Clinical experience in intracranial stenting of Wingspan stent system under local anesthesia.

Objective: The use of endovascular treatments for symptomatic intracranial atherosclerosis disease (ICAD) remains contentious due to high periprocedural complications. Many centers resort to general anesthesia for airway protection and optimal periprocedural conditions; however, this approach lacks real-time monitoring of patients' neurological status during procedures. In this study, we employed intracranial stenting with the Wingspan system under local anesthesia to address this challenge. Methods: We conducted a retrospective study of 45 consecutive ICAD patients who underwent intracranial stenting with the Wingspan system at our hospital from August 2013 to May 2021. These stenting procedures were performed under local anesthesia in a hybrid operation room. Neurological assessments were conducted during the procedure. The patients with periprocedural complications were analyzed for the risk factors. Results: The study included 45 ICAD patients (median age 62 years; 35 male and 10 female individuals). Among them, 30 patients had anterior circulation ICAD, and 15 had posterior circulation ICAD. The periprocedural complication rate was 8.9% (4/45), with an overall mortality rate of 2.2% (1/45). Notably, no procedure-related perforation complications were found, and all ischemic complications occurred in the perforating bearing artery, specifically in patients with stents placed in the middle cerebral artery or basilar artery, while no complications were observed in the non-perforating bearing artery of the internal carotid artery and vertebral artery (p = 0.04). Conclusion: Our study demonstrates the safety and efficacy of the Wingspan stent system when performed on selected patients under local anesthesia. This approach seems to reduce procedural-related morbidity and be a safe intervention. In addition, it is crucial for surgeons to be aware that patients with perforator-bearing artery stenosis may be at a higher risk of complications.

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.

Intraoperative Augmented Reality in Microsurgery for Intracranial Arteriovenous Malformation: A Case Report and Literature Review.

BACKGROUND: Intracranial arteriovenous malformations (AVMs) are lesions containing complex vessels with a lack of buffering capillary architecture which might result in hemorrhagic cerebrovascular accidents (CVAs). Intraoperative navigation can improve resection rates and functional preservation in patients with lesions in eloquent areas, but current systems have limitations that can distract the operator. Augmented Reality (AR) surgical technology can reduce these distractions and provide real-time information regarding vascular morphology and location. METHODS: In this case report, an adult patient was admitted to the emergency department after a fall, and diagnostic imaging revealed a Spetzler-Martin grade I AVM in the right parietal region with evidence of rupture. The patient underwent a stereotactic microsurgical resection with assistance from augmented reality technology, which allowed for a hologram of the angioarchitecture to be projected onto the cortical surface, aiding in the recognition of the angiographic anatomy during surgery. RESULTS: The patient's postoperative recovery went smoothly. At 6-month follow-up, the patient had remained in stable condition, experiencing complete relief from his previous symptoms. The follow-up examination also revealed complete obliteration of the AVMs without any remaining pathological vascular structure. CONCLUSIONS: AR-assisted microsurgery makes both the dissection and resection steps safer and more delicate. As several innovations are occurring in AR technology today, it is likely that this novel technique will be increasingly adopted in both surgical applications and education. Although certain limitations exist, this technique may still become more efficient and precise as this novel technology its continues to develop further.

Intraoperative DSA-guided minimal approach for craniocervical junction DAVFs obliteration.

BACKGROUND: Dural arteriovenous fistulas (DAVFs) are a group of diseases involving problematic shunts between dural arteries and venous structures such as sinuses, meningeal veins, or even cortical veins. To focus on craniocervical junction dural arteriovenous fistulas (DAVFs), we introduce a minimally invasive technique with midline incision combined with intraoperative digital subtraction angiography (DSA). This hybrid technique can minimize the incision wound to an average of 6 cm which leads to less destruction and lower risk of adverse events. METHOD: Using this minimally invasive approach, surgical obliteration was achieved in 6 patients with craniocervical junction DAVFs. A minimal midline incision was made over the C1-2 level, measuring approximately 5 to 7 cm in length. C1 hemilaminectomy was performed for DAVF obliteration followed by intraoperative DSA for confirmation of complete obliteration. RESULTS: Among these 6 patients, the radiculomedullary artery was the most common feeding artery. The mean length of the operation (including DSA performance) was 6.5 ± 1.4 h. None of these cases showed cerebrospinal fluid leakage or exacerbation of neurological symptoms after the operation. CONCLUSION: Using intraoperative DSA, the minimally invasive technique offers more precise but less destructive access than conventional far lateral suboccipital craniotomy. Most importantly, intraoperative DSA provided verification of complete closure for shunts that could not be examined for indocyanine green (ICG) dye because the microscope did not have a clear line of sight. In our experience, this technique shows encouraging results of fistula obliteration.

Maintaining the Quality of Mechanical Thrombectomy after Acute Ischemic Stroke in COVID(-)19 Patients.

The COVID-19 pandemic has become increasingly worse worldwide since it was discovered in China in late December 2019. Easy contact transmission between people and a low to moderate mortality rate may cause failure in medical health services if there is no proper personal protective equipment for personnel. During the pandemic, patients with acute ischemic stroke with large-vessel occlusion who required immediate treatment through mechanical thrombectomy (MT) were still being sent to the emergency room. Knowing how to maintain effective treatment standards has become our concern. We used a retrospective, single-center study to select COVID-19 (-) patients with acute ischemic stroke undergoing mechanical thrombectomy during the years 2020-2021. Patients with acute ischemic stroke with large-vessel occlusion received mechanical thrombectomy were compared with patients admitted from December 2020 to May 2021 (the pre-COVID-19 group) and those from June 2021 to November 2021 (the during COVID-19 group). Furthermore, the time disparity of mechanical thrombectomy was compared between these two groups. Of patients confirmed with acute ischemic stroke (AIS) with large-vessel occlusion (LVO) during the study period, 62 were included. Compared with the pre-COVID-19 group (34 patients; median age, 70.5 years), the during COVID-19 group (28 patients; median age, 71.5 years) showed no major median time difference in door-to-computed-tomography-angiography (CTA) time (19.0 min vs. 20.0 min, p = 0.398) and no major median time difference in door-to-groin-puncture time (118.0 min vs. 109.0 min, p = 0.281). In our study, with a prepared protocol for the pandemic having been established in the healthcare system, we could see no difference between the pre-pandemic and during-pandemic time periods when using mechanical thrombectomy to treat COVID-19 (-) patients of AIS with LVO. By means of a quick-PCR test during triage, there was no time delay to perform MT or any lowering of safety protocol for workers in the healthcare system.

Lumbrokinase regulates endoplasmic reticulum stress to improve neurological deficits in ischemic stroke.

Ischemic stroke is characterized by the loss of cerebral blood flow, which frequently leads to neurological deficits. Tissue plasminogen activator is the only therapeutic agent approved to treat ischemic stroke but increases the risk of intracranial hemorrhage and mortality. The fibrinogen-depleting agent lumbrokinase has been used to improve myocardial perfusion in symptomatic stable angina and to prevent secondary ischemic stroke. Lumbrokinase is highly fibrin-specific and only active in the presence of fibrin. Therefore, lumbrokinase has a low risk of hemorrhage due to excessive fibrinolysis. In this study, we aimed to clarify the neuroprotection of lumbrokinase in mice subjected to permanent middle cerebral artery occlusion. Lumbrokinase significantly attenuated infarct volume and improved neurological dysfunction. Lumbrokinase dramatically decreased the expressions of the endoplasmic reticulum (ER) transmembrane receptor protein inositol-requiring enzyme-1 (IRE1) and its downstream transcription factor, XBP-1, caspase-12, and NF-κB activity, thereby significantly inhibiting apoptosis and autophagy and decreasing the NLRP3 inflammasome. Our evidence indicates that post-stroke treatment with lumbrokinase protects against ischemic stroke, thereby regulating ER stress through the collective inhibitory effect of the IRE1 signaling pathways to decrease apoptosis, autophagy, and inflammatory responses. We suggest that lumbrokinase is potential as an adjuvant treatment for ischemic stroke.

Gamma Knife Radiosurgery for Indirect Dural Carotid-Cavernous Fistula: Long-Term Ophthalmological Outcome.

Objective: The leading treatment option for dural carotid−cavernous sinus fistula is an endovascular approach with immediate improvement. Alternatively, radiosurgery is a slow response for obliterating the fistula and poses a radiation risk to the optic apparatus and the associated cranial nerves and blood vessels. In this study, we retrieved cases from a prospective database to assess the ophthalmological outcomes and complications in treating dural carotid cavernous sinus fistula with gamma knife radiosurgery (GKRS). Material and Methods: We retrieved a total of 65 cases of carotid cavernous sinus fistula treated with GKRS with margin dose of 18−20 Gy from 2003 to 2018 and reviewed the ophthalmological records required for our assessment. Results: The mean target volume was 2 ± 1.43 cc. The onset of symptom alleviated after GKRS was 3.71 ± 7.68 months. There were two cases with residual chemosis, two with cataract, two with infarction, one with transient optic neuropathy, and four with residual cranial nerve palsy, but none with glaucoma or dry eyes. In MRA analysis, total obliteration of the fistula was noted in 64 cases with no detectable ICA stenosis nor cavernous sinus thrombosis. In the Cox regression analysis, post-GKRS residual cranial nerve palsy was highly correlated to targeted volume (p < 0.05) and age (p < 0.05). The occurrence of post-GKRS cataract was related to the initial symptom of chemosis (p < 0.05). Conclusion: GKRS for carotid cavernous sinus fistula offers a high obliteration rate and preserves the cavernous sinus vascular structure while conferring a low risk of treatment complications such as adverse radiation risk to the optic apparatus and adjacent cranial nerves.

Compressive optic neuropathy caused by a flow-diverter-occluded-but-still-growing supraclinoid internal carotid aneurysm: illustrative case.

BACKGROUND: Flow diverter stenting is an effective treatment for large proximal internal carotid artery (ICA) aneurysms. Cranial neuropathy caused by the mass effect of the aneurysm usually subsides over time. However, a new onset of compressive optic neuropathy after successful flow diverter stenting of a large proximal ICA aneurysm is seldom reported. OBSERVATIONS: A 57-year-old woman had a right supraclinoid ICA aneurysm (approximately 17 mm) on magnetic resonance angiography (MRA) in a health checkup. She received intervention with the Pipeline embolization device. Six months later, she started to experience progressive hemianopia in the left half of the visual field. Nine months after stenting, MRA showed that the aneurysm was growing and causing mass effect, but digital subtraction angiography confirmed that the aneurysm was completely excluded from the circulation. She received a craniotomy for microsurgical decompression of the optic nerve and coagulation shrinkage of the aneurysm. Clipping and thrombectomy were not attempted. Her visual fields recovered gradually. Follow-up MRA showed that the aneurysm also diminished in size. LESSONS: Whether the coagulation technique of the flow-diverter-occluded aneurysm alone is enough to cause satisfactory shrinkage and interaction between the flow diverter and the aneurysmal vasa vasorum/neointima formation should be further examined.

Penumbra volume predicts unfavorable outcome in patients with acute minor stroke or transient ischemic attack.

BACKGROUND: A subgroup of patients with acute minor stroke (AMS) or transient ischemic attack (TIA) become disabled due to disease progression (DP) or recurrent stroke within 3 months. The aim of this article is to identify the risk factors for DP in AMS/TIA patients. In the literature, no studies focused on computed tomography perfusion (CTP) in AMS/TIA patients at the acute stage. METHODS: This retrospective study included patients with AMS or TIA (onset of symptoms ≤4.5 hours, baseline National Institutes of Health Stroke Scale [NIHSS] score of 0-4). DP was defined as a deterioration of NIHSS score of ≥2 points during hospitalization or modified Ranking Scale ≥2 at 3-month follow-up. Clinical data and imaging results were retrieved and measured for statistical analysis. RESULTS: From 2011 to 2017, total 135 patients were eligible for further analysis: 28 patients (20.7%, DP group) and 107 patients (79.3%, non-DP group). The DP group had significantly higher larger penumbra volumes (p = 0.028). In univariate model of the logistic regression, patients with the following risk factors tended to have unfavorable outcome: female gender, higher HbA1c, chronic kidney disease stage ≥3b, intracranial atherosclerosis, and penumbra volume were associated unfavorable outcome, but larger deadcore volume was not. In further multivariate analysis, only penumbra volume >5 cm (p = 0.049, odds ratio [OR] = 3.21, 95% CI: 1.00-10.27) had the statistical significance. The cut-point value of the penumbra volume for unfavorable outcome in AMS/TIA patients was 4.73 cm. CONCLUSION: One fifth of the AMS/TIA patients had unfavorable outcome at 90 days. In CTP performed within 4.5 hours after the onset of AMS/TIA, the penumbra volume (>5 cm) was a significant risk factor for DP, and the cut-point value was 4.73 cm. Further studies could be designed to involve this subgroup of patients for more aggressive treatment.

Endovascular Mechanical Thrombectomy and On-Site Chemical Thrombolysis for Severe Cerebral Venous Sinus Thrombosis.

Cerebral venous sinus thrombosis (CVST) is a rare cause of cerebral infarction. Once patients survive the acute phase, long-term prognosis is generally satisfactory. CVST patients who harbored risk factors known for poor prognosis (e.g., deterioration of consciousness/neurological functions and seizures) were oftentimes unresponsive to systemic heparin treatment. The advantage of combined endovascular mechanical thrombectomy (EMT) and on-site chemical thrombolysis (OCT) plus systemic heparin for CVST over the heparin treatment alone has not been proved. A retrospective study was conducted to analyze consecutive patients with CVST from 2005 to 2015. Patients having clinical improvement or stable disease after heparin treatment were in I/S group; patients having continuous deterioration of consciousness/neurological functions and refractory seizures (despite the use of multiple anti-epileptic drugs) after heparin treatment were in D group. EMT and OCT were indicated for patients in D group. Imaging studies and medical records were reviewed for statistical analysis. Safety issues included new-onset/progression of symptomatic intracerebral hemorrhages (ICH) or procedure-related complications. Total thirty patients were included (I/S group = 16; D group = 14). In D group, the mean time frame from the start of heparin treatment to the endovascular treatment was 3.2 days. Compared with I/S group, all patients in D group had complete stenosis of the sinuses, with higher initial mRS, lower initial GCS, and more seizures (p = 0.006, 0.007, and 0.031, respectively), but no significant differences in the mRS at discharge (p = 0.504). Shorter length of thrombosis and lower initial mRS were associated with better outcomes (p = 0.009 and 0.003, respectively). Thrombosis involving the superior sagittal sinus (SSS) was associated with bad outcomes (p = 0.026). There were two patients (6.7%) with worsening symptomatic ICH, one in each group, managed surgically. The overall mortality of the study was 6.7% (2/30). Combined EMT and OCT after heparin treatment for severe CVST were reasonably safe, which might be considered as a salvage treatment in severe CVST patients who are unresponsive to heparin with heavy clot burden involving SSS in the acute phase. However, further studies are needed to confirm its efficacy and validity.

CTA-guided outflow-targeted embolization of direct carotid-cavernous fistula.

This video presents a case of new-onset visual blurring, diplopia, and conjunctival injection after head injury. CTA of the brain revealed a direct carotid-cavernous fistula (dCCF) of the right side. Careful evaluation of CTA source images revealed that the fistula point was at the ventromedial aspect of the right cavernous internal carotid artery (ICA), about 3.6 × 3.6 mm2 in size, with 3 main outflow channels (2 intracranial and 1 extracranial) (CTA-guided concept). DSA of the brain also confirmed the diagnosis but was unable to locate the fistula point in a large-sized dCCF. Through a transfemoral artery approach, 3 microcatheters were navigated to each peripheral channel to initiate outflow-targeted embolization. Intracranial refluxes were blocked first to avoid cerebral hemorrhages, followed by the extracranial outflow. During embolization, accidental dislodge of one coil into the sphenoparietal vein occurred, but no attempt of coil retrieval was made. Complete obliteration of the dCCF was achieved, and the patient recovered well without new neurological deficits. 4D MRA at the 3-month follow-up showed no residual dCCF.The video can be found here: https://youtu.be/LH2lNVRZSPk.

Treating cerebrovascular diseases in hybrid operating room equipped with a robotic angiographic fluoroscopy system: level of necessity and 5-year experiences.

BACKGROUND: A hybrid operating room (OR) equipped with robotic angiographic fluoroscopy system has become prevalent in neurosurgery. The level of necessity of the hybrid OR in treating cerebrovascular diseases (CVD) is rarely discussed. OBJECTIVE: The authors proposed a scoring and classification system to evaluate the cerebrovascular procedures according to the level of treatment necessity for CVD in a hybrid OR and shared our 5-year experiences. METHODS: From December 2009 to January 2016, the registry of cerebrovascular procedures performed in the hybrid OR was retrieved. A scoring system was used to evaluate the importance of the surgical and interventional components of a cerebrovascular procedure performed in the hybrid OR. The score of either component ranged from 1, 1.5, to 2 (1 = no role, 1.5 = supplementary or informative, 2 = important or therapeutic). The total score of a procedure was by multiplying two individual scores. Levels of necessity were classified into level A (important), level B (beneficial), and level C (replaceable). RESULTS: A total of 1027 cerebrovascular procedures were performed during this period: diagnostic angiography in 328, carotid artery stenting in 286, aneurysm coiling in 128, intra-operative DSA in 101, aspiration of ICH under image guidance in 79, intra-arterial thrombolysis/thrombectomy in 51, intracranial angioplasty/stenting in 30, hybrid surgery/serial procedures in 19, and rescue surgery during embolization in 5. According to the scoring system, hybrid surgery and serial procedures scored the highest points (2 × 2). The percentages distributed at each level: levels A (2.3%), B (17.5%), and C (80.2%). CONCLUSION: This study conveys a concept of what a hybrid OR equipped with robotic angiographic fluoroscopy system is capable of and its potential. For cerebrovascular diseases, hybrid OR exerts its value via hybrid surgery or avoiding patient transportation in serial procedures (level A), via providing real-time high-quality angiography and image guidance (level B), which constituted about 20% of the cases. The subspecialty of the group using the hybrid OR directly reflects on the number of procedures categorized in each level. In a hybrid OR, innovative treatment strategies for difficult-to-treat CVD can be developed.

A single-institution study of predisposing factors of patients with BAVMs to flow-related aneurysm.

BACKGROUND AND PURPOSE: The goal of this study was to assess the potential risk factors leading to flow-related aneurysm (FA) formation in patients with brain arteriovenous malformations (BAVMs) in Taiwanese. METHODS: We recruited 890 patients with BAVMs: 72 had FA(s) and 818 did not. Several factors were assessed including patient's age, gender, BAVM volume and location, and Spetzler-Martin grade. RESULTS: The 890 patients with BAVM had a mean age of 30 years (range: 2-84), mean BAVM volume of 10.6 mL (range: 0.13-91.4). BAVMs were ruptured in 42% of patients. Compared to BAVM patients without FAs, the 72 patients with FAs had older age (mean 41 yrs vs 31 yrs, p < 0.001); larger average BAVM volume (39.6 mL vs 16.1 mL, p < 0.001). No statistical significance in Spetzler-Martin grades (χ2 value = 8.687 and p = 0.122) was found in terms of formation of FA. FA demonstrated similar gender distribution and BAVM location distribution (the χ2-value was 0.242 and 0.812, respectively). CONCLUSION: Patients with older age and large BAVM volume are more prone to FA. Gender, BAVM location, and BAVM grade are not statistically significant predisposing factors for FA.

Verification of bleeding points in carotid blowout syndrome using guidewire manipulation.

PURPOSE: Carotid blowout syndrome (CBS) is a catastrophic complication of aggressive treatment of head and neck cancer. Early detection of bleeding points with embolization is a life-saving procedure; however, some bleeding points may be difficult to identify. Our aim was to determine whether guidewire manipulation (GWM) could be used to verify bleeding point locations in patients with CBS. METHODS: Of the 92 patients with CBS referred for embolization in a 5-year period, 14 men and one woman (mean age 58 years) had bleeding points at locations that could not be definitely determined. We used GWM to verify the presence of these bleeding points. We assessed the anatomy of the ruptured arteries, technical details of GWM, and the angiographic and clinical outcomes. RESULTS: Bleeding points were difficult to detect because of the presence of small arterial pouches (n = 6) or multiple small arterial pouches (n = 9) in the unilateral or bilateral carotid arteries. Bleeding point locations were accurately identified using GWM in the internal carotid artery (n = 7), carotid bulb (n = 4), or common carotid artery (n = 4). Balloon-assisted GWM was applied in one patient. Fiber coils (n = 15) and/or liquid adhesives (n = 2) were used to occlude the affected artery. Endovascular management was technically successful in all patients and resulted in immediate cessation of hemorrhage without recurrence in a mean 22-month clinical follow-up. CONCLUSION: GWM is a simple and effective method for verifying bleeding points in ruptured arteries and preventing erroneous occlusion by embolization.

Intraprocedural arterial perforation during neuroendovascular therapy: Preliminary result of a dual-trained endovascular neurosurgeon in the neurosurgical hybrid operating room.

BACKGROUND: Intraprocedural arterial perforation (IPAP) is a potentially dismal complication of neuroendovascular therapy with high mortality and morbidity rates. The management of IPAP with the techniques described has been well established, but rescue results from the dual-trained endovascular neurosurgeon in the neurosurgical hybrid operating room (OR) are rarely reported. Here, we report five cases of successful rescue of IPAP in the neurosurgical hybrid OR and compare them with other series. METHODS: Between December 2009 and December 2013, 146 intracranial neuroendovascular procedures were performed in the hybrid operating room of Taichung Veterans General Hospital. A total of five patients with IPAP were identified. Postoperative clinical outcome was evaluated by Glasgow Coma Scale scores and postoperative 3-month modified Rankin Scale. RESULTS: The causes of the IPAP were coil protrusion (n = 3), microcatheter perforation (n = 1), and microwire penetration (n = 1). Two cases involved emergent ruptured aneurysms, while three cases occurred during elective procedures. Salvage treatment with emergent external ventricular drainage (EVD) was applied in all five cases. The average time-to-first-EVD was 16.25 min, and the average time-to-patent-EVD was 32.5 min. Postoperative 3-month outcome was good recovery (mRS ≤ 2) in all five cases. The zero mortality rate in our series is the most encouraging result in the published literature. CONCLUSION: IPAP can be rescued successfully with an aggressive approach and quick conversion to backup surgery by a dual-trained endovascular neurosurgeon in the hybrid OR. The value of the hybrid OR in neuroendovascular therapy should be further investigated in the future.