United States regulatory approval of medical devices used for endovascular neurosurgery: A two-decade review of FDA regulatory files.

BACKGROUND: The evolution of neuroendovascular technologies has progressed substantially. Over the last two decades, the introduction of new endovascular devices has facilitated treatment for more patients, and as a result, the regulatory environment concerning neuroendovascular devices has evolved rapidly in response. OBJECTIVE: To examine trends in the approval of neuroendovascular devices by the United States Food and Drug Administration (FDA) over the last 20 years. METHODS: Open-access US FDA databases were queried between January 2000 and December 2022 for all devices approved by the Neurological Devices Advisory Committee. Neuroendovascular devices were manually classified and grouped by category. Device approval data, including approval times, approval pathway, and presence of predicate devices, were examined. RESULTS: A total of 3186 neurological devices were approved via various US FDA pathways during the study period. 320 (10.0%) corresponded to neuroendovascular devices, of which 301 (94.1%) were approved via the 510(k) pathway. The percentage of 510(k) pathway neuroendovascular devices increased from 6.9% to 14.3% of all neuro devices before and after 2015, respectively. There was an increase in approval times for neuroendovascular devices cleared after 2015. CONCLUSION: Over the last two decades, the neuroendovascular device armamentarium has rapidly expanded, especially after positive stroke trials in 2015. Regulatory approval times are significantly affected by device category, generation, company size, and company location, and a vast majority are approved by the 510(k) pathway. These results can guide further innovation in the endovascular device space and may act as a roadmap for future regulatory planning.

Long-term outcomes after responsive neurostimulation for treatment of refractory epilepsy: a single-center experience of 100 cases.

OBJECTIVE: Despite antiepileptic drugs, more than 30% of people with epilepsy continue to have seizures. Patients with such drug-resistant epilepsy (DRE) may undergo invasive treatment such as resection, laser ablation of the epileptogenic focus, or vagus nerve stimulation, but many are not candidates for epilepsy surgery or fail to respond to such interventions. Responsive neurostimulation (RNS) provides a neuromodulatory option. In this study, the authors present a single-center experience with the use of RNS over the last 5 years to provide long-term control of seizures in patients with DRE with at least 1 year of follow-up. METHODS: The authors performed a retrospective analysis of a prospectively collected single-center database of consecutive DRE patients who underwent RNS system implantation from September 2015 to December 2020. Patients were followed-up postoperatively to evaluate seizure freedom and complications. RESULTS: One hundred patients underwent RNS placement. Seven patients developed infections: 2 responded to intravenous antibiotic therapy, 3 required partial removal and salvaging of the system, and 2 required complete removal of the RNS device. No postoperative tract hemorrhages, strokes, device migrations, or malfunctions were documented in this cohort. The average follow-up period was 26.3 months (range 1-5.2 years). In terms of seizure reduction, 8 patients had 0%-24% improvement, 14 had 25%-49% improvement, 29 experienced 50%-74% improvement, 30 had 75%-99% improvement, and 19 achieved seizure freedom. RNS showed significantly better outcomes over time: patients with more than 3 years of RNS therapy had 1.8 higher odds of achieving 75% or more seizure reduction (95% CI 1.07-3.09, p = 0.02). Also, patients who had undergone resective or ablative surgery prior to RNS implantation had 8.25 higher odds of experiencing 50% or more seizure reduction (95% CI 1.05-65.1, p = 0.04). CONCLUSIONS: Responsive neurostimulator implantation achieved 50% or more seizure reduction in approximately 80% of patients. Even in patients who did not achieve seizure freedom, significant improvement in seizure duration, severity, or postictal state was reported in more than 68% of cases. Infection (7%) was the most common complication. Patients with prior resective or ablative procedures and those who had been treated with RNS for more than 3 years achieved better outcomes.

Differences in radiopacity among CT contrast agents and concentrations: A quantitative study.

BACKGROUND AND PURPOSE: Several studies in the literature have attempted to subjectively assess the degree of visualization of different neurovascular structures using different contrast agents and concentrations. Given the recent contrast shortages, we aim to objectively compare the radiopacity achieved with four angiographic contrast agents used in clinical practice. METHODS: Isovue 370, Visipaque 320, Omnipaque 300, and Isovue 300 were each drawn up at 25%, 50%, 75%, and 100% concentrations and compared against normal saline and air syringes. CT scans were obtained, and regions of interest were analyzed for radiopacity using Hounsfield unit (HU) measurements. An aneurysm model with different contrast concentrations was also scanned and dimensions compared. Two-tailed t-tests and Cohen's d coefficients were applied to assess for differences in mean HU measurements. RESULTS: Isovue 370 and Isovue 300 had the highest and lowest mean HU, respectively (p < .001). Visipaque 320 at 25% concentration had the lowest mean HU at -.76. Statistically similar agents (p < .05) were Visipaque 320 and Omnipaque 300 at a 100% concentration (p = .30), and Omnipaque 300 and Isovue 300 at a 25% concentration (p = .73). Aneurysm dimensions among Isovue 370, Visipaque 320, and Omnipaque 300 were all similar, whereas with Isovue 300, the dimensions were significantly smaller (p < .05). CONCLUSION: Isovue 370 provides the highest HU radiopacity and the most accurate aneurysm measurements. Angiographic measurements obtained with Isovue 300 may underestimate the actual aneurysmal dimensions. Visipaque 320 and Omnipaque 300 at 100% concentration have similar mean HUs and are beneficial for patients with chronic kidney or cardiac disease.

Procedural and Clinical Outcome Analysis of Monoplane versus Biplane Angiography Suites in Stroke Thrombectomies.

BACKGROUND: Thrombectomy is now the standard of care in the treatment of acute ischemic stroke caused by emergent large vessel occlusion. Therefore thrombectomy services have expanded from Comprehensive Stroke Centers to Thrombectomy-Capable Stroke Centers. Stroke interventions at these sites are performed in both biplane and monoplane angiography suites. It has been hypothesized that differences in these systems may affect time to successful reperfusion, with a potentially significant effect on neurologic outcomes. With an increase in TSCs, this study aims to evaluate the safety and efficacy of monoplane thrombectomy versus biplane thrombectomy. METHODS: Patients who presented with isolated proximal middle cerebral artery M1 occlusions and underwent endovascular thrombectomy from March 2015 to August 2018 at 5 different centers within a single health system were included. Thrombectomy was performed by the same group of experienced neurointerventionalists. The primary endpoint was functional outcome as measured by the modified Rankin scale at 90 days. Secondary endpoints included recanalization grade as measured by the Thrombolysis in Cerebral Infarction score, time to final reperfusion, and incidence of hemorrhagic conversion. RESULTS: A total of 197 patients were included in this study. Of them, 80.7% underwent thrombectomy on biplane systems. Time to final reperfusion was 10.2 minutes longer in the monoplane group but was not statistically significant (P = 0.252). There was no significant difference in the rates of favorable reperfusion (P = 0.755), hemorrhagic conversion (P = 0.580), or functional outcome at 90 days (favorable modified Rankin Scale 0-2, P = 0.210; favorable modified Rankin Scale 0-3, P = 0.697). CONCLUSION: Despite perceived advantages of biplane systems in reducing procedural time, our study demonstrates no significant differences between systems. These data support the safety and efficacy of performing thrombectomy on monoplane systems and may also carry implications for reducing patient transfer times and potentially increasing thrombectomy access to areas of the world where biplane suites may not be available. The next step would be a prospective randomized trial comparing both systems in different settings.

Contemporary intraoperative visualization for GBM with use of exoscope, 5-ALA fluorescence-guided surgery and tractography.

Maximal safe resection is the primary goal of glioma surgery. By incorporating improved intraoperative visualization with the 3D exoscope combined with 5-ALA fluorescence, in addition to neuronavigation and diffusion tensor imaging (DTI) fiber tracking, the safety of resection of tumors in eloquent brain regions can be maximized. This video highlights some of the various intraoperative adjuncts used in brain tumor surgery for high-grade glioma. In this case, the authors highlight the resection of a left posterior temporal lobe high-grade glioma in a 33-year-old patient, who initially presented with seizures, word-finding difficulty, and right-sided weakness. They demonstrate the multiple surgical adjuncts used both before and during surgical resection, and how multiple adjuncts can be effectively orchestrated to make surgery in eloquent brain areas safer for patients. Patient consent was obtained for publication. The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21174.

Minimally invasive endoscopic approach to perform complete coccygectomy in patients with chronic refractory coccydynia: illustrative case.

BACKGROUND: Coccydynia refers to debilitating pain in the coccygeal region of the spine. Treatment strategies range from conservative measures (e.g., ergonomic adaptations, physical therapy, nerve block injections) to partial or complete removal of the coccyx (coccygectomy). Because the surgical intervention is situated in a high-pressure location close to the anus, a possible complication is the formation of sacral pressure ulcers and infection at the incision site. OBSERVATIONS: In this case report, the authors presented a minimally invasive, fully endoscopic approach to safely perform complete coccygectomy for treatment of refractory posttraumatic coccydynia. LESSONS: Although this is a single case report, the authors hope that this novel endoscopic approach may achieve improved wound healing, reduced infection rates, and lower risk of penetration injury to retroperitoneal organs in patients requiring coccygectomy.

Responsive Neurostimulation of the Thalamus for the Treatment of Refractory Epilepsy.

Introduction: One-third of patients with epilepsy continue to have seizures despite antiepileptic medications. Some of these refractory patients may not be candidates for surgical resection primarily because the seizure onset zones (SOZs) involve both hemispheres or are located in eloquent areas. The NeuroPace Responsive Neurostimulation System (RNS) is a closed-loop device that uses programmable detection and stimulation to tailor therapy to a patient's individual neurophysiology. Here, we present our single-center experience with the use of RNS in thalamic nuclei to provide long-term seizure control in patients with refractory epilepsy. Methods: We performed a prospective single-center study of consecutive refractory epilepsy patients who underwent RNS system implantation in the anterior (ANT) and centromedian (CM) thalamic nuclei from September 2015 to December 2020. Patients were followed postoperatively to evaluate seizure freedom and complications. Results: Twenty-three patients underwent placement of 36 RNS thalamic leads (CM = 27 leads, ANT = 9 leads). Mean age at implant was 18.8 ± 11.2 years (range 7.8-62 years-old). Two patients (8.7%) developed infections: 1 improved with antibiotic treatments alone, and 1 required removal with eventual replacement of the system to recover the therapeutic benefit. Mean time from RNS implantation to last follow-up was 22.3 months. Based on overall reduction of seizure frequency, 2 patients (8.7%) had no- to <25% improvement, 6 patients (26.1%) had 25-49% improvement, 14 patients (60.9%) had 50-99% improvement, and 1 patient (4.3%) became seizure-free. All patients reported significant improvement in seizure duration and severity, and 17 patients (74%) reported improved post-ictal state. There was a trend for subjects with SOZs located in the temporal lobe to achieve better outcomes after thalamic RNS compared to those with extratemporal SOZs. Of note, seizure etiology was syndromic in 12 cases (52.2%), and 7 patients (30.4%) had undergone resection/disconnection surgery prior to thalamic RNS therapy. Conclusion: Thalamic RNS achieved ≥50% seizure control in ~65% of patients. Infections were the most common complication. This therapeutic modality may be particularly useful for patients affected by aggressive epilepsy syndromes since a young age, those whose seizure foci are located in the mesial temporal lobe, and those who have failed prior surgical interventions.

Dural arteriovenous fistulas without cortical venous drainage: presentation, treatment, and outcomes.

OBJECTIVE: Current evidence suggests that intracranial dural arteriovenous fistulas (dAVFs) without cortical venous drainage (CVD) have a benign clinical course. However, no large study has evaluated the safety and efficacy of current treatments and their impact over the natural history of dAVFs without CVD. METHODS: The authors conducted an analysis of the retrospectively collected multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database. Patient demographics and presenting symptoms, angiographic features of the dAVFs, and treatment outcomes of patients with Borden type I dAVFs were reviewed. Clinical and radiological follow-up information was assessed to determine rates of new intracranial hemorrhage (ICH) or nonhemorrhagic neurological deficit (NHND), worsening of venous hyperdynamic symptoms (VHSs), angiographic recurrence, and progression or spontaneous regression of dAVFs over time. RESULTS: A total of 342 patients/Borden type I dAVFs were identified. The mean patient age was 58.1 ± 15.6 years, and 62% were women. The mean follow-up time was 37.7 ± 54.3 months. Of 230 (67.3%) treated dAVFs, 178 (77%) underwent mainly endovascular embolization, 11 (4.7%) radiosurgery alone, and 4 (1.7%) open surgery as the primary modality. After the first embolization, most dAVFs (47.2%) achieved only partial reduction in early venous filling. Multiple complementary interventions increased complete obliteration rates from 37.9% after first embolization to 46.7% after two or more embolizations, and 55.2% after combined radiosurgery and open surgery. Immediate postprocedural complications occurred in 35 dAVFs (15.2%) and 6 (2.6%) with permanent sequelae. Of 127 completely obliterated dAVFs by any therapeutic modality, 2 (1.6%) showed angiographic recurrence/recanalization at a mean of 34.2 months after treatment. Progression to Borden-Shucart type II or III was documented in 2.2% of patients and subsequent development of a new dAVF in 1.6%. Partial spontaneous regression was found in 22 (21.4%) of 103 nontreated dAVFs. Multivariate Cox regression analysis demonstrated that older age, NHND, or severe venous-hyperdynamic symptoms at presentation and infratentorial location were associated with worse prognosis. Kaplan-Meier curves showed no significant difference for stable/improved symptoms survival probability in treated versus nontreated dAVFs. However, estimated survival times showed better trends for treated dAVFs compared with nontreated dAVFs (288.1 months vs 151.1 months, log-rank p = 0.28). This difference was statistically significant for treated dAVFs with 100% occlusion (394 months, log-rank p < 0.001). CONCLUSIONS: Current therapeutic modalities for management of dAVFs without CVD may provide better symptom control when complete angiographic occlusion is achieved.

Postoperative cognitive dysfunction after endovascular treatments for unruptured intracranial aneurysms: A pilot study.

OBJECTIVE: Post operative cognitive dysfunction (POCD) has been widely observed after major surgery, particularly in elderly patients with general anesthesia (GA). However, a specific unanswered question is whether different approaches to anesthetic managements are associated with different cognitive outcomes after endovascular treatments for unruptured intracranial aneurysms (UIAs). The purpose of this study is to assess the correlation of POCD with GA versus monitored anesthesia care (MAC). METHODS: We performed a pragmatic, prospective study to assess the association between different anesthetic approaches and POCD. We compared the pre- and post-procedural Montreal Cognitive Assessment (MoCA) scores in patients with normal cognition who underwent treatments of UIAs with various endovascular methods, using either GA or MAC. RESULTS: A total of 23 patients with UIAs were enrolled in the study. Seven (30.4%) and sixteen (69.6%) UIAs were treated without perioperative complications under GA or MAC, respectively. There was a significant decline in the post-procedural MoCA score under GA (mean difference = 1.14; 95% confidence interval = [0.42-1.87], P < 0.01). By contrast, there was no significant difference of MoCA score between pre- and post-procedure under MAC (mean difference = 0.19; 95% confidence interval = [-0.29-0.67], P = 0.59). CONCLUSIONS: Treating UIAs using MAC was associated with a decrease in POCD as compared to GA in patients undergoing endovascular treatments for UIAs with normal cognition. Larger randomized studies are needed to confirm these findings.

Diagnóstico y tratamiento de la rinosinusitis crónica en adultos. Consenso de expertos: Asociación Colombiana de Otorrinolaringología-2021. / Diagnosis and treatment of chronic rhinosinusitis in adults. Expert consensus: Asociación Colombiana de Otorrinolaringología -2021.

Introducción: la Rinosinusitis Crónica se define como la inflamación crónica de la nariz y los senos paranasales por más de 12 semanas. La prevalencia varía entre el 5% - 30% de acuerdo con la zona geográfica según un estudio de carga de enfermedad (2012-2014), la prevalencia de las enfermedades respiratorias crónicas (rinitis y sinusitis crónica) varió entre el 10% y el 25%. Objetivo: establecer un conjunto de consideraciones basadas en consenso de expertos, para el diagnóstico y el tratamiento de la rinosinusitis crónica en pacientes adultos, en el contexto colombiano. Métodos: se llevó a cabo un consenso formal (Delphi y nominal). Se conformó un grupo de expertos, se definieron el alcance y las preguntas. Se realizaron dos rondas de calificación anónimas, y una discusión para las preguntas sin consenso. En las preguntas con opciones de uno a nueve, se consideró consenso con una mediana de uno a tres o de siete a nueve. En las preguntas tipo Likert, se consideró consenso un porcentaje igual o superior al 80% en acuerdos o desacuerdos. Resultados: se definieron y calificaron 18 preguntas, con la participación de 17 otorrinolaringólogos, de 8 ciudades colombianas, todos miembros de la Asociación Colombiana de Otorrinolaringología y con un promedio de experticia de 19.2 años (Desviación estándar [DE]: 10,2). Se obtuvieron 18 recomendaciones para el diagnóstico y el tratamiento de esta patología. Conclusiones: las recomendaciones emitidas por los expertos permiten orientar y estandarizar el diagnóstico y el tratamiento de la rinosinusitis crónica en adultos, en el contexto de los servicios de salud en Colombia.

Introduction: Chronic Rhinosinusitis is defined as chronic inflammation of the nose and paranasal sinuses for more than 12 weeks. The prevalence varies between 5% - 30% depending on the geographical area according to a disease burden study (2012-2014), the prevalence of chronic respiratory diseases (rhinitis and chronic sinusitis) varied between 10% - 25%. Objective: To establish a set of considerations based on expert consensus, for the diagnosis and treatment of chronic rhinosinusitis in adult patients, in the Colombian context. Methods: A formal consensus (Delphi and nominal) was carried out. A group of experts was formed, the scope and questions were defined. Two anonymous grading rounds were conducted, and a discussion for questions without consensus. In the Questions with options from one to nine were considered consensus with a median of one to three or seven to nine. In the Likert-type questions, a percentage equal to or greater than 80% in agreements or disagreements was considered consensus. Results: 18 questions were defined and scored, with the participation of 17 otorhinolaryngologists, from eight Colombian cities, all members of the Colombian Association of Otorhinolaryngology and with an average experience of 19.2 years (Standard desviation [SD]: 10.2). 18 recommendations were obtained for the diagnosis and treatment of this pathology. Conclusions: The recommendations issued by the experts allow to guide and standardize the diagnosis and treatment of chronic rhinosinusitis in adults, in the context of health services in Colombia.

Importancia de los virus en las exacerbaciones de Enfermedad Pulmonar Obstructiva Crónica (EPOC). ¿Podría cambiar su comportamiento durante la pandemia de SARS-COV-2 (COVID-19)? / Importance of Viruses in Exacerbations of Chronic Obstructive Pulmonary Disease (COPD). Could Change its Behavior During the SARS-COV-2 (COVID-19) pandemic? / Importância dos vírus nas exacerbações da Doença Pulmonar Obstrutiva Crónica (DPOC). Poderia mudar seu comportamento durante a pandemia de SARS-COV-2 (COVID-19)?

Resumen: La pandemia por SARS-COV-2 ha generado muchos interrogantes sobre el comportamiento de enfermedades crónicas. Si bien se conoce que los pacientes con comorbilidades importantes tienen un mayor riesgo de complicaciones, no se conoce el comportamiento de enfermedades, como la enfermedad pulmonar obstructiva crónica (EPOC), en el período de pandemia y cuarentena por COVID-19. En este artículo, se realizó una revisión de la literatura sobre los principales aspectos teóricos para entender las posibles interacciones entre la infección por SARS-COV-2 y pacientes con patología respiratoria como la EPOC. Se revisaron los principales aspectos de las infecciones virales y su fisiopatología en la exacerbación de la enfermedad, sus mecanismos inflamatorios, y las condiciones que pueden aumentar el riesgo de infección y gravedad durante la pandemia por COVID-19. Además, se exploraron los aspectos relacionados a la cuarentena y su posible influencia sobre la exacerbación de la enfermedad. Finalmente, se exploraron los aspectos económicos relacionados con la exacerbación y su manejo asociado a la pandemia.

Abstract: The SARS-COV-2 pandemic has raised many questions about the behavior of chronic diseases. Although it is known that patients with significant comorbidities have a higher risk of complications, the behavior of diseases, such as chronic obstructive pulmonary disease (COPD), during the period of the COVID-19 pandemic and quarantine is not known. In this article, a literature review was carried out on the main theoretical aspects to understand the possible interactions between SARS-COV-2 infection and patients with respiratory pathology such as COPD. The main aspects of viral infections and their pathophysiology in the exacerbation of the disease, their inflammatory mechanisms, and the conditions that can increase the risk of infection and severity during the COVID-19 pandemic were reviewed. In addition, aspects related to quarantine and its possible influence on the exacerbation of the disease were explored. Finally, the economic aspects related to the exacerbation and its management associated with the pandemic were explored.

Resumo: A pandemia de SARS-COV-2 tem gerado muitos questionamentos sobre o comportamento das doenças crônicas. Embora se saiba que pacientes com comorbidades significativas apresentam risco aumentado de complicações, o comportamento de doenças como a doença pulmonar obstrutiva crónica (DPOC) não é conhecido. No período de pandemia e quarentena por COVID-19. Neste artigo, foi realizada urna revisão da literatura sobre os principais aspectos teóricos para compreender as possíveis interações entre a infecção por SARS-COV-2 e pacientes com patologia respiratória, como DPOC. Foram revisados os principais aspectos das infecções virais e sua fisiopatologia na exacerbação da doença, seus mecanismos inflamatórios e as condições que podem aumentar o risco de infecção e gravidade durante a pandemia COVID-19. Além disso, foram explorados aspectos relacionados à quarentena e sua possível influencia na exacerbação da doença. Por fim, foram explorados os aspectos económicos relacionados à exacerbação e sua gestão associada à pandemia.

Dependence of COVID-19 Policies on End-of-Year Holiday Contacts in Mexico City Metropolitan Area: A Modeling Study.

Background. Mexico City Metropolitan Area (MCMA) has the largest number of COVID-19 (coronavirus disease 2019) cases in Mexico and is at risk of exceeding its hospital capacity in early 2021. Methods. We used the Stanford-CIDE Coronavirus Simulation Model (SC-COSMO), a dynamic transmission model of COVID-19, to evaluate the effect of policies considering increased contacts during the end-of-year holidays, intensification of physical distancing, and school reopening on projected confirmed cases and deaths, hospital demand, and hospital capacity exceedance. Model parameters were derived from primary data, literature, and calibrated. Results. Following high levels of holiday contacts even with no in-person schooling, MCMA will have 0.9 million (95% prediction interval 0.3-1.6) additional COVID-19 cases between December 7, 2020, and March 7, 2021, and hospitalizations will peak at 26,000 (8,300-54,500) on January 25, 2021, with a 97% chance of exceeding COVID-19-specific capacity (9,667 beds). If MCMA were to control holiday contacts, the city could reopen in-person schools, provided they increase physical distancing with 0.5 million (0.2-0.9) additional cases and hospitalizations peaking at 12,000 (3,700-27,000) on January 19, 2021 (60% chance of exceedance). Conclusion. MCMA must increase COVID-19 hospital capacity under all scenarios considered. MCMA's ability to reopen schools in early 2021 depends on sustaining physical distancing and on controlling contacts during the end-of-year holiday.

Availability and Readability of Spinal Cord Injury Online Information Materials for Spanish Speaking Population in Neurosurgical Academic Programs: A Nationwide Study.

BACKGROUND: Recent publications have demonstrated that information has been transmitted inappropriately to the lay person in different pathologies. This limitation is also observed in Spanish language. We evaluate the availability and readability of online patient education material (PEM) on spinal cord injury (SCI) information for the Spanish-speaking population from academic neurosurgery residency programs in the United States. METHODS: This is a descriptive analysis of online SCI PEM from neurosurgical residency programs websites. We assess the availability of information in Spanish using a modification of a previously published classification. To assess accessibility, we calculated the time spent and the number of clicks to find the information in Spanish. We calculated the readability of the material using the "Indice Flesch-Szigriszt" (INFLESZ), which determines the difficulty of readability of health-related material in Spanish. RESULTS: A total of 116 accredited neurosurgery residency programs comprised our cohort. Ten (9%) programs had available "mirrored" information in Spanish from its original version in English, 9 (8.1%) used a translation software, 79 (71.2%) provide interpreter services, and 3 (2%) did not have written information or information about translation services. A mean of 72.9 seconds (SD +/- 71.2) were required to have access to the Spanish information or contact information for translation services. Twelve (57.1%) websites with written Spanish information had an INFLESZ score above 55.00, which translates as an appropriate readability level for the general population. CONCLUSIONS: More than half of the academic neurosurgery programs or affiliated hospital websites do not provide written informative material about SCI in Spanish. When available, the information is not always transmitted with a level of readability appropriate for the layperson. Most of the websites provide translation or interpreter services that are not directly related to SCI.

Semiautomated 3D mapping of aneurysmal wall enhancement with 7T-MRI.

Aneurysm wall enhancement (AWE) after the administration of contrast gadolinium is a potential biomarker of unstable intracranial aneurysms. While most studies determine AWE subjectively, this study comprehensively quantified AWE in 3D imaging using a semi-automated method. Thirty patients with 33 unruptured intracranial aneurysms prospectively underwent high-resolution imaging with 7T-MRI. The signal intensity (SI) of the aneurysm wall was mapped and normalized to the pituitary stalk (PS) and corpus callosum (CC). The CC proved to be a more reliable normalizing structure in detecting contrast enhancement (p < 0.0001). 3D-heatmaps and histogram analysis of AWE were used to generate the following metrics: specific aneurysm wall enhancement (SAWE), general aneurysm wall enhancement (GAWE) and focal aneurysm wall enhancement (FAWE). GAWE was more accurate in detecting known morphological determinants of aneurysm instability such as size ≥ 7 mm (p = 0.049), size ratio (p = 0.01) and aspect ratio (p = 0.002). SAWE and FAWE were aneurysm specific metrics used to characterize enhancement patterns within the aneurysm wall and the distribution of enhancement along the aneurysm. Blebs were easily identified on 3D-heatmaps and were more enhancing than aneurysm sacs (p = 0.0017). 3D-AWE mapping may be a powerful objective tool in characterizing different biological processes of the aneurysm wall.

Aneurysm Wall Enhancement Is Associated With Decreased Intrasaccular IL-10 and Morphological Features of Instability.

BACKGROUND: High-resolution vessel wall imaging plays an increasingly important role in assessing the risk of aneurysm rupture. OBJECTIVE: To introduce an approach toward the validation of the wall enhancement as a direct surrogate parameter for aneurysm stability. METHODS: A total of 19 patients harboring 22 incidental intracranial aneurysms were enrolled in this study. The aneurysms were dichotomized according to their aneurysm-to-pituitary stalk contrast ratio using a cutoff value of 0.5 (nonenhancing < 0.5; enhancing ≥ 0.5). We evaluated the association of aneurysm wall enhancement with morphological characteristics, hemodynamic features, and inflammatory chemokines directly measured inside the aneurysm. RESULTS: Differences in plasma concentration of chemokines and inflammatory molecules, morphological, and hemodynamic parameters were analyzed using the Welch test or Mann-Whitney U test. The concentration ΔIL-10 in the lumen of intracranial aneurysms with low wall enhancement was significantly increased compared to aneurysms with strong aneurysm wall enhancement (P = .014). The analysis of morphological and hemodynamic parameters showed significantly increased values for aneurysm volume (P = .03), aneurysm area (P = .044), maximal diameter (P = .049), and nonsphericity index (P = .021) for intracranial aneurysms with strong aneurysm wall enhancement. None of the hemodynamic parameters reached statistical significance; however, the total viscous shear force computed over the region of low wall shear stress showed a strong tendency toward significance (P = .053). CONCLUSION: Aneurysmal wall enhancement shows strong associations with decreased intrasaccular IL-10 and established morphological indicators of aneurysm instability.

High-resolution vessel wall imaging after mechanical thrombectomy.

OBJECTIVES: High-resolution magnetic resonance imaging has the potential of characterising arterial wall changes after endovascular mechanical thrombectomy. The purpose of this study is to evaluate high-resolution magnetic resonance imaging features of large intracranial arteries following mechanical thrombectomy. METHODS: Patients who presented with acute ischaemic stroke due to large vessel occlusion and underwent mechanical thrombectomy were prospectively recruited. Subjects underwent high-resolution magnetic resonance imaging within 24 hours of the procedure. Magnetic resonance imaging sequences included whole brain T1 pre and post-contrast black-blood imaging, three-dimensional T2, contrast-enhanced magnetic resonance angiography and susceptibility-weighted imaging. Arterial wall enhancement was objectively assessed after normalisation with the pituitary stalk. The contrast ratio of target vessels was compared with non-affected reference vessels. RESULTS: Twenty patients with 22 target vessels and 20 reference vessels were included in the study. Sixteen patients were treated with stentriever with or without aspiration, and four with contact aspiration only. Significantly higher arterial wall enhancement was identified on the target vessel when compared to the reference vessel (U = 22.5, P < 0.01). The stentriever group had an 82% increase in the contrast ratio of the target vessel (x̄ = 0.75 ± 0.21) when compared to the reference vessel (x̄ = 0.41 ± 0.13), whereas the contact aspiration group had a 64% increase of the contrast ratio difference between target (x̄ = 0.62 ± 0.07) and reference vessels (x̄ = 0.38 ± 0.12). Approximately 65% of patients in the stentriever group had a positive parenchymal susceptibility-weighted imaging versus 25% in the contact aspiration group. There was no statistically significant correlation between susceptibility-weighted imaging volume and the percentage increase in the contrast ratio (rs = 0.098, P = 0.748). CONCLUSIONS: This prospective pilot study used the objective quantification of arterial wall enhancement in determining arterial changes after mechanical thrombectomy. Preliminary data suggest that the use of stentrievers is associated with a higher enhancement as compared to reperfusion catheters.

Insights into the pathogenesis of cerebral fusiform aneurysms: high-resolution MRI and computational analysis.

BACKGROUND: Intracranial fusiform aneurysms are complex and poorly characterized vascular lesions. High-resolution magnetic resonance imaging (HR-MRI) and computational morphological analysis may be used to characterize cerebral fusiform aneurysms. OBJECTIVE: To use advanced imaging and computational analysis to understand the unique pathophysiology, and determine possible underlying mechanisms of instability of cerebral fusiform aneurysms. METHODS: Patients with unruptured intracranial aneurysms prospectively underwent imaging with 3T HR-MRI at diagnosis. Aneurysmal wall enhancement was objectively quantified using signal intensity after normalization of the contrast ratio (CR) with the pituitary stalk. Enhancement between saccular and fusiform aneurysms was compared, as well as enhancement characteristics of fusiform aneurysms. The presence of microhemorrhages in fusiform aneurysms was determined with quantitative susceptibility mapping (QSM). Three distinct types of fusiform aneurysms were analyzed with computational fluid dynamics (CFD) and finite element analysis (FEA). RESULTS: A total of 130 patients with 160 aneurysms underwent HR-MRI. 136 aneurysms were saccular and 24 were fusiform. Fusiform aneurysms had a significantly higher CR and diameter than saccular aneurysms. Enhancing fusiform aneurysms exhibited more enhancement of reference vessels than non-enhancing fusiform aneurysms. Ten fusiform aneurysms underwent QSM analysis, and five aneurysms showed microhemorrhages. Microhemorrhage-positive aneurysms had a larger volume, diameter, and greater enhancement than aneurysms without microhemorrhage. Three types of fusiform aneurysms exhibited different CFD and FEA patterns. CONCLUSION: Fusiform aneurysms exhibited more contrast enhancement than saccular aneurysms. Enhancing fusiform aneurysms had larger volume and diameter, more enhancement of reference vessels, and more often exhibited microhemorrhage than non-enhancing aneurysms. CFD and FEA suggest that various pathophysiological processes determine the formation and growth of fusiform aneurysms.

Concentration of Lp(a) (Lipoprotein[a]) in Aneurysm Sac Is Associated With Wall Enhancement of Unruptured Intracranial Aneurysm.

BACKGROUND AND PURPOSE: Atherosclerotic remodeling of the aneurysm wall, which could be detected as aneurysm wall enhancement (AWE) by magnetic resonance-vessel wall imaging, is a part of degenerative change of unruptured intracranial aneurysms (UIAs). The purpose of this study was to determine whether the luminal concentrations of atherosclerotic proteins in the aneurysm sac were associated with increased wall enhancement of UIAs in vessel wall imaging. METHODS: We performed a prospective study of subjects undergoing endovascular treatments for UIAs. All subjects underwent evaluation using 3T-magnetic resonance imaging, including pre/postcontrast vessel wall imaging of the UIAs. Blood samples were collected from the aneurysm sac and the parent artery during endovascular procedures. Presence/absence of AWE was correlated with the delta difference in concentration for each atherosclerotic protein between the lumen of UIA and in the parent artery. RESULTS: A total of consecutive 17 patients with 19 UIAs were enrolled. The delta difference of lipoprotein(a) was significantly higher in UIAs with AWE compared with those without AWE (-6.9±16.0 versus -45.4±44.9 µg/mL, P=0.03). CONCLUSIONS: Higher luminal concentrations of lipoprotein(a) in the aneurysm sac were significantly associated with increased wall enhancement of UIAs. A larger study is needed to confirm these findings.

Performance of Aneurysm Wall Enhancement Compared with Clinical Predictive Scales: PHASES, ELAPSS, and UIATS.

OBJECTIVE: To correlate the presence of objectively measured wall enhancement on high-resolution vessel wall imaging (HR-VWI) with the clinical predictive scales PHASES, ELAPSS, and UIATS. METHODS: Patients with unruptured intracranial aneurysm (UIAs) prospectively underwent HR-VWI on a 3-T magnetic resonance imaging scanner at diagnosis. Aneurysmal wall enhancement was objectively quantified on T1 postcontrast magnetic resonance imaging using signal intensity values adjusted for the pituitary stalk to calculate a contrast ratio (CRstalk). UIAs with CRstalk ≥0.60 were considered "enhancing." Patients' demographics, comorbidities, and aneurysm morphology were reviewed to calculate PHASES, ELAPSS, and UIATS scores. Pearson coefficients were applied for statistical correlation. Univariable and multivariable logistic regressions were performed to assess for confounders. RESULTS: One-hundred and twenty-three patients harboring 178 UIAs underwent HR-VWI. A total of 101 patients with 135 UIAs were analyzed. Enhancing UIAs were larger (8.4 ± 5.5 mm vs. 5.5 ± 2.3 mm; P < 0.001), had higher aspect ratio (2.3 ± 1.5 vs. 1.8 ± 0.7; P = 0.008), higher size ratio (3.0 ± 1.8 vs. 2.4 ± 1.1; P = 0.016), scored higher on PHASES (5.6 ± 3.9 vs. 4.4 ± 2.6; P = 0.04) and ELAPSS (19.4 ± 8.9 vs. 15.4 ± 7.3; P = 0.006) compared with nonenhancing UIAs. Treatment allocation as defined by UIATS was measured independently to enhancement status. No significant differences were found for UIATS between enhancing and nonenhancing UIAs (P = 0.63). Multivariable regression showed that size was the only independent factor significantly associated with UIA enhancement (odds ratio, 1.76; P = 0.005). CONCLUSIONS: Enhancing UIAs score higher in PHASES and ELAPSS scales. This association is largely explained by aneurysm size, aspect, and size ratios. Morphologic UIA features should be accounted for in clinical predictive scales of aneurysm instability.

Quantitative Assessment of Ventriculostomy-Related Hemorrhage: A Volume-Based Classification System to Predict New Neurological Symptoms.

BACKGROUND: Hemorrhage is one of the most feared complications following ventriculostomy placement. Current studies have assessed factors associated with increased risk of ventriculostomy-related hemorrhage (VRH). However, the clinical significance of VRH has not been determined. OBJECTIVE: To correlate quantitative volumetric measurements of VRH with new neurological symptoms. METHODS: A retrospective review of our institutional database of ventriculostomy patients during the last decade was performed. Patients' demographics and procedural details such as indication, number of passes and position of the catheter were recorded. VRH volume was quantified on noncontrast head computed tomography using the Picture Archiving Communication System (Carestream Vue®, Rochester, New York) semi-automated livewire segmentation tool. Patients with new neurological symptoms within 48 h of VRH were considered symptomatic. Several clinical confounders were ruled out. Logistic regression analyses were performed. The best volumetric cut-offs in predicting symptomatic VRH were determined through receiver operating characteristic (ROC) curve analysis. RESULTS: A total of 3090 patients underwent ventriculostomy procedures and 179 (∼6%) developed VRH. A total of 41 (1.06%) patients with VRH developed new neurological symptoms. Only 12 (0.39%) were attributable to a new VRH. Multivariable logistic regression showed that volume of the hemorrhage (OR 1.17, P = .006) is the only significant predictor of symptomatic VRH. ROC curve analysis demonstrated that VRH volume <1.10 cc has 91.7% sensitivity to rule out symptomatic VRH, whereas a volume >7.59 cc has 95.5% specificity to predict symptomatic VRH. CONCLUSION: Approximately 6% of patients developed postprocedural VRH, but only 0.4% were symptomatic. VRH volumes <1 cc are extremely unlikely to become symptomatic, whereas volumes >7.5 cc may predict development of new neurological deficits.