CSF Susceptibility Variation in Patient With Intracranial Hemorrhage: Implications for Quantitative Susceptibility Mapping Reference Selection.

BACKGROUND: Quantitative susceptibility mapping (QSM) is an emerging MRI technique with multiple clinical applications. As tissue susceptibility cannot be directly measured using MRI, QSM imaging techniques must indirectly compute susceptibility values, requiring regularization methods. CSF is a popular choice for regularization due to its near water susceptibility in healthy controls. However, the impact of pus, elevated protein, or blood dissolved in CSF on QSM regularization is not well defined. OBJECTIVE: This study aimed to investigate the effects of intracranial hemorrhage (ICH) on selecting CSF as reference for QSM imaging. MATERIALS AND METHODS: A total of 87 subjects, 53 with ICH (5 intraventricular, 19 subarachnoid, 27 both, and 2 intraparenchymal only) and 37 without hemorrhage (27 with MS, 10 without MS), were included in this study. Imaging was performed using 3D multiecho gradient echo, FLAIR, and multiecho complex total field inversion (mcTFI) at 3 T. McTFI with and without CSF zero-referencing regularization was generated from the 3DMEGRE data and reviewed with FLAIR images. Regions of hemorrhagic (H+) and nonhemorrhagic (H-) CSF were manually selected in reference to head CT and FLAIR images by a PGY III diagnostic radiology resident and Certificate of Added Qualification-certified neuroradiologist with 10 years' experience. Paired Student t test and one-way ANOVA were used with post hoc multicomparisons. A P value <0.05 was considered statistically significant. RESULTS: Areas of H- CSF were noted to have higher regularized QSM values in subjects with ICH relative to subjects without. Unregularized H- QSM values were also noted to have a systematically higher value in ICH subjects relative to subjects without blood. Subjects with MS and without ICH did not show significant difference in H- CSF regularized or unregularized QSM values. CONCLUSIONS: QSM values of areas suggested to not have hemorrhage on other imaging showed significantly higher QSM values in ICH subjects relative to subjects without ICH. Additionally, areas of hemorrhage did not show significant QSM value difference between regularized and unregularized QSM images. These findings suggest that, in subjects with any area of ICH, QSM values for no-hemorrhagic areas may be significantly altered using CSF regularization relative to subjects without ICH, with implications for intra- and intersubject QSM value analysis.

The impact of hypertension on clinical outcomes in moyamoya disease: a multicenter, propensity score-matched analysis.

BACKGROUND: Moyamoya disease (MMD) is a rare cerebrovascular disorder characterized by progressive steno-occlusive changes in the internal carotid arteries, leading to an abnormal vascular network. Hypertension is prevalent among MMD patients, raising concerns about its impact on disease outcomes. This study aims to compare the clinical characteristics and outcomes of MMD patients with and without hypertension. METHODS: We conducted a multicenter, retrospective study involving 598 MMD patients who underwent surgical revascularization across 13 academic institutions in North America. Patients were categorized into hypertensive (n=292) and non-hypertensive (n=306) cohorts. Propensity score matching (PSM) was performed to adjust for baseline differences. RESULTS: The mean age was higher in the hypertension group (46 years vs. 36.8 years, p < 0.001). Hypertensive patients had higher rates of diabetes mellitus (45.2% vs. 10.7%, p < 0.001) and smoking (48.8% vs. 27.1%, p < 0.001). Symptomatic stroke rates were higher in the hypertension group (16% vs. 7.1%; OR: 2.48; 95% CI: 1.39-4.40, p = 0.002) before matching. After PSM, there were no significant differences in symptomatic stroke rates (11.1% vs. 7.7%; OR: 1.5; CI: 0.64-3.47, p = 0.34), perioperative strokes (6.2% vs. 2.1%; OR 3.13; 95% CI: 0.83-11.82, p = 0.09), or good functional outcomes at discharge (93% vs. 92.3%; OR 1.1; 95% CI: 0.45-2.69, p = 0.82). CONCLUSION: No significant differences in symptomatic stroke rates, perioperative strokes, or functional outcomes were observed between hypertensive and non-hypertensive Moyamoya patients. Appropriate management can lead to similar outcomes in both groups. Further prospective studies are required to validate these findings.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: Predictors of Clinical and Radiographic Failure from 636 Embolizations.

Background Knowledge regarding predictors of clinical and radiographic failures of middle meningeal artery (MMA) embolization (MMAE) treatment for chronic subdural hematoma (CSDH) is limited. Purpose To identify predictors of MMAE treatment failure for CSDH. Materials and Methods In this retrospective study, consecutive patients who underwent MMAE for CSDH from February 2018 to April 2022 at 13 U.S. centers were included. Clinical failure was defined as hematoma reaccumulation and/or neurologic deterioration requiring rescue surgery. Radiographic failure was defined as a maximal hematoma thickness reduction less than 50% at last imaging (minimum 2 weeks of head CT follow-up). Multivariable logistic regression models were constructed to identify independent failure predictors, controlling for age, sex, concurrent surgical evacuation, midline shift, hematoma thickness, and pretreatment baseline antiplatelet and anticoagulation therapy. Results Overall, 530 patients (mean age, 71.9 years ± 12.8 [SD]; 386 men; 106 with bilateral lesions) underwent 636 MMAE procedures. At presentation, the median CSDH thickness was 15 mm and 31.3% (166 of 530) and 21.7% (115 of 530) of patients were receiving antiplatelet and anticoagulation medications, respectively. Clinical failure occurred in 36 of 530 patients (6.8%, over a median follow-up of 4.1 months) and radiographic failure occurred in 26.3% (137 of 522) of procedures. At multivariable analysis, independent predictors of clinical failure were pretreatment anticoagulation therapy (odds ratio [OR], 3.23; P = .007) and an MMA diameter less than 1.5 mm (OR, 2.52; P = .027), while liquid embolic agents were associated with nonfailure (OR, 0.32; P = .011). For radiographic failure, female sex (OR, 0.36; P = .001), concurrent surgical evacuation (OR, 0.43; P = .009), and a longer imaging follow-up time were associated with nonfailure. Conversely, MMA diameter less than 1.5 mm (OR, 1.7; P = .044), midline shift (OR, 1.1; P = .02), and superselective MMA catheterization (without targeting the main MMA trunk) (OR, 2; P = .029) were associated with radiographic failure. Sensitivity analyses retained these associations. Conclusion Multiple independent predictors of failure of MMAE treatment for chronic subdural hematomas were identified, with small diameter (<1.5 mm) being the only factor independently associated with both clinical and radiographic failures. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Chaudhary and Gemmete in this issue.

Predictors of aneurysmal occlusion following intracranial aneurysms treatment with pipeline embolization device.

PURPOSE: Pipeline embolization device (PED) is thought to induce aneurysmal occlusion through diversion of flow away from the aneurysmal sac with subsequent thrombosis and endothelialization. The impact of different factors especially hypertension (HTN)-a known predisposing factor to hypercoagulability and altered endothelial function-on aneurysmal occlusion after flow diversion has not been studied. We sought to determine predictors of aneurysmal occlusion following PED treatment focusing on impact of blood pressure. METHODS: Database of patients with cerebral aneurysms treated with PED from 2013 to 2019 at our institution was retrospectively reviewed. Patients were defined as hypertensive if (1) they had a documented history of HTN requiring anti-HTN medications or (2) average systolic blood pressure on three measurements was > 130 mmHg. The primary outcome was aneurysm occlusion status at the last imaging follow-up. Multivariable logistic regression model was constructed to assess the effect of HTN on occlusion, controlling for age, smoking, aneurysmal size, fusiform morphology, posterior circulation location, and incorporated branches. RESULTS: A total of 331 aneurysms in 294 patients were identified for this analysis. The mean age was 59 years (79.9% female). Fifty-five percent of the cohort were classified as hypertensive. When controlling for other potential confounders, hypertensive patients trended toward higher odds of achieving complete occlusion compared to non-hypertensive patients (OR = 2.05; 95% CI = 0.99-4.25; p = 0.052). Meanwhile, age (OR = 0.91; 95% CI = 0.88-0.95; p < 0.001) and an incorporated branch into an aneurysm (OR = 0.22; 95% CI = 0.08-0.58; p < 0.002) were associated with decreased odds for complete aneurysmal occlusion. CONCLUSION: Hypertensive patients show a trend toward higher odds of achieving complete occlusion when controlling for potential confounders. The HTN-induced hypercoagulable state, enhanced endothelial activation, and altered extracellular matrix regulation might be the contributing factors. Further research is warranted to explore clinical implications of these findings.

Repeat Flow Diversion for Cerebral Aneurysms Failing Prior Flow Diversion: Safety and Feasibility From Multicenter Experience.

BACKGROUND: Aneurysmal persistence after flow diversion (FD) occurs in 5% to 25% of aneurysms, which may necessitate retreatment. There are limited data on safety/efficacy of repeat FD-a frequently utilized strategy in such cases. METHODS: A series of consecutive patients undergoing FD retreatment from 15 centers were reviewed (2011-2019), with inclusion criteria of repeat FD for the same aneurysm at least 6 months after initial treatment, with minimum of 6 months post-retreatment imaging. The primary outcome was aneurysmal occlusion, and secondary outcome was safety. A multivariable logistic regression model was constructed to identify predictors of incomplete occlusion (90%-99% and <90% occlusion) versus complete occlusion (100%) after retreatment. RESULTS: Ninety-five patients (median age, 57 years; 81% women) harboring 95 aneurysms underwent 198 treatment procedures. Majority of aneurysms were unruptured (87.4%), saccular (74.7%), and located in the internal carotid artery (79%; median size, 9 mm). Median elapsed time between the first and second treatment was 12.2 months. Last available follow-up was at median 12.8 months after retreatment, and median 30.6 months after the initial treatment, showing complete occlusion in 46.2% and near-complete occlusion (90%-99%) in 20.4% of aneurysms. There was no difference in ischemic complications following initial treatment and retreatment (4.2% versus 4.2%; P>0.99). On multivariable regression, fusiform morphology had higher nonocclusion odds after retreatment (odds ratio [OR], 7.2 [95% CI, 1.97-20.8]). Family history of aneurysms was associated with lower odds of nonocclusion (OR, 0.18 [95% CI, 0.04-0.78]). Likewise, positive smoking history was associated with lower odds of nonocclusion (OR, 0.29 [95% CI, 0.1-0.86]). History of hypertension trended toward incomplete occlusion (OR, 3.10 [95% CI, 0.98-6.3]), similar to incorporated branch into aneurysms (OR, 2.78 [95% CI, 0.98-6.8]). CONCLUSIONS: Repeat FD for persistent aneurysms carries a reasonable success/safety profile. Satisfactory occlusion (100% and 90%-99% occlusion) was encountered in two-thirds of patients, with similar complications between the initial and subsequent retreatments. Fusiform morphology was the strongest predictor of retreatment failure.

Sodium Variability and Probability of Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage.

OBJECTIVES: Vasospasm is a well-known complication of aneurysmal subarachnoid hemorrhage (aSAH) that generally occurs 4-14 days post-hemorrhage. Based on American Heart Association guidelines, the current understanding is that hyponatremic episodes may lead to vasospasm. Therefore, we sought to determine the association between repeated serum sodium levels of aSAH patients and its relationship to radiographic vasospasm. MATERIALS AND METHODS: A single-center retrospective analysis from 2007-2016 was conducted of aSAH patients. Daily serum sodium levels were recorded up to day 14 post-admission. Hyponatremia was defined as a serum sodium value of < 135 mEq/L. We evaluated the relationship to radiologic vasospasm, neurologic deterioration, functional status at discharge, and mortality. A repeated measures analysis using a mixed-effect regression model was performed to assess the interindividual relationship between serum sodium trends and outcomes. RESULTS: A total of 271 aSAH patients were included. There were no significant differences in interindividual serum sodium values over time and occurrence of radiographic vasospasm, neurologic deterioration, functional, or mortality outcomes (p = .59, p = .42, p = .94, p = .99, respectively) using the mixed-effect regression model. However, overall mean serum sodium levels were significantly higher in patients who had neurologic deterioration, poor functional outcome (mRS 3-6), and mortality. CONCLUSIONS: Serum sodium level variations are not associated with subsequent development of cerebral vasospasm in aSAH patients. These findings indicate that serum sodium may not have an impact on vasospasm, and avoiding hypernatremia may provide a neurologic, functional and survival benefit.

Quantitative Susceptibility Mapping for Staging Acute Cerebral Hemorrhages: Comparing the Conventional and Multiecho Complex Total Field Inversion magnetic resonance imaging MR Methods.

BACKGROUND: The perceived acuity of intracerebral hemorrhage (ICH) impacts the management of patients, both within emergent and outpatient/urgent settings. Morphology enabled dipole inversion (MEDI) quantitative susceptibility imaging (QSM) has improved characterization of ICH acuity, despite outstanding limitations in distinguishing blood products. PURPOSE/HYPOTHESIS: Using improved susceptibility quantification, novel postprocessing QSM method from multiecho complex total field inversion (mcTFI) may better discriminate between acute and subacute ICH, compared to MEDI. STUDY TYPE: Retrospective cohort study. SUBJECTS: A total of 121 subjects enrolled following positive computerized tomography (CT) findings for ICH. Subjects were grouped based on time between admission and MR imaging: hyperacute (<24 hours), acute (1-3 days), early subacute (3-7 days), and late subacute (7-18 days). FIELD STRENGTH/SEQUENCE: A multiecho gradient echo sequence at 3.0 T was paired with clinical noncontrast CT imaging. ASSESSMENT: A quantitative index (CTindex ) was derived based on relative intensities of blood on noncontrast CT. All images were co-registered, from which QSM parameters within the ICH area were assessed across groups, as well as the correlation with CTindex . STATISTICAL TESTS: Group differences were assessed using ANOVAs. Linear regressions between the CTindex , MEDI, and mcTFI measurements were used to assess their relationships. Statistical significance was set at P < 0.05. RESULTS: A total of 21 hyperacute, 72 acute, 21 early subacute, and 7 late-subacute patients were included in this analysis. Significant changes in blood susceptibility were found over time for the MEDI and mcTFI, although mcTFI better differentiated the hyperacute/acute from subacute stages. CTindex values within the ICH were more strongly correlated with mcTFI QSM (r = 0.727) than MEDI (r = 0.412) QSM. DATA CONCLUSION: McTFI susceptibility estimation demonstrated better correlation with ICH acuity as suggested by CT, providing an improved method to assess acuity of intracranial blood products in clinical settings to identify cases that may require acute intervention. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.

Flow diversion for treatment of intracranial aneurysms: Mechanism and implications.

Flow diverters are new generation stents that have recently garnered a large amount of interest for use in treatment of intracranial aneurysms. Flow diverters reduce blood flow into the aneurysm, with redirection along the path of the parent vessel. Flow stagnation into the aneurysm and neck coverage with subsequent endothelialization are the important synergistic mechanisms by which the therapy acts. Several studies have examined the mechanisms by which flow diverters subsequently lead to aneurysm occlusion. This review aims to provide a general overview of the flow diverters and their mechanism of action and potential implications. ANN NEUROL 2019;85:793-800.

Cigarette smoking and risk of intracranial aneurysms in middle-aged women.

BACKGROUND AND PURPOSE: We previously reported a single-centre study demonstrating that smoking confers a six-fold increased risk for having an unruptured intracranial aneurysm (UIA) in women aged between 30 and 60 years and this risk was higher if the patient had chronic hypertension. There are no data with greater generalisability evaluating this association. We aimed to validate our previous findings in women from a multicentre study. METHODS: A multicentre case-control study on women aged between 30 and 60 years, that had magnetic resonance angiography (MRA) during the period 2016-2018. Cases were those with an incidental UIA, and these were matched to controls based on age and ethnicity. A multivariable conditional logistic regression was conducted to evaluate smoking status and hypertension differences between cases and controls. RESULTS: From 545 eligible patients, 113 aneurysm patients were matched to 113 controls. The most common reason for imaging was due to chronic headaches in 62.5% of cases and 44.3% of controls. A positive smoking history was encountered in 57.5% of cases and in 37.2% of controls. A multivariable analysis demonstrated a significant association between positive smoking history (OR 3.7, 95%CI 1.61 to 8.50), hypertension (OR 3.16, 95% CI 1.17 to 8.52) and both factors combined with a diagnosis of an incidental UIA (OR 6.9, 95% CI 2.49 to 19.24). CONCLUSIONS: Women aged between 30 and 60 years with a positive smoking history have a four-fold increased risk for having an UIA, and a seven-fold increased risk if they have underlying chronic hypertension. These findings indicate that women aged between 30 and 60 years with a positive smoking history might benefit from a screening recommendation.

Middle meningeal artery embolization treatment of nonacute subdural hematomas in the elderly: a multiinstitutional experience of 151 cases.

OBJECTIVE: The incidence of already common chronic subdural hematomas (CSDHs) and other nonacute subdural hematomas (NASHs) in the elderly is expected to rise as the population ages over the coming decades. Surgical management is associated with recurrence and exposes elderly patients to perioperative and operative risks. Middle meningeal artery (MMA) embolization offers the potential for a minimally invasive, less morbid treatment in this age group. The clinical and radiographic outcomes after MMA embolization treatment for NASHs have not been adequately described in elderly patients. In this paper, the authors describe the clinical and radiographic outcomes after 151 cases of MMA embolization for NASHs among 121 elderly patients. METHODS: In a retrospective review of a prospectively maintained database across 15 US academic centers, the authors identified patients aged ≥ 65 years who underwent MMA embolization for the treatment of NASHs between November 2017 and February 2020. Patient demographics, comorbidities, clinical and radiographic factors, treatment factors, and clinical outcomes were abstracted. Subgroup analysis was performed comparing elderly (age 65-79 years) and advanced elderly (age > 80 years) patients. RESULTS: MMA embolization was successfully performed in 98% of NASHs (in 148 of 151 cases) in 121 patients. Seventy elderly patients underwent 87 embolization procedures, and 51 advanced elderly patients underwent 64 embolization procedures. Elderly and advanced elderly patients had similar rates of embolization for upfront (46% vs 61%), recurrent (39% vs 33%), and prophylactic (i.e., with concomitant surgical intervention; 15% vs 6%) NASH treatment. Transfemoral access was used in most patients, and the procedure time was approximately 1 hour in both groups. Particle embolization with supplemental coils was most common, used in 51% (44/87) and 44% (28/64) of attempts for the elderly and advanced elderly groups, respectively. NASH thickness decreased significantly from initial thickness to 6 weeks, with additional decrease in thickness observed in both groups at 90 days. At longest follow-up, the treated NASHs had stabilized or improved in 91% and 98% of the elderly and advanced elderly groups, respectively, with > 50% improvement seen in > 60% of patients for each group. Surgical rescue was necessary in 4.6% and 7.8% of cases, and the overall mortality was 8.6% and 3.9% for elderly and advanced elderly patients, respectively. CONCLUSIONS: MMA embolization can be used safely and effectively as an alternative or adjunctive minimally invasive treatment for NASHs in elderly and advanced elderly patients.

Moyamoya disease in pregnancy: a systematic review.

BACKGROUND: Moyamoya disease (MMD) management during pregnancy poses a challenge to health care providers, and recommendations are outdated, vague, and controversial. We conducted a systematic review to investigate and present the available evidence. METHOD: We searched five online databases and bibliographies of relevant published original studies to identify case reports, case series, cohort studies, and reviews reporting on patients diagnosed with MMD before, during, or shortly after pregnancy. We report and analyze the respective data. RESULTS: Fifty-four relevant articles were identified. In the group of patients with MMD diagnosed prior to pregnancy, 68.7% had previously undergone bypass surgery, 64.5% delivered via cesarean section, 95.2% of mothers had good outcomes, and no bad fetal outcomes were reported. In patients first diagnosed with MMD due to a cerebrovascular accident during pregnancy, the mean gestational age on symptom onset was 28.7 weeks and 69.5% presented with cerebral hemorrhage. In this group, 57.2% received neurosurgical operative management, and 80% underwent cesarean section with 13.6% maternal mortality and 23.5% fetal demise. In patients diagnosed with MMD immediately postpartum, 46.6% suffered a cerebrovascular event within 3 days of delivery, 78.3% of which were ischemic. Only 15.3% underwent surgical hematoma evacuation and one patient (9%) expired. CONCLUSIONS: MMD may coincide with pregnancy, but there is paucity of high-quality data. It appears that MMD is not a contraindication to pregnancy, if blood pressure and ventilation are properly managed. There is no clear evidence that bypass surgery before pregnancy or cesarean mode of delivery improve outcomes.

Accuracy and Safety of External Ventricular Drain Placement by Physician Assistants and Nurse Practitioners in Aneurysmal Acute Subarachnoid Hemorrhage.

BACKGROUND: In the current dynamic health environment, increasing number of procedures are being completed by advanced practitioners (nurse practitioners and physician assistants). This is the first study to assess the clinical outcomes and safety of external ventricular drain (EVD) placements by specially trained advanced practitioners. OBJECTIVE: Compare the safety and outcomes of EVD placement by advanced practitioners in patients with subarachnoid hemorrhage (SAH). METHODS: A cohort comparison study was performed from an aneurysmal SAH database selecting patients treated with EVD from a single major academic institution in the USA between June 2007 and June 2017. Safety, accuracy, and complications of EVD placement were compared between advanced practitioners and neurosurgical physicians (attending neurosurgeon and subspecialty clinical fellow). Statistical analysis was performed using the Mann-Whitney test for continuous variables and χ2 test for categorical variables, with p values set at < 0.05 for significance. RESULTS: We identified 203 patients for this cohort with 238 EVD placements; eighty-seven (36.6%) placements were performed by advanced practitioners and 151 (63.4%) by neurosurgeons. Most of the ventriculostomies were placed in the emergency room (n = 114; 47.9%). Additional procedures performed concurrently with the EVD placements were significantly higher among the physicians' group (21.8 vs. 4.6%; p < 0.001). Bedside placement and usage of Ghajar guide were significantly higher among advanced practitioner's (58.3 vs. 98.9 and 9.9 vs. 64.4%, respectively, with a p < 0.001 for both). There were, however, no significant differences in terms of the number of attempts for insertion, intraprocedural complications, tract hemorrhages, accuracy, infection rates, catheter dislodgments, and need for repositioning/replacement of EVD. CONCLUSION: After appropriate training, EVD placement can be safely performed by advanced practitioners with an adequate accuracy of placement.

Angiographic Findings in the Tolosa-Hunt Syndrome and Resolution after Corticosteroid Treatment.

The Tolosa-Hunt syndrome is a rare clinical condition characterized by painful opthalmoparesis associated with idiopathic granulomatous inflammation of the orbital apex and cavernous sinus. Historically, this condition was thought to result from arteritic changes in the internal carotid artery and cavernous sinus. Modern digital angiographic techniques were unavailable when THS was initially described, and few reports exist on its high-resolution angiographic findings. Painful ophthalmoparesis, especially of the oculomotor nerve, warrants vascular imaging because of the concern for an underlying aneurysm. Here, we describe angiographic findings of THS which may be useful for clinicians when encountering patients presenting with painful ophthalmoplegia.

Aspirin and Risk of Subarachnoid Hemorrhage: Systematic Review and Meta-Analysis.

BACKGROUND AND PURPOSE: Recent studies have suggested that the use of low-dose aspirin may reduce the risk of aneurysmal subarachnoid hemorrhage (aSAH). We aimed to evaluate any association between aspirin use and risk of aSAH based on the literature, and whether this is influenced by duration or frequency of aspirin use. METHODS: A search of electronic databases was done from inception to September 2016. For each study, data on risk of aSAH in aspirin versus nonaspirin users were used to generate odds ratios and 95% confidence intervals, and combined using inverse variance-weighted averages of logarithmic odds ratios in a random-effects models. RESULTS: From 7 included studies, no significant difference was noted between aspirin use of any duration or frequency and nonaspirin users (odds ratio, 1.00; 95% confidence interval, 0.81-1.24; P=0.99). We found a significant association between short-term use of aspirin (<3 months) and the risk of aSAH (odds ratio, 1.61; 95% confidence interval, 1.20-2.18; P=0.002). No significant difference was found in terms of risk of aSAH for 3 to 12 months, 1 to 3 years, and >3 years of durations of use. No significant association was found between infrequent aspirin use (≤2× per week) or frequent use (≥3× per week) with risk of aSAH. CONCLUSIONS: Current evidence suggests that short-term (<3 months) use of aspirin is associated with increased risk of aSAH. Limitations include substantial heterogenity of the included studies. The role of long-term aspirin in reducing risk of aSAH remains unclear and ideally should be addressed by an appropriately designed randomized controlled trial.

Use of Platelet Function Testing Before Pipeline Embolization Device Placement: A Multicenter Cohort Study.

BACKGROUND AND PURPOSE: Thromboembolic complications constitute a significant source of morbidity after neurointerventional procedures. Flow diversion using the pipeline embolization device for the treatment of intracranial aneurysms necessitates the use of dual antiplatelet therapy to reduce this risk. The use of platelet function testing before pipeline embolization device placement remains controversial. METHODS: A retrospective review of prospectively maintained databases at 3 academic institutions was performed from the years 2009 to 2016 to identify patients with intracranial aneurysms treated with pipeline embolization device placement. Clinical and radiographic data were analyzed with emphasis on thromboembolic complications and clopidogrel responsiveness. RESULTS: A total of 402 patients underwent 414 pipeline embolization device procedures for the treatment of 465 intracranial aneurysms. Thromboembolic complications were encountered in 9.2% of procedures and were symptomatic in 5.6%. Clopidogrel nonresponders experienced a significantly higher rate of thromboembolic complications compared with clopidogrel responders (17.4% versus 5.6%). This risk was significantly lower in nonresponders who were switched to ticagrelor when compared with patients who remained on clopidogrel (2.7% versus 24.4%). In patients who remained on clopidogrel, the rate of thromboembolic complications was significantly lower in those who received a clopidogrel boost within 24 hours pre-procedure when compared with those who did not (9.8% versus 51.9%). There was no significant difference in the rate of hemorrhagic complications between groups. CONCLUSIONS: Clopidogrel nonresponders experienced a significantly higher rate of thromboembolic complications when compared with clopidogrel responders. However, this risk seems to be mitigated in nonresponders who were switched to ticagrelor or received a clopidogrel boost within 24 hours pre-procedure.

Ischemic Stroke After Treatment of Intraprocedural Thrombosis During Stent-Assisted Coiling and Flow Diversion.

BACKGROUND AND PURPOSE: Intraprocedural thrombosis poses a formidable challenge during neuroendovascular procedures because the risks of aggressive thromboembolic treatment must be balanced against the risk of postprocedural hemorrhage. The aim of this study was to identify predictors of ischemic stroke after intraprocedural thrombosis after stent-assisted coiling and pipeline embolization device placement. METHODS: A retrospective analysis of intracranial aneurysms treated with stent-assisted coiling or pipeline embolization device placement between 2007 and 2016 at 4 major academic institutions was performed to identify procedures that were complicated by intraprocedural thrombosis. RESULTS: Intraprocedural thrombosis occurred in 34 (4.6%) procedures. Postprocedural ischemic stroke and hemorrhage occurred in 20.6% (7/34) and 11.8% (4/34) of procedures complicated by intraprocedural thrombosis, respectively. Current smoking was an independent predictor of ischemic stroke. There was no statistically significant difference in the rate of ischemic stroke or postprocedural hemorrhage with the use of abciximab compared with the use of eptifibatide in treatment of intraprocedural thrombosis. CONCLUSIONS: Current protocols for treatment of intraprocedural thrombosis associated with placement of intra-arterial devices were effective in preventing ischemic stroke in ≈80% of cases. Current smoking was the only independent predictor of ischemic stroke.

Documentation of Improved Outcomes for Intracranial Aneurysm Management Over a 15-Year Interval.

BACKGROUND AND PURPOSE: Despite rapid advancements in intracranial aneurysm management, there is no evidence as of yet that this has translated into improvement in overall prognosis. METHODS: We compared 2 periods of aneurysm management, 1998 to 2003 (n=1023 aneurysms) and 2007 to 2013 (n=1499 aneurysms), at a single, high-volume neurovascular center. Our outcome of interest was low or moderate disability (Glasgow Outcome Scale score of 4 or 5) at 6 months or more post treatment. RESULTS: There were significant improvements in outcome for surgical, endovascular, and overall treatment of unruptured (adjusted odds ratio [OR], 2.33; P=0.0091; adjusted OR, 4.40; P=0.0271; and adjusted OR, 2.58; P=0.0008, respectively) and ruptured (adjusted OR, 3.18; P=0.0004; adjusted OR, 3.54; P=0.0001; and adjusted OR, 3.11; P<0.0001, respectively) aneurysms from the first to the second time period. In 2007 to 2013, the proportion of cases with low or moderate disability at 6 months post subarachnoid hemorrhage was 75.6% for surgical clipping and 76.6% for endovascular therapy. CONCLUSIONS: We report significantly improved outcomes over time for overall aneurysm management and for multiple patient subgroups, associated with increased usage of endovascular therapy.

Dementia resulting from expansion of basilar artery aneurysm: two case reports and a review of the literature.

BACKGROUND: Dementia places a large burden on the economy, with financial and emotional costs incurred by patients, caregivers and the health sector. METHODS AND RESULTS: We report the first published case series of giant basilar aneurysm leading to progressive cognitive and functional decline. We review the literature regarding giant aneurysms and their association with dementia and the possible underlying pathophysiological mechanism. CONCLUSIONS: This report highlights a number of therapeutic considerations when determining the best management strategy for these difficult lesions.

Clinical presentation, progression, and treatment outcomes of moyamoya disease in the elderly.

BACKGROUND: Moyamoya disease is a vascular disorder characterized by progressive stenosis of the internal carotid artery. The presentation, progression, treatment options, and post-operative clinical outcomes for elderly (60 and older) Moyamoya patients have never been reported. METHODS: A retrospective analysis of all patients who were diagnosed with Moyamoya disease by the senior authors between 1991 and 2016 was performed. Patients who were 60 years or older at the time of surgery or last follow-up were further evaluated. RESULTS: Seventy patients were diagnosed with probable or definite Moyamoya disease during the study period (1991-2016). Eight patients (11.4 %; six females: two males; median age 63; range, 60-71 years) were found to be 60 years or older at the time of surgery or last follow-up and were included in the study. All patients had a modified Rankin scale (mRS) of either one or two (median 1) pre-operatively. Six patients (75 %) underwent surgical treatment on a total on seven hemispheres. Post-surgery, one patient had an improved mRS score, three had no changes, and two had worsening in their mRS scores. Both patients who did not undergo surgical interventions suffered from intra-parenchymal hemorrhages post-diagnosis. CONCLUSIONS: Moyamoya disease is most commonly seen in young and middle-aged patients. Presentation in the elderly (defined as 60 years and older in this study) is rare, and has never been reported in the literature. In this study, both direct and indirect revascularization procedures demonstrated potential benefit in some of these patients, with stabilization of progressive symptoms.

Removal of symptomatic titanium fixation plates after craniotomy.

INTRODUCTION: Titanium fixation plates are routinely used for rigid fixation of bone flaps after craniotomy. In craniofacial surgery or after craniotomy involving orbitozygomatic osteotomies, these plates are occasionally removed because of infection, pain, protrusion, soft tissue erosion, and plate malfunction. However, plate removal because of pain and protrusion after craniotomy without orbitozygomatic osteotomy has rarely been reported. METHODS: A retrospective analysis of all patients who underwent removal of cranial fixation plates after craniotomy, performed by the senior authors at one institution between 2014 and 2016, was conducted. RESULTS: A total of 319 patients underwent bone flap fixation after craniotomy using cranial fixation plates between 2014 and 2016. Five of those patients (1.6 %) had their cranial plates removed because of pain and protrusion. An additional four patients had a cranial fixation plate removed during that time frame with the original craniotomy performed before 2014. All nine patients had immediate resolution of symptoms after plate removal. CONCLUSION: We report our experience with cranial fixation plate removal because of pain and protrusion in patients who underwent craniotomy without orbitozygomatic osteotomy, particularly frontotemporal craniotomy. In an attempt to reduce this complication, we recently stopped placing a full-size burr hole in the keyhole area of a frontotemporal craniotomy, eliminating the need for a titanium burr hole cover plate.