Combined Endovascular and Microsurgical Treatment of Arteriovenous Malformations in the Hybrid Operating Room

The difference of functional MR imaging in evaluating outcome of patients with diffuse and compact brain arteriovenous malformation

Microsurgical resection is an effective method to treat brain arteriovenous malformations (BAVMs). Functional magnetic resonance imaging (fMRI) can evaluate the spatial relationship of nidus and eloquent. Diffuse BAVMs are related to poor outcomes postoperatively. The role of fMRI in evaluating outcomes in patients with different nidus types remains unclear. BAVM patients received microsurgical resection were included from a prospective, multicenter cohort study. All patients underwent fMRI evaluation preoperatively and were regularly followed up postoperatively. Diffuse BAVM is radiologically identified as nidus containing normal brain tissue interspersing between malformed vessels. Lesion-to-eloquent distance (LED) was calculated based on the relationship between nidus and eloquent. The primary outcome was 180-day unfavorable neurological status postoperatively. The risk of primary outcome was investigated within different BAVM nidus types. The LED's performance to predict poor outcome was evaluated using area under curve (AUC). 346 BAVM patients were included in this study. 93 (26.9%) patients were found to have a 180-day unfavorable outcome. Multivariate logistic analysis demonstrated LED (odd ratio [OR], 0.44; 0.34-0.57; P < 0.001) and mRS at admission (OR, 2.59; 1.90-3.54; P < 0.001) as factors of unfavorable outcome. Subgroup analysis showed LED and mRS at admission as factors of unfavorable outcome for patients with compact BAVMs (all P < 0.05), but not for patients with diffuse BAVMs. Subsequent analysis showed that LED performed poorly to predict the unfavorable outcome for patients with diffuse BAVMs, compared with patients with compact BAVMs (AUC as 0.69 vs. 0.86, P < 0.05). A larger cutoff value of LED to unfavorable outcome was found in patients with diffuse BAVMs (15 mm) compared with patients with compact BAVMs (4.7 mm). Usage of LED to evaluate postoperative outcome of patients with diffuse BAVMs differs from its use in patients with compact BAVMs. Specific assessment strategy considering BAVM nidus types could help improve patients' outcome. MITASREAVM cohort (unique identifier: NCT02868008, https://clinicaltrials.gov/study/NCT02868008?term=NCT02868008&rank=1 ).

How we do it? The surgical resection of a medial parietal arteriovenous malformation under multimodal imaging technology-guided hybrid operation

BACKGROUND

This report described the surgical resection of a challenging medial parietal lobe arteriovenous malformation (AVM) using the hybrid operation theater with a multimodal imaging-guided technology.

METHOD

A 29-year-old male was admitted to treat a ruptured medial parietal AVM. The deep and diffusive compartment of the nidus was embolized before resection. Preoperatively and intraoperatively, mixed reality technology with multimodality imaging was utilized for surgical planning and navigation. The nidus was totally resected and confirmed by intraoperative angiography. The patient recovered without sequella.

CONCLUSION

We hope this report provides new insights into applying multimodal imaging technology-guided hybrid operation for brain AVM.

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.

Assessing the efficacy and safety of hemangioblastoma embolization: A comprehensive systematic review and meta-analysis

BACKGROUND

Hemangioblastomas (HBs) are highly vascular tumors linked to substantial morbidity and mortality. Recently, interventional neuroradiology has evolved rapidly, spurring interest in preoperative embolization as a possible HB treatment.

PURPOSE

This study evaluates the effectiveness and safety of preoperative embolization in managing HB.

METHODS

Adhering to PRISMA guidelines, this meta-analysis considered randomized and nonrandomized studies meeting specific criteria, encompassing intracranial HB and preoperative embolization. Primary outcomes were preoperative embolization efficacy and safety. Complications were classified as major (cerebellar ischemia, ischemic strokes, intratumoral hemorrhage, subarachnoid hemorrhage) and minor (transient nystagmus, slight facial nerve palsy, nausea, transient dysarthria, hemiparesis, hemisensory impairment, thrombotic complications, extravasation).

RESULTS

Thirteen studies involving 166 patients with preoperative embolization before HB resection were included. Two studies using the Glasgow Outcome Scale (GOS) showed 5 patients with good recovery, 6 with moderate disability, and 3 with severe disability. Major complications occurred in 1% (95% CI: 0% to 3%), and minor complications occurred in 1% (95% CI: 0% to 4%). Intraoperative blood loss during resection was estimated at 464.29 ml (95% CI: 350.63 ml to 614.80 ml).

CONCLUSION

Preoperative embolization holds promise in reducing intraoperative bleeding risk in neurosurgical intracranial HB treatment, primarily due to its low complication rates. Nonetheless, additional research and larger-scale studies are essential to establish its long-term efficacy and safety. These findings highlight preoperative embolization as a valuable tool for HB management, potentially enhancing future patient outcomes.

Deliberately Staged Combined Endovascular Embolization and Subsequent Microsurgery Resection for the Treatment of Cerebral Arteriovenous Malformations

OBJECTIVE

Complex cerebral arteriovenous malformations (AVMs) require a combined therapy of endovascular embolization and microsurgical resection to eliminate the lesion and maximize neurological protection, while a deliberate time interval might contribute to optimal clinical outcomes. The present study aimed to explore the feasibility of this paradigm.

METHODS

All patients who underwent deliberately planned presurgery embolization and microsurgery resection between 2015 and 2023 were reviewed, with baseline data, postoperative complications, and follow-up outcomes recorded. The modified Rankin scale (mRS) was used to evaluate clinical outcomes, with mRS 0-2 defined as good.

RESULTS

A total of 30 patients were included in the study (15 were ruptured AVMs). The median Spetzler-Martin grade of baseline AVMs was 3 (interquartile range: 2-3). The median interval between the last embolization and microsurgery was 5 days (interquartile range: 2.25-7). The complete removal rate was 100%, and the overall permanent complication rate was 16.67%. At the last follow-up, 26 patients achieved mRS 0-2, while 28 had improved or unaltered mRS. The last follow-up mRS significantly improved from baseline and discharge (P = 0.0006 and P = 0.006). The last follow-up mRS decreased by 0.65 for each additional day of time interval before the 4.4-day inflection point (β = -0.65, P = 0.02) in the AVM ruptured cohort.

CONCLUSIONS

The deliberately staged combined procedure of embolization and microsurgery might be a safe and efficacious strategy for Spetzler-Martin grade 2-5 AVMs, 4-5 days might be an appropriate staged time interval for ruptured AVMs, although further studies are needed to substantiate these findings.

Feasibility and workflow analysis of IV-DSA-based augmented reality-guided brain arteriovenous malformation resection in a hybrid operating room: i-Flow tailored method

Augmented reality (AR) has emerged as a promising technology in various medical fields.1 2 In the context of brain arteriovenous malformation (bAVM) surgery, AR offers the potential to enhance surgical visualization and improve procedural accuracy.3 4 5 6 This report aims to explore the application of digital subtraction angiography (DSA) from an IV contrast injection (IV-DSA) in AR-guided resection of bAVMs in a neurosurgical hybrid operating room.The workflow of IV-DSA-based AR-guided surgery for the resection of bAVMs consists of four main components: (1) acquiring source images through i-Flow tailored or multiphase scans (Siemens, Germany); (2) labelling targets in the workstation using Smartbrush software (Brainlab, Westchester, Illinois, USA); (3) using the Brainlab Curve navigation system; and (4) merging microscopic AR fusion using Zeiss Kinevo (AG, Germany). In video 1 we show the entire workflow and introduce i-Flow tailored IV-DSA data acquisition in the hybrid operating room. In summary, IV-DSA-based augmented reality is an innovative technique for bAVM surgery.neurintsurg;jnis-2023-020797v1/V1F1V1Video 1-i-flow tailored iv-DSA.

The use of hybrid operating rooms in neurosurgery, advantages, disadvantages, and future perspectives: a systematic review

BACKGROUND

Hybrid operating rooms (hybrid-ORs) combine the functionalities of a conventional surgical theater with the advanced imaging technologies of a radiological suite. Hybrid-ORs are usually equipped with CBCT devices providing both 2D and 3D imaging capability that can be used for both interventional radiology and image guided surgical applications. Across all fields of surgery, the use of hybrid-ORs is gaining in traction, and neurosurgery is no exception. We hence aimed to comprehensively review the use of hybrid-ORs, the associated advantages, and disadvantages specific to the field of neurosurgery.

MATERIALS AND METHODS

Electronic databases were searched for all studies on hybrid-ORs from inception to May 2022. Findings of matching studies were pooled to strengthen the current body of evidence.

RESULTS

Seventy-four studies were included in this review. Hybrid-ORs were mainly used in endovascular surgery (n = 41) and spine surgery (n = 33). Navigation systems were the most common additional technology employed along with the CBCT systems in the hybrid-ORs. Reported advantages of hybrid-ORs included immediate assessment of outcomes, reduced surgical revision rate, and the ability to perform combined open and endovascular procedures, among others. Concerns about increased radiation exposure and procedural time were some of the limitations mentioned.

CONCLUSION

In the field of neurosurgery, the use of hybrid-ORs for different applications is increasing. Hybrid-ORs provide preprocedure, intraprocedure, and end-of-procedure imaging capabilities, thereby increasing surgical precision, and reducing the need for postoperative imaging and correction surgeries. Despite these advantages, radiation exposure to patient and staff is an important concern.

Spontaneous regression of multiple flow-related aneurysms following treatment of an associated brain arteriovenous malformation: A case report

Introduction

There is no consensus in the treatment strategy of intracranial aneurysms (IAs) associated with brain arteriovenous malformation (BAVM). In particular, it is unknown if a more aggressive approach should be considered in patients harboring a BAVM, in whom multiple aneurysms or a history of aneurysmal subarachnoid hemorrhage (aSAH) is present.

Case presentation

We report on an elderly woman harboring multiple aneurysms with a history of SAH due to rupture of an unrelated IA. On evaluation, she was also found to harbor a contralateral, left parietal convexity BAVM. Following resection of the latter, spontaneous regression of two large flow-related aneurysms was encountered.

Discussion

We discuss the therapeutic decision-making, risk stratification, and functional outcome in this patient with regard to the pertinent literature on the risk of hemorrhage in IAs associated with BAVM.

Treatment of high-grade brain arteriovenous malformations using a hybrid operating room: A prospective single-arm study

BACKGROUND

Optimal treatment of patients with high Spetzler-Martin (S-M) grade brain arteriovenous malformations (BAVMs) remains controversial. Few studies have investigated outcomes in such patients treated in a hybrid operating room (hOR).

OBJECTIVE

To examine outcomes of one-stop hybrid BAVM treatment in patients with high-grade lesions.

METHODS

We prospectively enrolled patients with high-grade BAVMs (S-M grade ≥3) aged 18-65 years who underwent one-stop hybrid BAVM treatment at our hospital between October 2016 and March 2021. High-grade BAVM patients who underwent surgery from 2010 to 2016 served as historical controls.

RESULTS

Forty-one high-grade BAVM patients underwent one-stop hybrid treatment in a hOR. Sixty-one propensity score-matched patients comprised the historical control group. The groups did not significantly differ in patient and BAVM characteristics. Intraoperative angiography in four patients of the hOR group demonstrated residual nidus that required further immediate resection. Main procedural complications included hemorrhage, neurologic deficit, and seizure. In the historical control group, diffuse angioarchitecture and arteriovenous fistula were independent risk factors for incomplete resection.

CONCLUSIONS

One-stop hybrid BAVM treatment is safe and effective for removal of high-grade BAVMs, especially those with diffuse or complex angioarchitecture. Preoperative embolization can effectively reduce blood flow while preserving motor and language function. The combined application of functional magnetic resonance imaging, electrophysiological monitoring, and awake craniotomy can successfully avoid causing neurological injury.

Peri-procedure efficacy and safety of one-stop hybrid surgery for the treatment of brain arteriovenous malformations: A single-center preliminary experience

Background

Some deficiencies and shortcomings in treatment strategies of brain arteriovenous malformation (bAVM) remain. It is worth exploring whether the one-stop hybrid surgical platform can play a positive role in the treatment of bAVM.

Objective

This study investigated short clinical and angiographic results of one-stop hybrid surgery for the treatment of bAVM.

Methods

All patients with bAVM treated with one-stop hybrid surgery were reviewed from February 2017 to December 2021. Data including demographic information, clinical conditions, characteristics of AVM, procedure details, and clinical and angiographic results were collected.

Result

In total, 150 cerebral bAVM patients received one-stop hybrid surgery; among them, 122 received surgical resection assisted by intraoperative DSA, and 28 were treated with combination surgical resection and endovascular embolization. Complete angiographic obliteration of the AVM was achieved in 136 patients (90.7%), and procedure-related death and neurological deficit rates were 7.3%. Of all relevant variables, logistic regression analysis showed that the Spetzler & Martin (S&M) score was the only factor related to the cure rate (P < 0.001) and endpoint complication rate (P = 0.007).

Conclusions

In our preliminary experience, one-stop hybrid surgery for the treatment of brain AVMs achieves a high angiographic total occlusion rate, with acceptable peri-procedure morbidity and mortality. For S&M 4 and 5 lesions, more cases and further study are needed to investigate the effects and safety of hybrid surgery.

IV and V grade arteriovenous Malformations: A multicenter surgical experience. Use of multiple grading system to predict surgical risk

OBJECTIVE

The aim of our study is to report a multicenter experience in the treatment of IV and V grade arteriovenous malformations (AVMs) and to apply commonly used grading scales for surgical risk assessment for these vascular high-grade lesions.

METHODS

Between January 2015 and December 2019, a retrospective study was conducted to identify patients undergoing microsurgical intervention for cAVMs at two Italian centers specialized in the treatment of vascular pathologies. Data on patients with Spetzler-Martin IV and V and with a score equal or more than 7 according to Lawton-Young classification were collected. Ruptured AVMs at admission were subsequently classified according to the new proposed AVICH classification.

RESULTS

A total of 20 patients with high grade (IV and V) cAVMs were enrolled in the study and the average follow-up was 36.45 months. The outcome based on mRS was favorable in 65 % of cases. The pre-operative mRS was a factor influencing clinical outcome, as well as the number of bleedings preceding the treatment, age, and nidus characteristics. S-M IV, L-Y 3 and S-M supp 7 scores were associated with good outcome. Based on the AVICH classification, for ruptured cAVMs, having a score of 9 ore less was correlated to a postoperative mRS fewer or equal than 2.

CONCLUSIONS

Surgical management for high-grade AVMs should be considered in highly selected patients with repeated bleeding or disabling symptoms. Classification systems provide an aid in selecting patients for surgery, also in grade IV and V. It is essential to establish common registers for the management of these complex vascular malformations.

Hybrid surgery for coexistence of cerebral arteriovenous malformation and primitive trigeminal artery: A case report and literature review

The primitive trigeminal artery (PTA), an abnormal carotid-basilar anastomosis, forms the vascular anomaly connection between the internal carotid artery and vertebrobasilar system. Rarely, PTA can be complicated by several other cerebrovascular disease, including arteriovenous malformations (AVMs), intracranial aneurysms, moyamoya disease, and carotid-cavernous malformations. Herein, we reported a rare case of PTA combined with an AVM in a male patient. The patient was a 28-year-old male with epileptic seizures at the onset of symptoms. Magnetic resonance imaging showed abnormal signal foci and localized softening foci formation with gliosis in the right parietal temporal lobe. Furthermore, using a digital subtraction angiogram (DSA), it was found that an abnormal carotid-basilar anastomosis had developed through a PTA originating from the cavernous portion of the right internal carotid artery (ICA) and a large AVM on the surface of the right carotid artery. The lesion of AVM tightly developed and draining into superior sagittal sinus. A hybrid operating room was used for the surgery. The main feeding arteries of the AVM originating from three major arteries, including the right middle cerebral artery, the right anterior cerebral artery, and the right posterior cerebral artery, were clipped and subsequently, then the AVM was thoroughly removed. The intraoperative DSA showed that the AVM had been resected completely. Postoperative pathological examination of the resected specimen indicated the presence of an AVM. The patient recovered well after surgery and has been symptom-free for more than 3 months. In summary, the pathogenesis of the coexistence of PTA and AVM remains unknown. As highlighted in this case report, hybrid surgery can be used to remove AVMs and can improve the patients' prognosis. To our best knowledge, this is the first case in the literature of successful AVM treatment using hybrid surgery.

Patient frailty association with cerebral arteriovenous malformation microsurgical outcomes and development of custom risk stratification score: an analysis of 16,721 nationwide admissions

OBJECTIVE

Patient frailty is associated with poorer perioperative outcomes for several neurosurgical procedures. However, comparative accuracy between different frailty metrics for cerebral arteriovenous malformation (AVM) outcomes is poorly understood and existing frailty metrics studied in the literature are constrained by poor specificity to neurosurgery. This aim of this paper was to compare the predictive ability of 3 frailty scores for AVM microsurgical admissions and generate a custom risk stratification score.

METHODS

All adult AVM microsurgical admissions in the National (Nationwide) Inpatient Sample (2002–2017) were identified. Three frailty measures were analyzed: 5-factor modified frailty index (mFI-5; range 0–5), 11-factor modified frailty index (mFI-11; range 0–11), and Charlson Comorbidity Index (CCI) (range 0–29). Receiver operating characteristic curves were used to compare accuracy between metrics. The analyzed endpoints included in-hospital mortality, routine discharge, complications, length of stay (LOS), and hospitalization costs. Survey-weighted multivariate regression assessed frailty-outcome associations, adjusting for 13 confounders, including patient demographics, hospital characteristics, rupture status, hydrocephalus, epilepsy, and treatment modality. Subsequently, k-fold cross-validation and Akaike information criterion–based model selection were used to generate a custom 5-variable risk stratification score called the AVM-5. This score was validated in the main study population and a pseudoprospective cohort (2018–2019).

RESULTS

The authors analyzed 16,271 total AVM microsurgical admissions nationwide, with 21.0% being ruptured. The mFI-5, mFI-11, and CCI were all predictive of lower rates of routine discharge disposition, increased perioperative complications, and longer LOS (all p < 0.001). Their AVM-5 risk stratification score was calculated from 5 variables: age, hydrocephalus, paralysis, diabetes, and hypertension. The AVM-5 was predictive of decreased rates of routine hospital discharge (OR 0.26, p < 0.001) and increased perioperative complications (OR 2.42, p < 0.001), postoperative LOS (+49%, p < 0.001), total LOS (+47%, p < 0.001), and hospitalization costs (+22%, p < 0.001). This score outperformed age, mFI-5, mFI-11, and CCI for both ruptured and unruptured AVMs (area under the curve [AUC] 0.78, all p < 0.001). In a pseudoprospective cohort of 2005 admissions from 2018 to 2019, the AVM-5 remained significantly associated with all outcomes except for mortality and exhibited higher accuracy than all 3 earlier scores (AUC 0.79, all p < 0.001).

CONCLUSIONS

Patient frailty is predictive of poorer disposition and elevated complications, LOS, and costs for AVM microsurgical admissions. The authors’ custom AVM-5 risk score outperformed age, mFI-5, mFI-11, and CCI while using threefold less variables than the CCI. This score may complement existing AVM grading scales for optimization of surgical candidates and identification of patients at risk of postoperative medical and surgical morbidity.

Intraoperative Monitoring Cerebral Blood Flow During the Treatment of Brain Arteriovenous Malformations in Hybrid Operating Room by Laser Speckle Contrast Imaging

Background

Hemodynamic changes caused by hybrid surgery for brain arteriovenous malformations (bAVM) are usually related to long-term lesions from "blood stealing". There are currently no viable low-cost, noninvasive procedures for assessing cerebral perfusion in the operating room. This study aims to investigate the use of intraoperative laser speckle contrast image (LSCI) software in AVM surgery.

Methods

In Zhongnan Hospital of Wuhan University, 14 patients who underwent surgery with LSCI were collected. To analyze the hemodynamic features of AVM and the influence on the peripheral cortex of AVM embolization and resection, we assessed the transit time between feeding arteries and drainage veins by intraoperative digital subtraction angiography (DSA). Meanwhile, LSCI was performed at pre-embolization, post-embolization, and after complete resection of bAVM.

Results

In this study, the transit time of bAVM before and after embolization was compared, the transit time before embolization was significantly shorter than that after embolization (p < 0.05). We also got good visualization of relative CBF, in addition, to flow imaging in the cortical vasculature round bAVM with LSCI. The flux of post-surgery was significantly higher than pre-embolization (p < 0.01).

Conclusion

Hemodynamic variable assessment plays an important role in the resection of AVM in the hybrid operative room and LSCI can be used to visualize and evaluate cortical cerebral blood flow to detect pathological hyperperfusion in real-time with a good spatial-temporal resolution in a sensitive and continuous, non-invasive mode.

Multimodality Treatment of Brain Arteriovenous Malformations with One-Staged Hybrid Operation: Clinical Characteristics and Long-Term Prognosis

Objective

We aimed to evaluate the clinical characteristics and long-term prognosis of brain arteriovenous malformations (bAVMs) treated with multimodality management of one-staged hybrid operation.

Methods

We identified bAVM patients treated with one-staged hybrid operation from a multicenter prospective cohort study (NCT03774017) between January 2016 and June 2020. Patients were divided into unruptured and ruptured groups by the hemorrhagic presentation. Long-term (>12 months) neurological disability, postoperative complications of stroke, and nidus obliteration were evaluated and compared between groups. Prognostic predictors associated with outcomes were analyzed.

Results

A total of 130 patients were identified in the study receiving one-staged hybrid operations, including 61 unruptured cases and 69 ruptured cases. Mean age was 29.1 years old, with 78 (60.0%) being male. Patients included in the study were followed up for a mean period of 37.4 (11.07) months. The annual hemorrhagic risk was 4.2% per year. Thirteen postoperative stroke events were detected in 11 patients (8.5%). Long-term disability occurred in 6.9% of cases, and 86.2% of patients experienced an unchanged or improved neurological status at the last follow-up. All patients achieved complete obliteration on follow-up angiographies. Increased AVM volume was associated with a higher risk of postoperative stroke (odds ratio (OR) 1.021, 95% confidence interval (CI) 1.006-1.037, and P = 0.006). Poor neurological status (OR 6.461, 95% CI 1.309-31.889, and P = 0.022) and infratentorial location (OR 5.618, 95% CI 1.158-27.246, and P = 0.032) were independent predictors for long-term disability.

Conclusions

One-staged hybrid operation of embolization combined microsurgical resection can be performed as a safe and effective strategy for bAVM treatments. Long-term prognosis of complete obliteration with low rates of morbidity and mortality can be achieved. Unruptured and ruptured bAVMs acquired similar favorable outcomes after the multimodality treatment.

Three-Dimensional Printing Assisted Preoperative Surgical Planning for Cerebral Arteriovenous Malformation

Objective

The aim of this study to investigate the benefits of patient-based 3-dimensional (3D) cerebral arteriovenous malformation (AVM) models for preoperative surgical planning and education.

Methods

Fifteen patients were operated on for AVMs between 2015 and 2019 with patient-based 3D models. Ten patients’ preoperative cranial angiogram screenings were evaluated preoperatively or perioperatively via patient-based 3D models. Two patients needed emergent surgical intervention; their models were solely designed based on their AVMs and used during the operation. However, the other patients who underwent elective surgery had the modeling starting from the skull base. These models were used both preoperatively and perioperatively. The benefits of patients arising from treatment with these models were evaluated via patient files and radiological data.

Results

Fifteen patients (10 males and five females) between 16 and 66 years underwent surgery. The mean age of the patients was 40.0±14.72. The most frequent symptom patients observed were headaches. Four patients had intracranial bleeding; the symptom of admission was a loss of consciousness. Two patients (13.3%) belonged to Spetzler-Martin (SM) grade I, four (26.7%) belonged to SM grade II, eight (53.3%) belonged to SM grade III, and one (6.7%) belonged to SM grade IV. The mean operation duration was 3.44±0.47 hours. Three patients (20%) developed transient neurologic deficits postoperatively, whereas three other patients died (20%).

Conclusion

Several technological innovations have emerged in recent years to reduce undesired outcomes and support the surgical team. For example, 3D models have been employed in various surgical procedures in the last decade. The routine usage of patient-based 3D models will not only support better surgical planning and practice, but it will also be useful in educating assistants and explaining the situation to the patient as well.

Clinical outcomes of procedures combining endovascular embolization with a direct surgical approach in a hybrid operating room for the treatment of refractory dural arteriovenous fistulas

Background:

We reviewed the clinical outcomes of a procedure that combines endovascular embolization and a direct surgical approach in a hybrid operating room (OR) for the treatment of refractory dural arteriovenous fistulas (dAVFs).

Methods:

All patients with intracranial dAVFs who underwent a procedure combining endovascular embolization and direct surgical approach with biplane angiography or a robotic C-arm system in a hybrid OR between February 2004 and June 2020 were considered. Borden grading, occlusion rate, pre-and post-operative modified Rankin Scale (mRS) scores, and complications were retrospectively investigated. The pre-and postoperative mRS scores were compared using the Wilcoxon signed-ranks test.

Results:

We evaluated 14 arteriovenous fistulas (AVFs) in consecutive 13 patients. Of these, ten AVFs were previously treated with endovascular embolization, ten were located in the transverse-sigmoid sinus, and four in the cortical vein. The Borden grade was II in two AVFs and III in 12 AVFs. Immediate occlusion of the AVF was achieved in 13 AVFs, and gradual occlusion was observed in one case. The median preoperative mRS was 1 (0–3), whereas the median postoperative mRS was 0 (0–1) which indicated marked improvement (P = 0.006). Complications including postoperative transient visual disturbance and intraprocedural extravasation were observed in only two cases.

Conclusion:

The combination of endovascular embolization and direct surgical approach in a hybrid OR could achieve sufficient occlusion of refractory AVFs with acceptable complication rates and improved symptoms.

Chinese Cerebrovascular Neurosurgery Society and Chinese Interventional & Hybrid Operation Society, of Chinese Stroke Association Clinical Practice Guidelines for Management of Brain Arteriovenous Malformations in Eloquent Areas

Aim: The aim of this guideline is to present current and comprehensive recommendations for the management of brain arteriovenous malformations (bAVMs) located in eloquent areas. Methods: An extended literature search on MEDLINE was performed between Jan 1970 and May 2020. Eloquence-related literature was further screened and interpreted in different subcategories of this guideline. The writing group discussed narrative text and recommendations through group meetings and online video conferences. Recommendations followed the Applying Classification of Recommendations and Level of Evidence proposed by the American Heart Association/American Stroke Association. Prerelease review of the draft guideline was performed by four expert peer reviewers and by the members of Chinese Stroke Association. Results: In total, 809 out of 2,493 publications were identified to be related to eloquent structure or neurological functions of bAVMs. Three-hundred and forty-one publications were comprehensively interpreted and cited by this guideline. Evidence-based guidelines were presented for the clinical evaluation and treatment of bAVMs with eloquence involved. Topics focused on neuroanatomy of activated eloquent structure, functional neuroimaging, neurological assessment, indication, and recommendations of different therapeutic managements. Fifty-nine recommendations were summarized, including 20 in Class I, 30 in Class IIa, 9 in Class IIb, and 2 in Class III. Conclusions: The management of eloquent bAVMs remains challenging. With the evolutionary understanding of eloquent areas, the guideline highlights the assessment of eloquent bAVMs, and a strategy for decision-making in the management of eloquent bAVMs.

Quality improvement of nursing on patients with complex cerebral arteriovenous malformation undergoing hybrid surgery: a prospective single-center study

Background

We sought to explore an optimal clinical nursing mode following a hybrid surgery for cerebral arteriovenous malformation.

Methods

Patients with complex cerebral arteriovenous malformations seen in our neurosurgery department from January 2016 to December 2017 were prospectively enrolled. The hybrid surgery protocol included “angiographic diagnosis, surgical resection, and intraoperative angiographic evaluation” and “angiographic diagnosis and embolization, surgical resection, and intraoperative angiographic evaluation”. The patients were randomly stratified into intensive care group and routine care group. After surgery, intensive or routine care was provided, and the prognosis of patients was evaluated, with a subsequent comparative analysis.

Results

A total of 109 cases were divided into the routine nursing group (n = 54 cases) and intensive nursing group (n = 55 cases). There were no significant differences between the two groups in baseline data before surgery. Postoperative lung infection in the intensive nursing group was significantly less frequent than those in the routine nursing group (5.5% vs. 18.5%, P=0.039) with pulmonary infection and lower extremity venous thrombosis (5.5% vs. 24.1%, P=0.006). The average hospital stay in the intensive nursing group was 14.4 ± 5.78 days, which was significantly lower than that in the routine nursing group (19.3 ± 6.38 days, P=0.013). At 3 months’ follow-up after surgery, the Generic Quality of Life Inventory-74 (GQOLI-74) dimension score and GQOLI-74 total score in the enhanced group were significantly better than those in the routine nursing group (P=0.017 and 0.023, respectively).

Conclusions

Intensive postoperative nursing can improve the safety of patients after hybrid surgery, reduce the postoperative complications and the average length of hospital stay, and improve the quality of life of patients.

A systematic review on the application of the hybrid operating room in surgery: experiences and challenges

The hybrid operating room has been widely applied in different surgery sub-specialties. We aim to identify the advantages of hybrid operating rooms by focusing on intraoperative imaging and explore what to do for further improving its application. We searched related literature in websites including Pubmed, MEDLINE, Web of science, using the keywords ("hybrid operating room" or "integrated operating room" or "multifunctional operating room") and ("surgery" or "technique" or "intervention" or "radiology"). All the searched papers were screened and underwent quality evaluation. A total of 30 literature was eventually identified after full-text screening. These articles covered 10 countries and presented data for 15,558 individuals. The median sample size was 536 (range 8-12,804). Application of the hybrid operating room in general surgery, neurosurgery, thoracic surgery, urology, gynaecologic and obstetrics surgery, cardiovascular surgery, was summarized. Four different operative indicators were applied (operative duration, mortality rate, operation success rate and complication rate). A hybrid OR could significantly increase the operation success rate and reduce operative duration, mortality rates, and complication rates. Further efforts could be made to reduce radiation exposure in the hybrid operating room and increase its cost-effectiveness ratio.

Systematic review of brain arteriovenous malformation grading systems evaluating microsurgical treatment recommendation

When evaluating brain arteriovenous malformations (bAVMs) for microsurgical resection, the natural history of bAVM rupture must be balanced against the perioperative risks. It is therefore adamant to have a reliable surgical grading system, balancing these important factors. This study systematically reviews the literature in order to identify and assess the quality of grading systems with regard to microsurgical bAVM treatment. A systematic literature review was performed to provide an overview of all available bAVM grading systems relevant for microsurgical treatment evaluation and to assess the most comprehensive grading system specifically for each subgroup of bAVM (i.e., unruptured, ruptured, and posterior fossa). Screening of 865 papers revealed thirteen grading systems for bAVM microsurgical risk stratification. Among them, two systems were specifically developed for ruptured bAVM and one specifically for posterior fossa bAVM. With one system being fundamentally different for supratentorial bAVM, the remaining nine systems used the same parameters: “size,” “eloquence,” “venous drainage,” “arterial feeders,” “age,” “nidus compactness,” and “hemorrhagic presentation”. This study provides a comprehensive overview of all available bAVM grading systems relevant for surgical risk stratification. Furthermore, in the absence of a universal system appropriate to score all bAVMs, a workflow for selection of the best applicable scoring system in accordance with bAVM subgroups is presented.

Usefulness of Hybrid Surgery Combining CEA and CAS for Carotid Artery Stenosis with a Large Amount of Vulnerable Plaque

Objective

For carotid artery stenosis with a large amount of vulnerable plaque in a wide range, we performed a hybrid surgery combining carotid endarterectomy (CEA) and carotid artery stenting (CAS), and report the results of treatment.

Methods

Surgical treatment for carotid artery stenosis in 216 patients was performed between January 2016 and June 2018. Of these, 15 patients were treated in a hybrid operating room because both CEA and CAS were judged to be risky. We treated these patients with preparation of stenting for remote lesions far from the CEA arterial incision. The perioperative treatment results were retrospectively examined.

Results

Of the 15 patients treated in a hybrid operating room, 10 were stented after CEA. All these cases were treated by retrograde stent placement in the proximal common carotid artery (CCA). Treatment was completed in all patients, and no cerebral infarction, myocardial infarction, or death was observed in the perioperative period. There were no cases of additional neurological events during the follow-up period, but asymptomatic restenosis was observed in one patient.

Conclusion

Hybrid surgery combining CEA and CAS was considered to be an effective treatment for carotid artery stenosis with a large amount of vulnerable plaque.

One-Stage Treatment in a Hybrid Operation Room to Cure Brain Arteriovenous Malformation: A Single-Center Experience

OBJECTIVE

To report the principles and techniques of using a hybrid operation room in the treatment of brain arteriovenous malformation (BAVM).

METHODS

From October 1, 2016 to December 31, 2018, we treated 54 consecutive patients with nonemergent BAVM in a hybrid operation room. The clinical data, radiologic images, and outcomes were collected to establish a prospective database for evaluation.

RESULTS

Thirty-two male and 22 female patients were enrolled with a mean age of 32.6 ± 13.1 years (range, 10-61 years). Bleeding (n = 32, 59.3%) was the main clinical presentation, followed by headache (n = 27, 50.0%), seizures (n = 14, 25.9%), neurofunctional deficits (n = 16, 29.6%), and no symptoms (n = 2, 3.7%). Thirty-one patients (57.4%) accepted resection without intraoperative embolization, 18 (33.3%) were treated with combined embolization and resection, and 5 (9.3%) were cured with intraoperative embolization and resection was cancelled. All patients achieved total BAVM obliteration confirmed with intraoperative angiography. There were no significant differences in outcomes between low-grade (Spetzler-Martin grades I, II, and modified grade III-) and high-grade (Spetzler-Martin grades ≥IV and modified grade III+) groups, except that the high-grade group had more blood loss (667.9 ± 647.5 vs. 284.3 ± 148.6 mL; P = 0.046) and longer postoperative hospitalization (17.1 ± 9.1 vs. 10.8 ± 5.4 days; P = 0.026). At discharge, 52 patients (96.3%) had favorable outcomes (Glasgow Outcome Scale score ≥4). Forty-three patients (79.6%) received 1 year follow-up after treatment; 97.7% (n = 42) of these had ongoing favorable outcomes. However, 4 patients with low-grade BAVM had recurrence.

CONCLUSIONS

The hybrid operation room can ensure safe, comprehensive treatment of BAVM, offering the opportunity for a favorable curative treatment in 1 stage.

Application of the Hybrid Operating Room in Surgery: A Systematic Review

BACKGROUND AND OBJECTIVE

The hybrid operating room has been widely applied in surgery, including neurology, general surgery, gynecology, and obstetrics. By reviewing application of the hybrid operating room in different categories of surgery, we aim to summarize both advantages and disadvantages of the hybrid operating room and discuss what to do for further improving the application of it.

METHODS

We searched related literature in websites including Pubmed, MEDLINE, Web of science, using the keywords "hybrid operating room", "surgery", "technique", "intervention", and "radiology". All the searched papers were screened and underwent quality evaluation. The eventually selected papers were carefully read, with related information extracted and summarized.

RESULTS

After screening and assessment, a total of 29 literature was collected. Application of the hybrid operating room in general surgery, neurosurgery, thoracic surgery, urology, gynecologic and obstetrics surgery, and cardiovascular surgery was summarized. Both advantages and disadvantages of the hybrid operating room were discussed in order to improve application of the hybrid operating room in surgery.

CONCLUSIONS

Surgeries performed in the hybrid operating room take advantages over those conventional operating rooms mainly in terms of higher procedure accuracy, less operative time, and less risk of hemorrhage during the transportation between radiology departments and operating suites. Further efforts should be made to reduce radiation exposure from imaging systems equipped in the hybrid operating room and increase cost-effectiveness ratio of the hybrid operating room.

Single-Stage Combined Embolization and Resection for Spetzler-Martin Grade III/IV/V Arteriovenous Malformations: A Single-Center Experience and Literature Review

Background and Purpose: This study sought to identify the efficacy and intraoperative operational details of single-stage combined embolization and microsurgery strategy for Spetzler-Martin (SM) grade III/IV/V arteriovenous malformations (AVMs).

Methods: The authors retrospectively reviewed consecutive SM grade III/IV/V AVMs who underwent hybrid procedures and surgical resection alone procedures from January 2016 to February 2018. Outcomes [modified Rankin Scale (mRS)] were compared between hybrid group and surgical resection alone group in ruptured or unruptured subgroup. Factors associated with long-term disability were assessed using multivariable logistic regression analyses.

Results: A total of 100 AVM patients (47 corrected using hybrid procedures whereas 53 by surgical resection alone) were evaluated. After a mean follow-up of 2.3 ± 0.6 years, we found no difference in long-term prognosis and incidences of disability rates between these two strategies. However, the hybrid strategy offers significant advantage in accelerating the resection process [ruptured (P = 0.000); unruptured (P = 0.002)]. In the analysis of risk factors, excessive embolization (Grade C, 60–100%) was significantly associated with long-term disability in the hybrid cohorts (P = 0.041; odds ratio, 24.000; 95% CI, 1.140–505.194), and involvement of deep perforating arteries was the significant predictor of long-term disability in the surgical resection alone cohort (P = 0.025; odds ratio, 15.389; 95% CI, 1.412–167.66). In the subgroup analysis of the hybrid cohort, moderate embolization (Grade B, 30–60%) was recommended because of the low risk ratio of major intraoperative bleeding (P = 0.033).

Conclusions: Single-stage combined embolization and resection is an efficient strategy for the treatment of SM grade III/IV/V AVMs. Although the long-term outcomes were similar to surgical resection alone, the hybrid strategy had obvious advantages of shorter resection. In the hybrid technique, moderate embolization was recommended, and excessive embolization might be detrimental to the subsequent microsurgical resection.

Clinical Trial Registration:http://www.clinicaltrials.gov. Unique identifier: NCT04136860.

Contemporary management of brain arteriovenous malformations in mainland China: a web-based nationwide questionnaire survey

BACKGROUND

In the benefit of the large population and rapid economic growth, the interventional techniques and equipment for brain arteriovenous malformations (bAVMs) in mainland China have been rapidly improved. Chinese neurosurgical cerebrovascular physicians have accumulated rich experience and made pioneering explorations. This study aims to summarize the experience and treatment progress of bAVMs in mainland China.

METHODS

We performed a web-based nationwide questionnaire survey among 67 tertiary neurosurgical institutions that had acknowledged treating bAVMs in the primary survey. Our questionnaire included clinical characteristics, radiological findings, intervention indications/contraindications, intervention timing, and intraoperative management of different treatment modalities.

RESULTS

A total of 63 participants from 49 (73.1%) tertiary neurosurgical institutions responded to our questionnaire. Forty-two (66.7%) were neurosurgeons, 13 (20.6%) were neurointerventionists, and 8 (12.7%) were radiosurgeons. Approximately 3500 to 4000 cases of bAVMs were treated annually in these 49 departments. All participants agreed that the conclusions of ARUBA are debatable. Flow-related aneurysms, deep venous drainage, and arteriovenous fistula were considered as common hemorrhagic risk factors. Unruptured SM IV-V bAVMs, giant bAVMs, pediatric bAVMs, elderly bAVMs, and eloquent bAVMs were not absolute contraindications to intervention. Maximum lesion occlusion and minimal functional impairment were the principles of intervention management. Most of the neurosurgeons and neurointerventionists recommended early intervention (< 30 days) for ruptured bAVMs, and the radiosurgeons suggested intervention in the chronic phase or recovery phase (P < 0.01) and preferably 3 months after bleeding. Multi-modality strategies were thought effective for complex bAVMs, and more exploration of individualized intraoperative management was necessary.

CONCLUSIONS

Intervention was acceptable for specific selected unruptured bAVMs in mainland China, especially in patients with hemorrhagic risk factors. The application of multidisciplinary cerebrovascular team and multicenter large-sample international registry study might be the next work for Chinese neurosurgical cerebrovascular physicians.

A combined single-stage procedure to treat brain AVM

Complete resection of brain arteriovenous malformation (AVM) is a surgical challenge, mainly due to risk of intraoperative rupture. The objective of this feasibility study was to analyze complete resection rate at 3 months and clinical outcome at 6 months after treatment of brain AVM by combined single-stage embolization and surgical resection. A retrospective observational study from July 2015 to February 2019 was conducted at the Department of Neurosurgery of Strasbourg University Hospital, France. Decision to treat was taken on the basis of history of AVM rupture, symptomatic AVM, or morphologic risk factors for rupture. Complete resection rate was assessed on postoperative cerebral subtraction angiography at 3 months and clinical outcome at 6 months was evaluated on the modified Rankin Scale (mRS). In the 16 patients treated for symptomatic brain AVM, the rate of complete resection was 75%, resection with residual shunt 18.7%, and incomplete resection with residual nidus 6.3%. Good clinical outcome (mRS=0 or 1) was achieved in 81.3% of patients at 6 months. The transfusion rate was 7.1%. There were procedural complications in 12.5% of patients but no intraoperative ruptures. This combined single-stage procedure allows extensive preoperative embolization of the AVM, facilitating surgical microdissection by identifying the dissection plane and perforating arteries and allowing the operator to work in close contact with the nidus without fear of intraoperative rupture.

Pre-Surgical Endovascular Proximal Feeder Artery Devascularization Technique for the Treatment of Cranial Arteriovenous Malformations

Objective

Treatment of brain arteriovenous malformations (AVMs) aims to abolish any risk for intracranial hemorrhage with the preservation of the patient’s functional status. We present the technique of pre-surgical endovascular devascularization through proximal feeder artery occlusion for the treatment of cranial AVMs rather than nidus occlusion. Also, we highlight the advantages and the possible clinical indications.

Patients and Methods

Two patients with brain AVM and one patient with scalp AVM were treated by pre-surgical endovascular devascularization followed by surgical resection. Endovascular devascularization was performed by occlusion of the AVM feeders only with Liquid Embolic System Agent (Onyx^®) 18 without entering and filling the nidus. During surgery, feeding arteries colored with the black color of the Liquid Embolic System Agent were clearly identified and cut. Dissection of the AVM was performed, and resection of the nidus was achieved.

Results

Total resection of the AVM was achieved in all cases confirmed with follow-up angiographies, with no neurologic or systemic complications. Also, no major bleeding was detected. In addition, the surgical clips were avoided during surgery. Brain AVMs were safely resected in piecemeal fashion.

Conclusion

Pre-surgical endovascular proximal feeder artery devascularization technique shows to be a safe, simple and effective technique for the management of cranial arteriovenous malformations. This technique simplifies both the endovascular and surgical approaches to complicated cranial AVM cases.

One-staged in situ embolization combined with surgical resection for eloquence protection of AVM: technical note

Brain arteriovenous malformations (AVMs) near/within eloquent areas are challenging to treat surgically. The insufficient lesion-to-eloquence distance (LED) is related to poor neurological outcomes. This paper reports the use of in situ embolization combined with surgical resection in a one-staged hybrid operation for eloquent area protection. Nine patients who underwent one-staged in situ embolization combined with surgical resection were selected from the database of a prospective clinical trial (NCT03774017). Nidus got partial in situ embolization in the parts located near/within the eloquence. The rest of nidus was removed via a microsurgical procedure in the same operation. The in situ embolization ensured a sufficient LED to prevent eloquent areas and tracts from being damaged in the subsequent resection. All of the patients achieved complete obliteration with no neurological deficits or complications. One-staged hybrid operation initiates closer cooperation between surgical and endovascular treatments and proposes an integrative therapeutic mode for AVMs. The in situ embolization combined with surgical resection is safe and effective for improving the functional outcome of AVMs with eloquence and tracts involved. The clinical trial is registered at ClinicalTrials.gov (NCT03774017, https://clinicaltrials.gov/ct2/show/NCT03774017 ).

Intraoperative Computed Tomography Versus Fluoroscopy for Ventriculoperitoneal Shunt Placement

OBJECTIVE

Catheter malposition represents one of the major causes of ventriculoperitoneal (VP) shunt dysfunction. The usefulness of intraoperative fluoroscopy using skull landmarks has already been proved to decrease catheter malposition and surgical revision rates. After introducing intraoperative computed tomography (iCT) in our department, our objective was to evaluate the accuracy of this imaging modality to decrease cranial catheter misplacement compared with intraoperative fluoroscopy.

METHODS

In our retrospective analysis of 152 patients, catheter placement was evaluated by iCT (n = 48) and biplane fluoroscopy (n = 57). A control group (n = 47) had no intraoperative imaging. Outcome measures included accuracy of ventricular catheter position, revision surgeries, and clinical outcomes.

RESULTS

Ventricular catheter placement was accurate in 24/48 patients with iCT and 45/57 patients with fluoroscopy (P = 0.002) versus 23/47 patients in the control group. Sensitivity and positive predictive value for estimating optimal catheter position with iCT were 100% and 54%. The specificity and negative predictive value were 50% and 100%. After intraoperative revision, 4 catheters remained malpositioned in the iCT group, whereas the fluoroscopy group had none (P = 0.03); 2 of these 4 catheters were revised postoperatively.

CONCLUSIONS

Fluoroscopy may be the method of choice to intraoperatively assess ventricular catheter positioning. In our experience, iCT shows a tendency to be more time consuming and, in the beginning, was not associated with a steeper learning curve. Another consideration was the significant higher radiation exposure per patient. iCT did not improve the accuracy of catheter placement and did not decrease early revisions for VP placement patients.