Faculty Bibliography

OBJECTIVE:Middle meningeal artery (MMA) embolization may be an effective means of inhibiting neovascularization of the subdural capsular membrane and preventing hematoma maintenance. We sought to better understand how the MMA may affect subdural hematoma physiology and how this process may be modified by embolization. METHODS:A retrospective review was done. We studied 27 patients with 29 SDHs who underwent MMA embolization from July 2018 to May 2019. Eight of these patients had post-embolization DynaCT imaging and were included. RESULTS:Average patient age was 75 years old. Baseline non-contrast head CT showed the presence of a hematoma membrane in all 8 patients. Post-embolization DynaCTs in all patients demonstrated enhancement of all four components (dura, capsular membrane, septations, and subdural hematoma fluid). All patients had a minimum 60-day imaging and clinical follow-up. There was an average 87% decrease in SDH volume at last follow-up compared to baseline. There was a significant difference between the average baseline and average last follow-up SDH volume (paired t-test, p < 0.0001) in all patients. Average last follow-up scan was 89 days (range 61-122 days) from the date of procedure. No patient experienced post-embolization complications, subsequent SDH drainage, or mortality. CONCLUSIONS:Our data lends support to the theory of contiguous vascular networks between the MMA and SDH membranes. Targeting these leaky vascular networks may remove the source of hematoma accumulation. This adds to the pathophysiological understanding of the disease and suggests potential insight into the mechanism of action of MMA embolization.

Flow diverters (FDs) have changed the management of brain aneurysms; not only for complex aneurysms (giant, fusiform and blister) refractory to conventional therapies, but also for unruptured lesions previously managed by traditional surgical or coil-based endovascular methods. Since 2011 when the PipelineTM Embolization Device (Medtronic) was cleared by the Food and Drug Administration for adults with large or giant wide-neck intracranial aneurysms of the internal carotid artery proximal to the posterior communicating segment, the role of flow diversion for aneurysm treatment has expanded-supported by favorably low complication and high cure rates compared with alternative treatments. Here we review the key clinical trials and the long term outcomes that have demonstrated safety and efficacy of minimized porosity endoluminal devices in the treatment of cerebral aneurysms.

BACKGROUND:The supraorbital craniotomy (SOC) is classically performed through a skin incision in the patient's eyebrow. A variant with a skin incision in the patient's eyelid has become increasingly popular in recent years. OBJECTIVE:To compare the transpalpebral and the transciliary variants of the SOC with regard to their potential role in aneurysm surgery. METHODS:We carried out cadaveric dissections and virtual craniotomies on computerized tomography datasets. The skin incision, the craniotomy location and size, the working angles, and the achievable exposure of neurovascular structures were assessed and compared for both variants of the SOC. RESULTS:The skin incision measured 4 cm for the transpalpebral and 3 cm for the transciliary variant. The skin could be retracted 1.5 cm upward from the lower edge of the orbital rim with the transpalpebral and 2.5 cm upward with the transciliary variant. The craniotomy size was 2.5 × 1.5 cm for both variants, given that the transpalpebral variant included an orbital osteotomy. The bony opening in the transpalpebral variant was 1 cm more caudal; this restricted the craniocaudal working angles and, thereby, limited the achievable exposure of neurovascular structures in the paraclinoid area and along the sphenoid ridge. CONCLUSION/CONCLUSIONS:If the orbital rim and the anterior aspect of the orbital roof are removed, then the transpalpebral variant of the SOC enables a bony opening that is just as large as that of the transciliary variant. Nonetheless, the more caudal location of the bony opening alters the available working angles and may impede exposure of key structures during aneurysm surgery.

Neuroendovascular surgery and interventional neuroradiology both describe the catheter-based (most often) endovascular diagnosis and treatment of vascular lesions affecting the brain and spinal cord. This article traces the evolution of these techniques and their current role as the dominant and frequently standard approach for many of these conditions. The article also discusses the important changes that have been brought to bear on open cerebrovascular neurosurgery by neuroendovascular surgery and their effects on resident and fellow training and describes new concepts for clinical care.

Introduction The 5 seminal mechanical thrombectomy (MT) trials had a median age of 68 years. Though some of these trials included nonagenarians, there is little data on their outcomes. We aimed to compare the procedural, discharge outcomes and complications, of MT for acute ischemic stroke (AIS) in nonagenarians versus younger patients(<=69) Methods Patients with AIS admitted to two comprehensive stroke centers were enrolled prospectively in a registry. Rates of MT were compared between nonagenarians vs <=69. Among those who underwent MT, procedural outcomes, complications, and discharge disposition were compared in propensity scorematched groups (matched for NIHSS, pre-stroke mRS, IV-tPA administration and T IG grade>=2b) of nonagenarians to patients<=69. Good discharge disposition was defined as a discharge to home/acute rehabilitation. Results Of the 3010 AIS patients, 46/297 (16%) nonagenarians underwent MT compared to 159/1337 (12%) patients <=69 (P=0.091) with TICI>=2b of 89% vs 94%; p=0.238 respectively. 78 patients (N=39 >=90, N=39 <69) were propensity score-matched with a median admission NIHSS of 22 and 19, and median ASPECTS of 9 and 9, respectively (both P>0.05). Those <69 more often had Ml occlusions than nonagenarians (84% vs 50%, P=0.035), whereas ICA (10% vs 13%, p=0.76), and M2 (21% vs 43%, p=0.19) occlusions were similar between the two groups. Time to groin puncture (100+/-65 vs 76+/-34; p=0.124), revascularization time (134+/-72 vs 110+/-54; p=0.145), complication rates (0 vs 5.1%; p=0.494) and inhospital deaths (11% vs 24%; p=0.155) were similar among the two groups. 44% of nonagenarians had good discharge disposition, compared to 51% of patients <69 years (p=0.650) Conclusions We present one of the largest series of MT among nonagenarians with 89% successful recanalization rates. In propensity score analysis almost half of nonagenarians (44%) were discharged to home/rehab, which is comparable to a younger cohort (51%). Aggressive management is warranted in the oldest of the old

BACKGROUND:There is limited data on predictors of symptomatic intracranial haemorrhage (sICH) in patients who underwent mechanical thrombectomy. In this study, we aim to determine those predictors with external validation. METHODS:and t tests to identify independent predictors of sICH with p<0.1. Significant variables were then combined in a multivariate logistic regression model to derive an sICH prediction score. This score was then validated using data from the Blood Pressure After Endovascular Treatment multicentre prospective registry. RESULTS:We identified 578 patients with acute ischaemic stroke who received thrombectomy, 19 had sICH (3.3%). Predictive factors of sICH were: thrombolysis in cerebral ischaemia (TICI) score, Alberta stroke program early CT score (ASPECTS), and glucose level, and from these predictors, we derived the weighted TICI-ASPECTS-glucose (TAG) score, which was associated with sICH in the derivation (OR per unit increase 1.98, 95% CI 1.48 to 2.66, p<0.001, area under curve ((AUC)=0.79) and validation (OR per unit increase 1.48, 95% CI 1.22 to 1.79, p<0.001, AUC=0.69) cohorts. CONCLUSION/CONCLUSIONS:High TAG scores are associated with sICH in patients receiving mechanical thrombectomy. Larger studies are needed to validate this scoring system and test strategies to reduce sICH risk and make thrombectomy safer in patients with elevated TAG scores.

Anatomical vessel obstacles such as an intracranial stenosis in stroke are challenging and may lead to delayed clot access for thrombectomy. We describe a simple and effective technique to overcome the step-off between the intermediate catheter and an intracranial vessel stenosis during thrombectomy. The patient presented with acute embolic left middle cerebral artery occlusion and a favorable penumbral pattern. Clot access was made challenging by focal stenosis in the ipsilateral cavernous segment. The balloon-assisted tracking technique was effective in traversing the step-off to enable TICI 3 aspiration thrombectomy. This simple and effective technique should be kept in mind during stroke procedures where a proximal stenotic obstacle complicates access to the site of occlusion.

OBJECTIVEA systematic analysis on the utility of prophylactic antibiotics for neuroendovascular procedures has not been performed. At the authors' institution there is a unique setup to address this question, with some attending physicians using prophylactic antibiotics (cefazolin or vancomycin) for all of their neurointerventions while others generally do not.METHODSThe authors performed a retrospective review of the last 549 neurointerventional procedures in 484 patients at Tisch Hospital, NYU Langone Medical Center. Clinical and radiological data were collected for analysis, including presence of prophylactic antibiotic use, local or systemic infection, infection laboratory values, and treatment. Overall, 306 aneurysms, 117 arteriovenous malformations/arteriovenous fistulas, 86 tumors, and 40 vessel stenosis/dissections were treated with coiling (n = 109), Pipeline embolization device (n = 197), embolization (n = 203), or stenting (n = 40).RESULTSAntibiotic prophylaxis was used in 265 of 549 cases (48%). There was no significant difference between patients with or without antibiotic prophylaxis in sex (p = 0.48), presence of multiple interventions (p = 0.67), diseases treated (p = 0.11), or intervention device placed (p = 0.55). The mean age of patients in the antibiotic prophylaxis group (53.4 years) was significantly lower than that of the patients without prophylaxis (57.1 years; p = 0.014). Two mild local groin infections (0.36%) and no systemic infections (0%) were identified in this cohort, with one case in each group (1/265 [0.38%] vs 1/284 [0.35%]). Both patients recovered completely with local drainage (n = 1) and oral antibiotic treatment (n = 1).CONCLUSIONSThe risk of infection associated with endovascular neurointerventions with or without prophylactic antibiotic use was very low in this cohort. The data suggest that the routine use of antibiotic prophylaxis seems unnecessary and that to prevent antibiotic resistance and reduce costs antibiotic prophylaxis should be reserved for selected patients deemed to be at increased infection risk.