Proton versus photon adjuvant radiotherapy: a multicenter comparative evaluation of recurrence following spinal chordoma resection.

OBJECTIVE: Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models. METHODS: The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS: Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01-0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%-99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%). CONCLUSIONS: Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.

Treatment of recurrent and persistent Cushing's disease after first transsphenoidal surgery: lessons learned from an international meta-analysis.

PURPOSE: Transsphenoidal surgery (TSS) is the first-line treatment for patients with Cushing's Disease (CD). Recurrence rates after a first TSS range between 3 and 22% within 3 years. Management of recurrent or persistent CD may include repeat TSS or stereotactic radiosurgery (SRS). We performed a meta-analysis to explore the overall efficacy of TSS and SRS for patients with CD after an initial surgical intervention. METHODS: EMBASE, PubMed, SCOPUS, and Cochrane databases were searched from their dates-of-inception up to December 2021. Inclusion criteria were comprised of patients with an established diagnosis of CD who presented with persistent or biochemically recurrent disease after a first TSS for tumor resection and were treated with a second TSS or SRS. RESULTS: Search criteria yielded 2,116 studies of which 37 articles from 15 countries were included for analysis. Mean age ranged between 29.9 and 47.9 years, and mean follow-up was 11-104 months. TSS was used in 669 (67.7%) patients, while SRS was used in 320 (32.4%) patients, and remission rates for CD were 59% (95%CI 0.49-0.68) and 74% (95%CI 0.54-0.88), respectively. There was no statistically significant difference in the remission rate between TSS and SRS (P = 0.15). The remission rate of patients with recurrent CD undergoing TSS was 53% (95%CI 0.32-0.73), and for persistent CD was 41% (95%CI 0.28-0.56) (P = 0.36). CONCLUSION: Both TSS and SRS are possible approaches for the treatment of recurrent or persistent CD after a first TSS. Our data show that either TSS or SRS represent viable treatment options to achieve remission for this subset of patients.

Repeat Catheter Angiography in Patients with Aneurysmal-Pattern Angiographically Negative Subarachnoid Hemorrhage.

BACKGROUND: A significant proportion of patients with subarachnoid hemorrhage have a normal cerebral angiogram. Patients with angiographically negative subarachnoid hemorrhage (anSAH) with either perimesencephalic- (panSAH) or aneurysmal-pattern hemorrhage (aanSAH, also known as diffuse anSAH) have an excellent prognosis, but only if underlying vascular abnormalities are completely excluded. The rate of occult aneurysms in patients with aanSAH varies widely across studies. The purpose of this study was to quantify the value of repeat DSA in these patients. METHODS: We reviewed the records of all patients initially diagnosed with aanSAH after a screening DSA at a single tertiary neurovascular referral center from January 2006-April 2018. Patients with panSAH and traumatic SAH were excluded. We also performed a systematic review and meta-analysis of positive second DSAs in previously published case series of patients with aanSAH who underwent two serial DSAs. For meta-analysis, PubMed Central, MEDLINE and Cochrane Library databases were searched for pertinent studies up to November 2019. The rate of aneurysm detection on repeat angiography was extracted from each study. Pooled rates for positive second angiogram were calculated as untransformed proportions in a binary random-effects model meta-analysis. Inter-study heterogeneity was calculated using an I2 statistic. RESULTS: Three of 27 patients (11.1%) with aanSAH and at least two DSAs were subsequently found to have a cerebral aneurysm in our institutional dataset. Twenty-six studies in our systematic review met inclusion criteria, and the pooled rate of positive second angiogram was 10.4% (95% CI 7.3%-13.5%, P < 0.001). Substantial inter-study heterogeneity was observed in the meta-analysis (I2 = 61.7%, P < 0.001). CONCLUSIONS: One in 10 patients with aanSAH has an occult ruptured aneurysm. A second-look DSA should be strongly considered in these cases.

Noncontrast Computed Tomography e-Stroke Infarct Volume Is Similar to RAPID Computed Tomography Perfusion in Estimating Postreperfusion Infarct Volumes.

BACKGROUND AND PURPOSE: The e-Stroke Suite software (Brainomix, Oxford, United Kingdom) is a tool designed for the automated quantification of The Alberta Stroke Program Early CT Score and ischemic core volumes on noncontrast computed tomography (NCCT). We sought to compare the prediction of postreperfusion infarct volumes and the clinical outcomes across NCCT e-Stroke software versus RAPID (IschemaView, Menlo Park, CA) computed tomography perfusion measurements. METHODS: All consecutive patients with anterior circulation large vessel occlusion stroke presenting at a tertiary care center between September 2010 and November 2018 who had available baseline infarct volumes on both NCCT e-Stroke Suite software and RAPID CTP as well as final infarct volume (FIV) measurements and achieved complete reperfusion (modified Thrombolysis in Cerebral Infarction scale 2c-3) post-thrombectomy were included. The associations between estimated baseline ischemic core volumes and FIV as well as 90-day functional outcomes were assessed. RESULTS: Four hundred seventy-nine patients met inclusion criteria. Median age was 64 years (55-75), median e-Stroke and computed tomography perfusion ischemic core volumes were 38.4 (21.8-58) and 5 (0-17.7) mL, respectively, whereas median FIV was 22.2 (9.1-56.2) mL. The correlation between e-Stroke and CTP ischemic core volumes was moderate (R=0.44; P<0.001). Similarly, moderate correlations were observed between e-Stroke software ischemic core and FIV (R=0.52; P<0.001) and CTP core and FIV (R=0.43; P<0.001). Subgroup analysis showed that e-Stroke software and CTP performance was similar in the early and late (>6 hours) treatment windows. Multivariate analysis showed that both e-Stroke software NCCT baseline ischemic core volume (adjusted odds ratio, 0.98 [95% CI, 0.97-0.99]) and RAPID CTP ischemic core volume (adjusted odds ratio, 0.98 [95% CI, 0.97-0.99]) were independently and comparably associated with good outcome (modified Rankin Scale score of 0-2) at 90 days. CONCLUSIONS: NCCT e-Stroke Suite software performed similarly to RAPID CTP in assessing postreperfusion FIV and functional outcomes for both early- and late-presenting patients. NCCT e-Stroke volumes seems to represent a viable alternative in centers where access to advanced imaging is limited. Moreover, the future development of fusion maps of NCCT and CTP ischemic core estimates may improve upon the current performance of these tools as applied in isolation.

Oestrogen-mediated upregulation of the Mas receptor contributes to sex differences in acute lung injury and lung vascular barrier regulation.

Epidemiological data from the SARS-CoV-2 outbreak suggest sex differences in mortality and vulnerability; however, sex-dependent incidence of acute respiratory distress syndrome (ARDS) remains controversial and the sex-dependent mechanisms of endothelial barrier regulation are unknown. In premenopausal women, increased signalling of angiotensin (Ang)(1-7) via the Mas receptor has been linked to lower cardiovascular risk. Since stimulation of the Ang(1-7)/Mas axis protects the endothelial barrier in acute lung injury (ALI), we hypothesised that increased Ang(1-7)/Mas signalling may protect females over males in ALI/ARDS.Clinical data were collected from Charité inpatients (Berlin) and sex differences in ALI were assessed in wild-type (WT) and Mas-receptor deficient (Mas-/- ) mice. Endothelial permeability was assessed as weight change in isolated lungs and as transendothelial electrical resistance (TEER) in vitroIn 734 090 Charité inpatients (2005-2016), ARDS had a higher incidence in men as compared to women. In murine ALI, male WT mice had more lung oedema, protein leaks and histological evidence of injury than female WT mice. Lung weight change in response to platelet-activating factor (PAF) was more pronounced in male WT and female Mas-/- mice than in female WT mice, whereas Mas-receptor expression was higher in female WT lungs. Ovariectomy attenuated protection in female WT mice and reduced Mas-receptor expression. Oestrogen increased Mas-receptor expression and attenuated endothelial leakage in response to thrombin in vitro This effect was alleviated by Mas-receptor blockade.Improved lung endothelial barrier function protects female mice from ALI-induced lung oedema. This effect is partially mediated via enhanced Ang(1-7)/Mas signalling as a result of oestrogen-dependent Mas expression.

Assessment of the American College of Surgeons National Surgical Quality Improvement Program Calculator in Predicting Outcomes and Length of Stay After Ivor Lewis Esophagectomy: A Single-Center Experience.

BACKGROUND: The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) calculator is a useful tool used by physicians to better inform patients on the surgical risk of postoperative complications. It makes use of the NSQIP database to derive the chance for several adverse outcomes to occur postoperatively given certain patient's factors. The aim of this study was to assess its applicability in a series of patients undergoing an Ivor Lewis esophagectomy. METHODS: Data from 100 consecutive patients who underwent an Ivor Lewis esophagectomy between September 2013 and November 2017 at our institution were reviewed. Each patient was assessed using the ACS NSQIP surgical risk calculator. Actual events in this group were compared with their particular NSQIP-assessed risk. Logistic regression models were used to compare surgical risk calculator estimates binary outcomes such as incidence of postoperative complications such as cardiac events, renal events, surgical site infection, and death. Mixed linear model was used for length of stay (LOS) duration versus observed LOS. C-statistic was for predictive accuracy each binary outcome and intraclass correlation was used for LOS. RESULTS: C-statistic values were higher than the cutoff (0.75) for surgical site infection and death. The ACS NSQIP risk calculator was poorly predictive of other reported outcomes by the calculator such as cardiac or renal complications. Corroboration between observed LOS and predicted LOS was weak (8 d versus 11 d, respectively, intraclass coefficient 0.04). CONCLUSIONS: This study suggests that the risk calculator is useful for identifying risk of death or surgical site infection but poor at discriminating likelihood of other reported outcomes occurring, such as pneumonia, acute renal failure and cardiac complications for patients who underwent an Ivor Lewis esophagectomy. Estimations for procedure-specific complications for esophagectomy may need reevaluated.

Recurrence of Rathke's cleft cysts based on gross total resection of cyst wall: a meta-analysis.

Rathke's cleft cysts (RCCs) are benign growths of the embryological Rathke's pouch. Surgical decompression provides effective symptomatic relief in most cases; however, the effect of gross total resection (GTR) of the cyst wall on recurrence, as well as pituitary function, is unclear. The aim of this meta-analysis was to pool the current literature and ascertain the recurrence control afforded by GTR of the cyst wall compared with subtotal resection (STR). Searches of seven electronic databases from inception to January 2019 were conducted following PRISMA guidelines, resulting in 476 articles to be screened. Outcomes were analyzed using meta-analysis of proportions. A total of 10 retrospective cohort studies satisfied selection criteria, describing 655 surgically managed RCC cases, with 254 (39%) and 401 (61%) achieving GTR and STR of the cyst wall, respectively. GTR was associated with significantly reduced overall RCC recurrence by fixed-effects (FE) modeling (RR, 0.66; 95% CI, 0.45-0.96), but not by random effects (RE) modeling (RR, 0.75; 95% CI, 0.51-1.12). Based on both models, GTR was associated with significantly reduced symptomatic recurrence (RE model, RR, 0.37, 95% CI, 0.14-0.95) and significantly increased postoperative diabetes insipidus (RE model, RR, 2.60; 95% CI, 1.34-5.03). There was insufficient data to evaluate other pituitary axes in this context. The current evidence indicates that GTR of the RCC cyst wall has the potential to affect the incidence of overall and symptomatic RCC recurrences, as well as drive postoperative DI incidence. However, expectations of clinical and pragmatic benefit following cyst wall resection should be titrated carefully against the potential for postoperative and pituitary morbidities which currently remain poorly defined. Greater granularity is required to understand all factors that can influence recurrence and quality of life when evaluating resection of RCC.

Efficacy and safety of bevacizumab for vestibular schwannoma in neurofibromatosis type 2: a systematic review and meta-analysis of treatment outcomes.

BACKGROUND: Individual evidence suggests that the anti-angiogenic agent bevacizumab may control vestibular schwannoma (VS) growth and promote hearing preservation in patients with neurofibromatosis type 2 (NF2). However, such metadata has yet to be consolidated, as well as its side-effect profile yet to be fully understood. Our aim was to pool systematically-identified metadata in the literature and substantiate the clinical efficacy and safety of bevacizumab with respect to radiographic tumor response, hearing, and treatment outcomes. METHODS: Searches of seven electronic databases from inception to March 2019 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. The incidence of outcomes was then extracted and pooled by random-effects meta-analysis of proportions. RESULTS: Eight articles reporting 161 NF2 patients with 196 assessable VS met satisfied all criteria. Radiographic response to bevacizumab was partial regression in 41% (95% CI 31-51%), no change in 47% (95% CI 39-55%), and tumor progression in 7% (95% CI 1-15%). In patients with assessable audiometric data, bevacizumab treatment resulted in hearing improvement in 20% (95% CI 9-33%), stability in 69% (95% CI 51-85%) and additional loss in 6% (95% CI 1-15%) Serious bevacizumab toxicity was observed in 17% (95% CI 10-26%). Subsequent surgical intervention was required in 11% (95% CI 2-20%). CONCLUSIONS: Bevacizumab may arrest both tumor progression and hearing loss in select NF2 patients presenting with VS lesions. However, a considerable proportion of patients are anticipated to experience serious adverse events; correspondingly, judicious use of bevacizumab for symptomatic management of VS in NF2 is recommended.

Pediatric neurosurgical bellwether procedures for infrastructure capacity building in hospitals and healthcare systems worldwide.

PURPOSE: Quantifying the global burden of pediatric neurosurgical disease-and current efforts addressing it-is challenging, particularly in the absence of uniform terminology. We sought to establish bellwether procedures for pediatric neurosurgery, in order to standardize terminology, establish priorities, and facilitate goal-oriented capacity building. METHODS: Members of international pediatric neurosurgical and pediatric surgical societies were surveyed via the Research Electronic Data Capture (REDCap) platform. Among 15 proposed neurosurgical procedures, respondents assigned numerical grades of surgical necessity and selected hospital-level designation within a three-tiered system. A procedure was considered a bellwether if (a) the majority of respondents deemed it necessary for either a primary- or secondary-level hospital and (b) the procedure was graded at or above the 90th percentile on a continuous scale of essentiality. Data were compiled and analyzed using Stata software. RESULTS: Complete responses were obtained from 459 surgeons from 76 countries, the majority of whom practiced in a tertiary referral hospital (88%), with a primarily public patient population (64%). Six bellwether procedures were identified for pediatric neurosurgery: shunt for hydrocephalus, myelomeningocele closure, burr holes, trauma craniotomy, external ventricular drain (EVD) insertion, and cerebral abscess evacuation. Few differences in bellwether criteria designations were observed among respondents from different World Health Organization regions and World Bank income groups. CONCLUSIONS: The six bellwether procedures identified can be used as markers of infrastructure capacity at various hospital levels, hence allowing targeted neurosurgical capacity-building in low-resource settings in order to avert disability and death from childhood neurosurgical disease.

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

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

The pathophysiology of pulmonary hypertension in left heart disease.

Pulmonary hypertension (PH) is characterized by elevated pulmonary arterial pressure leading to right-sided heart failure and can arise from a wide range of etiologies. The most common cause of PH, termed Group 2 PH, is left-sided heart failure and is commonly known as pulmonary hypertension with left heart disease (PH-LHD). Importantly, while sharing many clinical features with pulmonary arterial hypertension (PAH), PH-LHD differs significantly at the cellular and physiological levels. These fundamental pathophysiological differences largely account for the poor response to PAH therapies experienced by PH-LHD patients. The relatively high prevalence of this disease, coupled with its unique features compared with PAH, signal the importance of an in-depth understanding of the mechanistic details of PH-LHD. The present review will focus on the current state of knowledge regarding the pathomechanisms of PH-LHD, highlighting work carried out both in human trials and in preclinical animal models. Adaptive processes at the alveolocapillary barrier and in the pulmonary circulation, including alterations in alveolar fluid transport, endothelial junctional integrity, and vasoactive mediator secretion will be discussed in detail, highlighting the aspects that impact the response to, and development of, novel therapeutics.

Novel regulators of endothelial barrier function.

Endothelial barrier function is an essential and tightly regulated process that ensures proper compartmentalization of the vascular and interstitial space, while allowing for the diffusive exchange of small molecules and the controlled trafficking of macromolecules and immune cells. Failure to control endothelial barrier integrity results in excessive leakage of fluid and proteins from the vasculature that can rapidly become fatal in scenarios such as sepsis or the acute respiratory distress syndrome. Here, we highlight recent advances in our understanding on the regulation of endothelial permeability, with a specific focus on the endothelial glycocalyx and endothelial scaffolds, regulatory intracellular signaling cascades, as well as triggers and mediators that either disrupt or enhance endothelial barrier integrity, and provide our perspective as to areas of seeming controversy and knowledge gaps, respectively.

Intracranial aneurysms in patients with acute ischemic stroke prevalence and influence on mechanical thrombectomy over 14 years in a tertiary-care center.

INTRODUCTION: The prevalence of intracranial aneurysms (IA) in patients with acute ischemic stroke (AIS) requiring mechanical thrombectomy (MT) is unclear. OBJECTIVE: To describe the prevalence of IA in patients with AIS and their influence on MT. MATERIALS & METHODS: This is a retrospective cohort study on all patients admitted with a diagnosis of AIS from January 2008 to March 2022 at a tertiary academic center. The records were reviewed for demographic, clinical, imaging, and outcomes data. Only patients who had CTA at admission were included in this analysis. RESULTS: Among 2265 patients admitted with AIS, this diagnosis was confirmed in 2113 patients (93.3 %). We included 1111 patients (52.6 %) who had head CTA and 321 (28.9 %) who underwent MT. The observed prevalence of aneurysms on CTA was 4.5 % (50/1111 patients), and 8 (16 %) had multiple aneurysms. MT was performed in 7 patients harboring IAs: 6 ipsilateral (5 proximal and 1 distal to the occlusion)and 1 contralateral aneurysm.. The patient with a contralateral aneurysm had a TICI 2B score In patients with ipsilateral aneurysms, TICI 2B or 3 was achieved in 3 cases (50 %), which is significantly lower than historical control of MT (91.6 %) without IA (p = 0.01). No aneurysms ruptured during MT. The aneurysm noted distal to the occlusion was mycotic. CONCLUSION: In this analysis, the observed prevalence of IA in patients with AIS was 4.5%. Ipsilateral aneurysms (proximal or distal to the occlusion site) deserve particular attention, given the potential risk of rupture during MT. Aneurysms located distal to the occlusion were mycotic and the rate of recanization in patients with ipsilateral aneurysms was low compared to historical controls. Further studies are needed to improve the outcomes in patients with IA requiring MT.

Impact of the pandemic and concomitant COVID-19 on the management and outcomes of middle cerebral artery strokes: a nationwide registry-based study.

OBJECTIVES: To investigate the impact of the COVID-19 pandemic as well as concomitant COVID-19 itself on stroke care, focusing on middle cerebral artery (MCA) territory infarctions. DESIGN: Registry-based study. SETTING: We used the National Inpatient Sample (NIS) database, which covers a wide range of hospitals within the USA. PARTICIPANTS: The NIS was queried for patients with MCA strokes between 2016 and 2020. In total, 35 231 patients were included. OUTCOME MEASURES: Outcome measures were postprocedural complications, length of stays (LOSs), in-hospital mortality and non-routine discharge. Propensity score matching using all available baseline variables was performed to reduce confounders when comparing patients with and without concomitant COVID-19. RESULTS: Mechanical thrombectomy (MT) was performed in 48.4%, intravenous thrombolysis (IVT) in 38.2%, and both MT and IVT (MT+IVT) in 13.4% of patients. A gradual increase in the use of MT and an opposite decrease in the use of IVT (p<0.001) was detected during the study period. Overall, 25.0% of all patients were admitted for MCA strokes during the pandemic period (2020), of these 209 (2.4%) were concomitantly diagnosed with COVID-19. Patients with MCA strokes and concomitant COVID-19 were significantly younger (64.9 vs 70.0; p<0.001), had significantly worse NIH Stroke Severity scores, and worse outcomes in terms of LOS (12.3 vs 8.2; p<0.001), in-hospital mortality (26.3% vs 9.8%; p<0.001) and non-routine discharge (84.2% vs 76.9%; p=0.013), as compared with those without COVID-19. After matching, only in-hospital mortality rates remained significantly higher in patients with COVID-19 (26.7% vs 8.5%; p<0.001). Additionally, patients with COVID-19 had higher rates of thromboembolic (12.3% vs 7.6%; p=0.035) and respiratory (11.3% vs 6.6%; p=0.029) complications. CONCLUSIONS: Among patients with MCA stroke, those with concomitant COVID-19 were significantly younger and had higher stroke severity scores. They were more likely to experience thromboembolic and respiratory complications and in-hospital mortality compared with matched controls.

Combined anterior and posterior circulation approach for stent-assisted coiling of a recurrent basilar tip aneurysm.

Endovascular treatment of recurrent basilar aneurysms is challenging due to significant changes in the configuration of the aneurysm and adjacent vessels from prior interventions.1 Coil compaction is a common cause of recurrence and alters the aneurysm morphology significantly.2-4 Stenting of the basilar artery into a posterior cerebral artery modifies the angles between these vessels.5 In this video, we discuss a combined approach via the anterior and posterior circulation for stent-assisted coiling of a recurrent basilar tip aneurysm (Video 1) . A patient in their 40s with a history of ruptured aneurysm underwent multiple endovascular interventions including coiling, stent-assisted coiling, and Woven Endobridge (WEB) device. The patient presented with worsening headaches and underwent treatment with stent-assisted coiling for recurrence. After encountering challenges with direct access from the basilar artery, a combined anterior and posterior circulation approach was used.6 The stent was deployed through the posterior communicating artery and a snare was used to navigate the complex anatomy. neurintsurg;15/5/512/V1F1V1Video 1 .

Management of Intraventricular Meningiomas.

Intraventricular meningiomas (IVM) are intracranial tumors that originate from collections of arachnoid cells within the choroid plexus. The incidence of meningiomas is estimated to be about 97.5 per 100,000 individuals in the United States with IVMs constituting 0.7% to 3%. Positive outcomes have been observed with surgical treatment of intraventricular meningiomas. This review explores elements of surgical care and management of patients with IVM, highlighting nuances in surgical approaches, their indications, and considerations.

Falsely normal CT perfusion ischemic core readings are common and often associated with deep infarcts.

BACKGROUND: Proper identification of infarct extent is crucial for thrombectomy and prognostication. We sought to study the frequency and topographic aspects of those cases in which CT perfusion (CTP) misses a core lesion that is present on initial non-contrast CT (NCCT). METHODS: A review was carried out of a prospectively collected database of endovascular patients with anterior circulation large vessel occlusion strokes from January 2014 to November 2018. Patients with an e-ASPECTS <10 and adequate CTP maps were included. Total missed ischemic core (TMC) was defined as a CTP core lesion (relative cerebral blood flow <30%) <1 mL with a visualized hypodensity on NCCT. RESULTS: In total, 629 patients were analyzed of which 161 (25.6%) had a TMC. On univariate analysis, TMC was associated with isolated deep middle cerebral artery (MCA) strokes (77.6% vs 56.6%, p<0.001), lower National Institutes of Health Stroke Scale (NIHSS) score (9 (15-20) vs 17 (13-21), p=0.007) and longer times to treatment (452 (288-652) min vs 355 (236-655) min, p=0.03). After adjusting for identifiable confounders, isolated deep MCA stroke was an independent predictor of TMC (OR 2.49 (95% CI 1.63 to 3.8), p<0.001). There were no differences between patients presenting with a TMC and those not with good outcomes (modified Rankin Scale 0-2) (50.8% vs 47.6%, p=0.53) or 90-day mortality (23% vs 17.6%, p=0.17). However, TMC was associated with lower rates of any parenchymal hematomas (5.2% vs 14.6%, p=0.02; aOR 0.11 (95% CI 0.01 to 0.91), p=0.04) and smaller final infarct volumes (20.5 (11.3-42.9) mL vs 47.5 (20.3-85) mL, p<0.001). CONCLUSIONS: CTP may completely fail to detect ischemic core in as many as 25% of cases, especially in isolated deep MCA strokes. Technical refinements of the post-processing algorithms are therefore warranted. TMC infarcts may have a lower risk of reperfusion hemorrhage, potentially due to greater preservation of the neurovascular unit structure in face of delayed recovery of cerebral blood flow.

Sonolucent Cranioplasty in Extracranial to Intracranial Bypass Surgery: Early Multicenter Experience of 44 Cases.

BACKGROUND: The new sonolucent cranioplasty implant (clear polymethyl methacrylate, PMMA) adds functionality besides surgical reconstruction. One possible application uses the transcranioplasty ultrasound (TCUS) technique after PMMA cranioplasty to assess graft patency of extracranial-intracranial (EC-IC) bypass procedures. OBJECTIVE: To report our early multicenter experience. METHODS: This is a multicenter analysis of consecutive EC-IC bypass patients from 5 US centers (2019-2022) with closure postbypass using PMMA implant. RESULTS: Forty-four patients (median age 53 years, 68.2% females) were included. The most common indication for bypass was Moyamoya disease/syndrome (77.3%), and superficial temporal artery to middle cerebral artery bypass was the most common procedure (79.5%). Pretreatment modified Rankin Scales of 0 and 1 to 2 were noted in 11.4% and 59.1% of patients, respectively. Intraoperative imaging for bypass patency involved a combination of modalities; Doppler was the most used modality (90.9%) followed by indocyanine green and catheter angiography (86.4% and 61.4%, respectively). Qualitative TCUS assessment of graft patency was feasible in all cases. Postoperative inpatient TCUS confirmation of bypass patency was recorded in 56.8% of the cases, and outpatient TCUS surveillance was recorded in 47.7%. There were no cases of bypass failure necessitating retreatment. Similarly, no implant-related complications were encountered in the cohort. Major complications requiring additional surgery occurred in 2 patients (4.6%) including epidural hematoma requiring evacuation (2.3%) and postoperative surgical site infection (2.3%) that was believed to be unrelated to the implant. CONCLUSION: This multicenter study supports safety and feasibility of using sonolucent PMMA implant in EC-IC bypass surgery with the goal of monitoring bypass patency using TCUS.

Microsurgical Obliteration of Craniocervical Junction Dural Arteriovenous Fistulas: Multicenter Experience.

BACKGROUND: Dural arteriovenous fistulas (dAVFs) located at craniocervical junction are extremely rare (1%-2% of intracranial/spinal dAVFs). Their angio-architectural complexity renders endovascular embolization to be challenging given multiple small feeders with risk of embolysate reflux into vertebral artery and limited transvenous access. The available literature discussing microsurgery for these lesions is limited to few case reports. OBJECTIVE: To report a multicenter experience assessing microsurgery safety/efficacy. METHODS: Prospectively maintained registries at 13 North American centers were queried to identify craniocervical junction dAVFs treated with microsurgery (2006-2021). RESULTS: Thirty-eight patients (median age 59.5 years, 44.7% female patients) were included. The most common presentation was subarachnoid/intracranial hemorrhage (47.4%) and myelopathy (36.8%) (92.1% of lesions Cognard type III-V). Direct meningeal branches from V3/4 vertebral artery segments supplied 84.2% of lesions. All lesions failed (n = 5, 13.2%) or were deemed inaccessible/unsafe to endovascular treatment. Far lateral craniotomy was the most used approach (94.7%). Intraoperative angiogram was performed in 39.5% of the cases, with angiographic cure in 94.7% of cases (median imaging follow-up of 9.2 months) and retreatment rate of 5.3%. Favorable last follow-up modified Rankin Scale of 0 to 2 was recorded in 81.6% of the patients with procedural complications of 2.6%. CONCLUSION: Craniocervical dAVFs represent rare entity of lesions presenting most commonly with hemorrhage or myelopathy because of venous congestion. Microsurgery using a far lateral approach provides robust exposure and visualization for these lesions and allows obliteration of the arterialized draining vein intradurally as close as possible to the fistula point. This approach was associated with a high rate of angiographic cure and favorable clinical outcomes.

MIS lateral retroperitoneal transpsoas approach allows gross total resection of a giant L4 schwannoma.

In this surgical video, the authors present a successful minimally invasive (MIS) lateral retroperitoneal transpsoas approach for resection of an L4 nerve root schwannoma. They describe the surgical approach in detail, with special emphasis on patient positioning for an orthogonal view, as well as technical nuances throughout the procedure. Using a sequential tubular retractor, they performed a microscopic dissection of the lesion. The tumor was debulked and the tumor capsule was disconnected from the surrounding tissue. During dissection, direct stimulation identified a functional nerve root that was carefully dissected from the tumor capsule. The tumor was then removed en bloc. The video can be found here: https://stream.cadmore.media/r10.3171/2022.3.FOCVID2220.