Transradial versus transfemoral access routes for diagnostic cerebral angiography: a large single-center comparative cost-analysis study

OBJECTIVE

Recently, the transradial (TR) approach has become a common alternative because of its safety profile and increased patient satisfaction compared with the transfemoral (TF) route. Both routes are associated with their respective associated costs, and differences typically emerge on the basis of patient anatomy, operator expertise, and occurrence of complications. The authors' objective was to compare the overall costs of diagnostic cerebral angiography via both routes and to shed light on the individual equipment costs of each route.

METHODS

This retrospective single-center study of 926 elective diagnostic angiograms was performed between December 2019 and March 2022.

RESULTS

The study comprised of 314 and 612 angiograms performed through the TF and TR routes, respectively. A significantly greater proportion of female patients were included in the TF cohort (79.3% vs 67.8%, p < 0.001), and most other demographic characteristics and baseline modified Rankin Scale scores were comparable between cohorts. The overall cost of patients utilizing the TR route was comparable to that of the TF route (mean ± SD $12,591.80 ± $19,128.00 vs $12,789.50 ± 18,424.00, p = 0.88). However, the median cost of catheters was significantly higher in TR group ($55.20 vs $12.40, p = 0.03), while the median costs of closure devices ($87.00 vs $20.20 p < 0.001) and sheaths ($44.60 ± 11.3 vs $41.10 ± 3.10, p < 0.001) were significantly higher in the TF group.

CONCLUSIONS

Overall, the authors' study showed that the TR approach can be a less expensive option for patients undergoing diagnostic cerebral angiography, especially if complications occur. Future studies may corroborate these findings and potentially lead to the adoption of TR as a low-cost, efficient, gold-standard technique for cerebral angiography.

ARISE I Consensus Review on the Management of Intracranial Aneurysms

BACKGROUND

Intracranial aneurysms (IAs) remain a challenging neurological diagnosis associated with significant morbidity and mortality. There is a plethora of microsurgical and endovascular techniques for the treatment of both ruptured and unruptured aneurysms. There is no definitive consensus as to the best treatment option for this cerebrovascular pathology. The Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts discussed best practices and the most promising approaches to improve the management of brain aneurysms.

METHODS

A group of experts from academia, industry, and federal regulators convened to discuss updated clinical trials, scientific research on preclinical system models, management options, screening and monitoring, and promising novel device technologies, aiming to improve the outcomes of patients with IA.

RESULTS

Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts suggested the incorporation of artificial intelligence to capture sequential aneurysm growth, identify predictors of rupture, and predict the risk of rupture to guide treatment options. The consensus strongly recommended nationwide systemic data collection of unruptured IA radiographic images for the analysis and development of machine learning algorithms for rupture risk. The consensus supported centers of excellence for preclinical multicenter trials in areas such as genetics, cellular composition, and radiogenomics. Optical coherence tomography and magnetic resonance imaging contrast-enhanced 3T vessel wall imaging are promising technologies; however, more data are needed to define their role in IA management. Ruptured aneurysms are best managed at large volume centers, which should include comprehensive patient management with expertise in microsurgery, endovascular surgery, neurology, and neurocritical care.

CONCLUSIONS

Clinical and preclinical studies and scientific research on IA should engage high-volume centers and be conducted in multicenter collaborative efforts. The future of IA diagnosis and monitoring could be enhanced by the incorporation of artificial intelligence and national radiographic and biologic registries. A collaborative effort between academic centers, government regulators, and the device industry is paramount for the adequate management of IA and the advancement of the field.

Incidence and Outcomes of Posterior Circulation Involvement in Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a progressive, occlusive disease of the internal carotid arteries and their proximal branches, with the subsequent development of an abnormal vascular network that is rupture-prone. Steno-occlusive changes in the posterior cerebral arteries (PCAs) may contribute to worsened outcomes in patients with MMD; however, there is little information on the incidence and natural history of posterior circulation MMD (PCMMD). We describe clinical PCMMD characteristics in a large cohort of patients with MMD.

METHODS

We retrospectively reviewed patients with MMD treated between 1991 and 2019 at a large academic medical center. Demographics, perioperative outcomes, and radiological phenotypes were recorded for 770 patients. PCA disease was graded as either 0 (no disease), 1 (mild), 2 (moderate), or 3 (severe or occluded) based on cerebral angiography. Patients with angiographically confirmed MMD diagnosis with at least 6 months follow-up and completion of revascularization surgery were included; patients with intracranial atherosclerosis, intracranial dissection, vasculitis, and undefined inflammatory processes were excluded. The presence of stenosis/occlusion was graded radiographically to assess for disease progression and the prevalence of risk factors related to reduced progression-free survival.

RESULTS

In all, 686 patients met the inclusion criteria, with PCA disease identified in 282 (41.1%) patients. Of those 282 patients with PCMMD, disease severity ranged from 99 (35.1%) with mild, 72 (25.5%) with moderate, and 111 (39.4%) with severe. The total number of postoperative complications was significantly associated with PCMMD severity (P=0.0067). Additionally, PCMMD severity correlated with worse postoperative modified Rankin Scale scores (P<0.0001). At a mean follow-up of 6.0±3.9 (range, 0.1-25.0) years, a total of 60 (12.6%) patients showed new/worsening PCMMD. The overall postoperative, progression-free survival in patients with PCMMD was 95.4% at 1 year, 82.4% at 3 years, 68.8% at 5 years, and 28.3% at 10 years, with prognostic factors for progression including preoperative PCMMD status, history of tobacco use, and hypertension (P<0.0001, P<0.001, and P<0.0001, respectively).

CONCLUSIONS

PCA disease involvement in MMD is associated with higher rates of ischemic perioperative complications and worsened functional outcomes, likely due to reduced collateral flow. Ten-year progression of PCA disease is highly likely and should be monitored throughout follow-up; future studies will assess the impact of PCA disease progression on long-term outcomes.

Angiographic and clinical outcomes from 396 aneurysms treated with the pipeline flex embolization device with shield technology

BACKGROUND

The PEDESTRIAN registry demonstrated high rates of complete long-term occlusion and good clinical outcomes among patients with intracranial aneurysms treated with the pipeline embolization device. The pipeline flex embolization device with shield technology was introduced to minimize thromboembolic complications. In this study, we investigated the safety and effectiveness of pipeline embolization device with shield technology among all patients treated for intracranial aneurysms at our center.

METHODS

This was a single-arm retrospective study of prospectively collected data of patients treated with pipeline embolization device with shield technology at our high-volume center between January 2018-January 2021. The primary efficacy endpoint was complete occlusion as measured by a class 1 Raymond-Roy score at 1-year and 2-year follow-up. The primary safety endpoint was major morbidity and neurological mortality up to 1 year following intervention.

RESULTS

A total of 328 patients (mean age 56.1 ± 14.7 years; 81.1% female), 80 of whom were previously included in PEDESTRIAN, with 396 aneurysms, were analyzed. A total of 378 devices were deployed, with 93.9% (372/396) of aneurysms requiring only one device. Follow-up angiography was available for 90.2% (296/328) of the procedures after a mean time of 14.0 ± 8.2 months. Complete occlusion was demonstrated for 78.5% (132/168) of aneurysms at 12 months and 90.7% (98/108) at 24 months. The overall rates of major morbidity and neurological mortality after 2 years were 1.5% (5/328) and 0.6% (2/328), respectively.

CONCLUSION

Our results demonstrate high rates of complete long-term occlusion among patients treated with pipeline embolization device with shield technology. We also observed low rates of mortality and morbidity consistent with fewer thromboembolic complications with pipeline embolization devices with shield technology.

[Radiation Dose Reduction through the Optimization of Mask Images in Cerebral Angiography]

PURPOSE

To verify the effectiveness of optimizing the number of mask images in DSA for radiation dose reduction during cerebral angiography.

METHODS

A total of 60 angiography sessions in 2 times for 30 patients performed by the same operator were included in this study. In order to compare the effects of optimization to change the injection delay time of DSA from 1 s to the shortest possible time, the number of mask images, the number of imaging frames, and radiation doses between sessions were compared and analyzed retrospectively.

RESULTS

In one DSA run, the number of mask images was decreased from 6 (5-7) to 3 (2-3) frames (p<0.01)/57.1% (median [IQR]/reduction rate), the number of imaging frames was decreased from 34 (32-36) to 32 (29-34) frames (p<0.01)/7.9%, and the radiation dose was decreased from 33 (23-47) to 30 (21-40) mGy (p<0.01)/8.3%. In magnification angiography, the reductions rate was significantly increased. In one angiography session, the number of mask images was decreased from 45 (35-72) to 19 (16-34) frames (p<0.01)/54.6%, the number of imaging frames was decreased from 242 (199-385) to 211 (181-346) frames (p<0.01)/8.3%, the radiation dose of DSA was decreased from 295 (190-341) to 242 (167-305) mGy (p<0.01)/11.6%, and the total radiation dose was decreased from 369 (259-418) to 328 (248-394) mGy (p<0.01)/7.5%.

CONCLUSION

Using the shortest possible injection delay time for the number of mask image optimization was an effective radiation dose reduction method.

Case Report: A Rare Case of Iodixanol-Induced Anaphylactic Shock in Cerebral Angiography

Background

Adverse reactions induced by isoosmolar contrast medium (iodixanol) are mostly mild, with rashes and headaches being the most common. Although anaphylactic shock has been reported, no related incidents have been documented on cerebral angiography.

Objective

This article reports a serious case of anaphylactic shock possibly induced by iodixanol and provides an overview of the case report.

Case Summary

A 65-year-old female with persistent headaches for nearly six months and CTA examination revealed multiple intracranial aneurysms. After two treatments, she returned to the hospital for aneurysm of reexamination a month ago. Following a preoperative assessment, cerebral angiography was performed. Three minutes after the procedure, the patient experienced dizziness, increased heart rate, followed by hypotension (BP 90/43 mm Hg), a sudden drop-in heart rate (HR 68 bpm), and a drop in SpO2 to 92%. Intravenous dexamethasone for anti-allergic were administered immediately, along with therapy through oxygen-inhalation. However, the patient then developed limb convulsions, unresponsiveness, and was urgently given diazepam for sedation and sputum aspiration to maintain airway patency. Blood pressure decrease to 53/29 mm Hg, and SpO2 readings were unavailable. Intravenous dopamine to elevates blood pressure, and assists breathing by intubating in the endotracheal. After 3 minutes, as the blood pressure remained undetectable, intermittent intravenous epinephrine 1mg was administered to raise the blood pressure, gradually restoring it to 126/90 mm Hg, and SpO2 increased to 95%. The patient was diagnosed with iodixanol-induced anaphylactic shock and urgently transferred to the NICU for monitoring and treatment. The patient died despite immediate treatment.

Conclusion

A 65-year-old female developed serious anaphylactic shock during cerebral angiography after receiving iodixanol. Although iodixanol is considered one of the safest iodinated contrast mediums (ICM), clinicians should be aware of its the potential for serious hypersensitivity reactions that can lead to fatal and life-threatening events.

Distal radial artery approach is safe and effective for cerebral angiography and neuroendovascular treatment: A single-center experience with ultrasonographic measurement

BACKGROUND

The transradial artery approach to cerebral angiography can reduce both patient stress following examination and the risk of major complications due to hematoma. Recently, the distal radial artery approach (DRA) has garnered attention in cardiology as a minimally invasive method. DRA is also considered applicable to neurosurgery, although concerns about procedural difficulty and complications persist. Therefore, this study aimed to evaluate the efficacy of the DRA in cerebral angiography and neuroendovascular treatment.

METHODS

We retrospectively selected 30 consecutive patients for whom the DRA was attempted for cerebral angiography at our hospital. The patients' age, sex, height, weight, and medical history information was collected and correlated with successful puncture and complications. The diameter of the distal radial artery (RA) was measured using ultrasonography.

RESULTS

The median patient age was 67 years (range, 32-87 years) and 21 (70%) were men. The median diameter of the distal RA was 2.3 mm (range, 1.7-3.2 mm). Distal RA puncture was successful in 23 patients (77%) and no complications were noted; however there was no significant correlation between successful puncture and any of the patient factors. Carotid artery stenting and preoperative tumor embolization were performed via DRA in six and three cases, respectively. Although puncture site hematoma occurred in only one case, all treatments were successful, and no major complications were observed.

CONCLUSION

DRA can be safely used for cerebral angiography and neuroendovascular treatment.

Paediatric Moyamoya disease: acute presentation with fever and confusion in an 8-year-old: a case report

Introduction and importance

Moyamoya is a chronic vaso-occlusive cerebrovascular disorder which involves internal carotid artery and its proximal branches, forming compensatory Moyamoya vessels. It may manifest with diverse symptoms, but early detection is crucial for a favourable prognosis.

Case presentation

The authors present a case of an 8-year-old child who presented to the emergency with acute onset fever and confusion in speech. Although the symptoms were vague, she was advised for a thorough investigation. MRI of the brain revealed an infarct on the brain that raised suspicion of a vaso-occlussive disorder. Subsequent magnetic resonance angiography and digital subtraction angiography revealed underlying Moyamoya disease.

Clinical discussion

Although the initial diagnosis of Moyamoya disease can be challenging, prompt diagnosis and simple medical measures like single antiplatelet regimens are useful for secondary ischaemic prevention.

Conclusion

This case highlights the essence of considering Moyamoya disease as one of the differentials while dealing with children presenting with subtle cerebrovascular symptoms.

Moyamoya Disease with Non-Functional Pituitary Macroadenoma: A Case Report of a Rare Presentation

Moyamoya disease (MMD) is a rare neurological condition characterized by brain blood vessel narrowing, leading to collateral vessel formation. Diagnosis typically involves cerebral angiography and magnetic resonance angiography (MRA), with surgical revascularization often providing superior outcomes. Here, we present the case of a 55-year-old woman with hypertension, diabetes, and a history of ischemic stroke. She recently experienced a hemorrhagic stroke due to MMD, compounded by a non-functional pituitary macroadenoma. Recognizing signs of a hemorrhagic stroke is crucial to prevent future occurrences and ensure optimal outcomes. However, our understanding of the connection between MMD and pituitary macroadenoma remains incomplete. Further research is essential to refine diagnostic techniques and treatment strategies. Through continued research and awareness, we can strive for improved outcomes and an enhanced quality of life for individuals affected by MMD and its complications.

Detection of moderate to severe middle cerebral artery atherosclerotic stenosis in stroke patients: Transcranial color-coded duplex sonography versus computed tomography angiography

Background

Intracranial atherosclerotic stenosis is a common cause of ischemic cerebrovascular events and is associated with a high risk of stroke recurrence. This study aimed to assess the diagnostic accuracy of transcranial color-coded duplex sonography for moderate-to-severe middle cerebral artery stenosis in stroke patients.

Methods

A retrospective analysis was carried out, including 31 patients aged ⩾18 years hospitalized for ischemic cerebrovascular event in whom middle cerebral artery stenosis ⩾30% was identified on computed tomography angiography. Transcranial color-coded duplex sonography findings were compared to the degree of stenosis blindly identified on the computed tomography angiography used as the reference method.

Results

Overall, 27 patients had M1 stenosis and the other 4 had M2 stenosis. To detect M2 stenosis ⩾ 50% and ⩾ 70%, stenotic to pre-stenotic ratio ⩾ 2 and ⩾ 3 had a sensitivity of 100%, respectively. To detect M1 stenosis ⩾ 70%, peak systolic velocity ⩾ 300 cm/s had a sensitivity of 53.8% and specificity of 85.7% with area under the receiver-operating characteristic curve of 0.753 (95% confidence interval: 0.568-0.938; p = 0.026), and stenotic to pre-stenotic ratio ⩾ 3 had a sensitivity of 84.6% and a specificity of 78.6% (area under the curve = 0.854; 95% confidence interval: 0.707-1; p = 0.002). Middle cerebral artery/anterior cerebral artery velocity ratio < 0.7 had a sensitivity of 57.1% and specificity of 90% to detect dampened pre-stenotic flow in middle cerebral artery secondary to downstream M1 stenosis ⩾ 70% (area under the curve = 0.800; 95% confidence interval: 0.584-1; p = 0.040).

Conclusion

This study showed that stenotic to pre-stenotic ratio ⩾ 3 was more sensitive than peak systolic velocity ⩾ 300 cm/s to screen M1 stenosis ⩾ 70%. Middle cerebral artery/anterior cerebral artery ratio < 0.7 was a good indirect sign to detect dampened pre-stenotic flow due to M1 stenosis ⩾ 70%.

Diagnostic Pitfalls of Macrocephaly and Intracranial Dural Arteriovenous Fistulas: Connecting the Dots With the Red Flags

Macrocephaly is defined as an abnormal increase in head circumference greater than two standard deviations above the mean for a given age and sex. We present the case of a 16-month-old boy with congenital progressive macrocephaly, who was referred to our hospital for a ventriculoperitoneal shunt placement for external hydrocephalus diagnosed at 13 months of age. The patient had a febrile seizure 12 hours after the shunt was placed and the emergency CT exam revealed collapsed ventricles and a right frontal subdural collection, suggestive of an over-drainage and intracranial hypotension. A subsequent electroencephalogram (EEG) revealed some anomalies, but the patient was discharged two days later due to having no neurological symptoms after being placed on anticonvulsants. The patient returned to the hospital one week later due to recurrent seizures. Further clinical examination revealed prominent and tortuous veins of the skull, palpated in the left occipital region. A thrill and a left carotid murmur were heard during auscultation. A subsequent brain MRI with MR arteriography and venography was performed in search of an explanation for hydrocephaly. The sequences were suggestive of a dural arteriovenous fistula, which was confirmed and then treated using coils during an interventional angiography. A second procedure was performed two months later to complete the embolization, with subsequent imaging follow-ups showing the procedure to have been successful. The measurement of the cranial circumference, its regular evaluation, and its evolution allow a hierarchical diagnosis strategy by distinguishing primary and secondary macrocephaly, progressive or not. Dural arteriovenous fistulas (DAVF) are an under-appreciated cause of macrocephaly, with which they are associated in 35% of cases. Intracranial DAVFs are pathologic shunts between dural arteries and dural venous sinuses, meningeal veins, or cortical veins. Patients with DAVFs may be completely asymptomatic. Symptoms, when present, may range from neurological deficits, seizures, and hydrocephaly to fatal hemorrhage. The symptoms depend on the location and venous and drainage patterns of the DAVF. They can be difficult to identify on routine MRIs unless specifically searched for, especially in cases of technically suboptimal examinations. We aim to give a practical approach to identify the clinical clues that warrant further investigation. Several specific protocols exist regarding the management of macrocephaly and should be followed carefully once a diagnosis has been reached, but further studies are needed to integrate more clinical and neuroimaging findings to permit an early diagnosis.

Traumatic Aneurysm Involving the Posterior Communicating Artery

Traumatic intracranial aneurysms (TICAs) are rare, accounting for less than 1% of all intracranial aneurysms. However, they are associated with a mortality rate of over 50%. The case presented herein focuses on a posterior communicating artery TICA caused by violent aggression. A 41-year-old man with massive subarachnoid hemorrhage (SAH), on admission to hospital, had a CT angiography that showed a ruptured left posterior communicating artery aneurysm with continuous blood loss and underwent neurosurgical cooling. The CT scan also showed fractures of the mandible, mastoid and left styloid process, as well as brain contusions caused by blows and kicks. Despite medical treatment and surgery, after four days, he died. The assault dynamics were recorded by a camera in the bar. The damage was caused by kicks to the neck and head. The forensic neuropathological examination showed the primary injury (SAH, subdural hemorrhage, cerebral contusions, head-neck fractures), as well as secondary damage following the attack (cerebral infarcts, edema, supratentorial hernia, midbrain hemorrhage). The coil was intact and well positioned. In this case, circumstantial information, medical records, and the type of injury could shed light on the mechanism of the production of a TICA. In addition, the CT angiography and histological investigations helped to distinguish a recent and traumatic aneurysm from a pre-existing one. Following precise steps, the study of aneurysms can be helpful in clarifying their traumatic origin even when the victim was taking drugs. The aim of this study is also to share the diagnostic process that we used in the forensic field for the assessment of suspected traumatic aneurysms.

The safety and feasibility of using a 5-Fr guiding catheter with a 0.035-inch guidewire in place for cerebral angiography

BACKGROUND

This study aimed to evaluate the safety and efficacy of performing diagnostic cerebral angiography using a 5-Fr guiding catheter with a 0.035-inch guidewire in place.

METHODS

Actual flow rates at different pressures using the 5-Fr guiding catheter with a 0.035-inch guidewire in place were measured in vitro. Integrity of the guidewire surface after high-pressure injection was determined by examination under a light microscope and scanning electron microscope. Injected and unused contrast medium were collected and analyzed using a particle detector. Furthermore, a prospective randomized controlled study was conducted to compare safety and efficacy between the guided (guidewire in place) and conventional methods.

RESULTS

The maximum injection pressure at a flow rate of 5 mL/s for the various types of commonly used contrast medium was approximately 350 psi, which is below the pressure limit for cerebral angiography. The guidewire surface remained relatively intact after multiple high-pressure injections. Procedure success and primary success rates did not significantly differ between the guided and conventional methods. However, procedure time (25.93 ± 4.07 vs 31.55 ± 5.49 minutes) and radiation exposure time (12.16 ± 3.82 vs 17.27 ± 6.12 minutes) were significantly shorter in the guided method group.

CONCLUSION

The guided catheterization method is safe and feasible for cerebral angiography and has several advantages over the conventional method.

Association between diabetes mellitus and postoperative urinary retention after cerebral angiography

AIMS

The aim of this study is to examine the association between diabetes mellitus and postoperative urinary retention on cerebral angiography (including intravascular interventional therapy).

METHODS

We collected data on the demographic characteristics and comorbidities, imaging and routine laboratory data, surgical information, and medications of patients who underwent cerebral angiography. Multivariate logistic regression was used to explore the correlation between diabetes and the incidence of postoperative urinary retention.

RESULTS

A total of 932 patients were included, with a mean age of 59.7 years (74.1% men). Postoperative urinary retention occurred in 40.8% of the diabetes mellitus group and 30.3% of the group without diabetes. Compared with the group without diabetes, those with diabetes were more likely to experience postoperative urinary retention. Patients with higher glycosylated hemoglobin A1c levels had a higher risk of developing postoperative urinary retention.

CONCLUSIONS

Diabetes was independently linked to postoperative urinary retention following cerebral angiography and patients with glycosylated hemoglobin A1c levels > 6% were more likely to experience postoperative urinary retention. Therefore, clinically regulating blood glucose levels may help to reduce the likelihood of postoperative urinary retention after cerebral angiography.

Contrast-medium injury of spinal cord after cerebral angiography using nonionic contrast agents: A case report and literature review

INTRODUCTION

Contrast-induced spinal cord injury (CIS) is an uncommon yet severe neurological complication following cerebral angiography. It can lead to dire consequences, including limb paralysis, respiratory distress, and even death.

PATIENT CONCERNS

After undergoing cerebral angiography, a 41-year-old male initially displayed symptoms of dizziness and blurred vision, which advanced into dysphoria and limb weakness within 3 hours. These initial symptoms diminished by the 12th hour. Yet, 18 hours following the procedure, the patient developed quadriplegia and paresthesia below the T5 level, even though his deep sensory functions persisted unaffected.

DIAGNOSIS

The magnetic resonance imaging and diffusion weighted imaging scans excluded the presence of cerebrovascular ischemia or subarachnoid hemorrhage. However, the magnetic resonance angiography displayed arterial vasospasms in both posterior cerebral arteries and the V4 segment of the right vertebral artery. The encephalopathy symptoms faded within 12 hours, suggesting a probable contrast-induced encephalopathy diagnosis. An magnetic resonance imaging on day 4 revealed an intensified signal in the spinal cord from C1 to T1. This finding supported the diagnosis of CIS.

INTERVENTIONS

Following treatment with mannitol, methylprednisolone, and nimodipine, the patient's contrast-induced encephalopathy symptoms resolved completely within 12 hours. With a 2-week regimen of aspirin, methylprednisolone, and rehabilitative training, the neurological symptoms from CIS showed steady improvement.

OUTCOMES

The symptoms and signs of CIS gradually improved after 2 weeks' treatment and rehabilitation program.

CONCLUSION

Given the grave outcomes of CIS, like limb paralysis, breathing difficulties, and even fatality, it is imperative to remain cautious about this complication, even with the use of modern, less harmful contrast agents.

Contrast-Induced Encephalopathy after Endovascular Treatment: Two Case Reports

Contrast-induced encephalopathy (CIE) is a rare neurological complication that occurs after the use of contrast medium in various angiographic procedures. Symptoms can be different, from headache to severe neurological deficit and coma. In the articles published to date, symptoms appeared immediately after application of contrast agent or within 24 hours. Here we present two cases of patients in whom CIE developed delayed after endovascular treatment.

Transradial and transfemoral accesses for cerebral angiography: a retrospective comparative study

OBJECTIVE

Many large randomized trials in interventional cardiology have shown a significant advantage of transradial access (TRA) over transfemoral access (TFA). However, TRA has yet been widely used in Neurovascular interventional surgery. The purpose of this retrospective comparative study is to compare the effectiveness and safety of transradial and transfemoral accesses for cerebral angiography.

METHODS

A total of 380 patients underwent cerebral angiography in our center between January 2019 and January 2021. Among them, 192 patients underwent TRA, and 188 patients via TFA. The success rate of cerebral angiography, X-ray time, total absorbed dose, dose-area product (DAP), complications, and other clinical data were extracted.

RESULTS

The operative success (94.27% vs 97.87%; P = 0.071) and the puncture failure (1.56% vs 1.60%) were not significantly different between the TRA and TFA groups. Only arterial spasm, which is more common in the TRA group, was substantially different between the two groups in terms of surgical consequences (P = 0.015). In addition, there were no significant differences between the groups in total absorbed dose (P = 0.604) and DAP(P = 0.097). However, the X-ray time of the TRA group [281.50(216.30,342.00)] was shorter than the TFA group [296.50(230.80,363.50)] (P = 0.019).

CONCLUSIONS

TRA is effective and safe in cerebral angiography, and its use may be expanded.

Utilisation of the Scepter Mini dual-lumen balloon - An illustrative series

BACKGROUND

Dual-lumen balloon microcatheters can aid in the safety and efficacy of endovascular embolisation of cerebrospinal vascular malformations. The Scepter Mini dual-lumen balloon is a novel device with a smaller profile than previous balloon microcatheters, opening up new indications not only in the treatment of cerebrospinal malformations but in various other neurovascular therapeutic and diagnostic scenarios.

METHODS

Following institutional ethics review board approval, a retrospective review of our prospectively maintained database of cases employing the Scepter Mini dual-lumen microballoon catheter was conducted. Five cases in particular were highlighted, demonstrating utilisation of this device, which may be of interest to the Neurointerventionalist. Patient demographics, procedure details, complications and clinical outcome data were reviewed.

RESULTS

Five cases employing the Scepter Mini dual-lumen microballoon catheter are presented; trans-arterial embolisation of cerebral AVM, pre-operative tumour embolisation, diagnostic angiography, trans-venous embolisation of cerebral AVM and trans-arterial embolisation of DAVF. No intraprocedural complications were recorded, one patient had a delayed haemorrhage.

CONCLUSION

Potential utilisation of the Scepter Mini lies not only in the trans-arterial embolisation of cerebrospinal vascular malformations, but in a range of other diagnostic and therapeutic indications as demonstrated.

Diagnostic Yield of Bone Window Computed Tomography and Cerebral Angiography Testing Congenital Bilateral Hypoplasia of the Internal Carotid Artery

We herein report a case of congenital bilateral hypoplasia of the internal carotid artery (ICA) that was diagnosed by bone window computed tomography (CT) and cerebral angiography. A 23-year-old woman presented with left dominant quadriplegia. Brain magnetic resonance imaging showed not only massive infarcts in the anterior circulation but also poor depiction of the bilateral ICAs. Bilateral carotid canals on bone window CT suggested hypoplasia. Cerebral angiography revealed narrowing of each ICA above its bifurcation, and the blood supply to the intercranial carotid systems developed from the vertebrobasilar system through the posterior communicating arteries and posterior cerebral arteries. We diagnosed the patient with congenital bilateral hypoplasia of the ICA based on bone CT and cerebral angiography findings. Performing both bone window CT and cerebral angiography can facilitate the diagnosis of congenital hypoplasia of the ICA.

Transradial versus transfemoral approach in cerebral angiography: A meta-analysis

BACKGROUND

Cerebral angiography has two common access sites: Transradial approach and transfemoral approach. However, there's no definitive answer to which one is superior.

OBJECTIVE

Compare transradial approach and transfemoral approach for a cerebral angiography procedure.

METHODS

A systematic review of the literature of studies reporting both transradial approach and transfemoral approach results was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. PubMed, Cochrane Library, and Embase were queried.

RESULTS

The meta-analysis examined 18 studies comprising 9388 patients undergoing cerebral angiography. Among the patients, 4598 underwent transradial approach (48.9%) and 4790 underwent transfemoral approach (51.1%). Our results revealed no statistical differences between the approaches regarding procedure success, crossover to transfemoral approach, procedure and fluoroscopy time between both approaches in cerebral angiography. Total, major, and minor complications comparisons were more favorable to transradial approach for this procedure.

CONCLUSION

These findings suggest, despite the ultimate decision regarding the choice of access method might be influenced by the physician's experience and personal preference, the data distinctly lean toward transradial approach as the preferable option for cerebral angiography. The advantages of transradial approach, highlighted by its lower complication rates, especially major complications, suggest that its adoption could contribute to enhanced patient safety and procedural outcomes.

Distal versus conventional transradial access for diagnostic cerebral angiography and neurointerventional procedures: A systematic review and meta-analysis

BACKGROUND

Distal transradial artery access (dTRA) has received increasing consideration for performing diagnostic cerebral angiography and neurointerventional procedures. In this meta-analysis, we aim to evaluate the safety and efficacy of dTRA compared to conventional transradial access (cTRA) for cerebral angiography and neurointerventions.

METHOD

A systematic review and meta-analysis were conducted on studies investigating outcomes of dTRA and cTRA in neurointerventions. The primary outcome was technical success rates. Secondary outcomes included access site complication rates, crossover rates to alternative vessels, fluoroscopy time, and contrast volume. The random effects model was used to calculate the mean difference (MD) and odds ratios (OR) with 95% confidence intervals (Cl).

RESULTS

Eight retrospective observational studies with a total of 1477 patients who underwent 1175 diagnostic cerebral angiography and 516 neurointerventional procedures using 546 dTRA and 1164 cTRA approaches were included in our meta-analysis. The technical success rate was similar between dTRA and cTRA groups (95.8% vs 91.4%; OR:1.65; 95% Cl: 0.52 to 5.22; P = 0.40). Similarly, no difference was seen in dTRA and cTRA regarding access site complications (2% vs 1.4%; OR: 1.31; 95% CI: 0.47 to 3.61; P = 0.61) and access site crossover (2.1% vs 5.3%; OR: 0.55; 95% Cl: 0.28 to 1.05; P = 0.07). After resolving heterogeneity among included studies, dTRA was associated with a shorter fluoroscopy time (MD: -0.91 min; 95% CI: -1.74 to -0.09; P = 0.03) and lower contrast volume (MD: -8.32 mL; 95% CI = -14.7 to -1.94; P = 0.011).

CONCLUSION

Our findings suggest that the dTRA approach is a safe and effective alternative to the cTRA approach in patients undergoing cerebral angiography and neurointerventions.

Image Quality and Radiation Dose of Conventional and Wide-Field High-Resolution Cone-Beam Computed Tomography for Cerebral Angiography: A Phantom Study

There has been an increase in the use of interventional neuroradiology procedures because of their non-invasiveness compared to surgeries and the improved image quality of fluoroscopy, digital subtraction angiography, and rotational angiography. Although cone-beam computed tomography (CBCT) images are inferior to multi-detector CT images in terms of low-contrast detectability and lower radiation doses, CBCT scans are frequently performed because of their accessibility. This study aimed to evaluate the image quality and radiation dose of two different high-resolution CBCTs (HR CBCT): conventional (C-HR CBCT) and wide-field HR CBCT (W-HR CBCT). The modulation transfer function (MTF), noise power spectrum (NPS), and contrast-to-noise ratio (CNR) were used to evaluate the image quality. On comparing the MTF of C-HR CBCT with a 256 × 256 matrix and that of W-HR CBCT with a 384 × 384 matrix, the MTF of W-HR CBCT with the 384 × 384 matrix was larger. A comparison of the NPS and CNR of C-HR CBCT with a 256 × 256 matrix and W-HR CBCT with a 384 × 384 matrix showed that both values were comparable. The reference air kerma values were equal for C-HR CBCT and W-HR CBCT; however, the value of the kerma area product was 1.44 times higher for W-HR CBCT compared to C-HR CBCT. The W-HR CBCT allowed for improved spatial resolution while maintaining the image noise and low-contrast detectability by changing the number of image matrices from 256 × 256 to 384 × 384. Our study revealed the image characteristics and radiation dose of W-HR CBCT. Given its advantages of low-contrast detectability and wide-area imaging with high spatial resolution, W-HR CBCT may be useful in interventional neuroradiology for acute ischemic stroke.

Transradial Access Failures During Neuroangiography for Patients With Moyamoya

BACKGROUND

Despite studies continuing to demonstrate the utility of transradial access (TRA) in neuroangiography, minimal data exist regarding predictors of TRA failure. Furthermore, although many patients with moyamoya disease/syndrome will require life-long angiographic evaluation, even less has been reported on the usage of TRA in this population.

OBJECTIVE

To perform a matched analysis at our high-volume moyamoya center to determine predictors of TRA failure in these patients.

METHODS

A total of 636 patients undergoing TRA for neuroangiography were identified from 2018 to 2020. Demographic and angiographic characteristics including radial artery spasm (RAS), radial anomalies, and access site conversion were compared between patients with moyamoya and the rest of the cohort. A 4:1 matched analysis, based on age and sex, was also performed to eliminate confounding variables.

RESULTS

Patients with moyamoya were younger (40 vs 57 years, P < .0001), had smaller radial diameters (1.9 vs 2.6 mm, P < .0001), more commonly had a high brachial bifurcation (25.9% vs 8.5%, P = .008), more frequently experienced clinically significant RAS (40% vs 8.4%, P < .0001), and more often required access site conversion (26.7% vs 7.8%, P = .002). Increasing age was associated with less TRA failures in patients with moyamoya (odds ratio = 0.918) but more failures in the rest of the cohort (odds ratio = 1.034). In the matched analysis, patients with moyamoya continued to experience more radial anomalies, RAS, and access site conversions.

CONCLUSION

Patients with moyamoya, when controlling for age and sex, have higher rates of TRA failure during neuroangiography. Increasing age in Moyamoya is inversely correlated with TRA failures suggesting that younger patients with moyamoya are at higher risk of extracranial arteriopathy.

Endovascular management of intracranial aneurysms at Chris Hani Baragwanath Academic Hospital

Background

Worldwide, intracranial aneurysms are associated with a high mortality rate. While endovascular management has proven to be the choice of treatment in selected patients, patient demographics and aneurysm characteristics differ between study populations.

Objectives

This study aimed to investigate the profile of patients with intracranial aneurysms who underwent endovascular management in the Interventional Neuroradiology Unit at Chris Hani Baragwanath Academic Hospital. Patient demographics, risk factors, indications, aneurysm characteristics and intra-operative complications were studied.

Method

This was a 3-year retrospective study of all adult patients between 01 January 2018 and 31 January 2021. The Chi-square test was used to compare categorical variables.

Results

A total of 77 patients were included in this study. The mean age of the patients was 47 ± 11.6 with a male-to-female ratio of 1:1.8. Hypertension was the most reported risk factor in 27% of patients. There was no statistical correlation between the gender groups according to presentation, multiplicity, aneurysmal size dimensions and locations. According to the presentation, there was statistical significance in ruptured intracranial aneurysms (p = 0.020), neck size dimensions less than 4 mm (p = 0.010), and aneurysms located in the internal cerebral artery (ICA) circulation (p = 0.001).

Conclusion

The study findings support known parameters including females and anterior circulation aneurysm preponderance, and the low complication risk of endovascular management. Interestingly, intracranial aneurysms presented with rupture at smaller size dimensions.

Contribution

This study provides valuable insights into intracranial aneurysm characteristics and endovascular management efficacy in a resource-limited setting.

Understanding development of jugular bulb stenosis in vein of galen malformations: identifying metrics of complex flow dynamics in the cerebral venous vasculature of infants

Introduction: Computational fluid dynamics (CFD) assess biological systems based on specific boundary conditions. We propose modeling more advanced hemodynamic metrics, such as core line length (CL) and critical points which characterize complexity of flow in the context of cerebral vasculature, and specifically cerebral veins during the physiologically evolving early neonatal state of vein of Galen malformations (VOGM). CFD has not been applied to the study of arteriovenous shunting in Vein of Galen Malformations but could help illustrate the pathophysiology of this malformation. Methods: Three neonatal patients with VOGM at Boston Children's Hospital met inclusion criteria for this study. Structural MRI data was segmented to generate a mesh of the VOGM and venous outflow. Boundary condition flow velocity was derived from PC-MR sequences with arterial and venous dual velocity encoding. The mesh and boundary conditions were applied to model the cerebral venous flow. We computed flow variables including mean wall shear stress (WSSmean), mean OSI, CL, and the mean number of critical points (nCrPointsmean) for each patient specific model. A critical point is defined as the location where the shear stress vector field is zero (stationary point) and can be used to describe complexity of flow. Results: The division of flow into the left and right venous outflow was comparable between PC-MR and CFD modeling. A high complexity recirculating flow pattern observed on PC-MR was also identified on CFD modeling. Regions of similar WSSmean and OSImean (<1.3 fold) in the left and right venous outflow channels of a single patient have several-fold magnitude difference in higher order hemodynamic metrics (> 3.3 fold CL, > 1.7 fold nCrPointsmean). Specifically, the side which developed JBS in each model had greater nCrPointsmean compared to the jugular bulb with no stenosis (VOGM1: 4.49 vs. 2.53, VOGM2: 1.94 vs. 0, VOGM3: 1 vs. 0). Biologically, these regions had subsequently divergent development, with increased complexity of flow associating with venous stenosis. Discussion: Advanced metrics of flow complexity identified in computational models may reflect observed flow phenomena not fully characterized by primary or secondary hemodynamic parameters. These advanced metrics may indicate physiological states that impact development of jugular bulb stenosis in VOGM.

Primary central nervous system vasculitis: a diagnostic and therapeutic challenge. A series of 7 patients

INTRODUCTION

Primary central nervous system vasculitis (PCNSV) is a rare disease affecting medium- and small-calibre blood vessels of the central nervous system.

OBJECTIVE

The aim of this study was to analyse clinical findings and diagnostic aspects, with special attention to histopathological findings, as well as the treatments used and treatment response in patients diagnosed with PCNSV at our hospital.

PATIENTS AND METHODS

We conducted a retrospective descriptive analysis of patients with a diagnosis of PCNSV at discharge from our centre and meeting the 1988 Calabrese criteria. To this end, we analysed the hospital discharge records of Hospital General Universitario de Castellón between January 2000 and May 2020.

RESULTS

We analysed a series of 7 patients who were admitted with transient focal alterations and other less specific symptoms such as headache or dizziness; diagnosis was based on histological findings in 5 cases and on suggestive arteriographic findings in the remaining 2. Neuroimaging results were pathological in all cases, and CSF analysis detected alterations in 3 of the 5 patients who underwent lumbar puncture. All patients received initial treatment with megadoses of corticosteroids followed by immunosuppressive treatment. Progression was unfavorable in 6 cases, with fatal outcomes in 4.

CONCLUSIONS

Despite the diagnostic challenge of PCNSV, it is essential to attempt to reach a definitive diagnosis using such tools as histopathology and/or arteriography studies, in order to promptly establish appropriate treatment and thus reduce the morbidity and mortality of this condition.

[Rapidly progressive intracranial large artery aterosclerosis, a rare stroke etiology]

INTRODUCTION

Intracranial atheromatosis is one of the most frequent causes of stroke. It is usually a slowly progressive process and normally associated with the sum of vascular risk factors.

CASE REPORT

In this case we present a rapidly progressive development of intracranial atheromatosis demonstrated by serial neuroimaging techniques and sample analysis in a 72-year-old female patient with high levels of interleukin-6 and C-reactive protein, with no signs of vasculitis.

CONCLUSION

Rapidly progressive intracranial atheromatosis should be considered in adult patients over 50 years of age with recurrent stroke.

The Clinical Impact of Recent Methamphetamine Exposure in Aneurysmal Subarachnoid Patients

Background

Methamphetamines (MA) are a frequently used drug class with potent sympathomimetic properties that can affect cerebral vasculature. Conflicting reports in literature exist about the effect of exposure to MA on vasospasm risk and clinical outcomes in aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to characterize the impact of recent MA use on the timing, severity and features of vasospasm in aneurysmal subarachnoid as well as neurological outcomes.

Methods

We retrospectively screened 441 consecutive patients admitted to a tertiary care hospital with a diagnosis of SAH who underwent at least one cerebral digital subtraction angiogram (DSA). Patients were excluded if no urinary toxicology screen was performed within 24 hours of admission, if there was a diagnosis of non-aneurysmal SAH, or if ictus was greater than 72 hours from hospital admission. Vasospasm characteristics were collected from DSA and transcranial doppler (TCD) studies and demographic as well as clinical outcome data was abstracted from the chart.

Results

129 patients were included and 24 tested positive for MA. Among the 312 excluded patients, 281 did not have a urinary toxicology screen and 31 had a non-aneurysmal pattern of SAH or ictus occurring greater than 72 hours from hospital admission. No significant differences were found in respect to patient age, sex, or admission Hunt and Hess Score or Modified Fisher Scale based on MA use. There was no difference in the severity of vasospasm or time to peak severity using either TCD or DSA criteria on multivariate analysis. Aneurysms were more likely to be in the anterior circulation for both groups, however the MA cohort experienced less vasospasm involving the anterior circulation and more isolated posterior circulation vasospasm. There was no difference in delayed cerebral ischemia (DCI) incidence, length of ICU stay, need for ventriculoperitoneal shunt placement, functional outcome at discharge or hospital mortality.

Interpretation

Recent MA use was not associated with worse vasospasm severity, time to vasospasm, or DCI in aSAH patients. Further investigations about localized MA effects in the posterior circulation and impact on long-term functional outcomes are warranted.

Development of technical skills in simulated cerebral aneurysm coiling

Endovascular surgical procedures require visual-spatial coordination in workspaces with restricted motions and temporally limited imaging. The development of the skills needed for these procedures can be facilitated by 3D simulator-based training. Cerebral angiography (CA) has lagged behind in this training approach due to the lack of validated, realistic training models, relying strictly on clinical case exposure frequency ("number of hours logged") as a means of assessing proficiency. The ANGIO Mentor visual-haptic simulator is regarded as an effective training tool, however, this simulator has not been tested thoroughly in its ability to train interventional skills. In particular, the details of the aneurysm coiling process during simulation-based training have not been assessed. In this study, 12 novice medical students were given simulation-based diagnostic CA training until a procedural plateau in performance, established in our previous work. Subsequently, they were trained using video tutorials and written instructions to identify, measure and intervene with cerebral aneurysms using endovascular coils. Over the span of 6 sessions, participants were assessed on their procedural task time, coiling quantity and quality, and perforation rates. Prior to commencing the study, participant spatial ability was assessed using a mental rotation test (MRT) and used as a comparative baseline for the performance analysis. We found that all individuals were able to perform the procedure faster after 6 sessions, reducing their average time from 42 to 24 minutes. Coil success rate improved over from 82% to 88% and coil packing rate remained consistent at 30% throughout testing. High perforation rate seen at the start of the study showed a trend of decreasing over the latter sessions, however, over half of aneurysms were still being perforated by the novice participants. No change in aneurysm coiling quality was found, with a slight decrease in number of parent artery coil protrusions. High MRT individuals were better able to establish necessary tools prior to coiling, however, no other MRT-specific changes were seen. This work identifies the utility of simulation-based CA training in identifying the particular difficulties trainees experience in learning procedural skills, including prevention of perforations, proper positioning and success of coils within the aneurysm.

Comparing Radiation Dose of Cerebral Angiography Using Conventional and High kV Techniques: A Retrospective Study on Intracranial Aneurysm Patients and a Phantom Study

Evaluation of patient radiation dose after the implementation of a high kV technique during a cerebral angiographic procedure is an important issue. This study aimed to determine and compare the patient radiation dose of intracranial aneurysm patients undergoing cerebral angiography using the conventional and high kV techniques in a retrospective study and a phantom study. A total of 122 cases (61 cases with conventional technique and 61 cases with high kV technique) of intracranial aneurysm patients, who underwent cerebral angiographic procedure and met the inclusion criteria, were recruited. The radiation dose and the angiographic exposure parameters were reviewed retrospectively. The radiation dose in the phantom study was conducted using nanoDot^TM optically stimulating luminescence (OSLD), which were placed on the scalp of the head phantom, the back of the neck, and the phantom skin at the position of the eyes. The standard cerebral angiographic procedure using the conventional and high kV techniques was performed following the standard protocol. The results showed that the high kV technique significantly reduced patient radiation dose and phantom skin dose. This study confirms that the implementation of a high kV technique in routine cerebral angiography for aneurysm diagnosis provides an effective reduction in radiation dose. Further investigation of radiation dose in other interventional neuroradiology procedures, particularly embolization procedure, should be performed.

Diagnosis, Workup, Risk Reduction of Transient Ischemic Attack in the Emergency Department Setting: A Scientific Statement From the American Heart Association

At least 240 000 individuals experience a transient ischemic attack each year in the United States. Transient ischemic attack is a strong predictor of subsequent stroke. The 90-day stroke risk after transient ischemic attack can be as high as 17.8%, with almost half occurring within 2 days of the index event. Diagnosing transient ischemic attack can also be challenging given the transitory nature of symptoms, often reassuring neurological examination at the time of evaluation, and lack of confirmatory testing. Limited resources, such as imaging availability and access to specialists, can further exacerbate this challenge. This scientific statement focuses on the correct clinical diagnosis, risk assessment, and management decisions of patients with suspected transient ischemic attack. Identification of high-risk patients can be achieved through use of comprehensive protocols incorporating acute phase imaging of both the brain and cerebral vasculature, thoughtful use of risk stratification scales, and ancillary testing with the ultimate goal of determining who can be safely discharged home from the emergency department versus admitted to the hospital. We discuss various methods for rapid yet comprehensive evaluations, keeping resource-limited sites in mind. In addition, we discuss strategies for secondary prevention of future cerebrovascular events using maximal medical therapy and patient education.

A novel simulator-based checklist for evaluating residents' competence in cerebral angiography in China

Background

Nowadays, with the fast-increasing demand for neuro-endovascular therapy, surgeons in this field are in urgent need. Unfortunately, there is still no formal skill assessment in neuro-endovascular therapy in China.

Methods

We used a Delphi method to design a newly objective checklist for standards of cerebrovascular angiography in China and evaluated its validity and reliability. A total of 19 neuro-residents with no interventional experience and 19 neuro-endovascular surgeons from two centers (Guangzhou and Tianjin) were recruited; they were divided into two groups: residents and surgeons. Residents completed a simulation-based cerebrovascular angiography operation training before assessment. Assessments were under live and video record forms with two tools: the existing global rating scale (GRS) of endovascular performance and the new checklist.

Results

The average scores of residents were significantly increased after training in two centers (p < 0.05). There is good consistency between GRS and the checklist (p = 0.856). Intra-rater reliability (Spearman's rho) of the checklist was >0.9, and the same result was also observed in raters between different centers and different assessment forms (p < 0.001, rho > 0.9). The reliability of the checklist was higher than that of the GRS (Kendall's harmonious coefficient is 0.849, while GRS is 0.684).

Conclusion

The newly developed checklist appears reliable and valid for evaluating the technical performance of cerebral angiography and differentiating between trained and untrained trainees' performance well. For its efficiency, our method has been proven to be a feasible tool for resident angiography examination in certification nationwide.

Aberrant Origin of the Distal Anterior Cerebral Artery from the Middle Cerebral Artery Related to Obstruction of Bilateral Proximal Anterior Cerebral Arteries: A Case Report

BACKGROUND

Aberrant origin of the distal anterior cerebral artery (ACA) arising from the middle cerebral artery (MCA) is extremely rare.

CASE PRESENTATION

A 74-year-old woman with a sudden onset of left-sided weakness was admitted to the emergency department. Angiography revealed an unusual course of the distal ACA originating from the MCA with bilateral obstruction of the proximal segment of the ACA and simultaneous occurrence of infarction in the ACA and MCA territories.

CONCLUSION

Knowledge of a rare vascular variation or anomaly could help understand brain imaging, which has an unusual involvement of vascular territories, performed in patients with acute ischemic stroke.

Congenital internal carotid artery hypoplasia: A systematic review

This review evaluates the current evidence for the clinical management of congenital internal carotid artery hypoplasia (CICAH). We summarise clinical presentations diagnostic standards, imaging recommendations, treatment and follow-up. The review was prompted by a case of CICAH in a 50-year-old female who presented to our neurosurgery clinic with an acute episode of vertigo. The patient underwent CT angiogram, which showed an unusually low right carotid bifurcation. The right internal carotid artery (ICA) was hypoplastic, and the A1 segment of the anterior cerebral artery (ACA) was absent. Skull base CT showed an ipsilateral hypoplastic carotid canal. To summarise current evidence for clinical management of CICAH we followed PRISMA guidelines to identify papers meeting our predefined inclusion criteria. We searched three databases using the terms 'ICA' and 'Hypoplasia'. We reviewed 41 papers meeting our criteria. 34 were clinical reports. We performed a data extraction and quality appraisal on these reports. We found that CICAH may be less rare than previously described. Blood pressure control in CICAH is crucial due to the increased risk of stroke and aneurysm formation. Follow-up imaging is strongly recommended. Carotid doppler sonography is a powerful and underutilised diagnostic tool, and carotid canal hypoplasia is not a pathognomic sign. In conclusion, clinicians should be alert to anatomic variations such as CICAH because these produce haemodynamic changes that may have serious clinical consequences. We recommend a central registry of patients with CICAH in order to understand the longer-term natural history of the condition.

Thalamic structure and anastomosis in different hemispheres of moyamoya disease

Objective

The progression of the asymptomatic hemisphere of moyamoya disease (MMD) is largely unknown. In this study, we investigated the differences in subcortical gray matter structure and angiographic features between asymptomatic and symptomatic hemispheres in patients with MMD.

Methods

We retrospectively reviewed patients with MMD in consecutive cases in our center. We compared subcortical gray matter volume and three types of collaterals (lenticulostriate anastomosis, thalamic anastomosis, and choroidal anastomosis) between symptomatic and asymptomatic hemispheres. Symptomatic hemispheres were classified as ischemic hemisphere (i-hemisphere) and hemorrhagic hemisphere (h-hemisphere). Asymptomatic hemispheres were classified as contralateral asymptomatic hemisphere of i-hemisphere (ai-hemisphere), contralateral asymptomatic hemisphere of h-hemisphere (ah-hemisphere), bilateral asymptomatic hemispheres in asymptomatic group (aa-hemisphere).

Results

A total of 117 MMD patients were reviewed, and 49 of them met the inclusion criteria, with 98 hemispheres being analyzed. The thalamic volume was found to differ significantly between the i- and ai-hemispheres (P = 0.010), between the i- and ah-hemispheres (P = 0.004), as well as between the h- and ai-hemispheres (P = 0.002), between the h- and ah-hemispheres (P < 0.001). There was a higher incidence of thalamic anastomosis in the ai-hemispheres than i-hemispheres (31.3% vs. 6.3%, P = 0.070), and in the ah-hemispheres than h-hemispheres (29.6% vs. 11.1%, P = 0.088). Additionally, the hemispheres with thalamic anastomosis had a significantly greater volume than those without thalamic anastomosis (P = 0.024). Univariate and multivariate logistic regression analysis showed that thalamic volume was closely associated with thalamic anastomosis.

Conclusion

The thalamic volume and the incidence of thalamic anastomosis increase in asymptomatic hemispheres and decrease in symptomatic hemispheres. Combining these two characteristics may be helpful in assessing the risk of stroke in the asymptomatic hemispheres of MMD as well as understanding the pathological evolution of the disease.

Contrast-induced encephalopathy and permanent neurological deficit following cerebral angiography: A case report and review of the literature

Contrast-induced encephalopathy (CIE) is an uncommon complication associated with contrast exposure during angiographic procedures that is usually transient but occasionally leads to permanent complications or death. Due to the low incidence of CIE, there are still insufficient reports. This study was used to summarize the clinical features of CIE through a case report and systematic review. We summarized and reviewed 127 patients with CIE, and we found that the total incidence of CIE between men and women had no difference (49.61 and 50.39%, respectively), but the average age in female patients with CIE was older than that in male patients (62.19 and 58.77 years, respectively). Interestingly, the incidence of female patients with CIE in the poor prognosis group was significantly higher than that in the good prognosis group (62.50 and 36.51%, respectively), and the average age of these female patients in the poor prognosis group was younger than that in the good prognosis group (61.39 and 62.82 years, respectively). The contrast medium types were mainly nonionic (79.69 and 73.02%, respectively) and low-osmolar (54.69 and 71.43%, respectively) in both groups. Importantly, the total contrast media administrated in patients with poor prognoses was greater than that administrated in patients with good prognoses (198.07 and 188.60 ml, respectively). In addition, comorbidities in both groups included hypertension (55.91%), diabetes mellitus (20.47%), previous contrast history (15.75%), renal impairment (11.81%), and hyperlipidemia (3.15%). The percentage of patients with cerebral angiography was significantly higher in the poor prognosis group than that in the good prognosis group (37.50 and 9.52%, respectively), whereas the percentage of patients with coronary angiography in both groups had the opposite results (35.94 and 77.78%, respectively). In conclusion, CIE may not always have a benign outcome and can cause permanent deficits. Female gender, younger age, the higher dose of contrast medium, and the procedure of cerebral angiography may be related to the patient's poor prognosis.

Case report: An overlooked complication of the dural suture after craniotomy: pseudoaneurysm of the middle meningeal artery with endovascular resolution

Aneurysms of the middle meningeal artery (MMA) are exceedingly uncommon and mainly result from traumatic brain damage, but this report describes a case of MMA aneurysm induced by cranial surgery. Surgery was performed on a 34-year-old male with cerebrovascular malformation and cerebral hemorrhage. Cerebral angiography revealed no MMA aneurysm before craniocerebral surgery; however, a postoperative angiogram revealed a new MMA aneurysm. Aneurysms of the MMA are uncommon consequences of brain surgery. Based on our findings, the MMA as well as other meningeal arteries should be avoided while suturing the dura mater tent to prevent aneurysms.

Fluorescently-tagged magnetic protein nanoparticles for high-resolution optical and ultra-high field magnetic resonance dual-modal cerebral angiography

Extremely small paramagnetic iron oxide nanoparticles (FeMNPs) (<5 nm) can enhance positive magnetic resonance imaging (MRI) contrast by shortening the longitudinal relaxation time of water (T₁), but these nanoparticles experience rapid renal clearance. Here, magnetic protein nanoparticles (MPNPs) are synthesized from protein-conjugated citric acid coated FeMNPs (c-FeMNPs) without loss of the T₁ MRI properties and tagged with fluorescent dye (f-MPNPs) for optical cerebrovascular imaging. The c-FeMNPs shows average size 3.8 ± 0.7 nm with T₁ relaxivity (r₁) of 1.86 mM^-1 s^-1 and transverse/longitudinal relaxivity ratio (r₂/r₁) of 2.53 at 11.7 T. The f-MPNPs show a higher r₁ value of 2.18 mM^-1 s^-1 and r₂/r₁ ratio of 2.88 at 11.7 T, which generates excellent positive MRI contrast. In vivo cerebral angiography with f-MPNPs enables detailed microvascular contrast enhancement for differentiation of major blood vessels of murine brain, which corresponds well with whole brain three-dimensional time-of-flight MRI angiograms (17 min imaging time with 60 ms repetition time and 40 μm isotropic voxels). The real-time fluorescence angiography enables unambiguous detection of brain capillaries with diameter < 40 μm. Biodistribution examination revealed that f-MPNPs were safely cleared by the organs like the liver, spleen, and kidneys within a day after injection. Blood biochemical assays demonstrated no risk of iron overload in both rats and mice. With hybrid neuroimaging technologies (e.g., MRI-optical) on the rise, f-MPNPs built on this platform can generate exciting neuroscience applications.

Duplication of the internal maxillary artery: Anatomical and clinical considerations

Duplication of the internal maxillary artery (IMAX) results from a failed regression of either the embryological superficial or deep ring and is reported to be exceedingly rare. We present a patient with this rare anatomical variant who was treated by endovascular technique in the clinical context of an acute oropharyngeal hemorrhage.

Development of a Nomogram for Predicting Asymptomatic Coronary Artery Disease in Patients with Ischemic Stroke

BACKGROUND

Coronary artery stenosis (CAS) ≥50% often coexists in patients with ischemic stroke, which leads to a significant increase in the occurrence of major vascular events after stroke. This study aimed to develop a nomogram for diagnosing the presence of ≥50% asymptomatic CAS in patients with ischemic stroke.

METHODS

A primary cohort was established that included 275 non-cardioembolic ischemic stroke patients who were admitted from January 2011 to April 2013 to a teaching hospital in southern China. The preoperative data were used to construct two models by the best subset regression and the forward stepwise regression methods, and a nomogram between these models was established. The assessment of the nomogram was carried out by discrimination and calibration in an internal cohort.

RESULTS

Out of the two models, model 1 contained eight clinical-related variables and exhibited the lowest Akaike Information Criterion value (322.26) and highest concordance index 0.716 (95% CI, 0.654-0.778). The nomogram showed good calibration and significant clinical benefit according to calibration curves and the decision curve analysis.

CONCLUSION

The nomogram, composed of age, sex, NIHSS score on admission, hypertension history, fast glucose level, HDL cholesterol level, LDL cholesterol level, and presence of ≥50% cervicocephalic artery stenosis, can be used for prediction of ≥50% asymptomatic coronary artery disease (CAD). Further studies are needed to validate the effectiveness of this nomogram in other populations.

Hidden Telltale Signs in Hyperacute Ischemic Stroke Caused by Aortic Dissection: A Case Report and Post Hoc Analysis

INTRODUCTION

Rapid identification of hidden telltale signs in hyperacute ischemic stroke caused by aortic dissection (AD) is challenging, mainly owing to the narrow time window for bridging therapy.

CASE REPORT

A 63-year-old man was referred for sudden right-side weakness accompanied by a decreased level of consciousness for almost 1 hour and 37 minutes. He had a history of hypertension. His skin was clammy, and on physical examination, there was involuntary chest thumping in the left upper limb. Hyperacute cerebral infarction was considered after no bleeding was observed on emergency head computed tomography, and intravenous thrombolysis with alteplase was administered immediately after. The patient was then taken to the catheter room, ready for endovascular thrombectomy. Stanford type A AD was found by cerebral angiography before endovascular thrombectomy. The infusion of alteplase was stopped immediately during cerebral angiography, but the patient's blood pressure, heart rate, and blood oxygen were still declining progressively, and the degree of consciousness disturbance deepened. The patient died after the combined but failed rescue attempts of multiple departments.

CONCLUSION

Hyperacute ischemic stroke caused by AD often hides some telltale signs. Clinicians should master basic clinical skills to exclude AD by looking for these telltale signs hidden in hyperacute ischemic stroke to avoid the fatal consequences of intravenous thrombolysis and/or cerebral angiography within the narrow window of time.

Vertebral artery dissection induced lateral medullary syndrome characterized with severe bradycardia: a case report and review of the literature

BACKGROUND

Lateral medullary syndrome is the most common type of brainstem infarction. Lateral medullary syndrome results in damage to the corresponding cranial nerve nuclei and the nucleus tractus solitarius, with vertigo, ipsilateral ataxia, crossed sensory disturbances, Horner's sign, bulbar palsy, and other underlying symptoms or signs. However, cases with cardiac arrhythmia and other autonomic dysfunctions as the primary manifestations are less common. Clinically, sudden death occasionally occurs in patients with lateral medullary syndrome, which may be associated with severe cardiac arrhythmia. These patients may suffer in life-threatening arrhythmia and even cardiac arrest, and vital signs should be closely monitored to prevent sudden death. In younger patients, vertebral artery dissection is the most common cause.

CASE DESCRIPTION

Here, we present a case of lateral medullary syndrome caused by vertebral artery dissection with severe bradycardia. The patient was a 49-year-old man who was admitted with "sudden onset of numbness in the left limbs and right side of the face for 1 hour". Electrocardiogram (ECG) monitoring showed a repeated heart rate decrease to as low as 23 beats/min, followed by a gradual increase in heart rate to 35-55 beats/min after 2-3 seconds. Head magnetic resonance imaging (MRI) examination revealed right dorsolateral cerebral infarction of the medulla oblongata. Digital subtraction angiography (DSA) revealed a right vertebral artery dissecting aneurysm. We performed an emergency placement of a temporary pacemaker, followed by conservative treatment with platelet aggregation inhibitors, vascular softening agents and improved collateral circulation. Elective spring coil embolization of the vertebral artery dissecting aneurysm and stent implantation were performed. At outpatient follow-up, the patient had a good prognosis.

CONCLUSIONS

Clinical management of patients with lateral medullary syndrome should be prioritized, with close cardiac monitoring at the early stages of observation and pacemaker placement and tracheal intubation as required to prevent adverse events.

Sequential Flow Diversion After Nitinol Stent Placement for a Large, Matricidal Cavernous Internal Carotid Artery Aneurysm: Technical Video

The Surpass Evolve flow diverter is a novel 64-wire braided intravascular stent approved to treat unruptured large or giant saccular wide-neck or fusiform intracranial aneurysms of the intracranial internal carotid artery.1-3 Flow diverting stents have been used for the treatment of previously stented aneurysms, including residual aneurysms following prior flow diversion.5-8 This patient initially presented with a large symptomatic matricidal cavernous ICA aneurysm4 that was treated with stand-alone Neuroform Atlas stenting at an outside hospital. Here we present a video demonstrating the placement of sequential Surpass Evolve flow diverter stents within a Neuroform Atlas nitinol stent.

Transradial access for cerebral angiography and neurointerventional procedures: A meta-analysis and systematic review

PURPOSE

Transradial access (TRA) for diagnostic and interventional neurointerventional procedures has recently gained traction over transfemoral access (TFA) in the neurointerventional community. This meta-analysis aims to assess and summarize the utility of TRA in cerebral angiography and neurointerventional procedures.

METHODS

A systematic literature review was performed utilizing Pubmed, Embase, and Scopus databases. Using PRISMA guidelines, records were extracted with the following search terms: transradial approach, transradial access, radial access, cerebral angiogram, cerebral angiography, neurointervention, and neuroendovascular. The primary outcomes assessed were case success rate, complication rate, and crossover rate from TRA to TFA. Secondary analysis was performed on procedure time, fluoroscopy time, fluoroscopy time per vessel (diagnostic procedures only), contrast dose, radial artery diameter, distal radial artery diameter, and patient preference for TRA over TFA.

RESULTS

Sixty-two full-text articles were analyzed for this meta-analysis, representing 12,927 diagnostic and interventional TRA access patients. Our analysis revealed a combined diagnostic and interventional case success rate of 95.9% and complication rate of 3.5%, with crossover to TFA occurring in 4.9% of cases.

CONCLUSION

This meta-analysis demonstrates that TRA access for diagnostic angiography and neurointerventional procedures is a safe and effective approach, though determining a true complication rate is challenging as the definition of TRA complications has changed in various publications over time.

Diagnostic Criteria for Moyamoya Disease - 2021 Revised Version

In this report, we, the Research Committee on Moyamoya Disease (Spontaneous Occlusion of the circle of Willis), describe in detail the changes in the new “Diagnostic Criteria 2021” for moyamoya disease and its scientific basis to make it widely known to the world. The revised criteria cover all aspects of the disease, including a definition of the disease concept, diagnostic imaging, and the concept of quasi-moyamoya disease (moyamoya syndrome).

Transdural Revascularization by Multiple Burrhole After Erythropoietin in Stroke Patients With Cerebral Hypoperfusion: A Randomized Controlled Trial

In patients with acute symptomatic stroke, reinforcement of transdural angiogenesis using multiple burr hole (MBH) procedures after EPO (erythropoietin) treatment has rarely been addressed. We aimed to investigate the efficacy and safety of cranial MBH procedures under local anesthesia for augmenting transdural revascularization after EPO treatment in patients with stroke with perfusion impairments.

Contrast-induced encephalopathy following cerebral angiography: A case report

The present study describes the case of patient with contrast-induced encephalopathy following cerebrovascular angiography, and presents the clinical and imaging features, as well as the treatment and prognosis of this patient. Following digital subtraction angiography, cortical blindness and cognitive dysfunction were the main complaints of the patient. The emergency craniocerebral CT scan revealed hyperdense areas in the bilateral cerebellum, thalamus, sulcus and cistern, and a review of the CT scan 24 h following the procedure revealed that the hyperintense lesions were reduced or resolved in these areas. The patient obtained a good prognosis following treatment anti-inflammatory and intracranial pressure reduction treatment. On the whole, the present study demonstrates that cognitive dysfunction may be a clinical manifestation of contrast-induced encephalopathy. Thus, the earlier diagnosis and earlier treatment are crucial for the prognosis of patients.

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.