Adeel Ilyas

Endovascular Mechanical Thrombectomy for Acute Ischemic Stroke Under General Anesthesia Versus Conscious Sedation: A Systematic Review and Meta-Analysis

BACKGROUNDnEndovascular mechanical thrombectomy (EMT) is the standard of care for eligible patients presenting with anterior circulation acute ischemic stroke (AIS) due to emergent large vessel occlusion (ELVO). The aim of this systematic review and meta-analysis is to compare the outcomes between patients undergoing general anesthesia (GA) versus conscious sedation (CS) for these procedures.nnnMETHODSnA literature review was performed to identify studies reporting the EMT outcomes of AIS patients who underwent GA or CS for the procedure. Baseline, treatment, and outcomes data were analyzed. Good outcome was defined as a modified Rankin Scale score of 0-2 at 3 months, and successful reperfusion was defined as modified thrombolysis in cerebral infarction grade of 2b-3.nnnRESULTSnNine studies, comprising a total of 1379 patients treated with GA (nxa0= 761) or CS (nxa0= 618) for EMT, were included. Based on pooled data, GA achieved good outcome in 35% and successful reperfusion in 81%, whereas CS achieved good outcome in 41% and successful reperfusion in 75%. Meta-analyses showed no significant differences in the rates of good outcome (Pxa0= 0.51) or successful reperfusion (Pxa0= 0.39) between the GA and CS groups. The rates of pneumonia were significantly higher in the GA group (21% vs. 11%; Pxa0= 0.01).nnnCONCLUSIONSnThe use of either GA or CS during EMT for patients with anterior circulation acute ELVO does not yield significantly different rates of functional independence at 3 months.

Seizure Outcomes After Radiosurgery for Cerebral Arteriovenous Malformations: An Updated Systematic Review and Meta-Analysis

OBJECTIVEnThe seizure outcomes for patients with brain arteriovenous malformations (AVM) who undergo intervention with stereotactic radiosurgery (SRS) are incompletely understood. We sought to determine, in a systematic review and meta-analysis, the rates of seizure control after SRS for patients with AVM-associated seizures and identify predictive factors.nnnMETHODSnWe performed a systematic review of PubMed and MEDLINE databases from January 1987 to January 2018, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting post-SRS outcomes data for ≥5 patients with AVM-associated seizures were included. The seizure outcomes and factors associated with seizure freedom were evaluated using meta-analysis.nnnRESULTSnA total of 27 studies, comprising 4826 patients, met the inclusion criteria for analysis. One or more seizures occurred in 1456 of 4826 patients (34.7% [26.0-43.9%]), and the mean follow-up was 48 ± 7 months. Seizure control (seizure freedom or seizure improvement) was achieved in 910 of 1312 patients (73.1% [66.9-78.9%]). Seizure freedom was achieved in 597 of 1245 patients (55.7% [44.5-66.6%]). Of 259 patients with seizure freedom, cessation of antiepileptic drugs was achieved in 175 patients (67.3% [46.3-85.1%]). AVM obliteration (odds ratio [OR] 4.61; Pxa0<xa00.001), shorter seizure duration (OR 6.80; Pxa0<xa00.001), generalized seizure type (OR 2.27; Pxa0= 0.007), and previous AVM hemorrhage (OR 5.10; P < 0.001) were significantly associated with seizure freedom.nnnCONCLUSIONSnSRS affords seizure control to the majority of patients with AVM-associated seizures, and approximately two thirds of those with seizure freedom are able cease anticonvulsants. Nidal obliteration appears to improve the likelihood of seizure freedom, and thus remains the primary goal of intervention with SRS.

Safety of Running Two Rooms: A Systematic Review and Meta-Analysis of Overlapping Neurosurgical Procedures

OBJECTIVEnOverlapping surgery, a long-standing practice within academic neurosurgery centers nationwide, has recently come under scrutiny from the government and media as potentially harmful to patients. Therefore, the objective of this systematic review and meta-analysis is to determine the safety of overlapping neurosurgical procedures.nnnMETHODSnThe authors performed a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A review of PubMed and Medline databases was undertaken with the search phrase overlapping surgery AND neurosurgery AND outcomes. Data regarding patient demographics, type of neurosurgical procedure, outcomes, and complications were extracted from each study. The principle summary measure was odds ratio (OR) of the association of overlapping versus non-overlapping surgery with outcomes.nnnRESULTSnThe literature search yielded a total of 36 studies, of which 5 studies met inclusion criteria and were included in this study. These studies included a total of 25,764 patients undergoing neurosurgical procedures. Overlapping surgery was associated with an increased likelihood of being discharged home (OR, 1.32; 95% confidence interval [CI], 1.20-1.44; P < 0.001) and a reduced 30-day unexpected return to the operating room (OR, 0.79; 95% CI, 0.72-0.87; P < 0.001). Overlapping surgery did not significantly affect OR of length of surgery, 30-day mortality, or 30-day readmission.nnnCONCLUSIONSnOverlapping neurosurgical procedures were not associated with worse patient outcomes. In addition, prospective studies are needed to assess the safety overlapping procedures.

Antiplatelet Medication Reversal Strategies in Operative Intracranial Hemorrhage: A Survey of Practicing Neurosurgeons

BACKGROUNDnAntiplatelet therapy is common and complicates operative management of acute intracranial hemorrhage. Few data exist to guide antiplatelet reversal strategies.nnnMETHODSnAn online survey detailing antiplatelet reversal strategies in patients presenting with acute operative intracranial hemorrhage (subdural hematoma, epidural hematoma, and intracerebral hemorrhage) was distributed to board-certified neurosurgeons in North America.nnnRESULTSnFrom 2782 functional e-mail addresses, there were 493 (17.7%) responses to question 1 and 429 (15.4%) completed surveys. Most respondents chose to perform no additional laboratory testing before surgical intervention, regardless of hemorrhage type. The most common antiplatelet reversal strategy in the presence of aspirin was platelet transfusion (subdural hematoma and intracerebral hemorrhage) or no intervention (epidural hematoma). The most common antiplatelet reversal strategy in the presence of an adenosine diphosphate antagonist or dual antiplatelet therapy was platelet transfusion or platelet transfusion with desmopressin acetate administration. There was a statistically significant difference in management strategy depending on the antiplatelet therapy (P < 0.001).nnnCONCLUSIONSnWhen patients on antiplatelet medication present with operative intracranial hemorrhage, the majority of neurosurgeons do not perform qualitative platelet testing. Antiplatelet reversal strategies are significantly influenced by the antiplatelet therapy with more aggressive reversal strategies employed in the presence of ADP antagonists.

Magnetic resonance–guided, high-intensity focused ultrasound sonolysis: potential applications for stroke

Stroke is one of the leading causes of death worldwide and a significant source of long-term morbidity. Unfortunately, a substantial number of stroke patients either are ineligible or do not significantly benefit from contemporary medical and interventional therapies. To address this void, investigators recently made technological advances to render transcranial MR-guided, high-intensity focused ultrasound (MRg-HIFU) sonolysis a potential therapeutic option for both acute ischemic stroke (AIS)-as an alternative for patients with emergent large-vessel occlusion (ELVO) who are ineligible for endovascular mechanical thrombectomy (EMT) or as salvage therapy for patients in whom EMT fails-and intracerebral hemorrhage (ICH)-as a neoadjuvant means of clot lysis prior to surgical evacuation. Herein, the authors review the technological principles behind MRg-HIFU sonolysis, its results in in vitro and in vivo stroke models, and its potential clinical applications. As a noninvasive transcranial technique that affords rapid clot lysis, MRg-HIFU thrombolysis may develop into a therapeutic option for patients with AIS or ICH. However, additional studies of transcranial MRg-HIFU are necessary to ascertain the merit of this treatment approach for thrombolysis in both AIS and ICH, as well as its technical limitations and risks.

Microsurgery Versus Stereotactic Radiosurgery for Brain Arteriovenous Malformations: A Matched Cohort Study

BACKGROUNDnMicrosurgery (MS) and stereotactic radiosurgery (SRS) remain the preferred interventions for the curative treatment of brain arteriovenous malformations (AVM), but their relative efficacy remains incompletely defined.nnnOBJECTIVEnTo compare the outcomes of MS to SRS for AVMs through a retrospective, matched cohort study.nnnMETHODSnWe evaluated institutional databases of AVM patients who underwent MS and SRS. MS-treated patients were matched, in a 1:1 ratio based on patient and AVM characteristics, to SRS-treated patients. Statistical analyses were performed to compare outcomes data between the 2 cohorts. The primary outcome was defined as AVM obliteration without a new permanent neurological deficit.nnnRESULTSnThe matched MS and SRS cohorts were each comprised of 59 patients. Both radiological (85 vs 11 mo; Pxa0<xa0.001) and clinical (92 vs 12 mo; Pxa0<xa0.001) follow-up were significantly longer for the SRS cohort. The primary outcome was achieved in 69% of each cohort. The MS cohort had a significantly higher obliteration rate (98% vs 72%; P = .001), but also had a significantly higher rate of new permanent deficit (31% vs 10%; P = .011). The posttreatment hemorrhage rate was significantly higher for the SRS cohort (10% for SRS vs 0% for MS; P = .027). In subgroup analyses of ruptured and unruptured AVMs, no significant differences between the primary outcomes were observed.nnnCONCLUSIONnFor patients with comparable AVMs, MS and SRS afford similar rates of deficit-free obliteration. Nidal obliteration is more frequently achieved with MS, but this intervention also incurs a greater risk of new permanent neurological deficit.

Automated detection of mesial temporal and temporoperisylvian seizures in the anterior thalamic nucleus

BACKGROUND AND PURPOSEnFocal seizures can arise from coordinated activity across large-scale epileptic networks and propagate to regions that are not functionally altered but are recruited by epileptiform discharges. In preclinical models of focal epilepsy, the thalamus is recruited by cortical onset seizures, but it remains to be demonstrated in clinical studies. In this pilot study, the authors investigate whether seizures with onset within and outside the mesial temporal structures are detected in the anterior thalamus (ATN).nnnMETHODSnAfter written consent, three subjects with suspected temporal lobe epilepsy undergoing stereotactic electrode implantation were recruited prospectively for thalamocortical depth EEG recordings. Three seizure detection metrics (line length-LL, Laplace operator-Lap; Teager energy-TE) were studied within the seizure onset zone and ATN.nnnRESULTSnThe LL, Lap, and TE metrics detected 40 (95%) seizures each in the ATN before the behavioral manifestation. Rates of detection in the seizure onset zone were 40 (95%), 42 (100%), and 41 (98%), respectively. The mean detection latency in ATN from SOZ ranged from 0.25 to 5.17u2009s. Seizures were localized to amygdala-hippocampus, temporal pole, anterior insula and superior temporal gyrus.nnnCONCLUSIONSnThe pilot study demonstrates that seizures in mesial temporal and temporal-plus epilepsies (i.e., temporoperisylvian) can be detected reliably in the ATN. Further studies are needed to validate these findings.

SMART coils for intracranial aneurysm embolization: Initial outcomes

OBJECTIVESnEndovascular technology for the treatment of intracranial aneurysms continues to rapidly evolve. The SMART coil (Penumbra Inc., Alameda, CA, USA) is a novel microcoil designed to enhance deliverability. The aim of this single-center, retrospective cohort study is to assess the initial outcomes after aneurysm embolization using SMART coils.nnnPATIENTS AND METHODSnWe reviewed consecutive patients with intracranial aneurysms who underwent endovascular embolization using SMART coils from June 2016 to January 2017. Baseline and initial outcomes data were analyzed.nnnRESULTSnThe study cohort was comprised of 32 patients with 33 aneurysms. The mean age was 55.8 years. The majority (85%) of aneurysms were located in the anterior circulation. The mean aneurysm maximum diameter and neck width were 6.0mm and 3.1mm, respectively. Dome irregularity and fusiform aneurysm morphology were noted in 33% and 9% of aneurysms, respectively, and 15% presented with subarachnoid hemorrhage. No serious procedural complications occurred, including microcatheter prolapse, intraprocedural aneurysm rupture, or thromboembolism. Device malfunction occurred in one case (3%). The mean packing density was 25%, and the degree of immediate post-embolization aneurysm occlusion was a modified Raymond-Roy grade I, II, IIIa, and IIIb in 48%, 27%, 18%, and 6%, respectively.nnnCONCLUSIONnOur preliminary findings suggest that the SMART coil has a favorable initial risk to benefit profile for the embolization of appropriately selected aneurysms. Additional studies of larger cohorts are necessary to determine the mid-term and long-term clinical and angiographic outcomes of aneurysm patients treated with the SMART coil.

Dynamics of seizure-induced behavioral and autonomic arousal

PurposeArousal is the most primitive, powerful instinct with survival benefit present in all vertebrates. Even though the arousal systems are classically viewed as “ascending” brainstem phenomena, there is a “descending” cortical feedback system that maintains consciousness. In this study, we provide electrophysiological confirmation that seizures localized to the anterior cingulum can behaviorally manifest as paroxysms of arousal from sleep.MethodsTemporal dynamics of arousal induced by anterior cingulate seizures were analyzed by using multiple modalities including stereoelectroencephalography (phase lag index and phase amplitude coupling), lead-1 ECG (point-process heart rate variability analysis) and diffusion tractography (DTI).ResultsThe ictal arousal was associated with an increase in synchronization in the alpha band and an increase in local theta or alpha-gamma phase-amplitude coupling. In comparison to seizures that lacked clinical manifestations, ictal arousal was associated with an increase in heart rate but not heart rate variability. Finally, DTI demonstrated degeneration in white fiber tracts passing between the anterior cingulum and anterior thalamus ipsilateral to the epileptogenic cortex. The patient underwent resection of the anterior cingulum, and histopathology confirmed focal cortical dysplasia type II.ConclusionAnterior cingulate seizures inducing behavioral arousal have identifiable autonomic and EEG signatures.