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.     

Axonal fusion via conduit-based delivery of hydrophilic polymers

Background

Hydrophilic polymers have been shown to improve physiologic recovery following repair of transected nerves with microsutures. Our study was designed to combine hydrophilic polymer therapy with nerve tubes (NT) to enhance polymer delivery to the site of nerve injury.

Methods

Using a rat sciatic nerve injury model, a single transection injury was repaired in an end-to-end fashion with NT + polyethylene glycol (PEG) to NT alone. Compound action potentials (CAPs) were recorded before nerve transection and after repair. Behavioral testing was performed for 5 weeks.

Results

PEG therapy restored CAPS in all, but one, animals, while no CAPS were recorded in animals not receiving PEG. Behavioral nerve function was measured using the standardized functional assessment technique and foot fault asymmetry scores (FF). FF scores were improved for the PEG therapy groups on postoperative days 7, 14, and 21. However, after expected eventual axonal outgrowth, the benefit was less noticeable at days 28 and 35. Immunohistochemistry of the distal axon segments showed an increase number of sensory and motor axons in the NT + PEG group as compared to NT alone.

Conclusion

These data suggest that PEG delivery via a conduit may provide a simple, effective way to fuse severed axons and regain early nerve function. For proximal nerve injuries in large animals, recovery of axonal continuity could dramatically improve outcomes, even if fusion only occurs in a small percentage of axons.     

“J”状塑型双腔气管导管插管操作对成功率及术后声音嘶哑、咽喉痛的影响

目的 观察双腔气管导管(double-lumen endotracheal tube,DLT)塑型对插管成功率及术后声音嘶哑(声嘶)、咽喉痛的影响,从而为寻求更好的DLT塑型插管提供依据. 方法 择期全身麻醉下行胸科手术患者160例,美国麻醉医师协会(ASA)分级Ⅰ～Ⅲ级,参照随机数字表法分成DLT插管塑型组和非塑型组(每组80例),两组根据左右DLT插管各分为两组(A、B、C、D组,每组40例),又根据性别再各分为两个亚组(A1、A2、B1、B2、C1、C2、D1、D2组,每组20例).两组均采用经口明视气管插管,塑型组采用塑成“J”状的DLT进行插管,非塑型组采用未经塑型保留原有弯度的DLT进行插管.观察DLT插管时间、插管尝试次数及插反情况,患者术后声嘶、咽喉痛发生率及严重程度. 结果 塑型组插管时间[(154±6)s]明显短于非塑型组[(185±13)s](P＜0.05);塑型组插管尝试次数[(1.4±0.4)次]明显少于非塑型组[(1.7±0.8)次](P＜0.05);塑型组插反情况(3次)明显比非塑型组少(11次)(P＜0.05),且与性别无关,但左DLT比右DLT易于插反(P＜0.05).患者术后声嘶发生率塑型组(15/80)明显低于非塑型组(33/80)(P＜0.05);患者术后咽喉痛发生率塑型组(15/80)明显低于非塑型组(31/80) (P＜0.05),且与性别有关,女性较男性术后易发生声嘶、咽喉痛. 结论 “J”状DLT塑型插管成功率高、刺激小,可降低患者术后声嘶、咽喉痛发生率,具有一定的临床推广意义.     

胆总管探查引流术后T管窦道形成的相关因素分析

目的 通过螺旋CT检查胆总管探查引流术后T管窦道的形成,探讨影响窦道形成的相关因素.方法 回顾性分析2011年5月至2013年12月右江民族医学院附属医院收治的465例行胆总管探查引流术患者的临床资料,术后2周行T管造影检查,判断有无胆道残留结石及狭窄,行螺旋CT检查T管窦道是否形成.选择患者性别、年龄、Alb、C反应蛋白、ALT、TBil、Hb、手术方式、T管周围积液、再次手术、糖尿病11个可能会影响窦道形成的因素进行分析.单因素分析采用x2检验,多因素分析采用Logistic回归.结果 465例患者T管造影均通畅,且无残留结石;CT检查发现397例患者术后2周形成完整窦道,即行T管拔除.对于窦道形成不完整或未形成的患者,术后4周复查CT判断窦道形成后拔除T管.所有患者均无胆汁漏发生,痊愈出院.单因素分析结果显示:Alb、手术方式、T管周围积液、糖尿病是影响T管窦道形成的因素(x2=50.750,7.671,19.022,15.373,P＜0.05);多因素分析结果显示:Alb＜ 30 g/L,腹腔镜手术、T管周围积液、糖尿病是影响T管窦道形成的独立危险因素(OR=1.135,0.493,0.262,0.363;95％CI:1.061 ～1.214,0.280～ 0.865,0.104～0.658,0.156 ～0.843,P＜0.05).结论 胆总管探查引流术后2周可通过CT检查判断T管窦道形成情况而决定是否拔除T管.Alb＜ 30 g/L、腹腔镜手术、T管周围积液、糖尿病是影响T管窦道形成的独立危险因素.     

Unexpected Rheology of Polydimethylsiloxane Liquid Blends

The rheological behaviour of polydimethylsiloxane (PDMS) liquid blends has been investigated both in rotational and oscillating mode. Liquid silicone rubbers based on PDMS at low, medium, and high viscosity have been used for low/high or medium/high liquid blends. The flow, viscosity, creep, and stress‐relaxation curves, strain‐spectra of temperature‐ or frequency‐sweep have been determined and the behaviour at slow shear rate investigated in detail. The low/high homologous blend shows an unexpected behaviour: the zero‐shear viscosity η₀ is higher, the compliance J ₀ lower and viscoelastic moduli G ₀, G(t), G′(ω) and G″(ω) higher, with respect to the components and medium/high blend. Moreover, the blend viscosity η(T), G′(T), and G″(T) exhibits an anomalous decreasing trend. The Entanglement Swelling Tube (EST) model is proposed. The nanosized chains swelled the entanglement of the long ones by means of dipolar interactions ? Si ^{δ +}–O ^{δ ?} in the sites between the blobs of the tube chains, where the free‐volume is highest. The linked entanglements are stabilized and the lifetime lengthened; the entanglement density increases at long deformation times. As the temperature rises, the anomalous behaviour is reduced due to the Entanglement Deswelling‐Solvation mechanism of short chains up to the transition to ordinary behaviour for T = 65 °C.     

硬膜下肿瘤的手术治疗、硬膜修补及术后脑脊液漏处理

目的　探讨硬膜下肿瘤术中硬膜的修复方法与术后脑脊液漏（cerebrospinal fluid leakage,CSFL）的关系。 方法　2010年1月至2016年12月采用后路手术治疗的硬膜下肿瘤200例,男89例,女111例,平均年龄46.2岁（4个月~ 82岁）。分析其影像学特点、术中留置内固定情况、硬膜修复方法、术后CSFL情况及其处理方法等资料,随访并予以总结。 结果　200例患者中26例（13%）术后出现CSFL。放置内固定85例,22例发生CSFL（25.9%）;未放置内固定115例,4例发生CSFL（3.5%）。单纯缝合硬膜30例,8例发生CSFL（26.7%）;缝合并覆盖脊柱膜136例,16例发生CSFL（11.8%）;缝合并覆盖脊柱膜和生物蛋白胶29例,2例发生CSFL（6.9%）;5例因硬膜缺损无法直接缝合,采用肌筋膜或脂肪修复,未发生CSFL。缝合硬膜后覆盖脊柱膜或/和生物蛋白胶、肌筋膜或脂肪的CSFL发生率与单纯连续缝合比较,差异有统计学意义（P<0.05）。26例CSFL患者中10例延长引流时间,未发生切口相关并发症,平均拆线时间（11.8±1.7）天;另16例患者早期即予拔除引流管,其中2例发生颅内感染,1例形成窦道,1例形成硬脊膜假性囊肿,平均拆线时间（18.5±8.5）天,差异有统计学意义（P<0.05）。 结论　硬膜下肿瘤术中放置内固定可增加CSFL的发生率,采用脊柱膜、生物蛋白胶、肌筋膜或脂肪修复硬膜可减少CSFL的发生。术后发生CSFL适当延长引流时间,可促进切口愈合,减少相关并发症的发生。     

Chornobyl,radiation, neural tube defects,and microcephaly

Pregnant women residing in areas impacted by the Chornobyl ionizing radiation of the Rivne Province in Ukraine have persistent higher levels of incorporated cesium-137. In these areas the neural tube defects and microcephaly rates are significantly higher than in areas with lower maternal cesium-137 incorporated levels. In two Rivne counties with populations proximal to nuclear power plants the rates of neural tube defects and microcephaly are the highest in the province. The neural tube defects rates in Rivne are persistently among the highest in Europe.     

改良体位在ICU人工气道患者留置胃管中的应用

目的 探讨改良体位(抬颌仰额)加导丝引导置管法在ICU人工气道患者留置胃管中的应用效果.方法 将实施人工气道的180例ICU住院患者按留置胃管顺序奇偶数分为对照组和观察组各90例,对照组采用常规体位加导丝引导置管法留置胃管,观察组采用改良体位加导丝引导置管法,观察两组一次性置管成功率、置管时间的差异.结果 观察组留置胃管一次性置管成功率显著高于对照组、置管时间显著短于对照组(均P＜0.01).结论 采用抬颌仰额位加导丝引导置管法能有效提高ICU人工气道患者留置胃管一次性置管成功率,缩短置管时间,进而减轻对患者食管损伤,提高护士工作效率.     

早期胃管与空肠营养管联合应用在急性重症胰腺炎治疗中的作用

目的探讨急性重症胰腺炎(severe acute pancreatitis,SAP)的治疗策略。方法先后对21例重症急性胰腺炎采用了个体化治疗的同时早期经鼻胃管及空肠营养管同时置入治疗。结果不但提高了重症急性胰腺炎的治愈率,同时缩短了病人住院时间,改善患者预后,减轻患者经济负担。结论早期经鼻胃管及空肠营养管同时置入治疗急性重症胰腺炎有效可行。