Follow-Up Imaging in Angiography-Negative Spontaneous Subarachnoid Hemorrhage

BACKGROUND

The aim of this study was to assess the diagnostic yield of follow-up investigations in aneurysm-negative subarachnoid hemorrhage (SAH) patients.

METHODS

In 109 (25%) of 435 patients with SAH and initial negative digital subtraction angiography (DSA), the diagnostic yield of repeat DSA and magnetic resonance imaging (MRI) of the brain and craniocervical junction was reviewed.

RESULTS

Of the 109 patients with an initial negative DSA, 51 (47%) had perimesencephalic (PM), 54 (50%) had nonperimesencephalic (NPM) blood distribution, and 4 (3.7%) had computed tomography-negative SAH. A delayed bleeding source was determined in 3 of 82 (3.7%) patients who underwent repeat DSA and in 1 of 5 patients who underwent a third DSA. The bleeding patterns of these patients were all NPM (n = 4). Repeat DSA did not identify a bleeding source in patients with PM-SAH. MRI of the brain and craniocervical junction after 2 days revealed a bleeding source in 1 of 105 patients (1%) in a computed tomography-negative SAH. When all diagnostic modalities, including exploratory craniotomy and MRI of the spinal axis, were considered, the rate of delayed diagnosis of the bleeding source was 6.4% (7/109). In addition to the bleeding pattern, patients with delayed diagnosis of the bleeding source were characterized by worse disease severity parameters, worse radiological grading scales, and more in-hospital complications than patients without delayed diagnosis of a bleeding source.

CONCLUSIONS

The results of this study support the use of repeat DSA in patients with NPM-SAH; however, routine repeat DSA may not be indicated in PM-SAH patients. The routine use of MRI remains controversial.

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.

Safety Aspects and Procedural Characteristics of Ambulatory Diagnostic Cerebral Catheter Angiography

PURPOSE

Diagnostic cerebral catheter angiography is used to assess a variety of neurovascular pathologies especially in patients before and after endovascular neurointerventional treatment. In many centers diagnostic cerebral angiographies are performed with the patient staying for one night in the hospital because there are not yet sufficient data on the safety of ambulatory cerebral angiography. At the same time hospitals face a growing demand to perform ambulatory medical procedures.

METHODS

A total of 426 ambulatory diagnostic cerebral angiographies were retrospectively analyzed. Technical details of the angiographies were analyzed to identify procedural risk factors.

RESULTS

Out of 426 patients 14 (3.3%) had some form of complication, 3 developed minor transient neurological symptoms, 1 patient developed Quincke's edema probably as an adverse reaction to contrast agent, 1 patient had an asymptomatic carotid dissection and 1 had a fall of unknown etiology. Of the 14 complications 8 were puncture site complications with 1 re-bleeding, 1 dissection, and 6 minor complications, 421 punctures were femoral, 3 radial and 2 brachial. Out of 333 patients with magnetic resonance imaging (MRI) after angiography 21 showed focal diffusion-weighted imaging (DWI) lesions but none of these lesions were symptomatic. The rate of DWI lesions was significantly higher in selectively angiography territories than in other territories. The use of a Simmons 2 catheter significantly increased the rate of DWI lesions (p = 0.047), whereas 3D rotational angiography did not (p = 0.55). The rate of DWI lesions per selectively accessed vessel was 4.6% with a higher rate in the anterior than in the posterior circulation.

CONCLUSION

Diagnostic cerebral catheter angiography can be safely performed in an ambulatory setting.

Assessment of Blood Loss during Neuroendovascular Procedures

(1) Background: Neuroendovascular procedures have generally been considered to have minor or inconsequential blood loss. No study, however, has investigated this question. The purpose of this study is to quantify the blood loss associated with neuroendovascular procedures and identify predictors of blood loss, using hemoglobin change as a surrogate for blood loss. (2) Methods: A retrospective review of 200 consecutive endovascular procedures (diagnostic and therapeutic) at our institution from January 2020 to October 2020 was performed. Patients had to have pre- and post-operative hematocrit and hemoglobin levels recorded within 48 h of the procedure (with no intervening surgeries) for inclusion. (3) Results: The mean age of our cohort was 60.1 years and the male representation was 52.5%. The mean pre-operative hemoglobin/hematocrit was significantly lower among females compared to males (12.1/36.2 vs. 13.0/38.5, p = 0.003, p = 0.009). The mean hemoglobin decrease was 0.5 g/dL for diagnostic angiograms compared to 1.2 g/dL for endovascular interventions (p < 0.0001), and 1.0 g/dL for all procedures combined. In a multivariate linear regression analysis, pre-operative antiplatelet/anticoagulant use was associated with a statistically significant decrease in hemoglobin. (4) Conclusions: Our data support that blood loss from diagnostic angiograms is marginal. Blood loss in endovascular interventions, however, tends to be higher. Pre-operative blood antiplatelet/anticoagulant use and increasing age appear to increase bleeding risk and may require closer patient monitoring.

Imaging modality-dependent carotid stenosis severity variations against intravascular ultrasound as a reference: Carotid Artery intravasculaR Ultrasound Study (CARUS)

PURPOSE

Different non-invasive and invasive imaging modalities are used to determine carotid artery stenosis severity that remains a principal parameter in clinical decision-making. We compared stenosis degree obtained with different modalities against vascular imaging gold standard, intravascular ultrasound, IVUS.

METHODS

300 consecutive patients (age 47-83 years, 192 men, 64% asymptomatic) with carotid artery stenosis of " ≥ 50%" referred for potential revascularization received as per study protocol (i) duplex ultrasound (DUS), (ii) computed tomography angiography (CTA), (iii) intraarterial quantitative angiography (iQA) and (iv) and (iv) IVUS. Correlation of measurements with IVUS (r), proportion of those concordant (within 10%) and proportion of under/overestimated were calculated along with recipient-operating-characteristics (ROC).

RESULTS

For IVUS area stenosis (AS) and IVUS minimal lumen area (MLA), there was only a moderate correlation with DUS velocities (peak-systolic, PSV; end-diastolic, EDV; r values of 0.42-0.51, p < 0.001 for all). CTA systematically underestimated both reference area and MLA (80.4% and 92.3% cases) but CTA error was lesser for AS (proportion concordant-57.4%; CTA under/overestimation-12.5%/30.1%). iQA diameter stenosis (DS) was found concordant with IVUS in 41.1% measurements (iQA under/overestimation 7.9%/51.0%). By univariate model, PSV (ROC area-under-the-curve, AUC, 0.77, cutoff 2.6 m/s), EDV (AUC 0.72, cutoff 0.71 m/s) and CTA-DS (AUC 0.83, cutoff 59.6%) were predictors of ≥ 50% DS by IVUS (p < 0.001 for all). Best predictor, however, of ≥ 50% DS by IVUS was stenosis severity evaluation by automated contrast column density measurement on iQA (AUC 0.87, cutoff 68%, p < 0.001). Regarding non-invasive techniques, CTA was the only independent diagnostic modality against IVUS on multivariate model (p = 0.008).

CONCLUSION

IVUS validation shows significant imaging modality-dependent variations in carotid stenosis severity determination.

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).

Subarachnoid haemorrhage associated with pituitary apoplexy and radiographically occult supraclinoid internal carotid artery aneurysms

In patients with pituitary adenomas, incidental intracranial aneurysms have been documented. Previous studies have highlighted the importance of preoperative imaging in these patients. However, imaging may be limited and fail to show the presence of vascular abnormalities. In this report, we discuss a case of a man in his 30s presenting with a newly diagnosed pituitary adenoma. CT and MRI, on admission, showed a pituitary mass with extension into the right cavernous sinus. After a sudden neurological deterioration, emergent CT/CT angiography revealed pituitary apoplexy with subarachnoid extension without vascular abnormalities. Successful emergency transsphenoidal hypophysectomy was followed by digital subtraction angiography which revealed the presence of two right supraclinoid internal carotid artery aneurysms. With this case, we aim to highlight the need for further vascular imaging in patients with pituitary apoplexy and subarachnoid haemorrhage, as preoperative imaging may be negative for vascular abnormalities especially in the setting of cavernous sinus invasion.

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.

The impact of Verapamil for radial access in diagnostic cerebrovascular angiograms: A retrospective case-control study

INTRODUCTION

Different combinations of medications are utilized during wrist access for radial artery (RA) or ulnar artery (UA) catheterization in neuroendovascular procedures to preclude vasospasm. These "cocktails" commonly include the calcium channel blocker Verapamil, without established benefit. We analyze outcomes in patients with and without Verapamil in their "cocktail" by using a case-control cohort of our single-center experience.

METHODS

A prospective log of consecutive patients who underwent diagnostic cerebral angiograms using RA/UA access was retrospectively reviewed, and patients were grouped into Verapamil and non-Verapamil cohorts. The primary outcomes assessed were the presence of forearm skin rashes (hives) and RA/UA spasms. Our initial management included Verapamil (5 mg) in the cocktail, but Verapamil was removed after we noticed the development of hives in multiple patients immediately following its injection.

RESULTS

A total of 221 patients underwent 241 RA/UA diagnostic cerebral angiograms and were included in our analysis. One hundred and forty-nine patients (61.8%) underwent catheterization with Verapamil and 92 (38.2%) were catheterized without it. Four of the 149 patients in the Verapamil group (2.7%) developed hives during the procedure and were treated with Benadryl (25 mg). Of the 92 patients who did not receive Verapamil, there were zero (0%) cases of hives and one (1.1%) case of vasospasm.

CONCLUSION

Verapamil in the "cocktail" for wrist access diagnostic cerebral angiograms was associated with periprocedural hives, but not associated with a significant reduction in spasm compared to the non-Verapamil group. Our findings suggest that the administration of prophylactic Verapamil for these procedures may not be necessary.

Precision Delivery of Steroids as a Rescue Therapy for Gastrointestinal Graft-versus-Host Disease in Pediatric Stem Cell Transplant Recipients

Graft versus host disease (GVHD) is one of the most serious complications following stem cell transplant in children and is a major cause of morbidity and mortality. Corticosteroids remain the mainstay of treatment, and although a majority of children respond to systemic steroids, those refractory to or dependent upon corticosteroids suffer from complications secondary to long-term steroid administration. This problem has prompted consideration of steroid-sparing treatment strategies, although the time to clinical remission can be variable. Intraarterial corticosteroid delivery has been used in adults as a rescue therapy in steroid-resistant patients, but its use in children has been limited. We investigated the feasibility of intraarterial steroid administration into the bowel and/or liver in a cohort of six pediatric patients with acute GVHD. All patients successfully underwent treatment with no serious adverse effects. Five of five (100%) patients with gastrointestinal bleeding due to GVHD had rapid symptom improvement by 48 h, which was durable up to three weeks. Three of four (75%) patients with hepatic GVHD had improved cholestasis following intraarterial steroid administration. Our experience with this small cohort preliminarily demonstrated the feasibility and safety of intraarterial steroid administration in children with acute GVHD. This approach warrants consideration as a rescue therapy in steroid-refractory cases and as a "bridge" therapy for children with severe acute GVHD who are transitioning to steroid-sparing regimens.

Four French sheath-based transradial cerebral angiographies in the elderly: A single neurointerventionalist's experience

BACKGROUND

Catheter angiography via transradial access (TRA) is better at reducing access site complications and morbidity than via transfemoral access (TFA). The rate of periprocedural complications increases in elderly populations and using a smaller sheath can help reduce access site complications. The aim of this study was to assess the feasibility and safety of 4 F sheath-based TRA cerebral angiography in elderly patients (≥65 years) and compare it to TFA cerebral angiography.

METHODS

The medical records of elderly patients undergoing diagnostic cerebral angiography with a single neurointerventionalist via TRA (57 cases, from July 2019 to December 2020) versus TFA (69 cases, from January 2018 to June 2019) were retrospectively reviewed. All TRA angiographies were performed via right radial artery access with a 4 F sheath and a 4 F Simmons 2 catheter.

RESULTS

There were no significant differences (TRA vs. TFA) in age (71.1 ± 4.0 vs. 72.1 ± 4.6 years, p = 0.189), accessed vessels (3.9 ± 0.5 vs. 3.9 ± 0.6, p = 0.852), fluoroscopy time (7.1 ± 3.3 vs. 7.6 ± 3.5 min, p = 0.068), and radiation exposure (42.1 ± 15.8 vs. 47.0 ± 13.7 Gy-cm2, p = 0.067). However, the procedure duration was significantly shorter in the TRA group (17.2 ± 3.9 vs. 19.0 ± 6.0 min, p = 0.003). Painful groin hematoma occurred in 2 of the 69 cases (2.9%) in the TFA group. In the TRA group, access site complications were not occurred; however, catheter kinks occurred in 2 of 57 cases (3.5%).

CONCLUSIONS

The 4 F sheath-based TRA is a feasible option for diagnostic cerebral angiography in elderly patients. However, care should be taken during catheter manipulation.

Case Series of Precision Delivery of Methylprednisolone in Pediatric Inflammatory Bowel Disease: Feasibility, Clinical Outcomes, and Identification of a Vasculitic Transcriptional Program

Systemic steroid exposure, while useful for the treatment of acute flares in inflammatory bowel disease (IBD), is associated with an array of side effects that are particularly significant in children. Technical advancements have enabled locoregional intraarterial steroid delivery directly into specific segments of the gastrointestinal tract, thereby maximizing tissue concentration while limiting systemic exposure. We investigated the feasibility of intraarterial steroid administration into the bowel in a cohort of nine pediatric patients who had IBD. This treatment approach provided symptom relief in all patients, with sustained relief (>2 weeks) in seven out of nine; no serious adverse effects occurred in any patient. In addition, we identified patterns of vascular morphologic changes indicative of a vasculopathy within the mesenteric circulation of inflamed segments of the bowel in pediatric patients with Crohn's disease, which correlated with disease activity. An analysis of publicly available transcriptomic studies identified vasculitis-associated molecular pathways activated in the endothelial cells of patients with active Crohn's disease, suggesting a possible shared transcriptional program between vasculitis and IBD. Intraarterial corticosteroid treatment is safe and has the potential to be widely accepted as a locoregional approach for therapy delivery directly into the bowel; however, this approach still warrants further consideration as a short-term "bridge" between therapy transitions for symptomatic IBD patients with refractory disease, as part of a broader steroid-minimizing treatment strategy.

Complications and risk factors after digital subtraction angiography: 1-year single-center study

OBJECTIVE

Digital subtraction angiography (DSA) is an imaging technique used to diagnose and confirm abnormal lesions of cerebral blood vessels in various situations. Several complications such as cerebral infarction, contrast-induced allergy, and angio-site hematoma or infection can occur after DSA. We investigated complication rates and risk factors related to DSA.

METHODS

All patients who underwent DSA at Incheon St. Mary's Hospital from January to December 2021 were included. Those who underwent emergency DSA due to stroke or who underwent endovascular surgery within 1 week after DSA were excluded. Complications that occurred within 1 week after DSA were included in the study and was classified into three categories (neurologic complications, contrast-induced allergy, and wound complications).

RESULTS

The mean age was 57.7±13.2 years old and the female was dominant at 63.9%. The overall complication rate was 5% (n=20/407). Regarding neurologic complications, the presence of malignancy (p<0.01), and a longer procedure time (>15 minutes, p=0.04) were statistically significant factors. Contrast-induced allergy did not show any statistically significant difference in any parameter. The wound complication rate was higher in men (p=0.02), trans-femoral approach (p=0.02), frequent alcohol drinkers (p=0.04), those taking anticoagulants (p=0.03), and longer procedure time (>15 minutes, p<0.01).

CONCLUSIONS

DSA is an invasive diagnostic modality and can cause several complications. Patients with cancer should be more careful about the occurrence of cerebral infarction, and men taking anticoagulants or drinking frequently should be more careful about the occurrence of angio-site hematomas.

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.

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.

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.

Artificial intelligence software for diagnosing intracranial arterial occlusion in patients with acute ischemic stroke

PURPOSE

To evaluate the diagnostic performance of AI software in diagnosing intracranial arterial occlusions in the proximal anterior circulation at CT angiography (CTA) and to compare it to manual reading performed in clinical practice.

METHODS

Patients with acute ischemic stroke underwent CTA to detect arterial occlusion in the proximal anterior circulation. Retrospective review of CTA scans by two neuroradiologists served as reference standard. Sensitivity and specificity of AI software (StrokeViewer) were compared to those of manual reading using the McNemar test. The proportions of correctly detected occlusions in the distal internal carotid artery and/or M1 segment of the middle cerebral artery (large vessel occlusion [LVO]) and in the M2 segment of the middle cerebral artery (medium vessel occlusion [MeVO]) were calculated.

RESULTS

Of the 474 patients, 75 (15.8%) had an arterial occlusion in the proximal anterior circulation according to the reference standard. Sensitivity of StrokeViewer software was not significantly different compared to that of manual reading (77.3% vs. 78.7%, P = 1.000). Specificity of StrokeViewer software was significantly lower than that of manual reading (88.5% vs. 100%, P < 0.001). StrokeViewer software correctly identified 40 of 42 LVOs (95.2%) and 18 of 33 MeVOs (54.5%). StrokeViewer software detected 8 of 16 (50%) intracranial arterial occlusions which were missed by manual reading.

CONCLUSION

The current AI software detected intracranial arterial occlusion with moderate sensitivity and fairly high specificity. The AI software may detect additional occlusions which are missed by manual reading. As such, the use of AI software may be of value in clinical stroke care.

Acute StrokeTreatment in Children: Are Adult Guidelines Applicable?

Purpose of this Review

This article provides an overview into acute treatments in stroke which are widely studied and available for adults and their applicability in the pediatric population.

Recent Findings

Arterial ischemic stroke is an important cause of morbidity and mortality in the pediatric population. Neurological deficits and etiologies are age-dependent and more challenging to diagnose than in the adult population. Advancements in imaging and treatment modalities including increased treatment windows in acute stroke have led to improvement in the diagnosis and management of pediatric arterial ischemic disease. Accordingly, hyperacute treatments, such as endovascular therapy, are becoming increasingly available in an attempt to improve outcomes in children.

Summary

Significant scientific and technological advances have transformed the hyperacute treatment of stroke in the recent years, allowing for improvement in the diagnosis and treatment of cerebrovascular pathologies in children. Optimization in the approach, and validation of existing stroke pathways/protocols is expected to further advance acute stroke therapy in pediatric patient care. Given that the lifelong individual, family, and societal burden of acute stroke is likely to be greater than in adults because infants and children surviving stroke live more years with disability, we must be knowledgeable about this pathology and the medical and therapeutic options available for this unique population as detailed in this review.

The utility of dual-energy computed tomography angiography for the evaluation of brain aneurysms after endovascular coiling: a prospective study

BACKGROUND

Non-invasive alternatives to digital subtraction angiography (DSA) for follow-up of patients with coiled aneurysms are sought.

PURPOSE

To compare a novel method of dual-energy computed tomography angiography (DE-CTA) for postoperative assessment of coiled brain aneurysms to detect aneurysm recanalization and patency of adjacent blood vessels, with DSA.

MATERIAL AND METHODS

Patients who underwent endovascular cerebral aneurysm coiling were prospectively evaluated postoperatively by both DE-CTA and conventional DSA. CTA was performed using a novel dual-energy method with single-source and fast kilovoltage switching. DSA was performed using biplanar cerebral angiography. An experienced neuroradiologist and neurosurgeon, both blinded to the original radiological results, reviewed the images.

RESULTS

A total of 54 patients (16 men, 38 women; mean age=47.6 + 9 years) with 55 coiled aneurysms were enrolled in our study between July 2014 and June 2015: 29 patients had suffered a subarachnoid hemorrhage and 26 patients had an incidentally found cerebral aneurysm. All patients had at least one DSA and DE-CTA performed at most one week apart. DE-CTA showed a 100% sensitivity and specificity in detection of complete aneurysm occlusion and 80% sensitivity and specificity for detection of residual necks and domes. DE-CTA successfully detected all vascular diameter changes as comparable to DSA with minimal interfering artifact.

CONCLUSION

DE-CTA is a promising non-invasive alternative to conventional catheter-based angiography for identification of aneurysm recurrence and assessment of adjacent arteries after endovascular coiling. It allows for far more rapid image acquisition than DSA, is non-invasive, and is widely available at clinical centers.

Dual-phase contrast-enhanced CT evaluation of dural arteriovenous fistula in patients with pulsatile tinnitus as an initial symptom

PURPOSE

Intracranial dural arteriovenous fistula (DAVF) can cause pulsatile tinnitus (PT). The purpose of this study was to investigate the diagnostic performance of dual-phase contrast-enhanced CT (DP-CECT) for DAVF in PT patients compared with digital subtraction angiography (DSA).

METHOD

From February 2015 to April 2021, PT patients undergoing routine DSA examination were prospectively analyzed. Patients with and without DAVF diagnosed by DSA were included. In DP-CECT, the radiological signs related to DAVF were assessed as follows: asymmetric external carotid artery (ECA) branches, asymmetric enhancement of intracranial or extracranial veins, asymmetric venous collaterals in extracranial space, and shaggy tentorium or venous sinus on CTA; asymmetric enhancement of intracranial or extracranial veins on CTV; numerous transcalvarial channels and asymmetric size of foramen spinosum on high-resolution CT (HRCT).

RESULTS

253 PT patients receiving DSA were enrolled, and these patients had previously been screened by DP-CECT. Forty-six patients were diagnosed as DAVF by DSA. Therefore, the prevalence of DAVF was 18% (46/253) in patients with PT as the initial symptom. The sensitivity and specificity of DP-CECT for diagnosis of DAVF were 96% and 100%. The sensitivity of individual CTA signs ranged from 65% to 93%, and specificities ranged from 83% to 100%. The sensitivity of CTV sign was 80%, and specificity was 100%. The sensitivity of individual HRCT signs ranged from 48 to 52% and specificities from 61 to 100%.

CONCLUSIONS

DAVF is not rare in patients with PT as the initial symptom. DP-CECT can be used for screening DAVF in patients with PT.

Clinical Outcome in Cerebral Vasospasm Patients Treated with and without Intra-Arterial Nimodipine Infusion

BACKGROUND

 Cerebral vasospasm (CV) after aneurysmal subarachnoid hemorrhage (aSAH) is still a problem. Hypertension, hypervolemia, and hemodilution (triple-H) therapy and oral nimodipine only a modest effect on patients. Intra-arterial treatment, including nimodipine, has been studied, but only as retrospective and single-arm prospective studies. We compared the outcomes between CV patients who received an adjunct intra-arterial nimodipine infusion (IANI) and those who received the standard medical treatment alone in a prospective randomized controlled trial.

METHODS

 In this study, patients between the age of 18 and 80 years, who underwent angiography within 14 days after aneurysm obliteration, were recruited and randomized to receive adjunct IANI or not, if they were identified with angiographic vasospasm. All the angiographic and neurologic data were recorded and analyzed during their admission, at the discharge date, and during the 6-month follow-up period.

RESULTS

 From June 2016 to December 2018, we enrolled 68 patients who were randomized into two groups, 36 in the intervention group and 32 in the control group. The patients' characteristics, aneurysm data, and modalities of treatment were similar between the two groups. Within 24 hours after IANI, Glasgow Coma Scale (GCS) score and motor strength revealed a significant improvement of 33.33 and 38.89%, respectively, in the intervention group versus 12.5 and 9.38%, respectively, in the control group. At discharge, the intervention group still had significant motor improvement (58.33 vs. 21.88%; p = 0.002).

CONCLUSION

 IANI could be considered an effective treatment for CV without significant complications. This is the first RCT demonstrating statistically significant motor strength improvement within 24 hours and at discharge.

Transcranial Doppler findings in a population with clinical probable reversible cerebral vasoconstriction syndrome

OBJECTIVE

To describe transcranial Doppler (TCD) findings in a population with clinical probable RCVS. Exploratory objectives included the study of clinical characteristics of probable RCVS patients with and without spasm detected by TCD.

METHODS

Cross-sectional cohort study of patients with thunderclap headache (TCH) without subarachnoid hemorrhage (SAH) of our neurology and headache center between 2010 and 2019, selecting patients with clinical diagnosis of probable RCVS (negative angiography study) by ICHD-3 criteria and with at least two TCD studies.

RESULTS

From 114 TCH patients, 36/114 had probable RCVS by ICHD-3 criteria and had at least two TCD studies available. The mean age at RCVS onset was 42.9years (21-72years); 29/36 (80.6%) were female, 7/28 (25%) had cardiovascular risk factors and 20/36 (55.6%) had history of migraine. Most common triggers were stressful emotion, drugs, valsalva maneuvers and sexual activity. Five/36 (13.9%) had complications and 3/36 (8.3%) had late recurrence. Initial TCD was performed on average of 16 (6-26) days after headache onset. Twenty-nine had vasospasm on TCD, presenting mean flow velocity of MCA (VMCA) of 135.7±17.0cm/s and mean maximum VMCA of 138.3±17.2. Vasospasm was mild in 21/29 patients (72.4%) and moderate in 8/29 (27.6%). Complete VMCA normalization occurred on average 41 (30-70) days after headache onset and 24 (11-47) days after initial TCD. The group of patients with vasospasm detected by TCD had more female patients (26/29, 89.7% vs. 3/7, 42.8%, P=0.016), and more TCH attacks (mean of 3.6 vs. 2.14, P=0.049).

CONCLUSION

TCD may be a useful tool in the identification of vasospasm in patients with probable RCVS, supporting the diagnosis of RCVS in patients presenting with recurrent TCH without SAH.

Ischaemic brain changes associated with catheter-based diagnostic cerebral angiography: a diffusion-weighted imaging study

Purpose

This study aims to evaluate the incidence of clinically silent embolic cerebral infarctions and associated risk factors following diagnostic cerebral angiography with diffusion-weighted imaging (DWI).

Material and methods

A total of 71 cerebral digital subtraction angiograms (42 male, 29 female, average age: 56.0 ± 15.0) obtained using nonionic contrast material were prospectively evaluated. To assess embolic events, before and after (1-3 days) angiography, DWI was performed. The risk factors for embolic ischemic brain changes such as the patient’s age and sex, atherosclerotic vessel wall disease, type of indication for catheter angiography, the number and size of the catheters, anatomic variants, selective/nonselective catheterization, contrast media volume, and time of procedure were determined. Fisher’s exact tests and Student t-tests were used for the statistical analyses of outcomes.

Results

Thirteen new silent ischemic lesions were identified in 7 out of 71 patients who underwent diagnostic cerebral angiography. Embolic cerebral lesions were often 6-10mm in diameter. According to the findings in this study, there was a strong correlation between diffusion abnormality and patient age, which was considered risk factors (p < 0.05). However, there were no significant correlations between other risk factors and the lesions’ appearance (p > 0.05).

Conclusions

In elderly patients, the angiographic procedures should be performed meticulously and DWI in all patients obtained routinely, even if the regular neurological examination shows they are healthy. In this way, the presence of microemboli and clinical results can be evaluated.

A comparison of radial versus femoral artery access for acute stroke interventions

OBJECTIVE

In this study, the authors aimed to investigate procedural and clinical outcomes between radial and femoral artery access in patients undergoing thrombectomy for acute stroke.

METHODS

The authors conducted a single-institution retrospective analysis of 104 patients who underwent mechanical thrombectomy, 52 via transradial access and 52 via traditional transfemoral access. They analyzed various procedural and clinical metrics between the two patient cohorts.

RESULTS

There was no difference between patient demographics or presenting symptoms of stroke severity between patients treated via transradial or transfemoral access. The mean procedural time was similar between the two treatment cohorts: 60.35 ± 36.81 minutes for the transradial group versus 65.50 ± 29.92 minutes for the transfemoral group (p = 0.451). The mean total fluoroscopy time for the procedure was similar between the two patient cohorts (20.31 ± 11.68 for radial vs 18.49 ± 11.78 minutes for femoral, p = 0.898). The majority of patients underwent thrombolysis in cerebral infarction score 2b/3 revascularization, regardless of access site (92.3% for radial vs 94.2% for femoral, p = 0.696). There was no significant difference in the incidence of access site or periprocedural complications between the transradial and transfemoral cohorts.

CONCLUSIONS

Acute stroke intervention performed via transradial access is feasible and effective, with no significant difference in procedural and clinical outcomes compared with traditional transfemoral access. Larger studies are required to further validate the efficacy and limitations of transradial access for neurointerventional procedures.

Source Image Based New 3D Rotational Angiography for Differential Diagnosis between the Infundibulum and an Internal Carotid Artery Aneurysm : Pilot Study

Objective

Distinguishing between an infundibulum and a true aneurysm is clinically important. This study aimed to evaluate whether using source image based new three-dimensional rotational angiography (S-n3DRA) can increase the rate of aneurysm detection and improve distinction between a true aneurysm and an infundibulum.

Methods

Twenty-two consecutive patients with 23 lesions, were evaluated by time-of-flight (TOF) magnetic resonance angiography (MRA), S-n3DRA, and digital subtraction angiography (DSA). The data were retrospectively and independently reviewed by two neurointerventionists, and the diagnoses based on TOF MRA, S-n3DRA, and DSA were compared. The diagnostic efficacy (interobserver agreement and diagnostic performance) of S-n3DRA was compared with that of TOF MRA.

Results

S-n3DRA showed higher interobserver agreement (κ=0.923) than TOF MRA (κ=0.465) and significantly higher accuracy than MRA in distinguishing an aneurysm from an infundibulum (p=0.0039).

Conclusion

Compared to MRA, S-n3DRA could provide better screening accuracy and information for distinguishing an aneurysm from an infundibulum. Therefore, S-n3DRA has the potential to reduce the need for DSA.

Building Three-Dimensional Intracranial Aneurysm Models from 3D-TOF MRA: a Validation Study

To create realistic three-dimensional (3D) vascular models from 3D time-of-flight magnetic resonance angiography (3D-TOF MRA) of an intracranial aneurysm (IA). Thirty-two IAs in 31 patients were printed using 3D-TOF MRA source images from polylactic acid (PLA) raw material. Two observers measured the maximum IA diameter at the longest width twice separately. A total mean of four measurements as well as each observer's individual average MRA lengths were calculated. After printing, 3D-printed anatomic models (PAM) underwent computed tomography (CT) acquisition and each observer measured them using the same algorithm as applied to MRA. Inter- and intra-observer consistency for the MRA and CT measurements were analyzed using the intraclass correlation coefficient (ICC) and a Bland-Altman plot. The mean maximum aneurysm diameter obtained from four MRA evaluations was 8.49 mm, whereas it was 8.83 mm according to the CT 3D PAM measurement. The Wilcoxon test revealed slightly larger mean CT 3D PAM diameters than the MRA measurements. The Spearman's correlation test yielded a positive correlation between MRA and CT lengths of 3D PAMs. Inter and intra-observer consistency were high in consecutive MRA and CT measurements. According to Bland-Altman analyses, the aneurysmal dimensions obtained from CT were higher for observer 1 and observer 2 (a mean of 0.32 mm and 0.35 mm, respectively) compared to the MRA measurements. CT dimensions were slightly overestimated compared to MRA measurements of the created models. We believe the discrepancy may be related to the Laplacian algorithm applied for surface smoothing and the high slice thickness selection that was used. However, ICC provided high consistency and reproducibility in our cohort. Therefore, it is technically possible to produce 3D intracranial aneurysm models from 3D-TOF MRA images.

Are Dynamic Arterial Spin-Labeling MRA and Time-Resolved Contrast-Enhanced MRA Suited for Confirmation of Obliteration following Gamma Knife Radiosurgery of Brain Arteriovenous Malformations?

BACKGROUND AND PURPOSE

Intra-arterial DSA has been traditionally used for confirmation of cure following gamma knife radiosurgery for AVMs. Our aim was to evaluate whether 4D arterial spin-labeling MRA and contrast-enhanced time-resolved MRA in combination can be an alternative to DSA for confirmation of AVM obliteration following gamma knife radiosurgery.

MATERIALS AND METHODS

In this prospective study, 30 patients undergoing DSA for confirmation of obliteration following gamma knife radiosurgery for AVMs (criterion standard) also underwent MRA, including arterial spin-labeling MRA and contrast-enhanced time-resolved MRA. One dataset was technically unsatisfactory, and the case was excluded. The DSA and MRA datasets of 29 patients were independently and blindly evaluated by 2 observers regarding the presence/absence of residual AVMs.

RESULTS

The mean time between gamma knife radiosurgery and follow-up DSA/MRA was 53 months (95% CI, 42-64 months; range, 22-168 months). MRA total scanning time was 9 minutes and 17 seconds. Residual AVMs were detected on DSA in 9 subjects (obliteration rate = 69%). All residual AVMs were detected on at least 1 MRA sequence. Arterial spin-labeling MRA and contrast-enhanced time-resolved MRA showed excellent specificity and positive predictive values individually (100%). However, their sensitivity and negative predictive values were suboptimal due to 1 false-negative with arterial spin-labeling MRA and 2 with contrast-enhanced time-resolved MRA (sensitivity = 88% and 77%, negative predictive values = 95% and 90%, respectively). Both sensitivity and negative predictive values increased to 100% if a composite assessment of both MRA sequences was performed. Diagnostic accuracy (receiver operating characteristic) and agreement (κ) are maximized using arterial spin-labeling MRA and contrast-enhanced time-resolved MRA in combination (area under receiver operating characteristic curve = 1, P < .001; κ = 1, P < .001, respectively).

CONCLUSIONS

Combining arterial spin-labeling MRA with contrast-enhanced time-resolved MRA holds promise as an alternative to DSA for confirmation of obliteration following gamma knife radiosurgery for brain AVMs, having provided 100% sensitivity and specificity in the study. Their combined use also enables reliable characterization of residual lesions.

Sinus Arrest and Bradycardia Induced by Carotid Baroreceptor Reflex Activation during Rotational Angiography: A Case Report

Objective

We describe a rare patient with a cavernous sinus dural arteriovenous fistula (CS DAVF) in whom diagnostic rotational angiography (RA) caused sinus arrest and bradycardia.

Case Presentation

A 79-year-old woman with no previous history of cardiovascular diseases presented with left oculomotor nerve paresis. Conventional angiography confirmed a bilateral CS DAVF. During a three-dimensional RA (3DRA) examination of the left internal carotid artery, sinus arrest occurred. Subsequently, the use of 3DRA to image the left external carotid artery and the use of cone beam computed tomography (CBCT) to image the left internal and external carotid artery also caused transient sinus bradycardia. Two weeks later, we inserted a temporary transvenous pacemaker and completed the transvenous embolization of the left CS DAVF. The left oculomotor paresis improved without any perioperative complications.

Conclusion

RA is a standard radiological modality for the diagnosis of cerebrovascular disease. Although the physical force generated by the injection of the contrast medium at the carotid bifurcation can theoretically cause hemodynamic instability, no previous reports have described sinus arrest or bradycardia in association with diagnostic carotid angiography. The present case demonstrates that 3DRA and CBCT can provoke rare, but serious, incidences of cardiac arrhythmia.

Cerebral angiography: Techniques and practice

As a refresher course on current techniques and practice of cerebral angiography, this chapter outlines the steps in effective angiography, incorporating modern quality and safety considerations. The format is step-by-step from preprocedure to intraprocedure to postprocedure for ease of reference. The chapter will serve as a framework for the fledgling angiographer, augmenting the important teaching provided by a seasoned angiographer.

On the Use of Digital Subtraction Angiography in Stereoelectroencephalography Surgical Planning to Prevent Collisions with Vessels

OBJECTIVE

Stereoelectroencephalography (SEEG) consists of the implantation of microelectrodes for the electrophysiological characterization of epileptogenic networks. To reduce a possible risk of intracranial bleeding by vessel rupture during the electrode implantation, the stereotactic trajectories must follow avascular corridors. The use of digital subtraction angiography (DSA) for vascular visualization during planning is controversial due to the additional risk related to this procedure. Here we evaluate the utility of this technique for planning when the neurosurgeon has it available together with gadolinium-enhanced T1-weighted magnetic resonance sequence (T1-Gd) and computed tomography angiography (CTA).

METHODS

Twenty-two implantation plans for SEEG were initially done using T1-Gd imaging (251 trajectories). DSA was only used later during the revision process. In 6 patients CTA was available at this point as well. We quantified the position of the closest vessel to the trajectory in each of the imaging modalities.

RESULTS

Two thirds of the trajectories that appeared vessel free in the T1-Gd or CTA presented vessels in their proximity, as shown by DSA. Those modifications only required small shifts of both the entry and target point, so the diagnostic aims were preserved.

CONCLUSIONS

T1-Gd and CTA, despite being the most commonly used techniques for SEEG planning, frequently fail to reveal vessels that are dangerously close to the trajectories. Higher-resolution vascular imaging techniques, such as DSA, can provide the neurosurgeon with crucial information about vascular anatomy, resulting in safer plans.

Comprehensive review of imaging of intracranial aneurysms and angiographically negative subarachnoid hemorrhage

Intracranial aneurysms confer the risk of subarachnoid hemorrhage (SAH), a potentially devastating condition, though most aneurysms will remain asymptomatic for the lifetime of the patient. Imaging is critical to all stages of patient care for those who harbor an unruptured intracranial aneurysm (UIA), including to establish the diagnosis, to determine therapeutic options, to undertake surveillance in patients who elect not to undergo treatment or whose aneurysm(s) portends such a low risk that treatment is not indicated, and to perform follow-up after treatment. Neuroimaging is equally as important in patients who suffer an SAH. DSA remains the reference standard for imaging of intracranial aneurysms due to its high spatial and temporal resolution. As noninvasive imaging technology, such as CTA and MRA, improves, the diagnostic accuracy of such tests continues to increasingly approximate that of DSA. In cases of angiographically negative SAH, imaging protocols are necessary not only for diagnosis but also to search for an initially occult vascular lesion, such as a thrombosed, ruptured aneurysm that might be detected in a delayed fashion. Given the crucial role of neuroimaging in all aspects of care for patients with UIAs and SAH, it is incumbent on those who care for these patients, including cerebrovascular neurosurgeons, interventional neurologists and neuroradiologists, and diagnostic radiologists and neurointensivists, to understand the role of imaging in this disease and how individual members of the multispecialty team use imaging to ensure best practices to deliver cutting-edge care to these often complex cases. This review expounds on the role of imaging in the management of UIAs and ruptured intracranial aneurysms and in the workup of angiographically negative subarachnoid hemorrhage.

A New Scoring System for Prediction of Underlying Vascular Pathology in Patients with Intracerebral Hemorrhage: The Modified Secondary Intracerebral Hemorrhage Score

BACKGROUND

Secondary intracerebral hemorrhage (SICH) score is used to predict risk of intracranial hemorrhage (ICH) associated vascular lesions. However, it has low clinical utility in identifying patients without need for neurovascular imaging. This study aims to develop a modified scoring system to capture patients with low risk of underlying vascular pathology, thereby decreasing need for vascular imaging and its associated morbidity.

METHODS

A retrospective analysis of 994 patients with atraumatic ICH over 8 years was conducted, excluding known underlying pathology, subarachnoid hemorrhage, or lack of vascular imaging. Using a multivariate logistic regression model, independent predictors of vascular pathology were identified and utilized toward developing a modified Secondary Intracerebral Hemorrhage (mSICH) score.

RESULTS

Of 575 patients identified, 60 (10.4%) had underlying vascular etiology. Statistically significant predictors of vascular pathology included age; female sex; admission systolic blood pressure <160 mm Hg; locations other than basal ganglia, thalamus, pons, or midbrain; presence of high-risk imaging features; and proximity to large vessel-containing cisterns. The mSICH score correlated with an increasing incidence of vascular pathology [0-1 (0%), 9 (4.3%), 12 (9.7%), 21 (40.4%), 6 (33.3%), 8 (88.9%), and 4 (100%)] and had a significantly higher number of patients receiving scores with 0% incidence of vascular lesions compared with the SICH score [159 (27.6%) versus 12 (2.1%); P < 0.001)].

CONCLUSIONS

The mSICH score can more accurately predict risk of underlying vascular pathology of ICH and identify patients with lowest risk of vascular pathology. This may minimize the cost and associated risks of invasive cerebrovascular imaging.

Access-Site Complications in Transfemoral Neuroendovascular Procedures: A Systematic Review of Incidence Rates and Management Strategies

BACKGROUND

The femoral artery is the most common access route for cerebral angiography and neurointerventional procedures. Complications of the transfemoral approach include groin hemorrhages and hematomas, retroperitoneal hematomas, pseudoaneurysms, arteriovenous fistulas, peripheral artery occlusions, femoral nerve injuries, and access-site infections. Incidence rates vary among different randomized and nonrandomized trials, and the literature lacks a comprehensive review of this subject.

OBJECTIVE

To gather data from 16 randomized clinical trials (RCT) and 17 nonrandomized cohort studies regarding femoral access-site complications for a review paper. We also briefly discuss management strategies for these complications based on the most recent literature.

METHODS

A PubMed indexed search for all neuroendovascular clinical trials, retrospective studies, and prospective studies that reported femoral artery access-site complications in neurointerventional procedures.

RESULTS

The overall access-site complication rate in RCTs is 5.13%, while in in non-RCTs, the rate is 2.78%. The most common complication in both groups is groin hematoma followed by access-site hemorrhage and femoral pseudoaneurysm. On the other hand, wound infection was the least common complication.

CONCLUSION

The transfemoral approach in neuroendovascular procedures holds risk for several complications. This review will allow further studies to compare access-site complications between the transfemoral approach and other alternative access sites, mainly the transradial approach, which is gaining a lot of interest nowadays.

Evaluation of the angiographic outcomes after clipping of intracranial aneurysms: determination of predisposing factors for occurrence of aneurysm remnants

Objectives: Aneurysm remnants after microsurgical clipping have a risk of regrowth and rupture and have not been validated in the era of three-dimensional angiography. Therefore, this study aimed to evaluate the angiographic outcome using three-dimensional rotational images and determine the predictors for remnants after microsurgical clipping.Methods: Between January 2014 and May 2017, 139 aneurysms in 106 patients who were treated with microsurgical clipping, were eligible for this study. For the determination of aneurysm remnants after microsurgical clipping, the angiographic outcomes were evaluated using follow-up digital subtraction angiography within 7 days for unruptured aneurysms or within 2 weeks for ruptured aneurysms. According to the Sindou classification, the aneurysm remnants were dichotomized, and subgroup analysis was performed to identify the predictors of aneurysm remnants after clipping with various imaging parameters and clinical information.Results: The overall rate of aneurysm remnants was 29.5% (41/139), in which retreatments were needed in 6.5% (9/139). The neck size and maximum diameter of aneurysms were independent predisposing factors for the aneurysm remnants that need retreatment (OR: 2.30; p < 0.001; OR: 1.38; p < 0.001, respectively).Conclusions: This study demonstrated a low incidence of aneurysm remnants after microsurgical clipping which need to retreatment. However, selective postoperative angiography could provide us clear information of surgical result and evidence for long-term follow-up for some aneurysms with larger neck size (>5.7 mm) and maximum diameter (>7.1 mm).

Cervical Spine Fractures: Who Really Needs CT Angiography?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Compare a novel two-step algorithm for indicating a computed tomography angiography (CTA) in the setting of a cervical spine fracture with established gold standard criteria.

SUMMARY OF BACKGROUND DATA

As CTA permits the rapid detection of blunt cerebrovascular injuries (BCVI), screening criteria for its use have broadened. However, more recent work warns of the potential for the overdiagnosis of BCVI, which must be considered with the adoption of broad criteria.

METHODS

A novel two-step metric for indicating CTA screening was compared with the American College of Surgeons guidelines and the expanded Denver Criteria using patients who presented with cervical spine fractures to a tertiary-level 1 trauma center from January 1, 2012 to January 1, 2016. The ability for each metric to identify BCVI and posterior circulation strokes that occurred during this period was assessed.

RESULTS

A total of 721 patients with cervical fractures were included, of whom 417 underwent CTAs (57.8%). Sixty-eight BCVIs and seven strokes were diagnosed in this cohort. All algorithms detected an equivalent number of BCVIs (52 with the novel metric, 54 with the ACS and Denver Criteria, P = 0.84) and strokes (7/7, 100% with the novel metric, 6/7, 85.7% with the ACS and Denver Criteria, P = 1.0). However, 63% fewer scans would have been needed with the proposed screening algorithm compared with the ACS or Denver Criteria (261/721, 36.2% of all patients with our criteria vs. 413/721, 57.3% with the ACS standard and 417/721, 57.8%) with the Denver Criteria, P < 0.0002 for each).

CONCLUSION

A two-step criterion based on mechanism of injury and patient factors is a potentially useful guide for identifying patients at risk of BCVI and stroke after cervical spine fractures. Further prospective analyses are required prior to widespread clinical adoption.

LEVEL OF EVIDENCE

4.

Transradial approach for acute stroke intervention: technical procedure and clinical outcomes

Background and purpose

Radial artery catheterisation is an alternate route of access that has recently started to gain more widespread use for neuroendovascular procedures, including acute stroke intervention. In this small case series, we present our institution’s outcomes in patients undergoing acute stroke interventions via transradial access.

Materials and methods

We present a retrospective study of 15 patients who underwent acute stroke intervention via radial artery access. We analyse these patients’ periprocedural and clinical outcomes after undergoing mechanical thrombectomy.

Results

A total of 15 consecutive patients were included in the study (9 males and 6 females), and all patients were able to successfully undergo mechanical thrombectomy via radial artery access. The mean time of arterial puncture to reperfusion was 50±28 min (range: 15–104). A TICI 2b/3 revascularisation was achieved in 13/15 patients (87%); a TICI 1 and TICI 2a outcome was achieved on the other two patients. One patient incurred an iatrogenic vessel dissection during the procedure. Eight of out 15 patients (53%) had favourable mRS (0–3) at the time of discharge from the hospital.

Conclusion

Radial artery catheterisation is technically feasible for performing acute stroke interventions with favourable time to revascularisation and good overall clinical outcomes.

Rabbit Model of Intra-Arterial Chemotherapy Toxicity Demonstrates Retinopathy and Vasculopathy Related to Drug and Dose, Not Procedure or Approach

Purpose

To use our intra-arterial chemotherapy (IAC) rabbit model to assess the impact of IAC procedure, drug, dose, and choice of technique on ocular structure and function, to study the nature and etiology of IAC toxicity, and to compare to observations in patients.

Methods

Rabbits received IAC melphalan (0.4-0.8 mg/kg), carboplatin (25–50 mg), or saline, either by direct ophthalmic artery cannulation, or with a technique emulating nonocclusion. Ocular structure/function were assessed with examination, electroretinography (ERG), fundus photography, fluorescein angiography, optical coherence tomography (OCT), and OCT angiography, prior to and 5 to 6 weeks after IAC. Blood counts were obtained weekly. We reviewed our last 50 IAC treatments in patients for evidence of ocular or systemic complications.

Results

No toxicity was seen in the saline control group. With standard (0.4 mg/kg) melphalan, no vascular/microvascular abnormalities were seen with either technique. However, severe microvascular pruning and arteriolar occlusions were seen occasionally at 0.8 mg/kg doses. ERG reductions were dose-dependent. Histology showed melphalan dose-dependent degeneration in all retinal layers, restricted geographically to areas of greatest vascular density. Carboplatin caused massive edema of ocular/periocular structures. IAC patients experienced occasional periocular swelling/rash, and only rarely experienced retinopathy or vascular events/hemorrhage in eyes treated multiple times with triple (melphalan/carboplatin/topotecan) therapy. Transient neutropenia occurred after 46% of IAC procedures, generally after triple therapy.

Conclusions

IAC toxicity appears to be related to the specific drug being used and is dose-dependent, rather than related to the IAC procedure itself or the specific technique selected. These rabbit findings are corroborated by our clinical findings in patients.

Frameless Stereotactic Navigation during Insular Glioma Resection using Fusion of Three-Dimensional Rotational Angiography and Magnetic Resonance Imaging

BACKGROUND

Perioperative cerebral infarction is a potential complication of glioma resection, of which insular tumors are at higher risk because of the proximity of middle cerebral artery branches, including the lateral lenticulostriates and long insular arteries. In this study, 3 patients received three-dimensional rotational angiography, which was fused with magnetic resonance imaging (MRI) for frameless stereotactic navigation during dominant-hemisphere insular glioma resection.

METHODS

All patients obtained a preoperative catheter angiogram with a three-dimensional rotational acquisition of the ipsilateral internal carotid artery. The pixel-based axial three-dimensional angiography data, thin-cut structural MRI, tractography from diffusion tensor imaging, and expressive language activation from functional MRI were uploaded into the iPlan software (Brainlab, Heimstetten, Germany) and fused. The target tumor, regional blood vessels, adjacent functional areas, and their associated fiber tracts were segmented and overlaid on the appropriate MRI sequence. This image fusion was used preoperatively to visualize the relationship of the mass with the adjacent vasculature and intraoperatively for frameless stereotactic navigation to optimize preservation of arterial structures.

RESULTS

Three patients aged 27-60 years with excellent baseline functional status presented with seizures and were found to have a large dominant-hemisphere T2 hyperintense nonenhancing insular mass. Surgical resection was performed using multimodality neuronavigation. None sustained a postoperative arterial infarction or a perioperative neurologic deficit.

CONCLUSIONS

Neuronavigation using a fusion of three-dimensional rotational angiography with MRI is a technique that can be used for preoperative planning and during resection of insular gliomas to optimize preservation of adjacent arteries.