Assessment of multimodal treatment options in recurrent and persistent acromegaly: a systematic review and meta-analysis.

PURPOSE: In patients with acromegaly, secondary treatment options in cases of hormonal non-remission or tumor progression include repeat transsphenoidal surgery (TSS), radiation-based treatment (RT), or medical therapy (MT). In this study, we aim to evaluate the clinical effectiveness of various second-line treatment options for acromegaly. METHODS: Using the PRISMA guideline, a systematic review was performed by searching MEDLINE (PubMed), Web of Science, Scopus, and Cochrane electronic bibliographic databases from conception to the end of 2022. Outcomes of interest included hormonal remission rate, complications, and mortality associated with each treatment modality for refractory acromegaly. RESULTS: A total of 79 studies including 3,208 refractory acromegaly patients (44.90% males) were analyzed, with a mean patient age of 43.89 years. There was a statistically significant difference between various therapeutic modalities in terms of remission rate, with MT offering the highest remission rate (62.55%), followed by RT (50.15%) and TSS (37.39%). Subgroup analysis of radiotherapeutic and medical modalities did not show a significant difference in remission rate between different kinds of sub-modalities in each treatment approach. Recurrence following secondary treatment was not different in patients treated with reoperation TSS compared to other modalities. CONCLUSIONS: The management of persistent and recurrent acromegaly optimally requires a multimodal approach. In different scenarios of refractory acromegaly based on previous treatment, secondary treatments may vary in terms of remission rate and complications. Medical agents provide considerable effectiveness as a second-line therapy for recurrent or persistent disease. In selected cases, however, reoperation still provides an opportunity for cure or freedom from medications. The findings of this study may help clinicians to prioritize varying options involved in this multifaceted decision-making process.

The Influence of Coagulopathy on Radiographic and Clinical Outcomes in Patients Undergoing Middle Meningeal Artery Embolization as Standalone Treatment for Non-acute Subdural Hematomas.

Middle meningeal artery embolization (MMAE) is emerging as a safe and effective standalone intervention for non-acute subdural hematomas (NASHs); however, the risk of hematoma recurrence after MMAE in coagulopathic patients is unclear. To characterize the impact of coagulopathy on treatment outcomes, we analyzed a multi-institutional database of patients who underwent standalone MMAE as treatment for NASH. We classified 537 patients who underwent MMAE as a standalone intervention between 2019 and 2023 by coagulopathy status. Coagulopathy was defined as use of anticoagulation/antiplatelet agents or pre-operative thrombocytopenia (platelets <100,000/µL). Demographics, pre-procedural characteristics, in-hospital course, and patient outcomes were collected. Thrombocytopenia, aspirin use, antiplatelet agent use, and anticoagulant use were assessed using univariate and multivariate analyses to identify any characteristics associated with the need for rescue surgical intervention, mortality, adverse events, and modified Rankin Scale score at 90-day follow-up. Propensity score-matched cohorts by coagulopathy status with matching covariates adjusting for risk factors implicated in surgical recurrence were evaluated by univariate and multivariate analyses. Minimal differences in pre-operative characteristics between patients with and those without coagulopathy were observed. On unmatched and matched analyses, patients with coagulopathy had higher rates of requiring subsequent surgery than those without (unmatched: 9.9% vs. 4.3%; matched: 12.6% vs. 4.6%; both p < 0.05). On matched multivariable analysis, patients with coagulopathy had an increased odds ratio (OR) of requiring surgical rescue (OR 3.95; 95% confidence interval [CI] 1.68-9.30; p < 0.01). Antiplatelet agent use (ticagrelor, prasugrel, or clopidogrel) was also predictive of surgical rescue (OR 4.38; 95% CI 1.51-12.72; p = 0.01), and patients with thrombocytopenia had significantly increased odds of in-hospital mortality (OR 5.16; 95% CI 2.38-11.20; p < 0.01). There were no differences in follow-up radiographic and other clinical outcomes in patients with and those without coagulopathy. Patients with coagulopathy undergoing standalone MMAE for treatment of NASH may have greater risk of requiring surgical rescue (particularly in patients using antiplatelet agents), and in-hospital mortality (in thrombocytopenic patients).

General Versus Nongeneral Anesthesia for Middle Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score Matched Study.

BACKGROUND AND OBJECTIVES: The choice of anesthesia type (general anesthesia [GA] vs nongeneral anesthesia [non-GA]) in middle meningeal artery embolization (MMAE) procedures for chronic subdural hematomas (cSDH) differs between institutions and left to care team discretion given lack of standard guidelines. We compare the outcomes of GA vs non-GA in MMAE. METHODS: Consecutive patients receiving MMAE for cSDH at 14 North American centers (2018-2023) were included. Clinical, cSDH characteristics, and technical/clinical outcomes were compared between the GA/non-GA groups. Using propensity score matching (PSM), patients were matched controlling for age, baseline modified Rankin Scale, concurrent/prior surgery, hematoma thickness/midline shift, and baseline antiplatelet/anticoagulation. The primary end points included surgical rescue and radiographic success rates (≥50% reduction in maximum hematoma thickness with minimum 2 weeks of imaging). Secondary end points included technical feasibility, procedural complications, and functional outcomes. RESULTS: Seven hundred seventy-eight patients (median age 73 years, 73.2% male patients) underwent 956 MMAE procedures, 667 (70.4%) were non-GA and 280 were GA (29.6%). After running 1:3 PSM algorithm, this resulted in 153 and 296 in the GA and non-GA groups, respectively. There were no baseline/procedural differences between the groups except radial access more significantly used in the non-GA group (P = .001). There was no difference between the groups in procedural technical feasibility, complications rate, length of stay, surgical rescue rates, or favorable functional outcome at the last follow-up. Subsequent 1:1 sensitivity PSM retained the same results. Bilateral MMAE procedures were more performed under non-GA group (75.8% vs 67.2%; P = .01); no differences were noted in clinical/radiographic outcomes between bilateral vs unilateral MMAE, except for longer procedure duration in the bilateral group (median 73 minutes [IQR 48.3-100] vs 54 minutes [39-75]; P < .0001). Another PSM analysis comparing GA vs non-GA in patients undergoing stand-alone MMAE retained similar associations. CONCLUSION: We found no significant differences in radiological improvement/clinical outcomes between GA and non-GA for MMAE.

Direct Versus Indirect Revascularization for Moyamoya: a Large Multicenter Study.

BACKGROUND: Moyamoya is a chronic occlusive cerebrovascular disease of unknown etiology causing neovascularization of the lenticulostriate collaterals at the base of the brain. Although revascularization surgery is the most effective treatment for moyamoya, there is still no consensus on the best surgical treatment modality as different studies provide different outcomes. OBJECTIVE: In this large case series, we compare the outcomes of direct (DR) and indirect revascularisation (IR) and compare our results to the literature in order to reflect on the best revascularization modality for moyamoya. METHODS: We conducted a multicenter retrospective study in accordance with the Strengthening the Reporting of Observational studies in Epidemiology guidelines of moyamoya affected hemispheres treated with DR and IR surgeries across 13 academic institutions predominantly in North America. All patients who underwent surgical revascularization of their moyamoya-affected hemispheres were included in the study. The primary outcome of the study was the rate of symptomatic strokes. RESULTS: The rates of symptomatic strokes across 515 disease-affected hemispheres were comparable between the two cohorts (11.6% in the DR cohort vs 9.6% in the IR cohort, OR 1.238 (95% CI 0.651 to 2.354), p=0.514). The rate of total perioperative strokes was slightly higher in the DR cohort (6.1% for DR vs 2.0% for IR, OR 3.129 (95% CI 0.991 to 9.875), p=0.052). The rate of total follow-up strokes was slightly higher in the IR cohort (8.1% vs 6.6%, OR 0.799 (95% CI 0.374 to 1.709) p=0.563). CONCLUSION: Since both modalities showed comparable rates of overall total strokes, both modalities of revascularization can be performed depending on the patient's risk assessment.

Ferroptosis as a Therapeutic Target in Subarachnoid Hemorrhage.

Subarachnoid hemorrhage (SAH) is a cerebrovascular disorder with significant mortality and morbidity. Neural injury in SAH is mediated through a variety of pathophysiological processes. Currently available treatments are either nonspecific in targeting the basic pathophysiological mechanisms that result in neural damage in SAH, or merely focus on vasospasm. Ferroptosis is a type of programmed iron dependent cell death, which has received attention due to its possible role in neural injury in SAH. Herein, we review how intracellular iron overload mediates the production of reactive free radicals and lipid peroxidation through a variety of biochemical pathways in SAH. This in turn results in induction of ferroptosis, as well as exacerbation of vasospasm. We also discuss several therapeutic agents that have been shown to inhibit ferroptosis through targeting different steps of the process. Such agents have proven effective in ameliorating vasospasm, neural damage, and neurobehavioral outcomes in animal models of SAH. Human studies to test the safety and efficacy of intrathecal or parenteral administration of the inhibitors of ferroptosis in improving outcomes of SAH patients are warranted. There are currently a few ongoing clinical trials pursuing this therapeutic concept, the results of which will be critical to determine the value of ferroptosis as a novel therapeutic target in SAH.

The effect of patient age on the degree of midline shift caused by chronic subdural hematomas: a volumetric analysis.

OBJECTIVE: Chronic subdural hematomas (CSDHs) are the among the most common conditions treated by neurosurgeons. Midline shift (MLS) is used as a radiological marker of CSDH severity and the potential need for urgent surgical evacuation. However, a patient's age may affect the degree of MLS for a given hematoma volume. This study aimed to investigate the correlation between the patient's age and the MLS caused by CSDH. METHODS: The database of patients treated for CSDH was reviewed in a single institution. Patients with unilateral CSDH were included. To measure CSDH volume, the preprocedural head CT scans underwent 3D volumetric reconstruction using the TeraRecon software. The effect of age on MLS after adjusting for CSDH volume was investigated using linear regression analysis. RESULTS: Sixty-nine hematomas in 69 patients were included. The age of patients ranged from 25 to 94 years (mean 71.6 years). Hematoma volume and MLS ranged from 27.8 to 215 mL (mean 99.3 mL) and 0-17 mm (mean 6.5 mm), respectively. On multivariate regression analysis, MLS showed a significant independent negative correlation with age after adjusting for CSDH volume (OR -0.11, 95% CI -0.16 to -0.06; p < 0.001), meaning that for a fixed CSDH volume, with each 10-year increase in age the MLS will reduce by 1.1 mm. Moreover, MLS-to-volume ratio showed a significant negative linear correlation with age (r2 = 0.32; p < 0.001). Ten-milliliter increments in CSDH volume resulted in a 1.09-mm increase in MLS in patients younger than 60 years, which is 2.4-fold higher compared to the 0.46-mm increase in those older than 75 years (p < 0.001). CONCLUSIONS: For a fixed CSDH volume, older age correlates with significantly lower MLS. This could be explained by higher parenchymal compliance in older individuals due to increased brain atrophy, and a larger subdural space. Clinical use of MLS to estimate severity of CSDH and gauge treatment decisions should take the patient's age into account.

Radiosurgery With Prior Embolization Versus Radiosurgery Alone for Intracranial Arteriovenous Malformations: A Systematic Review and Meta-Analysis.

BACKGROUND AND OBJECTIVES: The addition of adjuvant embolization to radiosurgery has been proposed as a means of improving treatment outcomes of intracranial arteriovenous malformations (AVMs). However, the relative efficacy and safety of radiosurgery with adjuvant embolization vs radiosurgery alone remain uncertain. Moreover, previous systematic reviews and meta-analyses have included a limited number of studies and did not consider the effects of baseline characteristics, including AVM volume, on the outcomes. This systematic review aimed to evaluate the efficacy of preradiosurgery embolization for intracranial AVMs with consideration to matching status between participants in each treatment group. METHODS: A systematic review and meta-analysis were conducted by searching electronic databases, including PubMed, Scopus, and Cochrane Library, up to January 2023. All studies evaluating the utilization of preradiosurgery embolization were included. RESULTS: A total of 70 studies (9 matched and 71 unmatched) with a total of 12 088 patients were included. The mean age of the included patients was 32.41 years, and 48.91% of the patients were female. Preradiosurgery embolization was used for larger AVMs and patients with previous hemorrhage ( P < .01, P = .02, respectively). The obliteration rate for preradiosurgery embolization (49.44%) was lower compared with radiosurgery alone (61.42%, odds ratio = 0.56, P < .01), regardless of the matching status of the analyzed studies. Although prior embolization was associated higher rate of cyst formation ( P = .04), it lowered the odds of radiation-induced changes ( P = .04). The risks of minor and major neurological deficits, postradiosurgery hemorrhage, and mortality were comparable between groups. CONCLUSION: This study provides evidence that although preradiosurgery embolization is a suitable option to reduce the AVM size for future radiosurgical interventions, it may not be useful for same-sized AVMs eligible for radiosurgery. Utilization of preradiosurgery embolization in suitable lesions for radiosurgery may result in the added cost and burden of an endovascular procedure.

Standalone middle meningeal artery embolization versus middle meningeal artery embolization with concurrent surgical evacuation for chronic subdural hematomas: a multicenter propensity score matched analysis of clinical and radiographic outcomes.

BACKGROUND: Middle meningeal artery embolization (MMAE) has emerged as a promising therapy for chronic subdural hematomas (cSDHs). The efficacy of standalone MMAE compared with MMAE with concurrent surgery is largely unknown. METHODS: cSDH patients who underwent successful MMAE from 14 high volume centers with at least 30 days of follow-up were included. Clinical and radiographic variables were recorded and used to perform propensity score matching (PSM) of patients treated with standalone MMAE or MMAE with concurrent surgery. Multivariable logistic regression models were used for additional covariate adjustments. The primary outcome was recurrence requiring surgical rescue, and the secondary outcome was radiographic failure defined as <50% reduction of cSDH thickness. RESULTS: 722 MMAE procedures in 588 cSDH patients were identified. After PSM, 230 MMAE procedures remained (115 in each group). Median age was 73 years, 22.6% of patients were receiving anticoagulation medication, and 47.9% had no preoperative functional disability. Median midline shift was 4 mm and cSDH thickness was 16 mm, representing modestly sized cSDHs. Standalone MMAE and MMAE with surgery resulted in similar rates of surgical rescue (7.8% vs 13.0%, respectively, P=0.28; adjusted OR (aOR 0.73 (95% CI 0.20 to 2.40), P=0.60) and radiographic failure (15.5% vs 13.7%, respectively, P=0.84; aOR 1.08 (95% CI 0.37 to 2.19), P=0.88) with a median follow-up duration of 105 days. These results were similar across subgroup analyses and follow-up durations. CONCLUSIONS: Standalone MMAE led to similar and durable clinical and radiographic outcomes as MMAE combined with surgery in select patients with moderately sized cSDHs and mild clinical disease.

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.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020.

BACKGROUND: The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time. METHODS: A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests. RESULTS: A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987. CONCLUSIONS: The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Cigarette Smoking as a Risk Factor for Hematoma Expansion in Primary Intracerebral Hemorrhage: Analysis From a Randomized Clinical Trial.

Background Cigarette smoking is a well-known risk factor for ischemic and hemorrhagic stroke. We evaluated the impact of smoking status on hematoma expansion and clinical outcome in patients with primary intracerebral hemorrhage. Methods and Results This is a post hoc exploratory analysis of the ATACH (Antihypertensive Treatment at Acute Cerebral Hemorrhage)-2 trial. Patients with intracerebral hemorrhage were randomized into intensive blood pressure lowering (systolic blood pressure, <139 mm Hg) versus standard blood pressure lowering (systolic blood pressure, 140-179 mm Hg) in this study. We compared the demographic characteristics; hematoma size, location, and expansion rate; and clinical outcome based on subjects' smoking status. Of a total of 914 patients in the trial with known smoking status, 439 (48%) patients were ever smokers (264 current smokers and 175 former smokers). Current and former smokers were younger and more likely to be men. Baseline Glasgow Coma Scale score and initial hematoma size did not vary based on smoking status. Ever smokers had higher rates of thalamic hemorrhage (42% versus 34%) and intraventricular hemorrhage (29% versus 23%); this rate was highest among former smokers versus current smokers (49% versus 35%, respectively). Ever smokers had a higher rate of hematoma expansion in 24 hours (adjusted relative risk [RR] [95% CI], 1.46 [1.08-1.96]) compared with nonsmokers on multivariate analysis. There was no significant difference in the rate of death and disability at 90 days between the 2 groups (adjusted RR [95% CI], 1.18 [0.998-1.40]). Conclusions Our analysis demonstrates cigarette smoking as an independent predictor for hematoma expansion. There was no significant difference in death and disability based on smoking status.

Middle Meningeal Artery Embolization in Adjunction to Surgical Evacuation for Treatment of Subdural Hematomas: A Nationwide Comparison of Outcomes With Isolated Surgical Evacuation.

BACKGROUND AND OBJECTIVES: Surgical evacuation is the standard treatment for chronic subdural hematomas (CSDHs) but is associated with a high risk of recurrence and readmission. Middle meningeal artery embolization (MMAE) is a novel treatment approach which could be performed upfront or in adjunction to surgical evacuation. MMAE studies are limited by small sample sizes. This study aimed to describe and compare outcomes of MMAE in adjunction to surgery with those of surgery alone on a national level. METHODS: The national Vizient Clinical Database was queried by use of a specific validated set of International Classification of Diseases, Tenth Revision codes (October 2018-June 2022). Patients with the diagnosis of nontraumatic CSDH who received MMAE and surgical drainage in the same hospitalization were identified, and their outcomes were compared with isolated surgical drainage. RESULTS: A total of 606 subjects from 156 institutes and 6340 subjects from 369 institutes were included in the MMAE plus surgery (M&S) and surgery groups, respectively. Average length of stay was significantly longer in the M&S group (9.87 vs 7.53 days; P < .01). There was no significant difference in the in-hospital mortality rate (2.8% vs 2.9%), but the complication rate was significantly higher in the M&S group (8.7% vs 5.5%; P < .01). Complications that were significantly more common in the M&S group included aspiration pneumonia, postoperative sepsis, and anesthesia-related. Mean direct costs were significantly higher in the M&S group (28 834 vs 16 292 US dollars; P < .01). The 30-day readmission rate was significantly lower in the M&S group compared with the surgery group (4.2% vs 8.0%; P < .01). CONCLUSION: This analysis of large-scale national data indicates that MMAE performed in adjunction to surgery for treatment of CSDH is associated with higher direct costs, higher complication rates, and longer length of stay but lower readmission rates compared with surgical evacuation alone.

Effect of Chronic Anticoagulation on Outcomes of Endovascular Treatment for Unruptured Intracranial Aneurysms-A Propensity-Matched Multicenter Study.

BACKGROUND AND OBJECTIVES: Endovascular treatment of unruptured intracranial aneurysms (UIAs) in patients receiving anticoagulant medications has not been well studied. Whether long-term anticoagulation (AC) use affects aneurysmal obliteration rates and treatment-related complications is unclear. METHODS: Patients with endovascular treatment for UIA from 4 academic centers were identified and divided into AC and non-AC groups. Periprocedural complications, radiographic and clinical outcomes, and retreatment rates were compared between the 2 groups before and after propensity score matching. RESULTS: The initial cohort consisted of 70 patients in the AC group and 355 in the non-AC group. After one-to-one nearest neighbor propensity matching, 38 pairs of patients were compared for periprocedural complications. The total number of complications were higher in the AC group yet not significant (18.4% vs 5.3%, P = .15). After adding imaging follow-up duration to matched variables, 36 pairs were obtained. There was no significant difference in Raymond-Roy occlusion rate between the 2 groups ( P = .74). However, retreatment rate trended higher in the AC group compared with the non-AC group (22.2% vs 5.6%, P = .09). When clinical follow-up duration was added among matched variables, 26 pairs of cases were obtained for long-term clinical outcomes. There was no significant difference in modified Rankin Scale score between the 2 groups ( P = .61). One-to-many nearest neighbor propensities matched analysis with bigger sample sizes yielded similar results. CONCLUSION: The use of anticoagulants does not affect occlusion rates or long-term outcomes in endovascular treatment of UIAs. Retreatment rates were higher in the AC group; however, this was not statistically significant.

Applications of brain-computer interfaces in neurodegenerative diseases.

Brain-computer interfaces (BCIs) provide the central nervous system with channels of direct communication to the outside world, without having to go through the peripheral nervous system. Neurodegenerative diseases (NDs) are notoriously incurable and burdensome medical conditions that will result in progressive deterioration of the nervous system. The applications of BCIs in NDs have been studied for decades now through different approaches, resulting in a considerable amount of literature in all related areas. In this study, we begin by introducing BCIs and proceed by explaining the principles of BCI-based neurorehabilitation. Then, we go through four specific types of NDs, including amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and spinal muscular atrophy, and review some of the applications of BCIs in the neural rehabilitation of these diseases. We conclude with a discussion of the characteristics, challenges, and future possibilities of research in the field. Going through the uses of BCIs in NDs, we can see that approaches and strategies employed to tackle the wide range of limitations caused by NDs are numerous and diverse. Furthermore, NDs can fall under different categories based on the target area of neurodegeneration and thus require different methods of BCI-based rehabilitation. In recent years, neurotechnology companies have substantially invested in research on BCIs, focusing on commercializing BCIs and bringing BCI-based technologies from bench to bedside. This can mean the beginning of a new era for BCI-based neurorehabilitation, with an anticipated spike in interest among researchers, practitioners, engineers, and entrepreneurs alike.

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.

Trends in the size of treated unruptured intracranial aneurysms over 35 years.

OBJECTIVE: In the absence of clear guidelines and consistent natural history data, the decision to treat unruptured intracranial aneurysms (UIAs) is a matter of some controversy. Currently, decisions are often guided by a consensus of cerebrovascular specialist teams and patient preferences. It is unclear how paradigm-shifting developments in the detection and treatment of UIAs have affected the size of the UIAs that are selected for treatment. Herein, the authors aimed to study potential changes in the average size of the UIAs that were treated over time. They hypothesized that the average size of UIAs that are treated is decreasing over time. METHODS: A systematic search of the literature was performed to identify all studies describing the size of UIAs that were treated using any modality. Scatter diagrams with trend lines were used to plot the size of the aneurysms treated over time and assess for the presence of a potentially significant trend via statistical correlation tests. Subgroup analyses based on type of treatment, country of study, and specialty of the authors were performed. RESULTS: A total of 240 studies including 35,150 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. The mean age of patients was 55.5 years, and 70.7% of the patients were females. There was a significant decrease in the size of treated UIAs over time (Spearman's r = -0.186, p < 0.001), with a 0.71-mm decrease in the average size of treated UIAs every 5 years since 1987 and an annual mean dropping below 7 mm in 2012. This decreasing trend was present in surgically and endovascularly treated UIAs (p < 0.001 for both), in more developed and developing countries (p < 0.001 for both), within neurosurgical and non-neurosurgical specialties (p < 0.001 for both), most prominently in the US (Spearman's r = -0.482, p < 0.001), and less prominently in Europe (Spearman's r = -0.221, p < 0.001) and was not detected in East Asia. CONCLUSIONS: The present study indicates that based on the treated UIA size data published in the literature over the past 35 years, smaller UIAs are being treated over time. This trend is likely driven by safer treatments. However, future studies should elucidate the cost-effectiveness of treating smaller UIAs as well as the possible real-world contribution of this trend in preventing aneurysmal subarachnoid hemorrhage.

Application of Vagus Nerve Stimulation in Spinal Cord Injury Rehabilitation.

Spinal cord injury (SCI) is a prevalent devastating condition causing significant morbidity and mortality, especially in developing countries. The pathophysiology of SCI involves ischemia, neuroinflammation, cell death, and scar formation. Due to the lack of definitive therapy for SCI, interventions mainly focus on rehabilitation to reduce deterioration and improve the patient's quality of life. Currently, rehabilitative exercises and neuromodulation methods such as functional electrical stimulation, epidural electrical stimulation, and transcutaneous electrical nerve stimulation are being tested in patients with SCI. Other spinal stimulation techniques are being developed and tested in animal models. However, often these methods require complex surgical procedures and solely focus on motor function. Vagus nerve stimulation (VNS) is currently used in patients with epilepsy, depression, and migraine and is being investigated for its application in other disorders. In animal models of SCI, VNS significantly improved locomotor function by ameliorating inflammation and improving plasticity, suggesting its use in human subjects. SCI patients also suffer from nonmotor complications, including pain, gastrointestinal dysfunction, cardiovascular disorders, and chronic conditions such as obesity and diabetes. VNS has shown promising results in alleviating these conditions in non-SCI patients, which makes it a possible therapeutic option in SCI patients.