Management of failed flow diversion for intracranial aneurysm beyond the first 6 months of follow-up: an international Delphi consensus.

OBJECTIVE: The placement of flow-diverting devices has become a common method of treating unruptured intracranial aneurysms of the internal carotid artery. The progressive improvement of aneurysm occlusion after treatment-with low complication and rupture rates-has led to a dilemma regarding the management of aneurysms in which occlusion has not occurred within 6-24 months. The authors aimed to identify clinical consensus regarding management of intracranial aneurysms displaying persistent filling 6-24 months after flow diversion and to ascertain questions that may drive future investigation. METHODS: An international panel of 67 experts was invited to participate in a multistep Delphi consensus process on the treatment of intracranial aneurysms after failed flow diversion. RESULTS: Of the 67 experts invited, 23 (34%) participated. Qualitative analysis of an initial survey with open-ended questions resulted in 51 statements regarding management of aneurysms showing persistent filling after flow diversion. The statements were grouped into 8 categories, and in the second round, respondents rated the degree of their agreement with each statement on a 5-point Likert scale. Flow diverters with surface modifiers did not influence administration of dual-antiplatelet therapy according to 83%. Consensus was also reached regarding the definition of treatment failure at specific time points, including at 6 months if there is aneurysm growth or persistent rapid flow through the entirety of the aneurysm (96%), at 12 months if there is aneurysm growth or symptom onset (78%), and at 24 months if there is persistent filling regardless of size and filling characteristics (74%). Although experts agreed that the degree of intimal hyperplasia or in-device stenosis could not be ascertained by noninvasive imaging alone (83%), only 65% chose digital subtraction angiography as the preferred modality. At 6 and 12 months, retreatment is preferred if there is persistent filling with aneurysm growth (96%, 96%), device malposition (48%, 87%), or a history of subarachnoid hemorrhage (65%, 70%), respectively, and at 24 months if there is persistent filling without reduction in aneurysm size (74%). Experts favored treatment with an additional flow diverter (87%) over aneurysm clipping, applying the same principles for follow-up (83%) and treatment failure (91%) as for the first flow diverter. CONCLUSIONS: The authors present the consensus practices of experts in the management of intracranial aneurysms without occlusion 6-24 months after treatment with a flow-diverting device.

Risk factors associated with in-hospital complications for pediatric sickle-cell disease-associated moyamoya syndrome: a nationwide cross-sectional study.

PURPOSE: Sickle-cell disease-associated moyamoya syndrome (SCD-MMS) carries a high risk for recurrent strokes and cerebrovascular morbidity in children. However, few data are available about complications that occur in children hospitalized with SCD-MMS. The purpose of this analysis was to determine the risk factors for in-hospital complications in pediatric SCD-MMS admissions, and thus aid physicians in optimizing future treatment plans. METHODS: A national database of pediatric hospital admissions was examined across the years 2003-2019. ICD-9 and ICD-10 diagnosis codes were analyzed to identify discharges with a primary diagnosis of SCD-MMS and identify in-hospital complications, defined as complication-associated diagnostic codes logged during the same admission. Patient demographics, comorbidities, and hospital characteristics were examined using univariate and multivariate logistic regression analyses to determine associations with in-hospital complications. RESULTS: In total, 274 admissions with a primary diagnosis of SCD-MMS were identified. During 64 (23.4%) admissions, transfusion therapy was given, and in 86 admissions (31.4%), surgical revascularization was performed. In 10 admissions (3.6%), a total of 11 in-hospital complications were identified. After multivariate regression, both comorbid chronic lung disease (adjusted OR 5.3 [1.1, 26.9], P = 0.04) and surgical revascularization (adjusted OR 10.2 [2.0, 52.4], P = 0.006) were associated with development of complications. CONCLUSIONS: In this nationwide database of pediatric SCD-MMS hospitalizations, comorbid chronic lung disease and surgical revascularization were associated with development of in-hospital complications. Patients with comorbid chronic lung disease or who are admitted for revascularization may warrant closer monitoring and greater medical optimization during the hospitalization.

The VEBAS score: a practical scoring system for intracranial dural arteriovenous fistula obliteration.

BACKGROUND: Tools predicting intracranial dural arteriovenous fistulas (dAVFs) treatment outcomes remain scarce. This study aimed to use a multicenter database comprising more than 1000 dAVFs to develop a practical scoring system that predicts treatment outcomes. METHODS: Patients with angiographically confirmed dAVFs who underwent treatment within the Consortium for Dural Arteriovenous Fistula Outcomes Research-participating institutions were retrospectively reviewed. A subset comprising 80% of patients was randomly selected as training dataset, and the remaining 20% was used for validation. Univariable predictors of complete dAVF obliteration were entered into a stepwise multivariable regression model. The components of the proposed score (VEBAS) were weighted based on their ORs. Model performance was assessed using receiver operating curves (ROC) and areas under the ROC. RESULTS: A total of 880 dAVF patients were included. Venous stenosis (presence vs absence), elderly age (<75 vs ≥75 years), Borden classification (I vs II-III), arterial feeders (single vs multiple), and past cranial surgery (presence vs absence) were independent predictors of obliteration and used to derive the VEBAS score. A significant increase in the likelihood of complete obliteration (OR=1.37 (1.27-1.48)) with each additional point in the overall patient score (range 0-12) was demonstrated. Within the validation dataset, the predicted probability of complete dAVF obliteration increased from 0% with a 0-3 score to 72-89% for patients scoring ≥8. CONCLUSION: The VEBAS score is a practical grading system that can guide patient counseling when considering dAVF intervention by predicting the likelihood of treatment success, with higher scores portending a greater likelihood of complete obliteration.

Patient-reported outcome measures in cerebrovascular neurosurgery.

OBJECTIVE: The object of this study was to describe the use of patient-reported outcome measures (PROMs) in cerebrovascular neurosurgery and to outline a framework for incorporating them into future cerebrovascular research. METHODS: Following the standardized PRISMA guidelines, the authors performed a search of the PubMed and Embase databases in February 2023 using filters to investigate six specific cerebrovascular pathologies/procedures: subarachnoid hemorrhage (SAH), intracranial hemorrhage, ischemic stroke, arteriovenous malformation, chronic subdural hematoma, and carotid artery stenosis. PROMs in the identified articles were distinguished and classified as generic, symptom specific, or disease specific. RESULTS: A total of 259 studies including 51 PROMs were eligible for inclusion in the review. Most of the PROMs were generic or symptom specific. Only 5 PROMs were disease specific, and all of these pertained to stroke or SAH. CONCLUSIONS: There are only a limited number of disease-specific PROMs available for cerebrovascular pathologies and outcomes. Further validation of existing measures in independent cohorts, expanded incorporation of disease-specific PROMs in prospective trials, and the development of new PROMs specific to cerebrovascular conditions are critical to a better understanding of the impact of cerebrovascular diseases and novel therapies on patient lives.

Trapping and side-to-end superior cerebellar artery to superior cerebellar artery bypass for treatment of fusiform superior cerebellar artery aneurysm.

We describe the technical nuances of in-situ bypass for treatment of a fusiform superior cerebellar artery (SCA) aneurysm via surgical trapping and a side-to-end in-situ bypass between duplicated SCAs. Our patient is a 40-year-old male who presented with an incidental aneurysm of the proximal right superior cerebellar artery (SCA). Formal angiography was performed that demonstrated a fusiform morphology of the aneurysm, as well as a duplicated SCA on that side. After extensive counseling, the patient elected to undergo surgical clip reconstruction with possible bypass. A large frontotemporal craniotomy was performed and a combined transsylvian-subtemporal approach to the ventral anterolateral brainstem was performed. After identifying the aneurysm, the tentorium was incised posterior to the insertion of the trochlear nerve to widen the operative field. An end-to-side anastomosis between the duplicated SCAs was performed, followed by trapping of the diseased arterial segment. The patient had an oculomotor nerve palsy post-operatively, however this resolved by his six-month follow-up. In-situ bypass is a viable technique for revascularizing the SCA territory during clip reconstruction of fusiform aneurysms. A duplicated SCA allows for an SCA to SCA bypass. Incising the tentorium can increase visualization of donor and recipient vessels and facilitate performance of the anastomosis.

Use of Proximal Suboccipital Segment of Occipital Artery as Donor for Posterior Circulation Revascularization Surgery: Technical Note.

BACKGROUND: The distal suboccipital segment of the occipital artery is commonly used as a donor vessel for aneurysms of the posterior circulation requiring revascularization techniques. Isolating this segment of vessel can be challenging due to its course in and out of the various layers of the suboccipital musculature. METHODS: We describe the use of the proximal suboccipital segment of the occipital artery within the occipital groove at the lateral skull base as a donor segment for an interposition graft in revascularization surgery. We present a case detailing the use of this technique for treatment of a dissecting PICA aneurysm and photographs from cadaveric dissections demonstrating relevant anatomy. RESULTS: Our patient is a 62-year-old man who presented with a high-grade subarachnoid hemorrhage from a proximal dissecting-type aneurysm of the posterior inferior cerebellar artery (PICA). Endovascular options were limited to coil sacrifice of the parent vessel, and thus the patient was taken for a far lateral craniotomy, trapping of the aneurysm, and revascularization of the PICA territory via a saphenous vein interposition graft sewn proximally and distally to the occipital artery within the occipital groove and a cortical segment of the affected PICA, respectively. Postoperative imaging demonstrated filling of the PICA territory via the graft, and the patient ultimately recovered from his subarachnoid hemorrhage. CONCLUSIONS: The use of the proximal suboccipital segment of the occipital artery is a viable option for a donor in posterior fossa revascularization surgery.

Transpeduncular Approach for Resection of Ruptured Fourth Ventricular Arteriovenous Malformation.

The lateral recess of the fourth ventricle can be challenging to access surgically. We present a case of a previously ruptured arteriovenous malformation (AVM) of the fourth ventricle that was surgically resected via a retrosigmoid craniotomy and transinferior cerebellar peduncular approach. The patient is a 54-year-old female who experienced an intraventricular hemorrhage several months before presentation to our institution. Imaging studies suggested the presence of an AVM located in the right lateral recess of the fourth ventricle. After discussion of all possible treatment options, the patient elected to proceed with surgical resection. To access the lesion, we performed a retrosigmoid craniotomy and entered into the fourth ventricle via s small incision in the inferior cerebellar peduncle. Postoperative imaging demonstrated complete removal of the AVM nidus. Video 1 demonstrates this approach and discusses the anatomic landmarks used to guide resection.

Factors Associated with Unfavorable Clinical Presentations in Patients with Ruptured BrainArteriovenous Malformations.

BACKGROUND: Rupture of brain arteriovenous malformations (bAVMs) carries potentially devastating consequences. For patients presenting with ruptured bAVMs, several clinical grading systems have been shown to predict long-term patient morbidity and may be taken into consideration when making clinical decisions. Unfortunately, use of these scoring systems is typically limited to their prognostic value and offer little to patients in therapeutic benefit. Tools are needed not only to predict prognosis for patients experiencing ruptured bAVMs but to gain insight into what characteristics predispose patients to poor long-term outcomes before they rupture. Our objective was to find clinical, morphologic, and demographic variables that correlate with unfavorable clinical grades on presentation in patients with ruptured bAVMs. METHODS: We retrospectively reviewed a cohort of patients with ruptured bAVMs. Linear regression models were used to test whether Glasgow Coma Scale (GCS) and Hunt-Hess scores on presentation(outcomes) were associated with patient and arteriovenous malformation (AVM) characteristics (predictors) individually. RESULTS: GCS and Hunt-Hess were assessed following bAVM rupture for 121 brain cases. The median age at rupture was 28.5 years, and 62 (51%) were female. Smoking history was associated with worse GCS; current and past smokers had GCS scores 1.33 points lower on average than nonsmokers (95% confidence interval [CI] -2.59 to -0.07, P = 0.039) and had worse Hunt-Hess scores (0.42, 95% CI 0.07-0.77, P = 0.019). Associated aneurysms were associated with worse GCS (-1.60, 95% CI -3.16 to -0.05, P = 0.043) and trended towards worse Hunt-Hess scores (0.42 points, 95% CI -0.01 to 0.86, P = 0.057). CONCLUSIONS: Patient smoking status and presence of an AVM associated aneurysm were shown to have modest correlations with unfavorable clinical grades (Hunt-Hess, GCS) on presentation, with unfavorable clinical grades being associated with long-term patient prognosis following bAVM rupture. Further investigation using AVM-specific grading scales and external data are needed to determine the utility of these and other variables in clinical practice for patients with bAVM.

Endonasal Endoscopic Anatomy of the Orbito-Cavernous-Pterygopalatine Interface: Multilayer Anatomical Description and Landmarks to Define the Limits of the Compartments.

BACKGROUND: Despite growing interest in the endoscopic endonasal approach (EEA) to the medial orbital apex (OA), a comprehensive description of the multilayer topology lying at the intersection of the regional compartments is missing. METHODS: An EEA to the OA, pterygopalatine fossa, and cavernous sinus was performed in 20 specimens. A 360° layer-by-layer dissection was performed taking into consideration relevant anatomical aspects of the interface and documented with 3-dimensional technologies. Endoscopic landmarks were analyzed to provide an outline of the compartments and identify critical structures. Additionally, the consistency of a previously described reference called orbital apex convergence prominence was analyzed and a method to identify its position was introduced. RESULTS: The orbital apex convergence prominence was an inconsistent finding (15%). However, a craniometric method introduced in this study proved to be reliable to reach the orbital apex convergence point. Additional structures such as the sphenoethmoidal suture and a 3-suture junction (sphenoethmoidal-palatoethmoidal-palatosphenoidal) helped to identify the posterior limit of the OA and define a keyhole to access the compartments of the interface. We defined the bone limits of the "optic risk zone," an area where the optic nerve is more susceptible to damage. Furthermore, an orbital fusion line (periorbita-dura-periosteum) was identified and divided into 4 segments according to adjacent structures: optic, cavernous, pterygopalatine, and infraorbital. CONCLUSIONS: Understanding cranial landmarks and the folds of the layers covering the orbito-cavernous-pterygopalatine interface can facilitate tailoring an EEA to the medial orbital space and avoid unnecessary exposure of sensitive anatomy in the vicinity.

Common Carotid-Greater Saphenous-M2 Bypass for Myoepithelial Carcinoma Encasing the Carotid Artery.

Revascularization of the anterior circulation using a high-capacitance graft is sometimes necessary for treatment of cervical tumors encasing the internal carotid artery (ICA). In this surgical video, we aim to demonstrate the technical nuances of high-flow extra-to-intracranial bypass using a saphenous vein graft. The patient is a 23-year-old female who presented with a 4-month history of an enlarging left-sided neck mass, dysphagia, and 25-lb weight loss. Computed tomography and magnetic resonance imaging demonstrated an enhancing lesion encasing the cervical ICA. The patient underwent an open biopsy that established a diagnosis of a myoepithelial carcinoma. The patient was advised to undergo attempted gross total resection, which would require sacrifice of the cervical internal carotid artery. After the patient failed a balloon test occlusion of the left ICA, it was decided to perform a cervical ICA to middle cerebral artery M2 bypass using a saphenous vein graft, followed by tumor resection in staged fashion. Postoperative imaging demonstrated complete tumor removal and filling of the left anterior circulation via the saphenous vein graft. Video 1 discusses important preoperative and postoperative considerations, as well as highlights the technical nuances of this complex procedure. High-flow ICA to middle cerebral artery bypass using a saphenous vein graft can be employed to facilitate gross total resection of malignant tumors encasing the cervical internal carotid artery.

Morphometric Analysis of the Ophthalmic and Central Retinal Arteries via the Endoscopic Endonasal Trans-ethmoidal Approach: Surgical Relevance of Vascular Components Within the Medial Intraconal Zones.

BACKGROUND: The endoscopic endonasal approach (EEA) offers a minimally invasive route to treat medial intraconal space (MIS) lesions. Understanding the configuration of the ophthalmic artery (OphA) and the central retinal artery (CRA) is crucial. METHODS: An EEA to the MIS was performed on 30 orbits. The description of the intraorbital part of the OphA was divided into 3 segments and classified as type 1 and type 2 and the MIS was divided into three surgical zones (A, B, C). The CRA's origin, course, and point of penetration (PP) were analyzed. The relationship between the position of the CRA in the MIS and the OphA type was analyzed. RESULTS: The OphA type 2 was present in 20% of specimens. The site of origin of the CRA from the OphA was found on the medial surface in type 1 and on the lateral surface of type 2. The point of penetrationof the central retinal arterywas found in 87% of the specimens on the inferomedial surface, just anterior to the inferior muscular trunk, at an average distance of 9.5 mm ± 1 from the globe and 17 mm ± 1.5 from the AZ. The presence of the CRA in Zone C was associated only with OphA type 1. CONCLUSIONS: OphA type 2 is a common finding and can compromise the feasibility of an EEA to the MIS. A detailed preoperative analysis of the OphA and CRA should be conducted prior to approaching the MIS due to the implications of the anatomical variations that can compromise safe intraconal maneuverability during an EEA.

Clarifying the clinical landscape of pediatric spinal arteriovenous shunts: an institutional experience and individual patient-data meta-analysis.

BACKGROUND: Pediatric spinal arteriovenous shunts (SAVS) are rare lesions with heterogeneous pathogenesis and clinical manifestations. OBJECTIVE: To evaluate the clinical characteristics, angioarchitecture, and technical/clinical outcomes in SAVS through a large single-center cohort analysis and meta-analysis of individual patient data. METHODS: A retrospective institutional database identified children (aged 0-21 years) who underwent digital subtraction spinal angiography (DSA) for SAVS between January 1996 and July 2021. Clinical data were recorded to evaluate angioarchitecture, generate modified Aminoff-Logue gait disturbance scores (AL) and McCormick grades (MC), and assess outcomes. We then performed a systematic literature review following PRISMA-IPD (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for individual patient data) guidelines, extracting similar data on individual patients for meta-analysis. RESULTS: The cohort consisted of 28 children (M:F=11:17) with 32 SAVS lesions, with a mean age of 12.8±1.1 years at diagnosis. At presentation, SAVS were most highly concentrated in the cervical region (40.6%). Children had a median AL=2 and MC=2, with thoracolumbar AVS carrying the greatest disability. Among treated cases, complete obliteration was achieved in 48% of cases and median AL scores and MC grades both improved by one point. Systematic literature review identified 161 children (M:F=96:65) with 166 SAVS lesions with a mean age of 8.7±0.4 years. Among studies describing symptom chronicity, 37/51 (72.5%) of children presented acutely. At presentation, children had a median AL=4 and MC=3, with thoracolumbar AVS carrying the highest MC grades. After intervention, median AL and MC both improved by one point. CONCLUSIONS: This study provides epidemiologic information on the location, onset, and presentation of the full spectrum of pediatric SAVS, highlighting the role of targeted treatment of high-risk features.

A comparison of incidental and symptomatic unruptured brain arteriovenous malformations in children.

OBJECTIVE: Patients with unruptured brain arteriovenous malformations (AVMs) may present with headaches, seizures, and/or neurological deficits. A smaller number of cases may be discovered incidentally. These lesions remain incompletely understood due to their sparse reporting. Herein, the authors describe the largest series to date comparing the presentation, angioarchitecture, and management of incidental versus symptomatic unruptured AVMs in children. METHODS: The authors performed a retrospective analysis of patients who presented with brain AVMs from 1998 to 2022 at the University of California, San Francisco. Inclusion criteria were age ≤ 18 years at the time of presentation and an angiographically proven unruptured AVM that had been diagnosed postnatally. RESULTS: Of 76 children with unruptured AVMs, 66 (86.8%) presented with headaches, seizures, and/or neurological deficit. Ten AVMs (13.1%) were incidentally discovered through unrelated disease workup (50%), cranial trauma (40%), or research study participation (10%). Compared with patients with symptomatic unruptured AVMs, patients with incidental unruptured AVMs had a smaller mean ± SD maximum nidus diameter (2.82 ± 1.1 vs 3.98 ± 1.52 cm, p = 0.025) and fewer had deep venous drainage (20% of patients vs 61%, p = 0.036). They also presented at an earlier age (10 ± 5.2 vs 13.5 ± 4 years, p = 0.043) and with longer duration to first treatment (541 ± 922 vs 196 ± 448 days, p = 0.005). During the observation period, 1 patient developed recurring headaches and demonstrated AVM nidus growth. Four AVMs greater than 3 cm in size or in a deep location were treated with radiosurgery. Six other AVMs were treated with resection, with 2 receiving preoperative embolization. Eight AVMs (80%) were obliterated on last follow-up. Postprocedural complications included 2 transient neurological deficits after resection and 1 case of delayed seizure development after radiosurgery. The mean follow-up period was 5.7 ± 5.7 years without any hemorrhage episodes. CONCLUSIONS: A substantial proportion of pediatric patients with unruptured AVMs are discovered incidentally. With earlier presentation and more elementary angioarchitecture than symptomatic unruptured AVMs, these incidental lesions provide a snapshot into the natural history of AVM before symptom development or rupture.

Intracranial Hemorrhage Rate and Lesion Burden in Patients With Familial Cerebral Cavernous Malformation.

Background Familial cerebral cavernous alformation (CCM) is an autosomal dominant disease caused by mutations in KRIT1, CCM2, or PDCD10. Cases typically present with multiple lesions, strong family history, and neurological symptoms, including seizures, headaches, or other deficits. Intracranial hemorrhage (ICH) is a severe manifestation of CCM, which can lead to death or long-term neurological deficits. Few studies have reported ICH rates and risk factors in familial CCM. We report ICH rates and assess whether CCM lesion burden, a disease severity marker, is associated with risk of symptomatic ICH during follow-up in a well-characterized cohort of familial CCM cases. Methods and Results We studied 386 patients with familial CCM with follow-up data enrolled in the Brain Vascular Malformation Consortium CCM Project. We estimated symptomatic ICH rates overall and stratified by history of ICH before enrollment. CCM lesion burden (total lesion count and large lesion size) assessed at baseline enrollment was tested for association with increased risk of subsequent ICH during follow-up using Cox regression models adjusted for history of ICH before enrollment, age, sex, and family structure and stratified on recruitment site. The symptomatic ICH rate for familial CCM cases was 2.8 per 100 patient-years (95% CI, 1.9-4.1). Those with ICH before enrollment had a follow-up ICH rate of 4.5 per 100 patient-years (95% CI, 2.6-8.1) compared with 2.0 per 100 patient-years (95% CI, 1.3-3.5) in those without (P=0.042). Total lesion count was associated with increased risk of ICH during follow-up (hazard ratio [HR], 1.37 per doubling of total lesion count [95% CI, 1.10-1.71], P=0.006). The symptomatic ICH rate for familial CCM cases was 2.8 per 100 patient-years (95% CI, 1.9-4.1). Those with ICH before enrollment had a follow-up ICH rate of 4.5 per 100 patient-years (95% CI, 2.6-8.1) compared with 2.0 per 100 patient-years (95% CI, 1.3-3.5) in those without (P=0.042). Total lesion count was associated with increased risk of ICH during follow-up (hazard ratio [HR], 1.37 per doubling of total lesion count [95% CI, 1.10-1.71], P=0.006). Conclusions Patients with familial CCM with prior history of an ICH event are at higher risk for rehemorrhage during follow-up. In addition, total CCM lesion burden is significantly associated with increased risk of subsequent symptomatic ICH; hence lesion burden may be an important predictor of patient outcome and aid patient risk stratification.