Clinical outcomes of first- and second-generation hydrogel coils compared with bare platinum coils: a systematic literature review.

Endovascular coiling has revolutionized intracranial aneurysm treatment; however, recurrence continues to represent a major limitation. The hydrogel coil was developed to increase packing density and improve neck healing and therefore decrease recurrence rates. In this paper, we review treatment outcomes of first- (1HCs) and second-generation (2HCs) hydrogel coils and compare them to those of bare platinum coils (BPC). A query of multiple databases was performed. Articles with at least 10 aneurysms treated with either 1HC or 2HC were selected for analysis. Collected data included aneurysm size, rupture status, initial occlusion, initial residual neck/aneurysm, packing density, mortality, morbidity, recurrence, and retreatment rates. The primary endpoint was recurrence at final follow-up. Secondary endpoints included residual neck and dome rates as well as procedure-related complications and functional dependence at final follow-up. Studies that compared 1HC to BPC showed significant lower recurrence (24% vs. 30.8%, p = 0.02) and higher packing density (58.5% vs. 24.1%, p < 0.001) in 1HC but no significant difference in initial occlusion rate (p = 0.08). Studies that compared 2HC to BPC showed lower recurrence (6.3% vs. 14.3%, p = 0.007) and retreatment rates (3.4% vs. 7.7%, p = 0.010) as well as higher packing density (36.4% vs. 29.2%, p = 0.002) in 2HC, with similar initial occlusion rate (p = 0.86). The rate of complications was not statistically different between HC (25.5%) and BPC (22.6%, p = 0.06). Based on our review, the 1HC and 2HC achieved higher packing density and lower recurrence rates compared to BPC. The safety profile was similar between both groups.

New generation Hydrogel Endovascular Aneurysm Treatment Trial (HEAT): a study protocol for a multicenter randomized controlled trial.

PURPOSE: Aneurysm recanalization constitutes a limitation in the endovascular treatment of intracranial aneurysms using conventional bare platinum coils. The development of platinum coils coupled with hydrogel polymers aimed at decreasing the rates of recurrence by way of enhanced coil packing density and biological healing within the aneurysm. While enhanced occlusion and durability has been shown for the first generation hydrogel coils, their use was limited by technical challenges. Less data is available regarding the second-generation hydrogel coils which have been designed to perform like bare platinum coils. METHODS: The new generation Hydrogel Endovascular Aneurysm Treatment Trial (HEAT) is a multicenter, randomized controlled trial that compares the health outcomes of the second-generation HydroCoil Embolic System with bare platinum coils in the endovascular intracranial aneurysms. The primary endpoint is aneurysm recurrence, defined as any progression on the Raymond aneurysm scale, over a 24-month follow-up period. Secondary endpoints include packing density, functional independence, procedural adverse events, mortality rate, initial complete occlusion, aneurysm retreatment, hemorrhage from treated aneurysm, and any aneurysm recurrence. RESULTS: Patient recruitment initiated in June 2011 and ended in January 2016 in 46 centers. Six hundred eligible patients diagnosed with an intracranial aneurysm, ruptured or unruptured were randomly assigned to one of the two treatment arms. CONCLUSION: The HEAT trial compares the durability, imaging, and clinical outcomes of the second-generation hydrogel versus bare platinum coils in the endovascular treatment of ruptured or unruptured intracranial aneurysms. The results of this trial may further inform current endovascular treatment guidelines based on observed long-term outcomes.

Cerebral arteriovenous malformation: complex 3D hemodynamics and 3D blood flow alterations during staged embolization.

Complex hemodynamics in cerebral arteriovenous malformations (AVM) are thought to play a key role in their pathophysiology. We applied 4D flow magnetic resonance imaging (MRI) for the detailed evaluation of AVM function at baseline and to investigate the impact of staged embolization on AVM hemodynamics in a patient with a Spetzler-Martin grade III AVM. The patient underwent three embolization procedures resulting in >50% nidal casting and obliteration of several arteriovenous fistulae. 4D flow MRI demonstrated highly complex 3D hemodynamics at baseline and revealed intricate arterial feeding, a large vascularized nidus with high variability in regional blood flow velocities, and clearly visible venous drainage with high flow velocities above 50 cm/s. 3D blood flow visualization and quantification during follow-up illustrated the systemic impact of focal embolization on cerebral hemodynamics resulting in compaction of the AVM, redistribution of blood flow velocities, and altered peak flow velocities and blood flow in multiple vascular territories. 4D flow MRI may offer a useful noninvasive tool to help to identify subtleties and nuances of the quantitative hemodynamic alterations in AVM vascular architecture as a supplement to established imaging modalities.

Cerebrospinal Venous Fistula Presenting with Cognitive Decline: Systematic Literature Review and Report of Two Cases.

OBJECTIVE: A cerebrospinal fluid (CSF) venous fistula (CVF) is an aberrant connection between the subarachnoid space and a vein resulting in CSF loss. The presentation and management of CVF with cognitive decline is incompletely understood. METHODS: A systematic review was completed following the PRISMA guidelines. Articles that included at least 1 case of imaging-confirmed CVF with details on patient treatment were included. A separate review of cases of patients with spontaneous intracranial hypotension (SIH) with frontotemporal dementia (FTD) or dementia symptoms was also completed. RESULTS: Ten CVF articles (69 patients; average age, 51.5 years) and 5 SIH with FTD or dementia articles (n = 41; average age, 55.9 years) were identified. Only 1 patients with CVF with cognitive abnormalities was identified. The most common symptom was headache in both reviews. Brain sag was identified in all patients, whereas CSF leak was identified in only 2 patients with SIH with FTD or dementia (4.9%). An epidural blood or fibrin glue patch was used in all patients with CVF and in 33 patients with SIH with FTD or dementia. Fifty-five patients with CVF (79.7%) and 27 patients with SIH with FTD or dementia (65.9%) had surgery. CONCLUSIONS: The 2 cases and literature reviews show the difficulty in diagnosis and treatment of CVF with cognitive decline. Novel imaging techniques should be used in patients with cognitive decline in whom a CSF leak is suspected. Transvenous embolization or surgery should be considered before patching for treatment of CVF-induced brain sag and resulting dementia.

Predictive Model Evaluating Risk of Hemorrhage in Intracranial Aneurysms: Analysis from Prospectively Collected HEAT Trial Database.

OBJECTIVE: We analyzed the data of patients enrolled in the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to develop and validate a model to predict the risk of aneurysmal hemorrhage. METHODS: Analysis included data from 600 patients enrolled for the HEAT trial and included single saccular aneurysms of 3-14 mm size. Baseline characteristics were compared between patients with ruptured and unruptured aneurysms. Regression analysis was performed in the training set to identify significant risk factors and was validated in the validation dataset. The complete dataset was used to formulate a scoring model in which positive and negative predictors were assigned 1 and -1 points, respectively. RESULTS: Data from 593 patients were analyzed in which 169 (28.5%) patients had ruptured aneurysms. The training (n = 297) and validation dataset (n = 296) had a comparable proportion of ruptured aneurysms (29.3% and 27.7%). Dome-to-neck ratio >2.5 (odds ratio [OR] 3.66), irregular shape (OR 3.79), daughter sac (OR 5.89), and anterior and posterior communicating artery locations (OR 3.32 and 3.56, respectively) had a higher rupture rate. Use of aspirin was associated with lower risk of hemorrhage (OR 0.16). The area under the curve from the receiver operating curve analysis was 0.88, 0.87, and 0.87 in the training, validation, and combined data set, respectively. The scoring model created a score of -1 to 2, yielding an of aneurysmal hemorrhage probability from 1.5% (score -1) to 70% (score 2). CONCLUSIONS: This prospective study identifies dome-to-neck ratio >2.5, irregular shape, presence of daughter sac, absence of aspirin use, and aneurysm location at anterior communicating and posterior communicating artery as factors associated with increased risk of hemorrhagic presentation in small- to medium-sized intracranial aneurysms. Our model provides an estimate of rupture risk based on the presence or absence of these factors.

Image-localized biopsy mapping of brain tumor heterogeneity: A single-center study protocol.

Brain cancers pose a novel set of difficulties due to the limited accessibility of human brain tumor tissue. For this reason, clinical decision-making relies heavily on MR imaging interpretation, yet the mapping between MRI features and underlying biology remains ambiguous. Standard (clinical) tissue sampling fails to capture the full heterogeneity of the disease. Biopsies are required to obtain a pathological diagnosis and are predominantly taken from the tumor core, which often has different traits to the surrounding invasive tumor that typically leads to recurrent disease. One approach to solving this issue is to characterize the spatial heterogeneity of molecular, genetic, and cellular features of glioma through the intraoperative collection of multiple image-localized biopsy samples paired with multi-parametric MRIs. We have adopted this approach and are currently actively enrolling patients for our 'Image-Based Mapping of Brain Tumors' study. Patients are eligible for this research study (IRB #16-002424) if they are 18 years or older and undergoing surgical intervention for a brain lesion. Once identified, candidate patients receive dynamic susceptibility contrast (DSC) perfusion MRI and diffusion tensor imaging (DTI), in addition to standard sequences (T1, T1Gd, T2, T2-FLAIR) at their presurgical scan. During surgery, sample anatomical locations are tracked using neuronavigation. The collected specimens from this research study are used to capture the intra-tumoral heterogeneity across brain tumors including quantification of genetic aberrations through whole-exome and RNA sequencing as well as other tissue analysis techniques. To date, these data (made available through a public portal) have been used to generate, test, and validate predictive regional maps of the spatial distribution of tumor cell density and/or treatment-related key genetic marker status to identify biopsy and/or treatment targets based on insight from the entire tumor makeup. This type of methodology, when delivered within clinically feasible time frames, has the potential to further inform medical decision-making by improving surgical intervention, radiation, and targeted drug therapy for patients with glioma.

Microsurgical Clipping of a Postcoiling, Residual or Recurrent, Ruptured Anterior Communicating Artery Aneurysm.

Endovascular treatment modalities for intracranial aneurysms have seen a significant increase in popularity since the initial advent of the Guglielmi detachable coils in the early nineties.1 The publication of the International Subarachnoid Aneurysm Trial (ISAT) in addition to significant improvement in catheter and coil technology further cemented the endovascular-first approach, specifically for ruptured aneurysms.2 However, the increase in aneurysm coiling also led to a heightened awareness of its shortcomings, namely a significantly greater rate of recurrence and need for retreatment.3 The Cerebral Aneurysm Rerupture After Treatment (CARAT) study revealed that even though the rate of rerupture is low with both microsurgical and endovascular treatment modalities, the rate of rerupture is greater with incomplete versus complete aneurysm occlusion.4 Previously coiled aneurysms can be challenging to treat. While in some cases further endovascular therapies can be performed, microsurgical clipping remains a compelling alternative, specifically for small recurrent or residual ruptured aneurysms. However, microsurgical clipping of previously coiled aneurysms presents its own set of unique challenges. The presence of coils in the aneurysms increases the complexity of clip reconstruction. In addition, coil extrusion, which is often misdiagnosed as coil compaction on diagnostic imaging and therefore underreported, can further increase the risk of microsurgical dissection. In this operative video, we present a case of a postcoiling, residual or recurrent, ruptured anterior communicating artery aneurysm successfully treated through microsurgical clipping. The patient consented to the procedure as shown in this operative video (Video 1) and gave informed written consent for use of her images in publication.

Awake Resection of an Arteriovenous Malformation.

Arteriovenous malformations (AVMs) are a highly complex array of abnormal arteries and veins that directly fistulize without intervening capillary beds.1 As AVMs can differ in size, location, and morphology, specific clinical management is determined for each individual patient, in conjunction with their specific goals and needs.2 This Video demonstrates the resection of an AVM located in the language area of eloquent cortex of a 38-year-old opera singer. The patient presented to the emergency department with a new-onset seizure. Magnetic resonance imaging including task-based functional imaging demonstrated a left post temporal AVM with associated hemosiderin-stained white matter and language activation just posterior to the lesion. Awake microsurgical resection was recommended given her career as an opera singer and the high-risk location of the AVM in proximity to eloquent language cortex, with additional goals of preventing further risk of hemorrhage and reduction in the risk of epilepsy. The patient underwent a left temporoparietal craniotomy with direct electrical stimulation-based language mapping and monitoring along with microsurgical resection of the AVM with image guidance, confirmed with intraoperative indocyanine green angiography. Postoperative angiography demonstrated no residual AVM with preservation of normal arterial and venous anatomy. At follow-up, the patient was clinically intact, seizure free, and off all antiepileptic medications. At 3 months, she resumed her career as an opera singer. Awake resection with intraoperative functional mapping can be used for select small AVMs to avoid injury to functional tissue and allow more aggressive resection of potentially epileptogenic tissue.

Intracranial Aneurysms in Loeys-Dietz Syndrome: A Multicenter Propensity-Matched Analysis.

BACKGROUND: Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder characterized by a classic triad of hypertelorism, bifid uvula and/or cleft palate, and generalized arterial tortuosity. There are limited data on the prevalence and rupture risk of intracranial aneurysms (IAs) in the setting of LDS, with no established guidelines. OBJECTIVE: To analyze the prevalence and rupture risk of IA in LDS. METHODS: Electronic medical records of patients with a confirmed diagnosis of LDS and available cerebrovascular imaging were reviewed. Patients were divided into 2 groups based on the presence of IA. Unmatched and propensity-matched analyses were used to identify potential risk factors for aneurysm formation. RESULTS: Records of 1111 patients were screened yielding a total of 60 patients with a diagnosis of LDS. Eighteen (30%) patients had IA, 4 (22.2%) of whom had multiple aneurysms for a total of 24 IAs. Twenty-three (95.8%) aneurysms were located in the anterior circulation; none of them were ruptured. On unmatched analysis, age ( P = .015), smoking history ( P = .034), hypertension ( P = .035), and number of extracranial aneurysms ( P < .001) were significantly higher in patients with IA. After matching for age, sex, race, stroke history, family history, and extracranial aneurysms, smoking history ( P = .009) remained significant. CONCLUSION: Patients with LDS have an increased risk of IAs, especially with a history of smoking. The prevalence rate of IAs in our series was 30%. Screening imaging should be considered at diagnosis, and patients should be encouraged to abstain from smoking. Further studies are needed to elucidate the risk of IA rupture and treatment considerations in this unique population.

A comparison of treating physician versus independent core lab assessments of post-aneurysm treatment imaging outcomes: an analysis of prospectively collected data from a randomized trial.

OBJECTIVE: Aneurysm occlusion has been used as surrogate marker of aneurysm treatment efficacy. Aneurysm occlusion scales are used to evaluate the outcome of endovascular aneurysm treatment and to monitor recurrence. These scales, however, require subjective interpretation of imaging data, which can reduce the utility and reliability of these scales and the validity of clinical studies regarding aneurysm occlusion rates. Use of a core lab with independent blinded reviewers has been implemented to enhance the validity of occlusion rate assessments in clinical trials. The degree of agreement between core labs and treating physicians has not been well studied with prospectively collected data. METHODS: In this study, the authors analyzed data from the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to assess the interrater agreement between the treating physician and the blinded core lab. The HEAT trial included 600 patients across 46 sites with intracranial aneurysms treated with coiling. The treating site and the core lab independently reviewed immediate postoperative and follow-up imaging (3-12 and 18-24 months, respectively) using the Raymond-Roy occlusion classification (RROC) scale, Meyer scale, and recanalization survey. A post hoc analysis was performed to calculate interrater reliability using Cohen's kappa. Further analysis was performed to assess whether degree of agreement varied on the basis of various factors, including scale used, timing of imaging, size of the aneurysm, imaging modality, location of the aneurysm, dome-to-neck ratio, and rupture status. RESULTS: Minimal interrater agreement was noted between the core lab reviewers and the treating physicians for assessing aneurysm occlusion using the RROC grading scale (k = 0.39, 95% CI 0.38-0.40) and Meyer scale (k = 0.23, 95% CI 0.14-0.38). The degree of agreement between groups was slightly better but still weak for assessing recanalization (k = 0.45, 95% CI 0.38-0.52). Factors that significantly improved degree of agreement were scales with fewer variables, greater time to follow-up, imaging modality (digital subtraction angiography), and wide-neck aneurysms. CONCLUSIONS: Assessment of aneurysm treatment outcome with commonly used aneurysm occlusion scales suffers from risk of poor interrater agreement. This supports the use of independent core labs for validation of outcome data to minimize reporting bias. Use of outcome tools with fewer point categories is likely to provide better interrater reliability. Therefore, the outcome assessment tools are ideal for clinical outcome assessment provided that they are sensitive enough to detect a clinically significant change.

Moyamoya disease: functional and neurocognitive outcomes in the pediatric and adult populations.

OBJECT: Moyamoya disease is an occlusive cerebrovascular disorder commonly resulting in neurocognitive impairment. The cognitive outcome parameters commonly affected are intelligence, memory, executive function, and quality of life. In this paper, the authors review the existing literature on cognitive and clinical outcomes in adult and pediatric moyamoya populations separately. METHODS: A systematic review of the cognitive and clinical outcome literature was performed using the PubMed/MEDLINE database. Outcomes data were contrasted between adult and pediatric populations. RESULTS: Intelligence is the main cognitive outcome parameter affected in pediatric patients with moyamoya disease, whereas adults most commonly suffer from executive function impairment. Memory has not been studied sufficiently in pediatric patients, and its dysfunction in the adult population remains controversial. Quality of life has not been studied appropriately in either population. Surgical revascularization is the only beneficial treatment option, and a combination of direct and indirect bypass techniques has shown benefit, but the impact on the above-mentioned parameters has not been sufficiently elucidated. CONCLUSIONS: Moyamoya disease affects the cognition and daily function in pediatric patients to a greater extent than in adult patients. Due to the rarity of the disease, there is a distinct lack of high-level evidence regarding cognitive and clinical outcomes.

Moyamoya disease: a review of histopathology, biochemistry, and genetics.

OBJECT: Moyamoya disease (MMD) is a rare cerebrovascular disorder involving stenosis of the major vessels of the circle of Willis and proximal portions of its principal branches. Despite concerted investigation, the pathophysiology of the disorder has not been fully elucidated. Currently, the major proteins believed to play an active role in the pathogenesis include vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), transforming growth factor-ß1 (TGFß1), and granulocyte colony-stimulating factor (G-CSF). In terms of the genetics, recent literature suggests a low penetrance autosomal dominant or polygenic mode of transmission involving chromosomes 3, 6, 8, 12, and 17 for familial MMD. This review summarizes the current knowledge on the histopathology, pathophysiology and genetics of MMD. METHODS: A PubMed/Medline systematic study of the literature was performed, from which 45 articles regarding MMD pathophysiology were identified and analyzed. CONCLUSIONS: Moyamoya disease is characterized by the intimal thickening and media attenuation of the proximal vessels of the circle of Willis as well as the development of an aberrant distal vascular network. The primary proteins that are currently implicated in the pathophysiology of MMD include VEGF, bFGF, HGF, TGFß1, and G-CSF. Furthermore, the current literature on familial MMD has pointed to a low penetrance autosomal dominant or polygenic mode of transmittance at loci on chromosomes 3, 6, 8, 12, and 17.

Endovascular stroke therapy: a single-center retrospective review.

OBJECT: Endovascular treatment of acute ischemic stroke delivers direct therapy at the site of an occluded cerebral artery and can be employed beyond the 3-4.5-hour window limit set for intravenous recombinant tissue plasminogen activator. In this paper, the authors report their experience with various endovascular therapies in acute ischemic stroke. METHODS: The authors conducted a retrospective review of their clinical database for acute ischemic stroke in large-vessel cerebral territories that underwent endovascular treatment between May 2005 and February 2009. Endovascular treatment was defined as pharmacological and/or mechanical intervention, angioplasty, stenting, or a combination of these methods. Admission National Institutes of Health Stroke Scale and the modified Rankin Scale scores were recorded. Thrombolysis in Myocardial Infarction (TIMI) scores of 0, 1, 2A, 2B, and 3 were used to define recanalization. RESULTS: Forty procedures were performed in 39 patients, with 1 patient having sequential bilateral strokes. Nine patients were lost to follow-up after discharge. Strokes in the carotid artery circulation occurred in 82.5% of cases, and those in the vertebral-basilar territory occurred in 17.5%. The Merci device was used in 22 (55%) of 40 procedures, and the Penumbra device in 9 (22.5%) of 40. Angioplasty was performed in 15 (37.5%) of 40 procedures, and intraarterial recombinant tissue plasminogen activator was administered in 23 (57.5%) of 40 procedures. In 23 (57.5%) of 40 cases, multiple recanalization methods were used. The recanalization rate for all methods was 60%. The recanalization rate from TIMI Score 0/1 occlusions was 71.4% (20 of 28). An estimated modified Rankin Scale score of ≤ 2 was obtained in 11 (36.7%) of 30 cases. The overall mortality rate was 26.7% (8 of 30). Intracerebral hemorrhage at 24 hours postprocedure was noted in 17 (42.5%) of 40 cases, 3 (7.5%) of which were symptomatic. CONCLUSIONS: The authors' institution performs endovascular stroke treatment with a safety and efficacy profile comparable to those of other major endovascular stroke therapy studies. Recanalization was associated with an improved clinical outcome. Protocols to maximize efficient triage of patients and better documentation of stroke treatments can assist in further studies.

Normalization of Peri-Arteriovenous Malformation Hemodynamics Prior to Direct Microsurgery: 2-Dimensional Operative Video.

Arteriovenous malformations (AVMs) are highly complex vascular lesions characterized by abnormal connections between arteries and an intervening nidus. Definitive and safe treatment of AVMs may require the combination of multiple treatment modalities to address the various complex features of the AVM.1 Endovascular embolization can be used as an adjuvant to surgery in order to control deep feeders, reduce flow, and address high-risk features such as aneurysms. In addition, by progressively reducing the AVM flow, staged embolization can lead to normalization of peri-AVM hemodynamics and therefore may decrease the risk of postresection hemorrhage.2,3 In this operative video, we present a case of a 41-yr-old female who presented with progressively worsening left-sided hemiparesis. Magnetic resonance imaging (MRI) and angiography revealed a complex right fronto-parietal AVM with significant associated edema, likely due to the vascular steal phenomenon. The area of edema, which included the motor cortex, was thought to be at high risk for postoperative hemorrhage from normal perfusion pressure breakthrough. We therefore decided to proceed with staged presurgical embolization to gradually normalize the perilesional hemodynamics, and therefore possibly reduce the risk of postoperative morbidity. The patient underwent 3 embolization sessions at 6-wk intervals. An MRI after the last embolization showed near-complete resolution of the fluid-attenuated inversion-recovery (FLAIR) signal around the AVM. Microsurgical resection was performed on the day after the last embolization. The patient tolerated the procedure well and was discharged at her neurological baseline with mild contralateral hemiparesis, which has continued to improve at follow-up. Postoperative angiography showed complete resection of the AVM. The patient consented to the procedure as shown in this operative video and gave informed written consent for use of her images in publication.

Quality of Life of Patients with Unruptured Intracranial Aneurysms Before and After Endovascular Coiling: A HEAT Trial Secondary Study and Systematic Review of the Literature.

BACKGROUND: The study of quality of life (QOL) in patients with asymptomatic diseases receiving interventional treatment provides an essential metric for the assessment of procedural benefits in the surgical patient population. In this study, we analyzed QOL data collected from patients with unruptured intracranial aneurysms (UIAs) before and after endovascular coiling in the HEAT Trial, alongside a systematic review on QOL in unruptured brain aneurysms. METHODS: HEAT was a randomized controlled trial comparing recurrence rates in aneurysms treated with either bare platinum coils or hydrogel coils. Patients enrolled in this trial completed a short form-36 (SF-36) QOL questionnaire before treatment and at the 3- to 12- and 18- to 24-month follow-ups. The change in QOL before and after treatment was assessed. Regression analysis evaluated the effect of select baseline characteristics on QOL change. RESULTS: A total of 270 patients were eligible for analysis. There was an increase in the role physical (P = 0.043), vitality (P = 0.022), and emotional well-being (P < 0.001) QOL components at the 18- to 24-month follow-up compared with baseline scores. Regression analysis showed that age younger than 60 and absence of serious adverse events were associated with improved social functioning and vitality. The literature review showed a mixed effect of intervention on QOL in patients with UIAs. CONCLUSIONS: Our analysis has revealed that patients with 3- to 14-mm UIAs had improvements in some physical and emotional components of QOL at 18-24 months following aneurysm coiling in the HEAT study. The literature remains indeterminate on this issue. Further studies are needed to better understand the effects of the diagnosis of UIAs and their treatment on QOL.

The Utility of 5-Aminolevulinic Acid for Microsurgical Resection of Meningiomas.

Fluorescence-guided resection of brain tumors using 5-aminolevulinic acid (5-ALA) has been established for high-grade gliomas. Recently, its application for the resection of low grade tumors and benign lesions including meningioma has been suggested in the literature.1 Achieving a Simpson grade I resection in meningioma surgery is associated with a lower rate of recurrence.2,3 Although meningiomas are mostly benign and well-circumscribed lesions, they can be locally aggressive, invading brain parenchyma and other critical structures. In these cases, 5-ALA-guided resection may help maximize the extent of tumor resection and limit disruption of normal structures. In this video, we present 3 cases demonstrating the use of 5-ALA-induced fluorescence to alleviate 3 specific challenges in meningioma resection: 1) to aid visualization with a minimally invasive approach, 2) to distinguish recurrent tumor from scar tissue from prior treatments, and 3) to ensure that no viable tumor cells remain on the surface of a critical artery. The first patient is a 60-year-old woman who was found to have an incidental left sphenoid wing meningioma on magnetic resonance imaging. We elected for an extended lateral orbital craniotomy through a transpalpebral approach. The second patient is a 72-year-old man with recurrent left occipital parietal meningioma who underwent a parietal craniotomy. The third case was a 62-year-old woman with a foramen magnum meningioma encircling the left vertebral artery. These cases demonstrate the utility of 5-ALA in a variety of challenges associated with resection of meningiomas (Video 1).

Endovascular Embolization of a Lateral Sacral Fistula: 2-Dimensional Operative Video.

Spinal dural arteriovenous fistulas are the most common vascular malformations of the spine. They are localized in the sacral spine in 5% to 14% of the cases. They can be fed by the median or the lateral sacral arteries. These lesions present with nonspecific symptoms such as radiculopathy and/or myelopathy, which often leads to a delay in diagnosis. In this video, we present the case of a 65-yr-old gentleman with a lateral sacral dural arteriovenous fistula. The patient was referred to our institution after the outside facility workup was nondiagnostic. He presented with spastic paraparesis and bilateral radiculopathy. After patient informed consent was obtained, we performed a spinal diagnostic angiogram with catheterization and angiography of the internal iliac artery, which revealed the fistula. Onyx (Medtronic, Dublin, Ireland) embolization was performed, which led to a complete occlusion of the fistula. The patient had complete neurological recovery, and at 2-yr follow-up, imaging remained negative for a fistula. In this video, we discuss the nuances and key points related to the epidemiology, diagnosis, and treatment of lateral sacral fistulas.1-3.

Utility of Augmented Reality Imaging (GLOW800) in Resection of Hemangioblastoma.

This is a surgical video that sheds light on the utility of a new imaging modality GLOW800 (Leica Microsystems, Wetzlar, Germany) in resection of vascular tumors. We describe the surgical resection of posterior fossa hemangioblastoma in 2 different patients after informed consent was obtained. In the first case no intraoperative angiographic imaging was used, while in the second case GLOW800 was used. Because of its ability to overlay the augmented reality view on the surgical field, it allowed for localization of highly vascular tumors as seen in the second patient. In addition, it helped in the confirmation of complete resection of the lesion. Another advantage of GLOW800 was that it allowed safe resection of the lesion in and around highly eloquent areas with a narrow surgical corridor (Video 1).

Surgical Outcomes with Midline versus Lateral Approaches for Cranial Base Chordomas: A Systematic Review and Meta-Analysis.

BACKGROUND: Cranial base chordomas are complex lesions centered on the clivus that surgically can be approached from either a midline or a lateral corridor. OBJECTIVE: To compare the surgical outcomes from midline versus lateral approaches by conducting a meta-analysis of the literature. METHODS: Studies were identified between 2000 and 2018. The primary outcome was gross total resection (GTR) rate. The secondary outcomes were recurrence rate and rates of cerebrospinal fluid (CSF) leak and new cranial nerve palsy. Odds ratios were calculated with a random-effect model using studies describing both approaches. An indirect (proportion) meta-analysis was performed pooling studies describing either of the approaches. Individual patient data were analyzed for differences in GTR or recurrence rate with different tumor extensions. RESULTS: Thirty-three studies were found suitable for indirect meta-analysis and 10 studies for direct meta-analysis. The overall odds of GTR with a midline approach compared with a lateral approach was 0.83 (95% confidence interval [CI], -0.43 to 1.62). The odds ratios for recurrence, CSF leak, and new cranial nerve palsy were 0.82 (95% CI, 0.26-2.56), 1.49 (95% CI, 0.14-15.5), and 0.14 (95% CI, 0.04-0.56), respectively. With individual patient data analysis, no statistically significant difference was observed in GTR or recurrence rates between the 2 approaches with different tumor extensions. CONCLUSIONS: The meta-analysis did not show any significant difference in GTR or recurrence rates between the midline versus lateral approaches. Tumor extension to different compartments did not affect the GTR or recurrence rates with either approach. In terms of complications, CSF leak rate was higher in midline approaches and cranial nerve palsy was higher in lateral approaches.

The Hydrogel Endovascular Aneurysm Treatment Trial (HEAT): A Randomized Controlled Trial of the Second-Generation Hydrogel Coil.

BACKGROUND: Aneurysm recurrence after coiling has been associated with aneurysm growth, (re)hemorrhage, and a greater need for follow-up. The second-generation HydroCoil Embolic System (HES; MicroVention, Inc) consists of a platinum core with integrated hydrogel and was developed to reduce recurrence through enhancing packing density and healing within the aneurysm. OBJECTIVE: To compare recurrence between the second-generation HES and bare platinum coil (BPC) in the new-generation Hydrogel Endovascular Aneurysm Treatment Trial (HEAT). METHODS: HEAT is a randomized, controlled trial that enrolled subjects with ruptured or unruptured 3- to 14-mm intracranial aneurysms amenable to coiling. The primary endpoint was aneurysm recurrence using the Raymond-Roy scale. Secondary endpoints included minor and major recurrence, packing density, adverse events related to the procedure and/or device, mortality, initial complete occlusion, aneurysm retreatment, hemorrhage from target aneurysm during follow-up, aneurysm occlusion stability, and clinical outcome at final follow-up. RESULTS: A total of 600 patients were randomized (HES, n = 297 and BPC, n = 303), including 28% with ruptured aneurysms. Recurrence occurred in 11 (4.4%) subjects in the HES arm and 44 (15.4%) subjects in the BPC arm (P = .002). While the initial occlusion rate was higher with BPC, the packing density and both major and minor recurrence rates were in favor of HES. Secondary endpoints including adverse events, retreatment, hemorrhage, mortality, and clinical outcome did not differ between arms. CONCLUSION: Coiling of small-to-medium aneurysms with second-generation HES resulted in less recurrence when compared to BPC, without increased harm. These data further support the use of the second-generation HES for the embolization of intracranial aneurysms.