Residual In-Stent Carotid Stenosis and Cigarette Smoking are Independent Predictors of Carotid Restenosis After Carotid Artery Stenting-Results from 738 Carotid Artery Stenting Procedures at a Single Center.

BACKGROUND AND OBJECTIVES: Carotid artery stenting (CAS) has become a viable alternative to carotid endarterectomy for the management of carotid stenosis. Our aim was to determine the rate of radiographic restenosis after CAS and clinical, radiographic, and procedural predictors of in-stent restenosis. METHODS: Our single-center, prospectively maintained database was retrospectively reviewed for CAS procedures performed in symptomatic and asymptomatic patients over 12 years (2010-2022). Baseline demographic data, procedural characteristics, and preprocedural and postprocedural radiographic and clinical details were noted. Baseline characteristics of patients with and without carotid restenosis were compared using the χ2 test for categorical variables and the Student t-test for continuous variables. Univariate and multivariate analyses were performed to determine risk factors associated with restenosis, defined as >70% on digital subtraction angiography. RESULTS: A total of 1017 consecutive CAS procedures were performed in 905 patients during the 12-year period, with 738 in 632 patients included in our study. Our cohort's overall restenosis rate was 17%, with a 14% restenosis rate at 2 years. On multivariate regression analysis, former or current smoking status (odds ratio [OR] = 2.3, 95% CI 1.2-4.1), plaque irregularity (OR 0.55, 95% CI 0.33-0.91), moderate (50.1%-75%) contralateral stenosis (OR 3.2, 95% CI 1.4-7.2), severe (75.1%-99.9%) contralateral stenosis (OR 2.8, 95% CI 1.3-6.0), and residual (>70%) in-stent stenosis after initial stenting (OR 433, 95% CI 80-2346) were significantly associated with carotid restenosis. Area under the curve for the multivariate regression model analysis was 0.78. Patients with <28.6% initial (residual) in-stent stenosis (45/517 cases) had a 9% restenosis rate, whereas those with >28.6% initial in-stent stenosis (77/221 cases) had a 35% restenosis rate. CONCLUSION: In this large, single-center study of carotid artery stenosis treated with CAS, residual in-stent carotid stenosis of approximately 30% and smoking status were independent predictors for restenosis. Maximizing treatment of initial stenosis and smoking cessation education are important steps in preventing future carotid restenosis.

Cerebral emboli detection and autonomous neuromonitoring using robotic transcranial Doppler with artificial intelligence for transcatheter aortic valve replacement with and without embolic protection devices: a pilot study.

BACKGROUND: Periprocedural ischemic stroke remains a serious complication in patients undergoing transcatheter aortic valve replacement (TAVR). We used a novel robotic transcranial Doppler (TCD) system equipped with artificial intelligence (AI) for real-time continuous intraoperative neuromonitoring during TAVR to establish the safety and potential validity of this tool in detecting cerebral emboli, report the quantity and distribution of high intensity transient signals (HITS) with and without cerebral protection, and correlate HITS occurrence with various procedural steps. METHODS: Consecutive patients undergoing TAVR procedures during which the robotic system was used between October 2021 and May 2022 were prospectively enrolled in this pilot study. The robotic TCD system included autonomous adjustment of the TCD probes and AI-assisted post-processing of HITS and other cerebral flow parameters. Basic demographics and procedural details were recorded. Continuous variables were analyzed by a two-sample Mann-Whitney t-test and categorical variables by a χ2 or Fisher test. RESULTS: Thirty-one patients were prospectively enrolled (mean age 79.9±7.6 years; 16 men (51.6%)). Mean aortic valve stenotic area was 0.7 cm2 and mean aortic-ventricular gradient was 43 mmHg (IQR 31.5-50 mmHg). Cerebral protection was used in 16 cases (51.6%). Significantly fewer emboli were observed in the protection group than in the non-protection group (mean 470.38 vs 693.33; p=0.01). Emboli counts during valve positioning and implantation were significantly different in the protection and non-protection groups (mean 249.92 and 387.5, respectively; p=0.01). One (4%) transient ischemic attack occurred post-procedurally in the non-protection group. CONCLUSION: We describe a novel real-time intraoperative neuromonitoring tool used in patients undergoing TAVR. Significantly fewer HITS were detected with protection. Valve positioning-implantation was the most significant stage for intraprocedural HITS.

Coiling Variations for Treatment of Ruptured Intracranial Aneurysms: A Meta-Analytical Comparison of Comaneci-, Stent-, and Balloon-Coiling Assistance Techniques.

BACKGROUND: Wide-necked aneurysms represent a challenge for treatment in the setting of acute subarachnoid hemorrhage. Stent-assisted coiling (SAC) and balloon-assisted coiling (BAC) are well-known techniques for treating wide-necked aneurysms. Comaneci-assisted coiling (CAC) is a newer technique involving temporary stent deployment to assist aneurysm coiling. We aim to present the first meta-analysis comparing these treatments of ruptured aneurysms. METHODS: Following PRISMA guidelines, PubMed and Embase databases were queried from earliest records to July 2022 for literature reporting SAC, BAC, or CAC of ruptured intracranial aneurysms. A meta-analysis of identified articles was performed. RESULTS: Of the 571 articles queried, 64 articles were included. One study reported BAC and SAC, 8 reported BAC, 52 reported SAC, and 3 reported CAC. These studies comprised 3153 patients with 3207 ruptured aneurysms treated with CAC (161 patients and aneurysms), BAC (330 patients and aneurysms), and SAC (2662 patients, 2716 aneurysms). Rates of periprocedural thromboembolic or hemorrhagic complications, overall or procedure-related mortality, immediate complete occlusion, retreatment, and length of angiographic follow-up did not differ significantly between SAC and BAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P = 0.01) complication rates were higher with BAC than CAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P < 0.0001) complication rates were higher with SAC than CAC. Complete aneurysm occlusion rates (P = 0.033) were higher with CAC than BAC. No significant differences were present in CAC versus BAC or SAC retreatment rates. CONCLUSIONS: CAC was associated with lower hemorrhagic and thromboembolic complication rates and demonstrated similar complete occlusion and residual retreatment rates to those for BAC and SAC.

Pretreatment and Posttreatment Factors Associated with Shunt-Dependent Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis.

BACKGROUND: Hydrocephalus is a common complication after aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to evaluate novel preoperative and postoperative risk factors for shunt-dependent hydrocephalus (SDHC) after aSAH via a systematic review and meta-analysis. METHODS: A systematic search was conducted using PubMed and Embase databases for studies pertaining to aSAH and SDHC. Articles were assessed by meta-analysis if the number of risk factors for SDHC was reported by >4 studies and could be extracted separately for patients who did or did not develop SDHC. RESULTS: Thirty-seven studies were included, comprising 12,667 patients with aSAH (SDHC 2214 vs. non-SDHC 10,453). In a primary analysis of 15 novel potential risk factors, 8 were identified to be significantly associated with increased prevalence of SDHC after aSAH, including high World Federation of Neurological Surgeons grades (odds ratio [OR], 2.43), hypertension (OR, 1.33), anterior cerebral artery (OR, 1.36), middle cerebral artery (OR, 0.65), and vertebrobasilar artery (2.21) involvement, decompressive craniectomy (OR, 3.27), delayed cerebral ischemia (OR, 1.65), and intracerebral hematoma (OR, 3.91). CONCLUSIONS: Several new factors associated with increased odds of developing SDHC after aSAH were found to be significant. By providing evidence-based risk factors for shunt dependency, we describe an identifiable list of preoperative and postoperative prognosticators that may influence how surgeons recognize, treat, and manage patients with aSAH at high risk for developing SDHC.

Salvage of Intraoperative Rupture of a Wide-Necked Middle Cerebral Artery Bifurcation Aneurysm: The Felt-Fenestrated Clipping Technique.

BACKGROUND: Intraoperative aneurysm rupture during microsurgical clipping can be managed with different salvage techniques. In an aneurysm with a very wide neck that is located at a bifurcation, repairing an iatrogenic tear can be challenging and carry the risk of branch occlusion and infarction. OBJECTIVE: To describe a variation of the cotton-clipping technique modified to better fit the bifurcation anatomy, which we call "felt-fenestrated clipping." METHODS: An illustrative case of intraoperative rupture of a wide-necked middle cerebral artery bifurcation aneurysm is presented. Radiological imaging, operative video, and technique illustration were obtained and prepared for this report. RESULTS: A middle-aged woman underwent microsurgical clipping of a wide-necked middle cerebral artery bifurcation aneurysm. A right-angle clip became dislodged from the clip applier and snapped across the aneurysm causing a small rupture at the base. This was later determined to be the result of improper placement of a standard clip onto a mini-clip applier. After a few salvage attempts, a small piece of Teflon felt was placed over the rupture site and held in place using a straight, fenestrated clip. Then, the right-angle clip was applied over the true neck of the aneurysm and the edge of the rupture site, covering the Teflon felt to obtain true hemostasis. CONCLUSION: We demonstrate a technically successful felt-fenestrated clipping technique for treatment of an intraoperative rupture not amenable to other salvage options. This technique is useful to achieve hemostasis while preserving branches in wide-necked bifurcation aneurysms.

Acute isolated posterior cerebral artery stroke treated with mechanical thrombectomy: A single-center experience and review of the literature.

BACKGROUND: Acute isolated posterior cerebral artery (PCA) occlusions account for 5-10% of all ischemic events. Due to peculiar patient presentation, the potential benefit of mechanical thrombectomy (MT) remains controversial. We evaluated the safety, feasibility, and effectiveness of MT in our patients and compared our results with the literature review conducted. METHODS: Charts were reviewed retrospectively for consecutive patients diagnosed with acute PCA stroke who underwent MT. Demographics, procedural, and follow-up details were noted. For the literature review, a systematic search of PubMed, MEDLINE, and EMBASE databases was conducted for the keywords "posterior cerebral artery" and "thrombectomy" for articles published between January 1, 2010 and June 30, 2021. Estimated rates for recanalization, favorable outcomes (modified Rankin Scale [mRS] score 0-2), symptomatic intracerebral hemorrhage (sICH), and mortality were extracted. RESULTS: Our cohort included 21 patients. Mean age was 71.2 years (standard deviation [SD] ± 10.2). Median National Institutes of Health Stroke Scale (NIHSS) presentation score was 9 (interquartile range [IQR] 5-15), with visual symptoms reported in 12(57.1%) patients. Overall, final modified thrombolysis in cerebral infarction (mTICI) 2b-3 was achieved in 17 patients (80.9%) with first-pass mTICI 2b-3 attained in 8 (38.1%). Postprocedure sICH occurred in 1 (4.8%) patient. Fifteen (71.4%) patients had a 0-2 mRS score at 90 days. Visual symptoms resolved in 10 of 12(83.3%) patients. Mortality occurred in 2 (9.5%) patients. For the systematic review, cohorts from 4 articles plus ours were included, totaling 222 patients. The estimated rate of successful recanalization was 85.25% (95% confidence interval[CI], 73.05%-97.45%), sICH was 3.60% (95% CI, 1.11%-6.09%), and mortality was 10.51% (95% CI, 5.88%-15.15%). CONCLUSION: The results of our series and systematic review indicate MT as a potentially safe and effective treatment modality for acute PCA stroke. These results also indicate that patient selection and assessment may be the key in obtaining favorable outcomes.

Not a trifecta: complementary use of carotid artery revascularization techniques in the era of hybrid neurosurgery.

OBJECTIVE: Carotid stenosis is currently treated by carotid endarterectomy (CEA), carotid artery stenting (CAS), or transcarotid artery revascularization (TCAR). This study sought to add to the literature by providing real-world data comparing the safety and effectiveness associated with the performance of these carotid revascularization techniques by dual-trained neurosurgeons. METHODS: The authors performed a retrospective review of carotid stenosis databases at two US centers. Patients treated by CEA, transfemoral CAS, or TCAR for atherosclerotic carotid artery disease were included. Clinical outcomes were compared at 30 days after the procedure. RESULTS: Seven hundred eighty patients were included (583 with CAS, 165 with CEA, and 32 with TCAR). Overall, 486 patients (62.3%) were men, and 393 (50.4%) had left-sided carotid stenosis. Most patients (n = 617, 79.1%) had symptomatic disease. Among the three treatment groups, there were no statistically significant differences with respect to 30-day ischemic events (CAS 3.8%, CEA 1.8%, TCAR 6.3%; p = 0.267) or 30-day mortality rates (CAS 3.6%, CEA 2.4%, TCAR 3.1%; p = 0.857). Male sex had significantly lower odds of 30-day transient ischemic attack (TIA) or stroke in both univariable (p = 0.024) and multivariable (p = 0.023) regression models. Increasing age had significantly higher odds of 30-day mortality on univariable (p = 0.006) and multivariable (p = 0.003) regression. Patients with the occurrence of 30-day TIA or stroke also had significantly higher odds of 30-day mortality on univariable (p < 0.001) and multivariable (p < 0.001) regression. CONCLUSIONS: This real-world experience reflects the current practice of hybrid neurosurgery at two high-volume tertiary care centers and suggests that all three treatment modalities have comparable safety and effectiveness if patients are properly selected.

Carotid Artery Stenting Using the Walrus Balloon Guide Catheter With Flow Reversal for Proximal Embolic Protection: Technical Description and Single-Center Case Series.

BACKGROUND: The use of modern transfemoral balloon guide catheters (BGC) for flow reversal during carotid artery stenting is scarcely described in the literature but represents a promising and efficient technique for embolic protection. OBJECTIVE: To describe a flow-reversal technique using the Walrus BGC (Q'Apel Medical Inc.) and report our center's experience. METHODS: We performed a retrospective analysis of data for consecutive patients aged 18 years or older who underwent elective carotid artery stenting with the use of flow reversal through the Walrus BGC between July 2020 and September 2021. Patient characteristics, procedural details, and clinical follow-up were evaluated. RESULTS: One hundred and five patients were included. Mean age was 69.8 ± 9.4 years, and 36 (34.3%) were women. The most common comorbidities were hyperlipidemia (76.2%) and hypertension (57.1%). Fifty-nine (56.2%) patients were symptomatic. Ninety-nine (94.3%) patients had stenosis ≥70%. Contralateral stenosis ≥50% was present in 44 patients (41.9%). Distal filters were used after flow reversal was established in 90 patients (85.7%). Angioplasty was performed in 85 patients (80.9%). Stenting was successful in 100% of cases. No periprocedural transient ischemic attacks (TIAs) or strokes occurred. Stroke occurred in 2 patients (1.9%) during the 30-day follow-up period, resulting in 1 (0.9%) death. CONCLUSION: In our experience, this technique was safe, feasible, and efficient, with 100% technical success and no periprocedural thromboembolic complications. More extensive studies are needed to establish the role of proximal protection with flow reversal using modern BGCs.

Volumetric resolution of chronic subdural hematomas treated with surgical evacuation versus middle meningeal artery embolization during immediate, early, and late follow up: propensity-score matched cohorts.

BACKGROUND: Literature on volumetric resolution and recurrence over time between surgical evacuation alone (SEA) and standalone middle meningeal artery embolization (MMAE) in comparable chronic subdural hematoma (cSDH) patients is limited. METHODS: A retrospective database analysis of cSDH patients managed with either SEA or MMAE was conducted. Propensity-score matching was performed for axial and coronal lengths, maximum diameter, and midline shift. Volumetric measurements at multiple time intervals and recurrence were compared between the groups. RESULTS: 48 matched hematoma pairs in patients with similar demographics, comorbidities, medications, and symptoms were obtained. Median volume was significantly lower at 24 hours in the SEA group (12.6 mL vs 52.7 mL, p<0.001) but not at remaining intervals. Median volume reduction was significantly greater in the SEA group at 24 hours (39.1 mL vs 8.8 mL in the MMAE group, p<0.001) and at 3-12 weeks (50.8 mL vs 23.7 mL, p<0.001), but not at remaining intervals. The SEA group had a significantly greater median hematoma resolution rate at 24 hours (39.1 mL/day vs 8.8 mL/day, p<0.001) and 3-12 weeks (1 mL/day vs 0.4 mL/day, p<0.001), but not at remaining intervals. Near-complete resolution at 3-12 weeks and 12-60 weeks was not significantly different between groups. Overall, the recurrence rate was significantly higher in the SEA group (22.9% vs 4.2%, p=0.01). CONCLUSIONS: In comparable cSDH patients, SEA resulted in better volumetric outcomes in immediate postoperative and early follow-up periods, as expected. However, this difference was not significant at more distant follow-up intervals. Furthermore, surgical patients experienced a significantly higher rate of recurrence.

Prone Transpsoas Lateral Lumbar Interbody Fusion for Degenerative Lumbar Spine Disease: Case Series With an Operative Video Using Fluoroscopy-Based Instrument Tracking Guidance.

BACKGROUND: Lateral lumbar interbody fusion has inherent limitations, such as the necessity to reposition the patient. To overcome this limitation, the prone transpsoas (PTP) approach for lateral lumbar interbody fusion has been developed. OBJECTIVE: To report clinical and radiographic outcome measures of a series of patients who underwent PTP at our hospital. METHODS: A retrospective chart review was conducted to identify patients who underwent PTP for degenerative lumbar spine disease between September 2019 and August 2021. A thorough analysis of clinical and radiographic outcome measures for these patients was conducted. RESULTS: Our search resulted in the identification of 15 consecutive patients. Four patients were operated using the assistance of fluoroscopy-based instrument tracking. Overall, the mean follow-up duration was 11.9 ± 7.9 months. Radiographically, the PTP approach resulted in significant postoperative improvement of lumbar lordosis ( P = .03) and pelvic incidence minus lumbar lordosis ( P < .005). No significant difference was found postoperatively in other regional sagittal alignment parameters, including pelvic tilt, sacral slope, or pelvic incidence. Clinically, the patients' Oswestry Disability Indices ( P = .002) and Short Form Survey-12 Physical Scores improved significantly ( P = .01). The estimated mean blood loss for patients who underwent the PTP procedure was 137.7 ± 96.4 mL, the mean operative time was 212.5 ± 77.1 minutes, and the mean hospital stay was 2.7 ± 1.4 days. One patient each had superficial wound infection, transient paralytic ileus, transient pulmonary embolism, transient urinary retention, or required revision lumbar surgery. CONCLUSION: This study demonstrates that the PTP approach is associated with significant improvement in radiographic and clinical outcomes.

Statins versus Nonstatin Use in Patients with Chronic Subdural Hematomas Treated with Middle Meningeal Artery Embolization Alone - A Single-Center Experience.

BACKGROUND: Statins have been reported to reduce the rates of recurrence and improve the resolution of chronic subdural hematomas (cSDHs) treated surgically or conservatively. No studies have investigated the effect of statins in patients treated with middle meningeal artery embolization. METHODS: We performed a retrospective search of our cSDH database to identify patients treated with middle meningeal artery embolization alone. Only patients with at least 1 noncontrast computed tomography scan obtained 3-12 weeks after embolization were included. Hematoma volumes were measured at baseline and last noncontrast computed tomography available. The volumes, volume reduction, speed of resolution, and recurrence were compared between patients already receiving statin therapy when admitted and those who were not. RESULTS: Forty-six patients with 50 cSDHs were included (statins, 17 patients with 18 cSDHs vs. nonstatins, 29 patients with 32 cSDHs). The statin group had a significantly higher rate of hyperlipidemia (statin, 64.7% vs. nonstatin, 31%, P = 0.03) but similar demographics, remaining comorbidities, medications, and hematoma thickness, axial and coronal lengths, and baseline volumes. The time between procedure and last noncontrast computed tomography scan was similar between groups. There were no differences between the groups regarding volume reduction, final volume, speed of resolution, complete resolution, and recurrence. CONCLUSIONS: Patients treated with middle meningeal artery embolization alone who were on statin therapy had no differences in cSDH resolution or recurrence compared to those who were not on statin therapy. It is possible that the anti-inflammatory effects of statins may not be relevant when supply to the dura is interrupted by treatment with embolization.

The Effect of Statins on the Recurrence of Chronic Subdural Hematomas: A Systematic Review and Meta-Analysis.

BACKGROUND: Statins have been proposed to improve the resolution of chronic subdural hematoma (cSDH), with conflicting results likely due to underpowered analysis or confounding factors, such as the use of antithrombotic medication. We performed a systematic literature review and meta-analysis to better elucidate the effect of statin therapy on cSDH recurrence. METHODS: We performed a comprehensive search of PubMed, MEDLINE, and Embase databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were included if the number of recurrences requiring surgical evacuation or leading to neurological deterioration was reported and could be extracted separately for patients who did or did not receive statin therapy. RESULTS: Seven studies were included, comprising 1359 cSDH patients (statin therapy, 449 vs. non-statin therapy, 910). Age was not different between groups (P = 0.548). The proportion of men was significantly different (statin, 80.1% vs. non-statin, 74.7%; P = 0.02). Use of antithrombotic medication was significantly higher (P = 0.005) in the statin group (11.7%) than in the non-statin group (7.3%). The statin group had a non-significant lower odds of recurrence (odds ratio 0.80, 95% confidence interval 0.35-1.81). In an exploratory data analysis of 4 studies without a difference between groups in antithrombotic medication use, the statin group had significantly lower odds of recurrence (odds ratio 0.29, 95% confidence interval 0.17-0.50). CONCLUSIONS: Overall, we found that statin use did not result in lower odds of cSDH recurrence, likely due to a dilution caused by the higher rate of patients on antithrombotic medications in the statin group.