视神经鞘超声评估颅内高压的研究进展

颅内高压是临床常见的危重急症之一，严重影响患者脑功能甚至危及患者生命。故需迅速、准确的颅内压评估方法以及时采取临床干预和对后续治疗效果的评估。有创监测仍然是评估颅内压的金标准,然而,该方法存在如感染和出血等潜在风险。以往文献报道视神经鞘超声检查可以无创评估颅内高压。本文就此综述如下。     

Piezosurgical management of sealer extrusion‐associated mental nerve anaesthesia: A case report

The present report describes a case where sealer extrusion (Sealapex) occurred during root canal obturation of a left lower second premolar tooth, and the patient experienced sudden pain and followed by complete anaesthesia of the lower lip. After 3 weeks of conservative therapy and an unaltered anaesthesia period, piezosurgical removal of the extruded sealer and root‐end resection was performed despite the direct contact with the mental neurovascular bundle. At suture removal, 1 week after surgery, there was no improvement in sensation. Two weeks after the operation, the patient reported some changes, including a short paraesthesia period alternating with anaesthesia. At the fourth post‐operative week, neurosensory function recovered completely. This case represents successful use of the piezoelectric technique for mental nerve decompression and periapical surgery of a lower second premolar with close contact of the mental nerve.     

超声引导PVNB对老年食道癌开胸患者术后镇痛、应激及炎性因子水平的影响

目的 探讨超声引导下连续椎旁神经阻滞(PVNB)对老年食道癌开胸手术患者术后镇痛、应激及炎性因子水平的影响。方法 选取我院拟实施全麻下开胸手术的90例食道癌开胸手术患者作为研究对象,其中45例患者术前采用超声引导下PVNB麻醉复合全身麻醉(PVNB组)、对照组45例患者采用全身麻醉；两组患者术后均采用静脉自控镇痛(对照组)；对比两组患者术后2h、6h、24h及48h静息状态、咳嗽状态下的视觉模拟疼痛评分(VAS),术后镇痛药物用量及镇痛药物不良反应发生情况,术前及术后24h血清去甲肾上腺素(NE)、肾上腺素(E)、皮质醇(Cor)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)差异及术后肺部感染发生情况。结果 PVNB组患者和对照组在术后2h～术后48h的静息VAS评分及咳嗽VAS评分组间比较,差异具有统计学意义(P<0.05),PVNB组术后2h、6h及24h静息VAS评分及咳嗽VAS评分均高于对照组(P>0.05)。PVNB组患者术后的镇痛泵按压次数、舒芬太尼用量均低于对照组(P<0.05),PVNB组患者术后的镇痛泵按压次数、舒芬太尼用量均低于对照组(P<0.05),术前两组患者的血清NE、E、Cor水平差异无统计学意义(P>0.05)；术后两24h两组患者血清NE、E、Cor水平均较术前增高(P>0.05),术后24h PVNB组的血清NE、E、Cor水平低于对照组(P<0.05),术前两组患者的血清IL-6、TNF-α水平差异无统计学意义(P>0.05)；术后24h两组患者血清IL-6、IL-10、TNF-α水平均较术前增高(P<0.05),PVNB组的血清IL-6、TNF-α水平低于对照组(P<0.05),PVNB组术后发生肺部感染2例,发生率为4.4%,对照组术后发生肺部感染6例,发生率为13.3%,PVNB组术后肺部感染发生率低于对照组(P<0.05)。结论 超声引导下PVNB能够改善老年食道癌开胸患者术后镇痛效果,减轻手术创伤所致的应激反应,较少患者术后肺部感染的发生。     

Bands of Fontana are caused exclusively by the sinusoidal path of axons in peripheral nerves and predict axon path; evidence from rodent nerves and physical models

The precise cause of the bands of Fontana, striations on peripheral nerves visible to the naked eye, has been the subject of debate for hundreds of years. Some researchers have described them as reflecting the sinuous course of nerve fibres passing through nerves, and others have proposed that endoneurial collagen and sheaths surrounding nerves play a role in their appearance. We hypothesised that the bands are caused exclusively by reflection of light from the surfaces of nerve fibres travelling in phase in sinusoidal waveforms through peripheral nerves. We aligned images of obliquely illuminated nerves with confocal images of axons in those nerves, and the numbers and positions of the bands precisely matched the axonal waves. We also developed three‐dimensional models of nerves with representations of the sinusoidal path of axons at their surface. We observed patterns resembling the bands of Fontana when these models were obliquely illuminated. This provides evidence that the bands of Fontana can be caused by light reflected sinusoidal path of axons alone. We subsequently describe a mechanism of band production based on our observations of both nerves and models. We report that smaller diameter nerves such as phrenic nerves and distal branches of sciatic nerves have shorter band intervals than larger nerves, such as proximal trunks of sciatic nerves, and that shorter band intervals correlate with longer axons per unit length of nerve, which suggests a greater tolerance to stretch. Inspection of banding patterns on peripheral nerves may permit prediction of axon length within nerves, and assist in the interpretation of nerve conduction data, especially in diseases where axon path has become altered.     

Fractures of the humeral shaft

Fractures of the humeral shaft are relatively common and can occur in any a variety of age groups, and due to a variety of mechanisms of injury. The anatomy of the humeral shaft is vital to understand, to be able to plan management of these fractures: the intricate relationship of the radial nerve with the humeral shaft in particular, plays an important role in these fractures. Though non-operative measures are commonly employed for humeral shaft fractures routinely, there are some indications for operative management. There remain a variety of operative interventions available to a surgeon, all with pros and cons associated. This review aims to look in detail at the anatomy of the humeral shaft, the types and sites of fractures, the evidence and surgical methodology of the most common surgical interventions, including a discussion about the surgical complications, particularly a radial nerve palsy.     

Another (Internal) Epineurium: Beyond the Anatomical Barriers of Nerves

The epineurium has been accepted as the outer anatomical barrier of the peripheral nerves. Our objective was to characterize the microanatomy of the layers surrounding nerves using different tissue-specific staining methods. Two hundred forty-two cross sections of human sciatic and median nerves, and brachial plexuses of eight fresh unembalmed cadavers, were examined. The samples were fixed in formaldehyde solution and stained with hematoxylin–eosin, Masson's trichrome, or epithelial membrane antigen under standard conditions. Because epithelial membrane antigen only stains the perineurium, we demonstrated using hematoxylin–eosin and Masson's trichrome that there were different collagen layers inside and outside the nerves. All fascicles had a collagen layer that surrounded the perineurium and were in close contact with it, with no adipose tissue between them. Unlike the perineurium, this layer, an “internal epineurium,” contained no cells, and it surrounded one or a small group of fascicles. Bundling these fascicles or small groups of fascicles together was the true epineurium, and between the true and internal epineurium, we consistently found an adipose-containing compartment. More proximal to this, the tibial and common peroneal nerves were bundled together by another collagen layer, the circumneurium, which also had a fat-cell-containing compartment deep to it. There were scattered collagen fibers among the adipocytes. Using tissue-specific staining, we were able to demonstrate a collagen layer, the “internal epineurium.” Outside the nerves, we identified several fat-containing concentric compartments. Those compartments were limited by collagen fiber layers that were also similar to the epineurium. Clin. Anat. 33:199–206, 2020. © 2019 Wiley Periodicals, Inc.     

Effects of chronic methamphetamine abuse on the retinal nerve fiber layer,ganglion cell layer and Bruch’s membrane opening minimum rim width

BackgroundMethamphetamine (Meth) is a highly addictive and hallucinogenic agent which is used as the second most common illicit drug globally. Meth could affect the retina and optic nerve by inducing the release of vasoconstrictive agents such as endothelin 1 and induction of severe oxidative stress with accumulation of reactive oxygen species.AimTo evaluate the effects of chronic Meth abuse on the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL) and the Bruch’s membrane opening minimum rim width (MRW).MethodIn this case-control study, we recruited 55 Meth abusers and 49 healthy individuals with mean age of 44.63 ± 0.97 and 43.08 ± 0.91 years, respectively. RNFL thickness, GCL thickness and MRW were evaluated using optical coherence tomography.ResultsWe found statistically significant decrease in RNFL, MRW thickness in Meth abusers (P: 0.002 and P: 0.006, respectively). We did not detect statistically significant difference regarding GCL thickness between the groups (P = 0.320). Our results showed a weak but statistically significant correlation of Meth dose increment and decrement of RNFL thickness ((P: 0.005, r = -0.193) and MRW (P: 0.013, r = -0.174). We found no correlation between duration of Meth consumption with RNFL and MRW thickness (P: 0.205, r= -0.124; P: 0.771, r= -0.029, respectively).ConclusionWe found a statistically significant adverse association in meth abusers with RNFL thickness and MRW. These two parameters were also statistically associated with the meth dose as measured by daily dose of Meth. Although we found a decrease in the GCL thickness, it did not reach statistical significance.