Faculty Bibliography

Mechanical disorders of the cervicocerebral circulation (MDCC) are conditions in which neurological symptoms result from a disturbance of cerebral blood flow attributable to external mechanical forces exerted on extracranial blood vessels by adjacent musculoskeletal structures during head movement that is presumably within a physiological range. The disease spectrum includes bow hunter's syndrome, carotid-type Eagle syndrome, and various dynamic venous compression syndromes. These conditions have distinct phenotypes in children which differ from those expressed in older adults. In contemporary practice, recognition and diagnostic evaluation is the domain of the neuroendovascular specialist. The diagnostic evaluation of MDCC involves significant technical nuance that can be critical to directing appropriate management, particularly in children. This report aims to provide a comprehensive overview of the pathophysiology, anatomical patterns, diagnosis, and treatment for the full spectrum of MDCC that is commonly encountered in clinical practice.

BACKGROUND AND PURPOSE/OBJECTIVE:Successful post-flow-diverter endoluminal reconstruction is widely believed to require endothelial overgrowth of the aneurysmal inflow zone. However, endothelialization/neointimal overgrowth is a complex process, over which we currently have very limited influence. Less emphasized is vascular remodeling of the target arterial segment, the dynamic response of the vessel to flow-diverter implantation. This process is distinct from flow modifications in covered branches. It appears that basic angiographic methods allow simple and useful observations. The purpose of this article was to quantitatively evaluate observable postimplantation changes in target vessels following deployment of Pipeline endoluminal constructs. MATERIALS AND METHODS/METHODS:One hundred consecutive adults with unruptured, previously untreated, nondissecting aneurysms treated with the Pipeline Embolization Device with Shield Technology and the availability of follow-up conventional angiography were studied with 2D DSA imaging. Target vessel size; Pipeline Embolization Device diameter; endothelial thickness; and various demographic, antiplatelet, and device-related parameters were recorded and analyzed. RESULTS:The thickness of neointimal overgrowth (mean, 0.3 [SD, 0.1] mm; range, 0.1-0.7 mm) is inversely correlated with age and is independent of vessel size, smoking status, sex, and degree of platelet inhibition. The decrease in lumen diameter caused by neointimal overgrowth, however, appears counteracted by outward remodeling (dilation) of the target arterial segment. This leads to an increase in the diameter with a corresponding decrease in length (foreshortening) of the implanted Pipeline Embolization Device. This physiologic remodeling process affects optimally implanted devices and is not a consequence of stretching, device migration, vasospasm, and so forth. A direct, linear, statistically significant relationship exists between the degree of observed outward remodeling and the diameter of the implanted Pipeline Embolization Device relative to the target vessel. Overall, remodeled arterial diameters were reduced by 15% (SD, 10%) relative to baseline and followed a normal distribution. Clinically relevant stenosis was not observed. CONCLUSIONS:Vessel healing involves both outward remodeling and neointimal overgrowth. Judicial oversizing could be useful in specific settings to counter the reduction in lumen diameter due to postimplant neointimal overgrowth; however, this overszing needs to be balanced against the decrease in metal coverage accompanying the use of oversized devices. Similar analysis for other devices is essential.

BACKGROUND:Direct puncture of the superior ophthalmic vein (SOV) is an alternative approach to traversing the inferior petrosal sinus for embolization of carotid cavernous fistulas (CCFs). OBJECTIVE:To analyze direct SOV puncture for the treatment of CCFs and review the literature. METHODS:All patients at a single center, treated for a CCF with direct SOV cannulation between January 1, 2000, and December 31, 2020, were retrospectively analyzed. An additional review of the literature for all case series for direct puncture of the SOV for treatment of CCF was performed. RESULTS:During the 21-year study period, direct cannulation of the SOV for treatment of a CCF was attempted for 19 patients, with the procedure aborted for one patient because of an inability to navigate the wire into the distal aspect of the cavernous sinus. In 18 patients with direct SOV CCF treatment, 1 experienced a minor complication with an asymptomatic postoperative hemorrhage. Angiographic cure and improvement of symptoms were achieved in 17 patients with a mean (SD) follow-up of 6 (5.2) months. In the review of the literature, an additional 45 patients were reported to have direct cannulation of the SOV for CCF treatment, with angiographic cure in 43 (96%) and decreased objective visual acuity in 1 (2%). CONCLUSION/CONCLUSIONS:Direct SOV cannulation to treat CCFs is safe and effective. Although it is typically used after other endovascular approaches have failed, SOV access for CCF treatment may be warranted as a first-line treatment for select patients.

BACKGROUND:Transradial artery access (TRA) for neurointerventional procedures is gaining widespread acceptance. However, complications that were previously rare may arise as TRA procedures increase. Here we report a series of retained catheter cases with a literature review. METHODS:All patients who underwent a neurointerventional procedure during a 23-month period at a single institution were retrospectively reviewed for a retained catheter in TRA cases. In cases of retained catheters, imaging was reviewed for anatomical variances in the radial artery, and clinical and demographic case details were analyzed. RESULTS:A total of 1386 nondiagnostic neurointerventional procedures were performed during the study period, 631 (46%) initially via TRA. The 631 TRA cases were performed for aneurysm embolization (n=221, 35%), mechanical thrombectomy (n=116, 18%), carotid stent/angioplasty (n=40, 6%), arteriovenous malformation embolization (n=38, 6%), and other reasons (n=216, 34%). Thirty-nine (6%) TRA procedures crossed over to femoral access, most commonly because the artery of interest could not be catheterized (26/39, 67%). A retained catheter was identified in five cases (1%), and one (0.2%) patient had an entrapped catheter that was recovered. All six patients with a retained or entrapped catheter had aberrant radial anatomy. CONCLUSION/CONCLUSIONS:Retained catheters for neurointerventional procedures performed via TRA are rare. However, this complication may be associated with variant radial anatomy. With the increased use of TRA for neurointerventional procedures, awareness of anatomical abnormalities that may lead to a retained catheter is necessary. We propose a simple protocol to avoid catheter entrapment, including in emergent situations such as TRA for stroke thrombectomy.

BACKGROUND:Optimal definitive treatment timing for patients with aneurysmal subarachnoid hemorrhage (aSAH) remains controversial. We compared outcomes for aSAH patients with ultra-early treatment versus later treatment at a single large center. METHOD:Patients who received definitive open surgical or endovascular treatment for aSAH between January 1, 2014, and July 31, 2019, were included. Ultra-early treatment was defined as occurring within 24 h from aneurysm rupture. The primary outcome was poor neurologic outcome (modified Rankin Scale score > 2). Propensity adjustment was performed for age, sex, Charlson Comorbidity Index, Hunt and Hess grade, Fisher grade, aneurysm treatment type, aneurysm type, size, and anterior location. RESULTS:Of the 1013 patients (mean [SD] age, 56 [14] years; 702 [69%] women, 311 [31%] men) included, 94 (9%) had ultra-early treatment. Compared with the non-ultra-early cohort, the ultra-early treatment cohort had a significantly lower percentage of saccular aneurysms (53 of 94 [56%] vs 746 of 919 [81%], P <0 .001), greater frequency of open surgical treatment (72 of 94 [77%] vs 523 of 919 [57%], P <0 .001), and greater percentage of men (38 of 94 [40%] vs 273 of 919 [30%], P = .04). After adjustment, ultra-early treatment was not associated with neurologic outcome in those with at least 180-day follow-up (OR = 0.86), the occurrence of delayed cerebral ischemia (OR = 0.87), or length of stay (exp(β), 0.13) (P ≥ 0.60). CONCLUSIONS:In a large, single-center cohort of aSAH patients, ultra-early treatment was not associated with better neurologic outcome, fewer cases of delayed cerebral ischemia, or shorter length of stay.

OBJECTIVE:The incidence and risk factors for chronic depression after aneurysmal subarachnoid hemorrhage (aSAH) are described. METHODS:Patients with aSAH treated at a single institution (January 1, 2003-December 31, 2019) and a modified Rankin Scale score ≤3 at follow-up who were evaluated for chronic depression were analyzed. Chronic depression was defined using a depression screening questionnaire as ≥5 positive answers for symptoms lasting >2 weeks. A predictive model was designed for the primary outcome of depression. RESULTS:Among 1419 patients with aSAH, 460 patients were analyzed; 130 (28%) had major depressive disorder. Mean follow-up was >6 years. Higher depression rates were associated with tobacco smoking (odds ratio [OR] = 2.64, P < 0.001), illicit drug use (OR = 2.35, P = 0.007), alcohol use disorder (1.92, P = 0.04), chronic obstructive pulmonary disease (COPD) (OR=2.68, P = 0.03), and vasospasm requiring angioplasty (OR=2.09, P = 0.048). The predictive model included tobacco smoking, illicit drug use, liver disease, COPD, diabetes, nonsaccular aneurysm type, anterior communicating artery or anterior cerebral artery aneurysm location, refractory spasm requiring angioplasty, and a modified Rankin Scale score at discharge of >1 (P ≤ 0.03). The model performed with appropriate goodness of fit and an area under the receiver operator curve of 0.70 for depression. Individual independent predictors of depression were tobacco smoking, COPD, diabetes, and nonsaccular aneurysm. CONCLUSIONS:A substantial percentage of patients had symptoms of depression on follow-up. The proposed predictive model for depression may be a useful clinical tool to identify patients at high risk for developing depression who warrant early screening and evaluation.

A man in his 50s presented 1 month after an automobile accident with worsening headaches and an enlarging chronic left subdural haematoma (SDH). He underwent left middle meningeal artery (MMA) embolisation. Due to tortuosity at its origin, we were unable to catheterise the MMA distally. Only proximal coil occlusion at the origin was performed. Follow-up interval head CT showed an increase in the size of the SDH with new haemorrhage, worsening mass effect and midline shift. However, he remained neurologically intact. Contralateral embolisation of the right MMA was performed with a liquid embolic agent. His headaches improved, and a follow-up head CT 3 months later showed near-complete resolution of the SDH.