Incidence and Characteristics of Cerebral Infarction After Microsurgical Clipping of Unruptured Anterior Circulation Cerebral Aneurysms: Diffusion-Weighted Imaging-Based Analysis of 600 Patients

BACKGROUND AND OBJECTIVES

Postclipping cerebral infarction (PCI) remains a major concern after treatment for unruptured intracranial aneurysms (UIAs). However, studies of microsurgical clipping based on diffusion-weighted imaging are limited. We aimed to present the incidence, risk factors, and types of PCI and its radiological and clinical characteristics.

METHODS

This was a retrospective single-center study in which patients were scheduled to undergo microsurgical clipping for anterior circulation UIAs. The overall incidence and risk factors were calculated. Based on the operation and relevant artery, we categorized PCI on diffusion-weighted imaging into 4 types and presented their radiological and clinical characteristics.

RESULTS

We reviewed the radiological and clinical data of 605 patients. The overall incidence of PCI was 16.7% (101/605), of which asymptomatic infarction was 14.9% (90/605) and symptomatic infarction was 1.8% (11/605). Hypertension (adjusted odds ratio [aOR], 2.258; 95% confidence interval [CI]: 1.330-3.833), temporary clipping (aOR, 1.690; 95% CI: 1.034-2.760), multiple aneurysm locations (aOR, 1.832; 95% CI: 1.084-3.095), and aneurysm dome size (aOR, 1.094; 95% CI: 1.006-1.190) were independent risk factors for PCI. Type II (perianeurysmal perforator) infarction was the most common type of PCI (48.6%) and the most common cause of symptomatic infarction (72.7%). Types II and III (distal embolic) infarctions correlated with atherosclerotic changes in the aneurysm wall and temporary clipping (62.4% and 70.6%, respectively). The type IV (unrelated) infarction group had a higher incidence of systemic atherosclerosis (55%).

CONCLUSION

Microsurgical clipping is a safe and viable option for the treatment of anterior circulation UIAs. However, modification of the surgical technique, preoperative radiological assessment, and patient selection are required to reduce the incidence of PCI.

Advances in Intraoperative Imaging for Vascular Neurosurgery

Cerebrovascular surgery has many intraoperative imaging modalities available. Modern technologies include intraoperative digital subtraction angiogram, indocyanine green (ICG) angiography, relative fluorescent measurement with ICG, and ultrasound. Each of these can be used effectively in the treatment of open aneurysm and arteriovenous malformation surgeries, in addition to arteriovenous fistula surgery, and cerebral bypass surgery.

Treatment of a Patient With Meningioma With Complicated Blood Supply

Meningiomas account for ~30% of primary intracranial tumors, making them the second most common type of brain tumor. Most meningiomas are benign, and surgical resection is curative. By utilizing 3-dimensional slicer technology for multimodal image fusion, a wealth of 3-dimensional anatomic information can be obtained, enabling more effective treatment of meningiomas with complex tumor locations and surrounding structures. Guided by the 3-dimensional structural models, we conducted detailed preoperative planning for 1 case of highly vascularized meningioma and utilized combined surgery for complete tumor removal, effectively avoiding intraoperative bleeding and postoperative complications.

Evaluation of Serial Intra-Arterial Indocyanine Green Videoangiography in the Surgical Treatment of Cranial and Craniocervical Junction Arteriovenous Fistulae: A Case Series

BACKGROUND AND OBJECTIVES

Intravenous indocyanine green (IV-ICG) videoangiography is commonly performed to detect blood flow in the microscopic view. However, intra-arterial ICG (IA-ICG) videoangiography provides high-contrast imaging, repeatability within a short period of time, and clear-cut separation of the arterial and venous phases compared with IV-ICG. These features are useful for detecting retrograde venous drainage (RVD) and shunt occlusion in arteriovenous fistulae (AVF) surgery. This study aimed to investigate whether IA-ICG videoangiography can be repeatable within a short period of time and be useful for detecting RVD and shunt occlusion in cranial- and craniocervical junction (CCJ)-AVF surgery.

METHODS

Between January 2012 and December 2022, 50 patients were treated with endovascular or surgical intervention for cranial- and CCJ-AVF at Tokushima University Hospital. Of these, 5 patients (6 lesions) underwent open surgery with IA-ICG videoangiography in a hybrid operating room. We analyzed the data of these 5 patients (6 lesions).

RESULTS

There were 4/patient (median, range 2-12) and 3.5/lesion (median, range 2-10) intraoperative IA-ICG runs. IA-ICG videoangiography detected RVD in all patients. Clearance of IA-ICG-induced fluorescence was achieved within 30 seconds in all patients at each region of interest. After the disconnection of the fistulae, IA-ICG videoangiography and intraoperative digital subtraction angiography (DSA) confirmed the disappearance of RVD in all patients. There were no complications associated with IA-ICG videoangiography.

CONCLUSION

This study showed that IA-ICG videoangiography is repeatable within a short period of time before and after obliteration and can be useful for detecting RVD and shunt occlusion in cranial- and CCJ-AVF surgery. IA-ICG videoangiography also allows intraoperative DSA studies in a hybrid operating room. Considering the recent advancements in hybrid operating rooms, combining IA-ICG videoangiography with intraoperative DSA is a useful strategy for cranial- and CCJ-AVF surgery.

Transradial Versus Transfemoral Intraoperative Cerebral Angiography for Open Cerebrovascular Surgery: Effectiveness, Safety, and Learning Curve

BACKGROUND

Intraoperative cerebral angiography (IOA) is a valuable adjunct in open and hybrid cerebrovascular surgery. Commonly, transfemoral access (TFA) is used. Lately, transradial access (TRA) has gained popularity for neurointervention. However, the TRA has not yet been compared with the TFA for IOA.

OBJECTIVE

To compare the effectiveness and safety of the TRA and TFA for IOA. In addition, the learning curve for implementing the TRA for IOA was evaluated.

METHODS

Between July 2020 and 2022, 92/1787 diagnostic cerebral angiographies met inclusion criteria for IOA. Sheath run time to primary target vessel run time (STT), amount of contrast dye (CD), fluoroscopy time (FT), and dose-area products (DAPs) were compared between TRA and TFA, different aortic arch types, and both study years.

RESULTS

One case required transitioning from TRA to TFA (1/26, 3.8%) because of a minute proximal radial vasculature. The STT, CD, FT, and DAP were similar for the TRA (n = 25) and the TFA groups (n = 67) (p = ns). One groin hematoma (1.5%) was observed in the TFA group. No other complications or any change in modified Rankin Scale were observed. Aortic arch type II/III was associated with longer STT ( P = .032) but not CD, FT, or DAP. There was a nonsignificant decline of STTs among the TRA cases ( P = .104) but stable STTs among TFA cases ( P = .775).

CONCLUSION

The TRA and TFA represent equally effective and safe routes for IOA. In addition, expertise with the TRA can rapidly be gained and facilitates tailoring the access for IOA to patient's individual anatomy and surgeon's needs.

Noncurative microsurgery for cerebral aneurysms: a systematic review and meta-analysis of wrapping, residual, and recurrence rates

OBJECTIVE

Microsurgery for cerebral aneurysms is called definitive, yet some patients undergo a craniotomy that results in noncurative treatment. Furthermore, the overall rate of noncurative microsurgery for cerebral aneurysms is unclear. The objective of this study was to complete a systematic review and meta-analysis to quantify three scenarios of noncurative treatment: aneurysm wrapping, postclipping remnants, and late regrowth of completely obliterated aneurysms.

METHODS

A PRISMA-guided systematic literature review of the MEDLINE and Cochrane Library databases and meta-analysis was completed. Studies were included that detailed rates of aneurysm wrapping, residua confirmed with imaging, and regrowth after confirmed total occlusion. Pooled rates were subsequently calculated using a random-effects model. An assessment of statistical heterogeneity and publication bias among the included studies was also completed for each analysis, with resultant I2 values and p values determined with Egger's test.

RESULTS

Sixty-four studies met the inclusion criteria for final analysis. In 41 studies, 573/15,715 aneurysms were wrapped, for a rate of 3.5% (95% CI 2.7%-4.2%, I2 = 88%). In 43 studies, 906/13,902 aneurysms had residual neck or dome filling, for a rate of 6.4% (95% CI 5.2%-7.6%, I2 = 93%). In 15 studies, 71/2568 originally fully occluded aneurysms showed regrowth, for a rate of 2.1% (95% CI 1.2%-3.1%, I2 = 58%). Together, there was a total rate of noncurative surgery of 12.0% (95% CI 11.5%-12.5%). Egger's test suggested no significant publication bias among the studies. Meta-regression analysis revealed that the reported rate of aneurysm wrapping has significantly declined over time, whereas the rates of aneurysm residua and recurrence have not significantly changed.

CONCLUSIONS

Open microsurgery for cerebral aneurysm results in noncurative treatment approximately 12% of the time. This metric may be used to counsel patients and as a benchmark for other treatment modalities. This investigation is limited by the high degree of heterogeneity among the included studies.

Intraoperative fluorescein video angiography in intracranial aneurysm surgery: single-center, observational cohort study

The aim of this study was to compare the incidence of postoperative, surgery-related complications in patients where fluorescein video angiography (FL-VA) was performed with those operated without intraoperative verification. This is an observational cohort study including 97 patients who were selected for microsurgical clipping due to intracranial aneurysm. First 52 patients enrolled in the study were operated prior to introduction of fluorescein fluorescence in our surgical workflow. These patients were considered as controls. The study group consisted of 45 consecutive patients operated with the use of fluorescein video angiography and by the same surgical team. Outcomes in both groups were compared using non-parametric test (Mann-Whitney U). Intraoperative fluorescein video angiography revealed aneurysm remnant or inadvertent vessel occlusion in 17.8% of patients. Following clip reposition, a repeated FL-VA was performed to confirm restoration of blood flow and/or complete aneurysm obliteration. Intraoperative findings were later confirmed using computed tomography angiography (CTA). None of the patients in our study group developed surgery-related complications; whereas in the control group, aneurysm remnant was discovered in 7.7%, brain ischemia in 9.6% and both of the latter in 5.8% of patients. Difference in treatment-related outcome was statistically significant (p < 0.05). Intraoperative fluorescein video angiography successfully identified aneurysm residual and adjacent artery occlusion leading to excellent outcome following clip reposition.

Combined Endovascular and Surgical Treatment for Brain Arteriovenous Malformations in Biplanar Hybrid Operating Room

OBJECTIVE

Combined surgical and endovascular treatment for vascular disorders has become prevalent in recent years. However, reports on one-session hybrid surgery for arteriovenous malformations (AVMs) are relatively rare. The safety and efficiency of combined treatment for brain AVMs were analyzed in biplanar hybrid operating room (OR) at one stage.

METHODS

We retrospectively analyzed 20 patients with AVMs undergoing combined surgical and endovascular treatment from October 2015 to June 2018. The data for resection rate, microcatheter adhesion, surgical position and postoperative outcomes were analyzed. Total resection or near-total resection was achieved in all cases.

RESULTS

A total of 13 patients were under combined endovascular and surgical procedures, and 7 experienced surgery with intraoperative digital subtraction angiography. Sitting position was applied in 3 of them; 2 niduses in cerebellum, and 1 in parietal lobe. Compared with admission modified Rankin Scale (mRS) in all patients, postoperative 12-month mRS showed a significant decline. Besides, 3 patients experienced microcatheter adhesion after endovascular embolization, thereafter underwent surgical adhesion removal while nidus resection was done.

CONCLUSION

Combined endovascular and surgical modality in a hybrid OR at one stage provides a safe strategy for the treatment of AVMs. The biplanar hybrid neurointerventional suite is endowed with unconstrained operating angle which enables combined endovascular and surgical treatment in sitting position. It also reduces the risk of microcatheter adhesion, which enables interventional radiologists to perform aggressively.

The value of intraoperative angiography in the time of indocyanine green videoangiography in the treatment of cerebrovascular lesions: Efficacy, workflow, risk-benefit and cost analysis A prospective study

INTRODUCTION

Intraoperative digital subtraction angiography (ioDSA) allows early treatment evaluation after neurovascular procedures. However, the value and efficiency of this procedure has been discussed controversially. We have evaluated the additional value of hybrid operating room equipped with an Artis Zeego robotic c-arm regarding cost, efficiency and workflow. Furthermore, we have performed a risk-benefit analysis and compared it with indocyanine green (ICG) angiography.

METHODS

For 3 consecutive years, we examined all neurovascular patients, treated in the hybrid operating theater in a risk-benefit analysis. After using microdoppler and ICG angiography for best operative result, every patient received an additional ioDSA to look for remnants or unfavorable clip placement which might lead to a change of operating strategy or results. Furthermore, a workflow-analysis reviewing operating steps, staff positioning, costs, technical errors or complications were conducted on randomly selected cases.

RESULTS

54 patients were enrolled in the risk-benefit analysis, 22 in the workflow analysis. The average duration of a cerebrovascular operation was 4 h 58 min 2 min 35 s accounted for ICG angiography, 46 min 4 s for ioDSA. Adverse events occurred during one ioDSA. In risk-benefit analysis, ioDSA was able to detect a perfusion rest in 2 out of 43 cases (4,7%) of aneurysm surgery, which could not have been visualized by ICG angiography before. In arterio-venous-malformation (AVM) surgery, one of 11 examined patients (7,7%) showed a remnant in ioDSA and resulted in additional resection. The average cost of an ioDSA in Ulm University can be estimated with 1928,00€.

CONCLUSION

According to our results ioDSA associated complications are low. Relevant findings in ioDSA can potentially avoid additional intervention, however, due to the high costs and lower availability, the main advantage might lie in the treatment of selected patients with complexes neurovascular pathologies since ICG angiography is equally safe but associated with lower costs and better availability.

Intra-operative fluorescein videoangiography-related nephrotoxicity in intracranial aneurysm surgery: Single center, observational cohort study

OBJECTIVES

Intra-operative fluorescein video angiography (FL-VA) has been given increasing attention recently and several studies reported its high utility in neurovascular surgery. The aim of this study was to evaluate the safety of FL-VA in a prospective, single-center cohort of patients operated due to cerebral aneurysms.

PATIENTS AND METHODS

This is an observational cohort study including 150 patients operated due to intracranial aneurysms. The study group consisted of 70 consecutive patients operated with the use of fluorescein video angiography. Post-operative acute kidney injury (AKI) occurrence as well as systemic adverse reactions were reported and further compared with 80 matched controls where FL-VA was not used. Statistical analysis was performed using non-parametric tests (Fisher's exact test).

RESULTS

Post-operative AKI was observed in 17,1% of patients in the study group with only half presenting with acute functional impairment. All of these patients presented initially due to aneurysm rupture. Pre-existing renal dysfunction and hypertension occurred in 16,7% and 33,3%, respectively. No systemic complications following FL-VA were reported. When compared to matched controls, no statistically significant difference regarding AKI occurrence was observed between these two patient populations.

CONCLUSION

Intra-operative fluorescein video angiography proved to have a good safety profile in our cohort. The results of this study suggest that post-operative acute kidney injury observed in patients with subarachnoid hemorrhage is not related to fluorescein use.

Comparison of Intra- and Postoperative 3-Dimensional Digital Subtraction Angiography in Evaluation of the Surgical Result After Intracranial Aneurysm Treatment

BACKGROUND

Postoperative three-dimensional digital subtraction angiography (3D-DSA) is the gold standard in evaluating intracranial aneurysm (IA) remnants after clipping. Should intraoperative 3D-DSA image quality be equally good as postoperative 3D-DSA, it could supplant the latter as standard of care for follow-up of clipped IA.

OBJECTIVE

To directly compare the quality of assessment of clipped IA by intraoperative and postoperative 3D-DSA.

METHODS

From a prospective cohort of 221 consecutive patients who underwent craniotomy for IA treatment in a hybrid operating room, we retrospectively studied 26 patients who had both intraoperative and postoperative 3D-DSA imaging of their clipped aneurysm. Comparison of intraoperative and postoperative 3D-DSA images (blinded for review) included parameters that affected image quality and differences between the 2 periods.

RESULTS

In the 26 patients with 32 clipped IAs, the mean interval was 11 ± 7 mo between intraoperative and postoperative imaging 3D-DSA examinations. Reconstruction with multiple clips was used in 14 (44%) cases. Of 15 remnants, 9 (60%) were small (<2 mm). In comparing intraoperative and postoperative 3D-DSA, no discordance or discrepancy in assessment of the surgical result was noted for any clipped IA, and overall imaging quality was excellent for both modalities. Factors affecting minor differences in image quality were not identified.

CONCLUSION

Compared with postoperative 3D-DSA, intraoperative 3D-DSA images achieved equally high quality and effective, immediate interpretation of the surgical clipping result. With comparable imaging quality and no discordant findings, intraoperative 3D-DSA could replace postoperative 3D-DSA to become the standard of care in IA surgery.

The experience of surgery and endovascular procedure of cerebrovascular disease in the hybrid operating room; Multi-axis robotic C-arm DSA system

Objective

To report on combined surgical and/or endovascular procedures for cerebrovascular disease in a hybrid operating room (OR).

Methods

Between October 2016 and June 2020, 1832 neurosurgical procedures were performed in a hybrid OR. Our institution’s hybrid OR consists of a multi-axis robotic C-arm monoplane digital subtraction angiography (DSA) system with an operating table, 3D-rotational DSA, cone-beam computed tomography (dyna CT), and real-time navigation software. Procedures were categorized into six categories according to purpose: (1) simple diagnosis and follow-up, (2) simple endovascular procedure, (3) combination of surgery and endovascular procedures, (4) rescue surgery after endovascular procedures, (5) frameless stereotactic procedure, and (6) other surgeries requiring C-arm.

Results

Of 1832 neurosurgical procedures in the hybrid OR, 1430 were simple diagnosis and follow-up cases, 330 simple endovascular procedures, 8 combination of surgery and endovascular procedures, 15 rescue after endovascular procedure, 40 frameless stereotactic procedures, and 9 other surgeries. Eight cases of combination of surgery and endovascular procedures, safely performed without wasting time on patient transfer, were performed in seven bypass end endovascular procedures and one case of bow-hunter syndrome in complex cerebrovascular disease. After embolization, craniotomy (or craniectomy) and intracerebral hemorrhage removal were performed in eight patients in-situ. Of the 40 frameless stereotactic procedure, 37 were extraventricular drainage before/after coil embolization in subarachnoid hemorrhage patients. They all mounted conduits in their planned locations.

Conclusions

A hybrid OR for combined endovascular and surgical procedures represents a safe and useful strategy for cerebrovascular disease. In hybrid ORs various neurosurgical procedures can be safely and conveniently performed. Hybrid OR will pioneer a new era in neurosurgical procedures.

Adverse intraoperative events during surgical repair of ruptured cerebral aneurysms: a systematic review

Compared with endovascular techniques, clipping of ruptured cerebral aneurysms has been shown to associate with increased morbidity in several studies. Despite this, clipping remains the preferred option for many aneurysms. The objective of this study is to describe the reported adverse events of open repair of ruptured cerebral aneurysms and their impact on patient outcome. The PubMed, Embase and Cochrane databases were searched between June 1999 and June 2019 to identify original studies of at least 100 patients undergoing surgical repair of ruptured cerebral aneurysms and in which adverse event rates were reported. Thirty-six studies reporting adverse events in a total of 12,410 operations for repair of ruptured cerebral aneurysms were included. Surgical adverse events were common with 36 event types reported including intraoperative rupture (median rate of 16.6%), arterial injury (median rate of 3.8%) and brain swelling (median rate 5.6%). Only 6 surgical events were statistically shown to associate with poor outcomes by any author and for intraoperative rupture (the most frequently analysed), there was an even split between authors finding a statistical association with poor outcome and those finding no association. Even with modern surgical techniques, the technical demands of surgical aneurysm repair continue to lead to a high rate of intraoperative adverse events. Despite this, it is not known which of these intraoperative events are the most important contributors to the poor outcomes often seen in these patients. More research directed towards identifying the events that most drive operative morbidity has the potential to improve outcomes for these patients.

Intraoperative 3-Dimensional Rotational Angiography in Cerebrovascular Surgery: A Case Series

OBJECTIVE

Intraoperative imaging is critical in cerebrovascular surgery to assess the technical success of the operation. This case series aimed to evaluate the safety and efficacy of 3-dimensional rotational angiogram (3D-RA) in addition to 2-dimensional intraoperative angiography (2D-IOA) during cerebrovascular surgery in the hybrid operating room.

METHODS

All consecutive patients who underwent open cerebrovascular surgery and intraoperative 2D-IOA with 3D-RA in a hybrid operating room at 2 academic centers between August 2018 and December 2019 were identified from a prospectively maintained institutional database. Medical charts and operative videos including intraoperative angiography were reviewed, and clinical and angiographic outcomes assessed.

RESULTS

A total of 40 cerebrovascular surgeries in 39 patients (mean age, 53 ± 13 years; 51% female) were carried out with the addition of 3D-RA to 2D-IOA in the hybrid operating room. After 3D-RA in addition to 2D-IOA, 1 (2.5%) surgical alteration occurred in an aneurysm clipping. Other procedures were not altered with the addition of 3D-RA to 2D-IOA. There were no complications from the addition of 3D-RA to 2D-IOA.

CONCLUSIONS

Using a combination of 3D-RA and 2D-IOA in the hybrid operating room may enhance the likelihood of achieving an optimal result when employing microsurgical cerebrovascular surgery and avoid unanticipated incomplete outcomes, complications, and returns to the operating room. Whereas the addition of 3D-RA elucidated residual aneurysm not otherwise visualized on the 2D-IOA, in other cerebrovascular procedures studied, there was no additional value of the 3D-RA over the 2D-IOA.

Radial Arterial Access for Thoracic Intraoperative Spinal Angiography in the Prone Position

BACKGROUND

Verification of complete occlusion or resection of neurovascular lesions is often performed using intraoperative angiography. Surgery for spinal vascular lesions such as arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs) is typically performed with the patient in the prone position, making intraoperative angiography difficult. No standardized protocol is available for intraoperative angiography during spinal surgery with the patient in the prone position. We have described our experience using radial artery access for intraoperative angiography in thoracic spinal neurovascular procedures performed with the patient in the prone position.

METHODS

We reviewed the data from all patients who had undergone surgical resection of spinal vascular lesions in the prone position with radial artery vascular access for intraoperative angiography. The patients were treated in a hybrid endovascular operating room.

RESULTS

A total of 4 patients were treated in the prone position using transradial artery access intraoperative angiography for confirmation of complete resection of the vascular lesions. Of the 4 patients, 2 had undergone surgery for a dural AVF, 1 for a pial AVF, and 1 for an AVM of the filum terminale. None of the patients had experienced any procedural complications.

CONCLUSION

Radial artery access for intraoperative angiography during spinal neurovascular procedures in which selective catheterization of a thoracic branch is necessary is feasible, safe, and practical.

Intraoperative Angiography for Arteriovenous Malformation Resection in the Prone and Lateral Positions, Using Upper Extremity Arterial Access

BACKGROUND

Intraoperative angiography is routinely utilized for aneurysms and arteriovenous malformations (AVMs) to verify complete occlusion and resection. Surgery for spinal and posterior fossa neurovascular lesions is usually performed in prone position. Intraoperative angiography in the prone position is challenging and there is no standardized protocol for this procedure.

OBJECTIVE

To describe our experience with intraoperative angiography in the prone and lateral positions, using upper extremity arterial access.

METHODS

We reviewed our experience with intraoperative angiography in the prone position between 2014 and 2015, where vascular access was obtained via the upper extremity arteries. Patients were treated in a hybrid endovascular operating room. High cervical and intracranial lesions were studied via brachial or radial access. All accesses were obtained using ultrasonographic guidance and a small caliber arterial sheath (4F).

RESULTS

Five patients were treated in the prone and lateral positions using brachial/radial artery access. Patients harbored cerebellar AVM, lateral medullary AVM, cervical arteriovenous fistula (AVF), tentorial dural AVF, and tentorial-incisural dural AVF. Patients were positioned prone (n = 2), semiprone (n = 2), and lateral (n = 1) for the surgery. Three patients were treated via right brachial artery access. Two patients were treated via radial arteries access. All patients tolerated the procedures without technical or clinical complications. Intraoperative angiography verified complete occlusion and resection in all cases prior to surgical closure.

CONCLUSIONS

Intraoperative angiography in the prone and lateral positions using upper extremity access is an important adjunct. Brachial or radial access can be obtained safely and provides comfortable and quick approaches.

Comparison of 3D intraoperative digital subtraction angiography and intraoperative indocyanine green video angiography during intracranial aneurysm surgery

OBJECTIVE

During the last decade, improvements in real-time, high-resolution imaging of surgically exposed cerebral vasculature have been realized with the successful introduction of intraoperative indocyanine green video angiography (ICGVA) and technical advances in intraoperative digital subtraction angiography (DSA). With the availability of 3D intraoperative DSA (3D-iDSA) in hybrid operating rooms, the present study offers a contemporary comparison for rates of accuracy and discordance.

METHODS

In this retrospective study of prospectively collected data, 140 consecutive patients underwent microsurgical treatment of intracranial aneurysms (IAs) in a hybrid operating room. Variables analyzed included patient demographics, aneurysm-specific characteristics, intraoperative ICGVA and 3D-iDSA findings, and the need for intraoperative clip readjustment. The authors defined the discordance rate of the two modalities as a false-negative finding that necessitated clip repositioning after 3D-iDSA.

RESULTS

In 120 patients, ICGVA and 3D-iDSA were used to evaluate 134 IA obliterations. Of 215 clips used, 29 (14%) were repositioned intraoperatively, improving the surgical result in all 29 patients (24%). Repositioning was prompted by visual inspection and microvascular Doppler ultrasonography in 8 (28%), ICGVA in 13 (45%), and 3D-iDSA in 7 (24%) patients. Clip repositioning was needed in 7 patients (6%) based on 3D-iDSA, yielding an ICGVA accuracy rate of 94%. Five (71%) of the ICGVA-3D-iDSA discordances that prompted clip repositioning occurred at the anterior communicating artery complex.

CONCLUSIONS

A combination of vascular monitoring techniques most often achieved correct intraoperative interpretation of complete IA occlusion and parent artery integrity. Compared with 3D-iDSA imaging, ICGVA demonstrated high accuracy. Despite the relatively low discordance rate, iDSA was confirmed to be the gold standard. Improved imaging quality, including 3D-iDSA, supports its routine use in IA surgery, obviating the need for postoperative DSA.

A hybrid operating room for combined surgical and endovascular procedures for cerebrovascular diseases: a clinical experience at a single centre

Purpose: To describe our experiences with a fully equipped high-end digital subtraction angiography (DSA) system within a hybrid operating room (OR). Material and methods: A single-plane DSA system with 3-dimensional rotational angiography (3DRA), cone-beam computed tomography, and real-time navigation software was used in our hybrid OR. Between April 2014 and January 2018, 191 sessions of neurovascular procedures were performed in our hybrid OR. After the retrospective review of all cases, the procedures were categorised into five subcategorical procedures according to the dominance of surgical and/or endovascular procedures: intraoperative angiographic evaluation, combined endovascular and surgical procedure, complementary rescue procedure during intervention and surgery, surgical approach for interventional procedure, and frameless stereotaxic operation. Results: Intraoperative angiography revealed unsatisfactory clipping of intracranial aneurysms in 6 (13.6%) patients and remnant AVMs in 1 (16.7%) patient, which were determined as complete surgical outcome via indocyanine green videoangiography. Four cases of blood blister aneurysms and a ruptured posterior inferior cerebellar artery aneurysm were treated using bypass surgery and endovascular trapping. Eight cases of ruptured aneurysm with intracranial haemorrhage (ICH) were treated by partial embolisation and surgical clipping. Two (5.4%) of the 37 cases of pre-mature rupture during clipping were secured by endovascular coil embolisation. In 1 (0.8%) complicated case of 103 intra-arterial (IA) thrombectomy procedures, emergency surgical embolectomy with bypass surgery was performed. Direct puncture of the common carotid artery or vertebral artery was performed to achieve interventional access to treat aneurysm or recanalise vessel occlusions in 7 cases. In 27 cases of ICH, frameless stereotaxic haematoma aspiration was performed using XperGuide® system. All procedures were performed in single sessions without any procedural complications. Conclusion: Hybrid OR with a fully equipped DSA system could provide safe and precise treatment for neurovascular diseases. Hybrid procedures for neurovascular diseases in hybrid OR are a promising new trend.

Transfemoral Approach for Intraoperative Angiography in the Prone or Three-quarter Prone Position : A Revisited Protocol for Intracranial Arteriovenous Malformation and Fistula Surgery

PURPOSE

Among the different arterial accesses, the femoral access is the main approach for intraoperative angiography (IOA) performed in a prone position. Without a standardized protocol, however, the application of prone IOAs in intracranial arteriovenous malformation (AVM) or arteriovenous fistula (AVF) surgery remains limited by its procedural complexity. This study describes the detailed protocol for prone IOA through a transfemoral approach and highlights several refinements in preparing this procedure.

METHODS

This study retrospectively reviewed the intracranial or high cervical AVM/AVF surgical cases in which both resection and IOA were performed in the prone or three-quarter prone position. Extended femoral sheath approaches and radiolucent head clamps were used in all cases. An aneurysm clip, serving as a localization landmark in IOA, was routinely placed within the surgical field. The IOA imaging, clinical impact of IOA, and complications related to the procedure were recorded.

RESULTS

A total of six AVM and three AVF cases, operated on in the prone (n = 7) or three-quarter prone (n = 2) positions, were included. Multiple vessel injections were required in 66.7% of cases, and IOA was successfully performed in every intended vessel. All IOA images were adequate for interpretation, except for two cases in which the non-radiolucent component of the head clamp obscured the region of interest in the lateral views. Incomplete occlusion was identified in two patients, and the aneurysm clip provided precise guidance in localizing the residual nidus. Final IOA confirmed complete lesion removal in all cases, and there were no IOA-related complications.

CONCLUSION

Three key steps in setting-up a prone IOA procedure for intracranial AVM/AVF surgery are proposed: (1) utilize an extended femoral sheath approach, (2) establish a localization landmark with an aneurysm clip and (3) avoid possible image interference from the non-radiolucent component of the head clamp.

Combined Microsurgery and Endovascular Intervention in One-Stop for Treatment of Cerebral Arteriovenous Malformation: The Efficacy of a Hybrid Operation

To investigate the efficacy of a hybrid operation combining microsurgical resection and endovascular interventions in a one-stop treatment of cerebral arteriovenous malformation (AVM). Patients were divided into two groups: patients who received a hybrid operation, and patients receiving a non-hybrid operation. The hybrid operation group consisted of microsurgical resection with intraoperative angiography, or endovascular embolization. The non-hybrid operation group consisted of microsurgical resection or endovascular embolization, or microsurgery combined with embolization in multiple steps. Comprehensive clinical data was collected for all patients, including preoperative Glasgow Coma Scale score, Spetzler-Martin grade, rehemorrhagia, image follow-up, and 6-month outcomes of the modified Rankin Scale (mRS) score. This study included 22 cases in the hybrid operation group. The remnants were noted on intraoperative angiography in the four patients that were resected within the same session. The non-hybrid group consisted of 52 patients. There were no statistical differences between the two groups with GCS and Spetzler-Martin grade score. The mortality rate in the hybrid operation group was 4.5%, which was lower than the 7.6% obtained in the control group. No patients experienced post-operation rehemorrhagia in the hybrid operation group, but five cases occurred in the control group. The follow-up radiological cure rates were 100% in the hybrid group and 65.9% in the control group. The rate of good outcome was 81.8% in the hybrid operation group and 69.2% in the control group, although there was no significant difference. The hybrid operation is a safe and efficacious strategy for treating cerebral AVMs.

Safety and Feasibility Assessment of the O-Arm as an Intraoperative Angiography Device in Aneurysm Surgery

OBJECTIVE

To describe the technique and initial experience of using a rotational 3-dimensional (3D) fluoroscopy system (O-arm; Medtronic) as intraoperative angiography (IA) in the surgery of cerebral aneurysms.

METHODS

The 3D IA with O-arm (IAWOA) was performed in a consecutive cohort of patients with unruptured intracranial aneurysms. Conventional microsurgical clipping was performed with the assistance of indocyanine green videoangiography. Then the O-arm chassis was brought in, the ipsilateral internal carotid artery was catheterized, and contrasted images were acquired. Resulting datasets were exported in Digital Imaging and Communications in Medicine and processed using the Osirix software in an accessory computer. The 3D image reconstruction was evaluated intraoperatively to confirm aneurysm occlusion and parent vessel patency. Afterward, agreement among IAWOA, indocyanine green videoangiography, and standard postoperative angiography was analyzed.

RESULTS

The initial pilot study was performed in 6 patients with 7 unruptured aneurysms. The aneurysm occlusion rate was 100%. The concordance of the IAWOA and the standard postoperative angiography was complete, both in terms of occlusion and parent vessel patency. No complications derived from the IAWOA were observed except in 1 patient, who presented a retroperitoneal hematoma without clinical consequences.

CONCLUSIONS

The 3D rotational fluoroscopy (O-arm) device could be safely and effectively used as an IA system in selected patients. To the best of our knowledge, this is the first study reporting its use as an IA device. This technique seems to offer excellent image quality that could be compared with that of the gold standard 3D digital subtraction angiography but with a lower cost and versatility of use for other subspecialties.

Intravenous 3-Dimensional Digital Subtraction Angiography During Surgical Treatment of Intracranial Aneurysm

BACKGROUND

Although intraarterial 3-dimensional digital subtraction angiography (ia-3DDSA) using an angiographic C-arm system is still the gold standard for postoperative confirmation of surgical clipping of intracranial aneurysms, ia-3DDSA requires catheterization and intraarterial injection of contrast medium, which adds risks to the surgical procedure and takes time. We propose a less invasive acquisition of 3D digital subtraction angiography with intravenous injection (iv-3DDSA) in the hybrid operating room to confirm the results of surgical clipping immediately after surgery.

CASE DESCRIPTION

A 56-year-old woman was diagnosed with an incidental wide-necked aneurysm located at the distal anterior cerebral artery. We performed surgical clipping. During the surgery, indocyanine green video angiography and Doppler ultrasonography were used for confirmation, and after the surgery iv-3DDSA and ia-3DDSA were performed with the angiography C-arm system in the hybrid operating room while the patient was still under anesthesia. We could confirm that there was no neck remnant left and that the parent vessels were patent on both iv-3DDSA and ia-3DDSA images. The image quality of iv-3DDSA was sufficient for all treatment evaluations and offered the additional benefits of visualizing the whole angioarchitecture including the contralateral side, being less invasive, and requiring only a few minutes until the availability of images.

CONCLUSIONS

Iv-3DDSA can be useful for postsurgical confirmation of clipping of aneurysms in the hybrid operating room.

Intraoperative angiography via the popliteal artery: a useful technique for patients in the prone position

OBJECTIVE Intraoperative angiography can be a valuable tool in the surgical management of vascular disorders in the CNS. This is typically accomplished via femoral artery puncture; however, this can be technically difficult in patients in the prone position. The authors describe the feasibility of intraoperative angiography via the popliteal artery in the prone patient. METHODS Three patients underwent intraoperative spinal angiography in the prone position via vascular access through the popliteal artery. Standard angiography techniques were used, along with ultrasound and a micropuncture needle for initial vascular access. Two patients underwent intraoperative angiography to confirm the obliteration of dural arteriovenous fistulas. The third patient required unexpected intraoperative angiography when a tumor was concerning for a vascular malformation in the cervical spine. RESULTS All 3 patients tolerated the procedure without complication. The popliteal artery was easily accessed without any adaptation to typical patient positioning for these prone-position cases. This proved particularly beneficial when angiography was not part of the preoperative plan. CONCLUSIONS Intraoperative angiography via the popliteal artery is feasible and well tolerated. It presents significant benefit when obtaining imaging studies in patients in a prone position, with the added benefit of easy access, familiar anatomy, and low concern for catheter thrombosis or kinking.

Combined Surgical and Endovascular Treatment of a Complex Posterior Communicating Artery Aneurysm at One-Stage in a Hybrid Operating Room

BACKGROUND

Although clipping and coiling of intracranial aneurysms are effective treatment options, they each have limitations. With the advent of the hybrid operating room, combined clipping and coiling for complex aneurysms in one stage becomes feasible. We report a successful case of a left posterior communicating artery aneurysm where combined clipping and endovascular treatment were applied.

CASE DESCRIPTION

A 57-year-old man had been complaining of severe headache for 10 days. The computed tomography scan from a previous hospital revealed a parasellar lesion, and the computed tomography angiography in our hospital showed a 16-mm posterior communicating artery aneurysm. Clipping of the aneurysm was scheduled in our hybrid operating room, which enabled intervention of intraoperative digital subtraction angiography (DSA). However, once the aneurysm was clipped, intraoperative DSA revealed that the aneurysm was remnant. We readjusted the clip and reran DSA, but the residual neck was still present. In an effort to preserve the parent artery and perforators, we decided to perform endovascular treatment. Coiling was achieved, followed by angiography, indicating that the aneurysm was almost eliminated. Overall, the patient underwent 4 angiographic explorations during surgery.

CONCLUSIONS

Combined open surgical and endovascular approaches to treat complex cerebral aneurysms in an hybrid operating room could offer an alternative when the aneurysms appear unclipped or remnant intraoperatively. In our experience, simultaneous clipping and coiling is a safe and effective procedure for efficient treatment of aneurysms.

Treatment of giant cavernous aneurysm in an elderly patient via extracranial-intracranial saphenous vein bypass graft in a hybrid operating room: A case report

RATIONALE

Extracranial-intracranial saphenous vein bypass (EC-IC SVB) remains indispensable for treating giant cavernous aneurysms. We report an unusual case of a giant cavernous aneurysm in an elderly patient treated with EC-IC SVB in a hybrid operating room. Immediately following proximal ligation of the internal carotid artery (ICA), she suffered an acute intraoperative encephalocele.

PATIENT CONCERNS

A 71-year-old woman had suffered from severe headache and double vision for 4 months.

DIAGNOSES

The woman was diagnosed with a right giant cavernous aneurysm.

INTERVENTIONS

She was treated with an EC-IC SVB with therapeutic ICA occlusion in the first biplane hybrid operating room in China. Just after proximal ligation of the ICA, she developed an acute encephalocele, and immediately underwent decompressive craniectomy. During the surgery she underwent 3 angiographic explorations.

OUTCOMES

After surgery, the aneurysm disappeared, and the graft was patent. Postoperative computed tomography and computed tomography angiography indicated a cranial defect and graft patency.

LESSONS

Although a hybrid operating room could improve the patency of grafts, the timing of ICA ligation for giant cavernous aneurysm via EC-IC bypass deserves further discussion. Second-stage ICA occlusion could offer an alternative for elderly patients requiring such treatment. In addition, cranial flap removal could prevent further neurologic deficits in a case of acute intraoperative encephalocele.

A Critical Analysis of the Utility of Intraoperative Angiography

OBJECTIVE

Intraoperative digital subtraction angiography (ioDSA) is touted as the gold standard imaging evaluation for aneurysm clip constructs. Candid evaluations of its limitations are sparse.

METHODS

A prospectively collected hospital billing database was queried to identify craniotomies for aneurysm clipping from January 2010 to December 2013. We evaluated the rate of occult residual and parent vessel stenosis determined on follow-up angiography for patients undergoing ioDSA and those not undergoing ioDSA. Comparisons were performed via Fisher exact test, with P < 0.05 considered statistically significant.

RESULTS

From our database search, we found 187 patients who underwent ioDSA after aneurysm clipping and an additional 91 patients who did not. Results from ioDSA influenced operative management in 17% of cases. Sixty-four patients with 70 treated aneurysms undergoing ioDSA had postoperative angiography; 7 occult residuals were discovered, yielding a 10% false-negative rate, with 10% of aneurysms showing residual. Occult residuals at the middle cerebral artery bifurcation represented most discovered residuals (6/7). Thirty-two patients with 37 treated aneurysms did not undergo ioDSA and had angiographic follow-up; 24% of patients were found to have residual aneurysms (P = 0.08 compared with patients undergoing ioDSA). Residuals at the anterior communicating artery (ACoA) represented 56% of all residuals, whereas the ACoA represented only 18% of aneurysms clipped. The rate of residuals was significantly higher than that for patients with clipped ACoA aneurysms undergoing ioDSA (P = 0.008).

CONCLUSIONS

ioDSA influenced management in nearly one fifth of cases. It can be particularly beneficial in detecting residuals for ACoA aneurysms; its benefit was less apparent for middle cerebral artery aneurysms.

Application of Multimodal Navigation together with Fluorescein Angiography in Microsurgical Treatment of Cerebral Arteriovenous Malformations

This study aimed to explore the clinical applications of multimodal navigation combined with indocyanine green (ICG) fluorescein angiography in microsurgical treatment of cerebral arteriovenous malformations (AVMs). We retrospectively collected 52 patients with AVMs. Assisted by anatomic image, we reestablished three-dimensional structure using preoperative functional magnetic resonance imaging (fMRI) and Diffusion tensor imaging (DTI). The operation for lesion resection was finished under the assistance of neuro-navigation. ICG fluorescein angiography was performed for 16 of the study subjects, meanwhile, FLOW800 was used to rebuild blood vessel color visual image. Brain angiography was performed 1 week after the operation to check residual malformations. The patients’ status was estimated by Modified Rankin Scale score. Of the AVMs, 92.3% (48/52) were totally removed, without severe side events. Among the patients, fluorescein angiography was carried out up to 58 times for 16 cases. All of these 16 cases were confirmed with malformations and 14 of them had draining vein. The total resection rate of these 16 cases reached 100%, and the occurrence rate of postoperative complications was not significantly increased. During the operation of lesion resection, the application of multimodal navigation could effectively protect functional cortex and conduction pathway.

Intraoperative Imaging for Vascular Lesions

Neurovascular surgery is a broad and challenging, yet exciting field within neurologic surgery. The neurovascular surgeon must be meticulous; because the brain and spinal cord are unforgiving to ischemic insults. Along with the pressures of this demanding subspecialty comes the potential to help patients recover from potentially devastating pathology to go on and lead normal, healthy lives. Several intraoperative imaging modalities are available to help maximize treatment success while reducing risk. This article reviews each of these modalities, including digital subtraction angiography, fluorescence angiography, Doppler ultrasonography, laser Doppler, laser speckle contrast imaging, neuronavigation, and neuroendoscopy.

Advanced intraoperative imaging

There are several unique features of the concept of advanced intraoperative imaging modalities with CT (computed tomography), MRI (magnet resonance imaging) and DSA (digital substraction angiography) inaugurated in one operating tract. For the first time, there is the opportunity to switch from postoperative to intraoperative imaging – when the surgeon can not only check the result of surgery but improve it – but in general, that is, for all specialties, at least theoretically. Intraoperative imaging is a broad term with many technologies already in routine use today, such as image intensifier, ultrasound, fluorescence technologies, and soon. Using intra-operative CT, MRI, and DSA is not indisputable. Does the benefit justify such immense costs, both in building and in maintenance? To evaluate the clinical benefit and possible drawbacks of these technologies and if there's a substantial benefit for the patients. Also, this is a review of literature to evaluate the evidence and clinical impact of advanced intraoperative imaging in neurosurgery. There is one prospective randomized trial showing that intraoperative MRI increases the extent of resection. In spine surgery, there are several randomized trials showing that pedicle screws are inserted more accurately when image guidance is used. However, there is no RCT comparing navigation with intraoperative CT-updated navigation. Several prospective studies are showing that intraoperative DSA is able to identify vascular remnants or vessel occlusions in case of aneurysm-, arteriovenous malformation-and arteriovenous fistula-surgery. A fair comparison of the benefit of these new technologies must take into consideration that other methods of intraoperative imaging or image guidance already exist. Hence, there are some patients in whom the use of the more advanced technologies makes a personal, individual difference that may affect quality of life and survival. We have to differentiate between (1) the best diagnostic procedure and (2) the term “standard of care.” Advanced intraoperative imaging is a gold standard in terms of imaging but not a standard of care.

PulseRider-assisted treatment of wide-necked intracranial bifurcation aneurysms: safety and feasibility study

OBJECTIVE The goal of this study was to assess the safety and feasibility of PulseRider, a novel endovascular stent, in the treatment of intracranial bifurcation aneurysms with wide necks. The authors present the initial results of the first 10 cases in which the PulseRider device was used. METHODS Patients whose aneurysms were intended to be treated with the PulseRider device at 2 institutions in the United Kingdom were identified prospectively. Patient demographics, procedural details, immediate neurological and clinical status, and immediate angiographic outcomes and 6-month clinical and imaging follow-up were recorded prospectively. RESULTS At the end of the procedure, all 10 patients showed complete aneurysm occlusion (Raymond Class 1). There were no significant intraprocedural complications except for an occurrence of thromboembolism without clinical sequelae. There was no occurrence of aneurysm rupture or vessel dissection. At 6-month follow-up, 7 and 3 patients had modified Rankin Scale scores of 0 and 1, respectively. All 10 patients had stable aneurysm occlusion (Raymond Class 1) and daughter vessel intraluminal patency on 6-month follow-up catheter angiography. CONCLUSIONS The authors' early experience with the PulseRider device demonstrates that it is a safe and effective adjunct in the treatment of bifurcation aneurysms with wide necks arising at the middle cerebral artery bifurcation, anterior cerebral artery, basilar apex, and carotid terminus. It works by providing a scaffold at the neck of the bifurcation aneurysm, enabling neck remodeling and coil support while maintaining parent vessel intraluminal patency. Early clinical and radiological follow-up showed good functional outcome and stable occlusion rates, respectively. Further data are needed to assess medium- and long-term outcomes with PulseRider.

Novel imaging approaches to cerebrovascular disease

Imaging techniques available to the physician treating neurovascular disease have substantially grown over the past several decades. New techniques as well as advances in imaging modalities continuously develop and provide an extensive array of modalities to diagnose, characterize, and understand neurovascular pathology. Modern noninvasive neurovascular imaging is generally based on computed tomography (CT), magnetic resonance (MR) imaging, or nuclear imaging and includes CT angiography, CT perfusion, xenon-enhanced CT, single-photon emission CT, positron emission tomography, magnetic resonance angiography, MR perfusion, functional magnetic resonance imaging with global and regional blood oxygen level dependent imaging, and magnetic resonance angiography with the use of the noninvasive optional vessel analysis software (River Forest, Ill). In addition to a brief overview of the technique, this review article discusses the clinical indications, advantages, and disadvantages of each of those modalities.

Comparison of Intraoperative Indocyanine Green Angiography and Digital Subtraction Angiography for Clipping of Intracranial Aneurysms

BACKGROUND

Residual aneurysm after microsurgical clipping carries a risk of aneurysm growth and rupture. Digital subtraction angiography (DSA) remains the standard to determine the adequacy of clipping. Intraoperative indocyanine green (ICG) angiography is increasingly utilized to confirm optimal clip positioning across the neck and to evaluate the adjacent vasculature.

OBJECTIVE

We evaluated the correlation between ICG and DSA in clipped intracranial aneurysms.

METHODS

A retrospective study of patients who underwent craniotomy and microsurgical clipping of intracranial aneurysms with ICG for 2 years. Patient characteristics, presentation details, operative reports, and pre- and postclipping angiographic images were reviewed to determine the adequacy of the clipping.

RESULTS

Forty-seven patients underwent clipping with ICG and postoperative DSA: 57 aneurysms were clipped; 23 patients (48.9%) presented with subarachnoid hemorrhage. Nine aneurysms demonstrated a residual on DSA not identified on ICG (residual sizes ranged from 0.5 to 4.3 mm; average size: 1.8 mm). Postoperative DSA demonstrated no branch occlusions.

CONCLUSION

Intraoperative ICG is useful in the clipping of intracranial aneurysms to ensure a gross patency of branch vessels; however, the presence of residual aneurysms and subtle changes in flow in branch vessels is best seen by DSA. This has important clinical implications with regard to follow-up imaging and surgical/endovascular management.

Role of intraoperative indocyanine green video-angiography to identify small, posterior fossa arteriovenous malformations mimicking cavernous angiomas. Technical report and review of the literature on common features of these cerebral vascular malformations

OBJECTIVE

To illustrate the usefulness of intraoperative indocyanine green videoangiography (ICG-VA) to identify the nidus and feeders of a small cerebellar AVM resembling a cavernous hemangioma. To review the unique features regarding the overlay between these two vascular malformations and to highlight the importance to identify with ICG-VA, and treat accordingly, the arterial and venous vessels of the AVM.

METHODS

A 36-year old man presented with bilateral cerebellar hemorrhage. MRI was equivocal in showing an underlying vascular malformation but angiography demonstrated a small, Spetzler-Martin grade I AVM. Surgical resection of the AVM with the aid of intraoperative ICG-VA was performed. After hematoma evacuation, pre-resection ICG-VA did not reveal tortuous arterial and venous vessels in keeping with a typical AVM but rather an unusual blackberry-like image resembling a cavernous hemangioma, with tiny surrounding vessels. Such intraoperative appearance, which could also be the consequence of a "leakage" of fluorescent dye from the nidal pathological vessels, with absent blood-brain barrier, into the surrounding parenchymal pathological capillary network, is important to be recognized as an unusual AVM appearance.

RESULTS

Post-resection ICG-VA confirmed the AVM removal, as also shown by postoperative and 3-month follow-up DSAs.

CONCLUSIONS

Despite technical limitations associated with ICG-VA in post-hemorrhage AVMs, this case together with the intraoperative video, demonstrates the useful role of ICG-VA in identifying small AVMs with peculiar features.

Guidelines for the Management of Patients With Unruptured Intracranial Aneurysms: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

PURPOSE

The aim of this updated statement is to provide comprehensive and evidence-based recommendations for management of patients with unruptured intracranial aneurysms.

METHODS

Writing group members used systematic literature reviews from January 1977 up to June 2014. They also reviewed contemporary published evidence-based guidelines, personal files, and published expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulated recommendations using standard American Heart Association criteria. The guideline underwent extensive peer review, including review by the Stroke Council Leadership and Stroke Scientific Statement Oversight Committees, before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

Evidence-based guidelines are presented for the care of patients presenting with unruptured intracranial aneurysms. The guidelines address presentation, natural history, epidemiology, risk factors, screening, diagnosis, imaging and outcomes from surgical and endovascular treatment.

Intraoperative Angiography Using Portable Fluoroscopy Unit in the Treatment of Vascular Malformation

Intraoperative angiography (IOA) is employed for the treatment of the complicated cases in neurological surgery. The IOA is usually performed with OEC portable digital subtraction angiography (DSA) unit. We are performing IOA with portable fluoroscopy unit with simple DSA function and report its usefulness on neurosurgical treatment. IOA or hybrid treatment with mobile fluoroscopy system was performed for 9 cases [cerebral arteriovenous malformation (AVM), 3; cranial dural arteriovenous fistula (AVF), 2; and spinal AVM/AVF, 4]. Thus, ex vivo analysis was performed comparing image quality of portable fluoroscopy unit and conventional DSA system. Although the resolution of portable fluoroscopy unit is not so high compared to conventional DSA system, the existence of the vascular lesions such as cerebral aneurysm, cerebral AVM, and spinal dural AVF were detected. The operation of portable fluoroscopy unit was simple and no special assistance was required. The complication related to the catheterization or IOA did not occur. IOA with portable fluoroscopy unit was useful for the identification of vascular lesion and has advantage on the cost benefit.

Initial experience with the PulseRider for the treatment of bifurcation aneurysms: report of first three cases in the USA

Introduction

The PulseRider is a novel device intended for use in the treatment of aneurysms arising at bifurcations. We present the initial results of the first three cases in the USA employing the PulseRider device.

Methods

Aneurysms intended to be treated with the PulseRider device at a single institution were identified prospectively. Aneurysms arising at either the carotid terminus or basilar apex that were relatively broad-necked were considered candidates for treatment with the novel device.

Results

Patients were pretreated with dual antiplatelet therapy. All cases were performed under general endotracheal anesthesia. An appropriately sized PulseRider device was deployed across the neck of the aneurysm. A microcatheter was then navigated over a 0.014 inch microwire through the device into the aneurysm. Complete occlusion of the aneurysm was achieved in all cases without intraprocedural complications.

Conclusions

We have found in our early experience with the Pulse Rider device that its use is safe and effective as an adjunct in the treatment of bifurcation aneurysms arising at the basilar apex or carotid terminus. As such, it represents a useful addition to the armamentarium of the neuroendovascular specialist.

Comparing routine versus selective use of intraoperative cerebral angiography in aneurysm surgery: a prospective study

INTRODUCTION

While the use of intraoperative angiography (IA) has been shown to be a useful adjunct in aneurysm surgery, its routine use remains controversial.

OBJECTIVE

We wished to determine if IA is required in all patients undergoing aneurysm surgery (ie, routine IA) or if intraoperative assessment can reliably predict the need for IA (ie, select IA).

METHODS

We prospectively evaluated all patients undergoing craniotomy for aneurysm clipping. In these patients, the treating surgeons were asked to record whether they felt IA was required at two time points: (1) prior to surgery and (2) immediately after clip application but before IA. All patients underwent IA as per the institutional protocol. IA results and the need for post-IA clip adjustments were recorded.

RESULTS

Of the 200 patients enrolled, 197 were included for analysis. IA was deemed necessary on preoperative assessment in 144 cases (73%) and on post-clip assessment in 116 cases (59%). Post-clip IA demonstrated 47 (24%) positive findings and post-IA clip adjustments were made in 19 of 198 cases (10%). On preoperative assessment, there were four cases where IA was deemed unnecessary, yet post-IA clip adjustment was required, resulting in a sensitivity of 79% and false negative rate of 8%. Regarding post-clip assessment, there were five cases where IA was thought to be unnecessary and clip adjustment was required, resulting in a sensitivity of 73% and false negative rate of 6%.

CONCLUSIONS

The accuracy of a strategy of select IA was not improved by assessing the need for IA immediately after aneurysm clipping versus prior to surgery onset. This suggests that intraoperative assessment regarding the adequacy of aneurysm clip application should be viewed with caution.

Aneurysmal subarachnoid haemorrhage from a neuroimaging perspective

Neuroimaging is a key element in the management of patients suffering from subarachnoid haemorrhage (SAH). In this article, we review the current literature to provide a summary of the existing neuroimaging methods available in clinical practice. Noncontrast computed tomography is highly sensitive in detecting subarachnoid blood, especially within 6 hours of haemorrhage. However, lumbar puncture should follow a negative noncontrast computed tomography scan in patients with symptoms suspicious of SAH. Computed tomography angiography is slowly replacing digital subtraction angiography as the first-line technique for the diagnosis and treatment planning of cerebral aneurysms, but digital subtraction angiography is still required in patients with diffuse SAH and negative initial computed tomography angiography. Delayed cerebral ischaemia is a common and serious complication after SAH. The modern concept of delayed cerebral ischaemia monitoring is shifting from modalities that measure vessel diameter to techniques focusing on brain perfusion. Lastly, evolving modalities applied to assess cerebral physiological, functional and cognitive sequelae after SAH, such as functional magnetic resonance imaging or positron emission tomography, are discussed. These new techniques may have the advantage over structural modalities due to their ability to assess brain physiology and function in real time. However, their use remains mainly experimental and the literature supporting their practice is still scarce.

Intraoperative angiography does not lead to increased rates of surgical site infections

BACKGROUND

Intraoperative angiography (IOA) is essential in evaluating residual aneurysm following clip ligation, but it does lead to an additional procedure which increases the duration of the procedure as well as increasing room traffic. We examined whether IOA during microsurgery is a risk factor for developing cranial surgical site infection.

MATERIALS AND METHODS

A retrospective cohort study was performed of all patients undergoing craniotomy for aneurysm treatment between 2005 and 2012 at the University of Michigan. IOA was used at the surgeons' discretion. The primary outcome of interest was occurrence of a surgical site infection and the secondary outcome of interest was clip repositioning following IOA. Variables including IOA were tested for their independent association with the occurrence of a surgical site infection.

RESULTS

During the study period 676 intracranial aneurysms were treated by craniotomy; IOA was used in 104 of these cases. There were a total of 20 surgical site infections, 2 in the IOA group (1.9%) and 18 in the non-IOA group (3.1%), indicating that IOA was not a statistically significant variable for infection (p=0.50). No additional single variable measured could be shown to have a statistically significant increase in infection, and there were no direct complications related to the use of IOA (stroke, dissection, perforation).

CONCLUSIONS

IOA does not increase the risk of developing a surgical site infection. It can be conducted without exposing patients to an undue risk of infection.

Microsurgical clipping of large and giant cerebral aneurysms: a single-center contemporary experience

Several treatment strategies are available to manage large and giant cerebral aneurysms, including surgical, endovascular and combined approaches. We present our experience with microsurgical clipping of large and giant aneurysms. A total of 138 patients with 139 aneurysms of which 128 were large (≥10mm) and 11 were giant (≥25mm) were treated at our institution between 2004 and 2011. Data were collected from a prospectively maintained neurovascular database. Of 138 patients, 53 (38.4%) patients presented with subarachnoid hemorrhage (SAH). Peri-operative complications occurred in 16.7% of patients causing permanent morbidity in 4.4% and death in 0.7%. Complete occlusion, as evident on intra-operative angiography, was achieved in all clipped aneurysms (100%). Long-term follow-up angiography showed no recurrence (mean follow-up time, 43.9 months; range: 1-72 months). Favorable outcomes at discharge (Glasgow Outcome Scale score 4 or 5) were noted in 64.1% of SAH patients and 93% of non-SAH patients. Favorable outcomes at follow-up (mean follow up time, 42.5 months) were seen in 96% of patients. In our experience, microsurgical clipping of large and giant aneurysms carries low rates of morbidity and mortality with high rates of favorable outcomes. The excellent durability of surgical treatment stands in stark contrast with the high recurrence rates observed with coiling for this subset of aneurysms. These data suggest that microsurgical clipping continues to be a viable option that can be offered for patients with large and giant aneurysms.

Safety, efficacy, and cost of intraoperative indocyanine green angiography compared to intraoperative catheter angiography in cerebral aneurysm surgery

Intraoperative angiography in cerebrovascular neurosurgery can drive the repositioning or addition of aneurysm clips. Our institution has switched from a strategy of intraoperative digital subtraction angiography (DSA) universally, to a strategy of indocyanine green (ICG) videoangiography with DSA on an as-needed basis. We retrospectively evaluated whether the rates of perioperative stroke, unexpected postoperative aneurysm residual, or parent vessel stenosis differed in 100 patients from each era (2002, "DSA era"; 2007, "ICG era"). The clip repositioning rate for neck residual or parent vessel stenosis did not differ significantly between the two eras. There were no differences in the rate of perioperative stroke or rate of false-negative studies. The per-patient cost of intraoperative imaging within the DSA era was significantly higher than in the ICG era. The replacement of routine intraoperative DSA with ICG videoangiography and selective intraoperative DSA in cerebrovascular aneurysm surgery is safe and effective.

Treatment of complex neurovascular lesions: an interdisciplinary angio suite approach

OBJECTIVE

The objective of this study was to analyse our initial experience using an interdisciplinary angio suite approach to neurosurgical treatment of complex neurovascular lesions and expound technical feasibility and possible applications.

SUBJECTS

Six out of 451 patients with cranial or spinal neurovascular lesions were surgically treated in the angio suite (biplane angiographic system) during a 28-month observation period. Clinical baseline data, radiological and intraoperative findings as well as clinical and radiological outcome were assessed.

RESULTS

A ventral spinal perimedullary arteriovenous malformation, a ventral spinal perimedullary fistula, two diffuse frontal dural arteriovenous fistulas, a multifocal temporal arteriovenous malformation and a partially embolized fronto-temporo-basal dural arteriovenous fistula were successfully treated with angiographically confirmed complete occlusion and unimpaired neurological condition of the patients at the 12-month follow up.

CONCLUSION

This study demonstrates the feasibility of this approach and points out possible indications, namely ventrally located spinal lesions and diffuse, deep seated cranial lesions.