Endonasal Skull Base Tumor Removal Using Concentric Tube Continuum Robots: A Phantom Study

Objectives The purpose of this study is to experimentally evaluate the use of concentric tube continuum robots in endonasal skull base tumor removal. This new type of surgical robot offers many advantages over existing straight and rigid surgical tools including added dexterity, the ability to scale movements, and the ability to rotate the end effector while leaving the robot fixed in space. In this study, a concentric tube continuum robot was used to remove simulated pituitary tumors from a skull phantom. Design The robot was teleoperated by experienced skull base surgeons to remove a phantom pituitary tumor within a skull. Percentage resection was measured by weight. Resection duration was timed. Setting Academic research laboratory. Main Outcome Measures Percentage removal of tumor material and procedure duration. Results Average removal percentage of 79.8 ± 5.9% and average time to complete procedure of 12.5 ± 4.1 minutes (n = 20). Conclusions The robotic system presented here for use in endonasal skull base surgery shows promise in improving the dexterity, tool motion, and end effector capabilities currently available with straight and rigid tools while remaining an effective tool for resecting the tumor.     

Meningiomas of the Pediatric Skull Base: A Review

Pediatric skull base meningiomas are rare and complex clinical entities. Meningioma is a relatively uncommon brain tumor in children, and only ∼ 27% involve the skull base. Some evidence suggests that these tumors are more likely to be atypical or malignant in children than adults. The absence of female preponderance in pediatric meningiomas is reflected in the skull base subpopulation. Skull base meningiomas in children are most likely to be found in the anterior or middle fossa base, or involving the orbit and optic nerve sheath. Petroclival, suprasellar/parasellar, cerebellopontine angle, cavernous sinus, and foramen magnum tumors are very rare. Meningiomas constitute a small proportion of reported cases of pediatric skull base pathology, and they are entirely absent from many case series. Initial gross total resection is consistently associated with superior outcomes. Surgical approaches to the pediatric skull base must take additional factors into consideration including relatively smaller anatomy, immature dentition, incompletely aerated sinuses and air cells, and altered configurations of structures such as the pterional bony complex. Multidisciplinary expertise is essential to optimizing treatment outcomes.     

The Costs of Skull Base Surgery in the Pediatric Population

Objectives To determine the costs of endoscopic endonasal surgery (EES) for pediatric skull base lesions. Methods Retrospective chart review of pediatric patients (ages 1 month to 19 years) treated for skull base lesions with EES from 1999 to 2013. Demographic and operative data were recorded. The cost of care for the surgical day, intensive care unit (ICU), floor, and total overall cost of inpatient stay were acquired from the finance department. Results A total of 160 pediatric patients undergoing EES for skull base lesions were identified. Of these, 55 patients had complete financial data available. The average total inpatient and surgical costs of care were $34, 056 per patient. Angiofibromas were the most costly: $59,051 per patient. Fibro-osseous lesions had the lowest costs: $10,931 per patient. The average ICU stay was 1.8 days at $4,577 per ICU day. The average acute care stay was 3.4 days at $1,961 per day. Overall length of stay was 4.5 days. Three cerebrospinal fluid leaks (4%) and two cases of meningitis (3%) occurred. One tracheostomy was required (1.5%). Conclusions EES is a cost-effective model for removal of skull base lesions in the pediatric population. Costs of care vary according to pathology, staged surgeries, length of ICU stay, and need for second operations.     

Esthesioneuroblastoma: An Update on the UCLA Experience, 2002–2013

Objectives To profile the clinical presentation and treatment results of esthesioneuroblastomas at the University of California, Los Angeles (UCLA), from 2002 to 2013. Design Retrospective review. Setting Tertiary academic institution. Participants Forty-one patients with esthesioneuroblastomas treated at UCLA. Main Outcome Measures Overall survival (OS) and recurrence-free survival (RFS). Results Thirty-six patients were included with a mean age of 50.1 years and a median duration of follow-up of 33 months. The 5-year RFS and OS were 54% and 82%, respectively. Modified Kadish stage was the only factor identified to affect OS. Multivariate analysis demonstrated that tumor grade was the only factor that had an independent impact on RFS. There was no statistical difference in survival among the surgical approaches chosen. Conclusions The updated data on the UCLA experience reveals that all three surgical approaches chosen provide comparable survival, although longer follow-up will be needed to ascertain if these findings hold true. The endoscopic approach had a statistically significant decrease in length of hospital stay and a trend toward reduced blood loss, intensive care unit admission, and complications. The modified Kadish staging was the only factor identified to predict OS. Multivariate analysis revealed that tumor grade was an independent predictor of recurrence; therefore, its importance should be emphasized in future staging systems.     

中医哮喘领域本体的构建

目的:利用本体的方式实现中医哮喘领域的知识的共建共享及推理。方法:通过对中医文献中"哮喘"相关知识的提取,基于斯坦福大学的七步法构建了"哮喘"的疾病本体,实现了哮喘相关知识的领域建模,建立了部分概念与概念间的关系约束及公理。结果:中医哮喘领域本体构建完成能够实现知识的共享以及简单的推理。共有类120个,实例425个,对象属性18个,其中反向属性6个,数值属性2个,等价类公理1个,子类公理138个,基本实现了对哮喘领域知识的语义化表达。结论:本体的构建在知识的共建、共享及未来知识库的语义检索、数据挖掘中具有一定的参考与应用价值。     

Recurrent ameloblastoma in the anterior skull base： Report of 3 cases

Ameloblastoma is a benign but locally invasiveepithelial odontogenic tumor. Recurrence ofameloblastoma is most common after inadequate treat-ment, with an incidence up to 90% in the mandibleand 100% in the maxilla[1]. Despite radical resectionsincluding adjacent soft tissues, a recurrence rate of5% to 15% has been reported[2]. However, only a fewcases of recurrence reported in the literature involvedthe temporal fossa [3～5]. We presented 3 patients withrecurrent ameloblastoma in the anterior …     

263例患者固定修复后基牙情况5年临床观察

目的 探索固定义齿修复后基牙的发病规律.方法 随访观察263例行固定义齿修复的患者,修复5年来基牙的发病情况,分析患者年龄、修复体材料、修复时间与基牙发病的关系.结果 41岁以上年龄组患者修复后基牙发病明显高于40岁以下年龄组;基牙发病与修复体材料无关;修复后第1年基牙发病明显高于其后4年.结论 固定修复后有一定数量的基牙发生牙髓病和根尖周病,基牙发病与患者年龄及修复体戴用的时间有关,但与修复体材料无关.     

The evolution of the complete denture base. Theories of complete denture retention — A review. Part 1

The history of denture base materials and the accompanying development of impression techniques are traced from the earliest times to the present day (Part 1) as a prelude to a study (Part 2–4) of the various theories that have been advanced to explain retention of the base without mechanical support. These theories are critically reviewed and tabulated in chronological order. Some areas for further investigation are identified.     

义齿塑料基托热压灌注成型新工艺—颜色稳定性的比较研究

目的：分析比较成型后的基托塑料可能发生的变色。方法：对不同粉、液比例灌注成型的基托塑料和常规模压成型的基托塑料，用分光测色仪观察颜色稳定性。结果：粉、液以２∶１体积比灌注成型的义齿基托，表面平整光滑，色调、饱和度与常规模压成型的义齿基托相同，而其表面可抛光性优于常规法。结论：２种方法成型的义齿基托对紫外线的敏感性无显著性差异。     

The effect of two fibre impregnation methods on the cytotoxicity of a glass and carbon fibre-reinforced acrylic resin denture base material on oral epithelial cells and fibroblasts

Acrylic resin dentures may have cytotoxic effects on oral soft tissues. However, there is sparse data about the cytotoxic effect of fibre-reinforced acrylic resin denture base materials. The purpose of this in vitro study was to determine the effect of two fibre impregnation methods on the cytotoxicity of a glass and carbon fibre-reinforced heat-polymerized acrylic resin denture base material on oral epithelial cells and fibroblasts. One hundred acrylic resin discs were assigned to five experimental groups (n = 20). One of the groups did not include any fibre. Two groups consisted of silane and monomer treated glass fibres (Vetrolex) impregnated into acrylic resin (QC-20) discs. The other two groups consisted of silane and monomer treated carbon fibres (Type Tenox J, HTA). Untreated cell culture was used as positive control. The human oral epithelial cell line and buccal fibroblast cultures were exposed to test specimens. The cytotoxicity of the test materials was determined by succinic dehydrogenase activity (MTT method) after 24 and 72 h exposures. Data were analysed with a statistical software program (SPSSFW, 9.0). A one-way analysis of variance (anova) test and Bonferroni test were used for the comparisons between the groups. All statistical tests were performed at the 0.95 confidence level (P < 0.05). After 24 and 72 h incubation, cell viability percentages of all experimental groups showed significant decrease according to the positive control cell culture. Fibroblastic cell viability percentages of silane and monomer treated fibre-reinforced groups were lower than the unreinforced group. Cell viability of monomer-treated groups displayed the lowest percentages. Elapsed incubation time decreased epithelial cell viability in silane-treated groups. Fibroblastic cell viability was not influenced by elapsed time except the unreinforced group.