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• Extent of resection (EOR) is independently predictive of VS progression, progression-free survival, and facial nerve outcomes. • Progression is also predicted by tumour size and Koos grade, facial outcomes also predicted by tumour size and patient age, and trigeminal outcomes are predicted only by preoperative trigeminal symptoms. • The effect of EOR on outcome is limited to Koos grade 4 tumours. • A small subset of five Koos grade 4 tumours are treated with subtotal resection and adjuvant radiotherapy with excellent tumour control and minimal morbidity. Vestibular schwannoma (VS) is the most common tumour of the cerebellopontine angle. Owing to complex anatomy and high rates of morbidity, surgical management of large tumours is challenging. We seek to explore the clinical landscape of VS to identify predictors of outcome and help guide surgical decision making. We retrospectively reviewed charts of patients who underwent primary surgery for VS between 2005 and 2020 at a quaternary referral center in Toronto, Canada. Mined data includes patient demographics, clinical presentation, radiological features, and treatment details. Regression modelling was used to identify predictors of tumour control, postoperative morbidity, and correlates of progression free survival (PFS). Two hundred and five tumours with sufficient data were included in our study. Syndromic NF2, large tumours (>3cm), subtotal resection (vs gross total resection), presence of edema on preoperative MRI, and preoperative trigeminal symptoms were all predictors of postoperative progression/need for further treatment; the latter four were also associated with shorter progression free survival. Extent of resection (EOR), tumour size, and Koos grade were independently predictive of postoperative progression/secondary intervention in multivariate models; however, only EOR was independently predictive of progression-free survival. EOR, tumour size, and patient age are each independently predictive of facial nerve outcome. We comprehensively explore the clinical landscape of surgically treated vestibular schwannoma and highlight important outcome predictors and disease subgroups. This may have important implications in risk stratifying these challenging cases. [ABSTRACT FROM AUTHOR]

To compare cement distribution and leakage for 2 bone cement–augmented screws with different designs of injection holes in patients and the impact of screw locations and bone mineral density (BMD) on the results. This study recruited 40 patients who underwent instrumentation with cement-augmented screws. Screw holes of group A were 4 holes located in the distal one third of screws, while screw holes of group B were 6 holes located in distal, middle, and proximal sites. Postoperative computed tomography images were obtained to evaluate the rate and type of cement leakage and the distribution pattern of cement. The lateral or center position of screw tip, BMD, and T-score were also analyzed for their influence on the results. Of 192 screws, 80 (41.7%) exhibited cement leakage on postoperative computed tomography. The incidence of cement distribution in the posterior half and type B leakage in group B was significantly higher compared with group A. In group A, the probability of cement distribution in the posterior half was significantly increased when the screw was laterally inserted. For both groups, the higher incidence of cement distribution in the posterior half was correlated with lower BMD and T-score. Our results showed that screws with injection holes closer to the screw tip had higher incidences of distribution in the anterior half of the body and lower incidences of type B leakage. Patients with lower BMD and T-scores should be closely monitored, and a more centered position is recommended for screw insertion. [ABSTRACT FROM AUTHOR]

Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare tumefactive lesion that can develop anywhere within the neuraxis. The incidence is likely underreported, given its nonspecific imaging features and because CAPNON has often been overwhelmed by the presence of comorbid disease. CAPNON is typically diagnosed by the histopathological examination findings. However, the histopathological diagnosis is often challenging owing to the existence of similar calcifying pathological entities. Although the pathogenesis of CAPNON has remained elusive, emerging evidence supports a reactive proliferative and immune-mediated process involving the aggregation of neurofilament light chain protein and the infiltration of immune cells. The management of CAPNON is largely dependent on the symptoms, which are mainly related to the location and associated mass effects. Maximal surgical resection will result in excellent patient outcomes with rare recurrence, especially in patients presenting with epilepsy. The discovery of neurofilament light chain protein within CAPNON suggests that neurofilament might be implicated in the pathogenesis of CAPNON, serve as an immunohistochemical marker to improve the diagnostic accuracy of CAPNON, and hold therapeutic potential for the treatment of CAPNON. [ABSTRACT FROM AUTHOR]

The endoscopic endonasal approach (EEA) has been increasing in popularity as an alternative to traditional transcranial and transorbital approaches in the treatment of orbital pathological entities. The purpose of the present study was to examine the outcomes of patients who had undergone EEA resection of orbital lesions at our center. We performed a retrospective medical record review of patients who had undergone the EEA for resection of orbital lesions and orbital apex decompression from January 1, 2006 to December 1, 2019. For all the patients, the demographic data, presenting symptoms, symptom duration, imaging data, operative details, and postoperative outcomes were collected and reviewed. Nine patients underwent endoscopic endonasal resection of orbital lesions and orbital apex decompression at our center, including 6 male patients and 3 female patients. The mean age was 49.4 years, and the mean follow-up period was 3.8 years (range, 1–13.5 years). The orbital pathological lesions that were treated included nasopharyngeal carcinoma, hemangioma, fibrous dysplasia, IgG4 pseudotumor, inverted papilloma, angioleiomyoma, adenocarcinoma, and neuroendocrine paraganglioma metastasis. All the patients presented with exophthalmos of the affected orbit. Of the 9 patients, 5 presented with decreased visual acuity on examination. Postoperatively, 1 of these 5 patients had improved to baseline visual acuity, 3 had stable vision, and 1 had brief improvement before experiencing progressive visual decline 1 month postoperatively. Two patients presented with diplopia, and both improved postoperatively. Three patients experienced new, transient, and self-limiting postoperative diplopia. For patients with orbital lesions causing compressive optic neuropathy, the endoscopic endonasal approach can be used as an alternative strategy in appropriately selected patients. [ABSTRACT FROM AUTHOR]

Spondylodiscitis is a challenging spinal disorder that requires surgical treatment only as a last resort. The use of various procedures and instruments remains controversial. In this retrospective study, we reported the safety and efficacy of a CaSO 4 drug carrier system for the transforaminal lumbar interbody fusion (TLIF) procedure for lumbar pyogenic spondylodiscitis. Thirty-four patients with lumbar spondylodiscitis underwent TLIF. CaSO 4 beads carrying vancomycin and gentamycin were implanted in the trajectory of screws and disc spaces. We measured markers of inflammation, scores of neurologic recovery, and quality of life. The fusion status was assessed at final follow-up and the correction of local and total lordotic angle was calculated. The patients were followed up for at least 12 months (range, 12–24 months). At 3 months follow-up, C-reactive protein levels and erythrocyte sedimentation rate returned to normal with no relapse. Nineteen patients with American Spinal Injury Association grade D preoperatively returned to American Spinal Injury Association grade E. The improvement on the visual analog scale and Oswestry Disability Index was 66.9% and 84.9%, respectively. At 12 months follow-up, 67.6% of patients achieved definitive union. The corrections of total and local lordotic angle were 10.02° ± 8.77° and 7.7° ± 8.75°, respectively. The rate of achievement of satisfactory Kirkaldy-Willis functional criteria was 85.3%. The combined use of single-level TLIF with a CaSO 4 drug delivery system was safe and effective for treatment of pyogenic lumbar spondylodiscitis. The system promoted reduction of inflammation with limited fixed segments without a negative impact on fusion status. This procedure may be considered a novel choice for spondylodiscitis, with more efficacy and less invasion. [ABSTRACT FROM AUTHOR]

Background Primary dural-based lymphoma is a rare disease entity. It has been hypothesized that patients with sarcoidosis are at increased risk of developing lymphoma, an association known as "sarcoidosis-lymphoma syndrome," although dural disease has not yet been reported in the literature. Case Description Here we report the first case of dural-based lymphoma in a 60-year-old man with a history of sarcoidosis, in keeping with sarcoidosis-lymphoma syndrome. His dural-based tumor was surgically resected. Pathology examination revealed a marginal zone B-cell lymphoma. Subsequent neural and systemic staging confirmed a localized lymphoma. The patient received local radiotherapy to control leptomeningeal disease. Conclusions Given the association between sarcoidosis and lymphoma, we suggest lymphoma to be considered as one of the top differentials for a dural-based mass lesion in patients with sarcoidosis. [ABSTRACT FROM AUTHOR]

Background The role of the extent of surgical resection (EOR) in clinical outcomes for patients with low-grade glioma requires further examination. The goal of the present study was to evaluate the association between variable degrees of EOR and clinical outcomes for patients with low-grade glioma. Methods We conducted a systematic review and meta-analysis and searched databases for reports of low-grade glioma EOR. Eligible studies compared patient outcomes, including ≥2 categories of EOR (biopsy, resection of any extent, subtotal resection [STR], or gross total resection [GTR]). Treatment effects were evaluated using pooled estimates, mean differences, or risk ratios (RRs) with corresponding 95% confidence intervals (CIs) using random effects modeling. Results Our literature search yielded 60 studies with 13,289 patients. Pooled estimates of overall survival (OS) showed an increase from 3.79 years in the biopsy group to 6.68 years in STR to 10.65 years in GTR. OS was favorable with resection of any extent compared with (mean difference, 3.24; 95% CI, 0.64–5.84; P = 0.015). Pooled estimates of seizure control showed an improvement from 47.8% with biopsy to 54.2% with STR and 81.0% with GTR. Compared with STR, GTR delayed malignant transformation (RR, 0.43; 95% CI, 0.20–0.93; P = 0.032), without increasing postoperative mortality (RR, 0.38; 95% CI, 0.07–1.97; P = 0.250) or morbidity (RR, 1.22; 95% CI, 0.65–2.28; P = 0.540). Conclusion Among patients with low-grade gliomas, greater degrees of safe EOR were associated with longer OS and progression-free survival, better seizure control, and delayed malignant transformation, without increasing mortality or morbidity. Highlights • Maximum safe resection is associated with increased OS. • Maximum safe resection is associated with increased PFS. • Patients undergoing maximum safe resection experienced delayed malignant transformation. • Mortality and morbidity associated with maximum safe resection were not different from those with STR. [ABSTRACT FROM AUTHOR]

Stroke is a major cause of morbidity and mortality worldwide, and intracranial stenoses increase the risk for stroke. Superficial temporal artery to middle cerebral artery bypass can be beneficial in selected patients with non-moyamoya steno-occlusive disease, however data is limited regarding the postoperative occurrence of hyperperfusion syndrome in this population. This case series describes the outcomes and complications, including hyperperfusion, in these patients who underwent bypass. This is a retrospective review of bypass procedures done for medically refractory intracranial stenosis at a single institution by a single surgeon between 2014 and 2021. 30 patients underwent 33 bypass procedures for unequivocal non-moyamoya steno-occlusive disease. All patients had immediate bypass patency on post-operative day one. Major perioperative complications (9%) included one stroke and two cases of hyperperfusion syndrome. Minor perioperative complications (12%) included two seizures, one superficial wound infection and one deep vein thrombosis. Modified Rankin Score improved in 20 patients (74%), worsened in one patient (4%), and remained stable in seven patients (22%) at the last follow up. Twenty-three patients (85%) had scores ≤ 2. The recurrent stroke rate was 3% at 30 days and 7% at two years. The bypass patency rate at one year was 87.5%. In this series, bypass for patients with medically refractory non-moyamoya steno-occlusive disease was well tolerated and effective, with overall favorable outcomes. The occurrence of hyperperfusion syndrome is rare but significant and should be considered in post-operative management of this population. [ABSTRACT FROM AUTHOR]

[Display omitted] The Enhanced Permeability and Retention (EPR) effect has been recognized as the central paradigm in tumor-targeted delivery in the last decades. In the wake of this concept, nanotechnologies have reached phenomenal levels in research. However, clinical tumors display a poor manifestation of EPR effect. Factors including tumor heterogeneity, complicating tumor microenvironment, and discrepancies between laboratory models and human tumors largely contribute to poor efficiency in tumor-targeted delivery and therapeutic failure in clinical translation. In this article, approaches for evaluation of EPR effect in human tumor were overviewed as guidance to employ EPR effect for cancer treatment. Strategies to augment EPR-mediated tumoral delivery are discussed in different dimensions including enhancement of vascular permeability, depletion of tumor extracellular matrix and optimization of nanoparticle design. Besides, the recent development in alternative tumor-targeted delivery mechanisms are highlighted including transendothelial pathway, endogenous cell carriers and non-immunogenic bacteria-mediated delivery. In addition, the emerging preclinical models better reflect human tumors are introduced. Finally, more rational applications of EPR effect in other disease and field are proposed. This article elaborates on fundamental reasons for the gaps between theoretical expectation and clinical outcomes, attempting to provide some perspective directions for future development of cancer nanomedicines in this still evolving landscape. [ABSTRACT FROM AUTHOR]

The domestic combustion of smoky (bituminous) coal in the Chinese counties of Xuanwei and Fuyuan, are responsible for some of the highest rates of lung cancer in the world. Cancer rates vary between coal producing regions (deposits) in the area, with coals from Laibin exhibiting particularly high risks and smokeless (anthracite) coal exhibiting lower risks. However, little information is available on the specific burning characteristics of coals from throughout the area. We conducted an extensive controlled burning experiment using coal from multiple deposits in either a traditional firepit or ventilated stove, accompanied by a detailed examination of time-weighted and real-time size-aggregated particle concentrations. Smoky coal caused higher particle concentrations of all sizes than smokeless coal, with variations observed by geological source. Virtually all particle emissions were in the PM 2.5 fraction (98% - mass based), and 75% and 46% were in the PM 1 and PM 0.3 fraction respectively. Real-time concentrations of PM 1 and PM 0.1 peaked after coal was added and declined afterwards. Ventilation reduced particle concentrations by up to 15-fold and increased the coal burning rate by 1.9-fold. These findings may provide valuable insight for reducing exposure and adverse health effects associated with domestic coal combustion. [Display omitted] • Both historical (from 1980s) and recent (2010–2017) coal samples were tested. • Particle size-distribution and stove/fuel efficiencies were reported. • Particle emission levels varied by coal geological sources. • Stove improvements reduced indoor particle emissions of all sizes from coal. • Stove improvements promoted cooking efficiency. [ABSTRACT FROM AUTHOR]

In recent years, correlation filters have achieved excellent performance in terms of accuracy and robustness for visual target tracking. However, it is still a challenging task to improve the tracking capability which can handle complex background and deal with target scale changes. In this paper, a new tracker based on the correlation filter framework with scale adaptation for visual target tracking is presented: 1) an effective scale adaptive scheme, which can solve the fixed template size with the basis of traditional correlation filter tracker, is proposed; 2) two powerful features including histogram of oriented gradient and color name, which can improve the overall tracking performance, are integrated together; 3) a high-confidence model updating strategy, which can avoid the model occlusion problem during model updating, is developed. The extensive experimental evaluations on OTB-2013 dataset have demonstrated that the developed novel tracker in our study can successfully outperform the other trackers on the benchmark dataset with 51 sequences. It is very promising for various challenging scenarios. [ABSTRACT FROM AUTHOR]

Sellar arachnoid cysts (SACs) are rare lesions that require treatment only if symptomatic. The endoscopic endonasal approach has been widely used. Despite their simple cystic appearance and the straight-forward surgical intervention, important associated risks exist, with cerebrospinal fluid (CSF) leak the prevalent risk. A retrospective analysis of patients with pathologically confirmed SAC between January 2006 and December 2019 was conducted. A homogeneous simple cyst-opening technique and skull base reconstruction with nasoseptal flaps was used. A total of 10 patients were identified (7 women and 3 men; median age, 54.5 years; range, 20–77 years). Of the 10 patients, 8 had had newly diagnosed SACs and 2 patients had had recurrence from a previously microsurgically fenestrated SAC. Eight patients had presented with visual symptoms, one with visual symptoms and fatigue, and one with intractable headaches. Neuro-ophthalmological and endocrinological assessments had revealed visual field deficits in 6, visual acuity decline in 5, and hypopituitarism in 2 patients. The median calculated volume was 1.71 mL (range, 0.27–2.54 mL). Postoperatively, no CSF leak and no further surgical complications were noted. The visual field had improved in 4 of 6 patients and visual acuity had improved in 4 of 5 patients. Anterior pituitary function had improved in 1, worsened in 1, and remained stable in 8 patients. One patient had developed diabetes insipidus. One recurrence was recorded at 54 months postoperatively. The results from the present study have shown that SACs can be effectively treated using a simple cyst-opening technique. The routine use of nasoseptal flaps significantly reduced the risk of CSF leakage without compromising nasal quality of life in the long term or mandating additional incisions. Long-term follow-up is important to monitor for late recurrence. [ABSTRACT FROM AUTHOR]

Household air pollution (HAP) from indoor combustion of solid fuel is a global health burden linked to lung cancer. In Xuanwei, China, lung cancer rate for nonsmoking women is among the highest in the world and largely attributed to high levels of polycyclic aromatic hydrocarbons (PAHs) that are produced from combustion of smoky (bituminous) coal used for cooking and heating. Epigenetic age acceleration (EAA), a DNA methylation-based biomarker of aging, has been shown to be highly correlated with biological processes underlying the susceptibility of age-related diseases. We aim to assess the association between HAP exposure and EAA. We analyzed data from 106 never-smoking women from Xuanwei, China. Information on fuel type was collected using a questionnaire, and validated exposure models were used to predict levels of 43 HAP constituents. Exposure clusters were identified using hierarchical clustering. EAA was derived for five epigenetic clocks defined as the residuals resulting from regressing each clock on chronological age. We used generalized estimating equations to test associations between exposure clusters derived from predicted levels of HAP exposure, ambient 5-methylchrysene (5-MC), a PAH previously found to be associated with risk of lung cancer, and EAA, while accounting for repeated-measurements and confounders. We observed an increase in GrimAge EAA for clusters with 31 and 33 PAHs reflecting current (β = 0.77 y per standard deviation (SD) increase, 95 % CI:0.36,1.19) and childhood (β = 0.92 y per SD, 95 % CI:0.40,1.45) exposure, respectively. 5-MC (ng/m3-year) was found to be associated with GrimAge EAA for current (β = 0.15 y, 95 % CI:0.05,0.25) and childhood (β = 0.30 y, 95 % CI:0.13,0.47) exposure. Our findings suggest that exposure to PAHs from indoor smoky coal combustion, particularly 5-MC, is associated with GrimAge EAA, a biomarker of mortality. [ABSTRACT FROM AUTHOR]

We previously showed that exposure to 5-methylchrysene (5MC) and other methylated polycyclic aromatic hydrocarbons (PAHs) best explains lung cancer risks in a case-control study among non-smoking women using smoky coal in China. Time-related factors (e.g., age at exposure) and non-linear relations were not explored. We investigated the relation between coal-derived air pollutants and lung cancer mortality using data from a large retrospective cohort. Participants were smoky (bituminous) or smokeless (anthracite) coal users from a cohort of 42,420 subjects from four communes in XuanWei. Follow-up was from 1976 to 2011, during which 4,827 deaths from lung-cancer occurred. Exposures were predicted for 43 different pollutants. Exposure clusters were identified using hierarchical clustering. Cox regression was used to estimate exposure–response relations for 5MC, while effect modification by age at exposure was investigated for cluster prototypes. A Bayesian penalized multi-pollutant model was fitted on a nested case-control sample, with more restricted models fitted to investigate non-linear exposure–response relations. We confirmed the strong exposure–response relation for 5MC (Hazard Ratio [95% Confidence Interval] = 2.5 [2.4, 2.6] per standard-deviation (SD)). We identified four pollutant clusters, with all but two PAHs in a single cluster. Exposure to PAHs in the large cluster was associated with a higher lung cancer mortality rate (HR [95%CI] = 2.4 [2.2, 2.6] per SD), while exposure accrued before 18 years of age appeared more important than adulthood exposures. Results from the multi-pollutant model identified anthanthrene (ANT) and benzo(a)chrysene (BaC) as risk factors. 5MC remained strongly associated with lung cancer in models that included ANT and BaC and also benzo(a)pyrene (BaP). We confirmed the link between PAH exposures and lung cancer in smoky coal users and found exposures before age 18 to be especially important. We found some evidence for the carcinogen 5MC and non-carcinogens ANT and BaC. [ABSTRACT FROM AUTHOR]

Background Context: Imaging modalities used to visualize spinal anatomy intraoperatively include X-ray studies, fluoroscopy, and computed tomography (CT). All of these emit ionizing radiation.Purpose: Radiation emitted to the patient and the surgical team when performing surgeries using intraoperative CT-based spine navigation was compared.Study Design/setting: This is a retrospective cohort case-control study.Patient Sample: Seventy-three patients underwent CT-navigated spinal instrumentation and 73 matched controls underwent spinal instrumentation with conventional fluoroscopy.Outcome Measures: Effective doses of radiation to the patient when the surgical team was inside and outside of the room were analyzed. The number of postoperative imaging investigations between navigated and non-navigated cases was compared.Methods: Intraoperative X-ray imaging, fluoroscopy, and CT dosages were recorded and standardized to effective doses. The number of postoperative imaging investigations was compared with the matched cohort of surgical cases. A literature review identified historical radiation exposure values for fluoroscopic-guided spinal instrumentation.Results: The 73 navigated operations involved an average of 5.44 levels of instrumentation. Thoracic and lumbar instrumentations had higher radiation emission from all modalities (CT, X-ray imaging, and fluoroscopy) compared with cervical cases (6.93 millisievert [mSv] vs. 2.34 mSv). Major deformity and degenerative cases involved more radiation emission than trauma or oncology cases (7.05 mSv vs. 4.20 mSv). On average, the total radiation dose to the patient was 8.7 times more than the radiation emitted when the surgical team was inside the operating room. Total radiation exposure to the patient was 2.77 times the values reported in the literature for thoracolumbar instrumentations performed without navigation. In comparison, the radiation emitted to the patient when the surgical team was inside the operating room was 2.50 lower than non-navigated thoracolumbar instrumentations. The average total radiation exposure to the patient was 5.69 mSv, a value less than a single routine lumbar CT scan (7.5 mSv). The average radiation exposure to the patient in the present study was approximately one quarter the recommended annual occupational radiation exposure. Navigation did not reduce the number of postoperative X-rays or CT scans obtained.Conclusions: Intraoperative CT navigation increases the radiation exposure to the patient and reduces the radiation exposure to the surgeon when compared with values reported in the literature. Intraoperative CT navigation improves the accuracy of spine instrumentation with acceptable patient radiation exposure and reduced surgical team exposure. Surgeons should be aware of the implications of radiation exposure to both the patient and the surgical team when using intraoperative CT navigation. [ABSTRACT FROM AUTHOR]