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.

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.

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.

Pre- and Post-Treatment Factors Associated with Shunt-Dependent Hydrocephalus after Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

INTRODUCTION

Hydrocephalus is a common complication following aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to evaluate novel pre- 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 were reported by greater than 4 studies and could be extracted separately for patients who did or did not develop SDHC.

RESULTS

37 studies were included, comprising 12,667 aSAH patients (SDHC 2,214 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 (WFNS) grades (odds ratio (OR) 2.43), hypertension (OR 1.33), anterior cerebral artery (ACA) (OR 1.36), middle cerebral artery (MCA) (OR 0.65), and vertebrobasilar artery (VBA) (2.21) involvement, decompressive craniectomy (DC) (OR 3.27), delayed cerebral ischemia (DCI) (OR 1.65), and intracerebral hematoma (ICH) (OR 3.91).

CONCLUSIONS

Several new factors associated with increased odds of developing SDHC following aSAH were found to be significant. By providing evidence-based risk factors for shunt dependency, we describe an identifiable list of pre- and postoperative prognosticators that may influence how surgeons recognize, treat, and manage aSAH patients at high risk for developing SDHC.

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.

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.

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.

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.

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 &lt; .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.

Abstract TP76: The Impact Of Registries In Stroke Literature

Introduction: Registries represent a main source of data to the advances in medical literature. In stroke medicine, they serve as key points of discussion and elaboration for future clinical trials, as well as evaluation tools for several treatment modalities in different patient populations. We performed an analysis of recent stroke registries to evaluate their impact in literature.

Methods: We performed PubMed and Google Scholar search using keywords with Boolean operators to identify studies deriving from stroke registries between January 2000 and June 2021. All registries identified were further characterized regarding study design, sample size, number of centers, number of peer reviewed articles or conference abstracts originating from it, with their respective number of citations and impact factor of journals.

Results: A total of 51 registries were identified, comprising 43584 patients. Forty-three (84.3%) were prospective. Forty-five (88.2%) were multicenter. Sixteen (31.4%) focused in a specific device for mechanical thrombectomy. Twenty-seven (52.9%) were registered on clinicaltrials.gov. The most participating countries were United States in 16 (31.4%) and Germany in 8 (15.7%). Twenty-seven (52.9%) registries originated a total of 295 peer-reviewed articles, 6841 citations and a sum of impact factors of 1282.8. The median impact factor of journals publishing articles from registries was 5.51 (interquartile range, 3.27-7.91). The median number of citations per article was 13 (interquartile range, 4-37). Between registered and unregistered registries, there was no significant difference in the median number of publications (P=0.08), citations (P=0.158) or impact factor (P=0.124). Between registries specific and unspecific to a certain device, there was no significant difference in median number of publications (P=1.67), citations (P=0.631) or impact factor (P=0.509).

Conclusions: Stroke registries provide a meaningful data source for literature regardless of registration or specificity to a certain device, and represent a key mechanism in the advances of stroke care. Contribution to stroke registries are key mechanism to elucidate clinical questions that require large sample size and should be incentivized.