The nasolabial approach: a potential alternative to the lip-splitting incision for maxillectomy

First described by Weber and later modified by Fergusson, the Weber-Fergusson incision has undergone numerous modifications, but the fundamental approach to maxillectomy has largely remained the same. We report the potential benefit of a nasolabial incision for partial maxillectomy. The incision is hidden within the nasolabial fold and obviates the need for division of the upper lip, which may undergo atrophy and shortening after radiotherapy.     

神经内镜辅助下经乙状窦后入路显微手术切除大中型听神经瘤

目的 探讨神经内镜辅助下经乙状窦后入路显微手术切除大中型听神经瘤的效果。方法 回顾性分析2019年5月至2022年5月神经内镜联合显微镜经乙状窦后入路手术治疗的16例大中型听神经瘤的临床资料。结果 16例肿瘤均全切除,面神经解剖保留14例（87.5%）,术后面神经功能依据House-Brackmann分级Ⅰ级5例,Ⅱ级6例,Ⅲ级3例。术后无脑脊液漏及颅内感染。术后随访3~24个月,复查MRI增强未见肿瘤复发。结论 神经内镜辅助显微手术切除切除大中型听神经瘤,有助于减少手术创伤,减少脑脊液漏等并发症,保护面听神经功能,提高肿瘤全切除率。     

前庭神经鞘膜瘤囊性变的治疗策略

摘要：目的分析前庭神经鞘膜瘤囊性变治疗策略的影响。方法回顾性分析2006年1月~2013年12月收治前庭神经鞘膜瘤697例,其中根据内听道及桥小脑角增强MRI发现为前庭神经鞘膜瘤束性变患者96例,同时从剩余601例中随机抽取96例作为实体肿瘤组,比较两组患者临床特性、术中特点和手术效果。结果前庭神经鞘膜瘤囊性变的临床进展明显较实性肿瘤快速,且听力症状较实性肿瘤患者严重,突发性耳聋率较高29（30.2%）,囊性肿瘤与面神经粘连较实体肿瘤严重,术后短期两组面神经功能差异无统计学意义（P>0.05）,但术后1年随访时CVS组面神经功能良好率明显低于SVS组（30.2% vs 44.8%,P=0.037）。两组在术后并发症发生率、死亡率、复发率方面无差异。结论前庭神经鞘膜瘤囊性变应首选手术切除,对于周围薄壁型囊性肿瘤,如剥离困难无法全切除,应以保留面神经功能为先,采取近全切除等措施,提高术后患者生活质量。     

Latency of vestibular responses of pursuit neurons in the caudal frontal eye fields to whole body rotation

The smooth pursuit system and the vestibular system interact to keep the retinal target image on the fovea by matching the eye velocity in space to target velocity during head and/or whole body movement. The caudal part of the frontal eye fields (FEF) in the fundus of the arcuate sulcus contains pursuit-related neurons and the majority of them respond to vestibular stimulation induced by whole body movement. To understand the role of FEF pursuit neurons in the interaction of vestibular and pursuit signals, we examined the latency and time course of discharge modulation to horizontal whole body rotation during different vestibular task conditions in head-stabilized monkeys. Pursuit neurons with horizontal preferred directions were selected, and they were classified either as gaze-velocity neurons or eye/head-velocity neurons based on the previous criteria. Responses of these neurons to whole body step-rotation at 20 degrees/s were examined during cancellation of the vestibulo-ocular reflex (VOR), VOR x1, and during chair steps in complete darkness without a target (VORd). The majority of pursuit neurons tested (approximately 70%) responded during VORd with latencies <80 ms. These initial responses were basically similar in the three vestibular task conditions. The shortest latency was 20 ms and the modal value was 24 ms. These responses were also similar between gaze-velocity neurons and eye/head-velocity neurons, indicating that the initial responses (<80 ms) were vestibular responses induced by semicircular canal inputs. During VOR cancellation and x1, discharge of the two groups of neurons diverged at approximately 90 ms following the onset of chair rotation, consistent with the latencies associated with smooth pursuit. The shortest latency to the onset of target motion during smooth pursuit was 80 ms and the modal value was 95 ms. The time course of discharge rate difference of the two groups of neurons between VOR cancellation and x1 was predicted by the discharge modulation associated with smooth pursuit. These results provide further support for the involvement of the caudal FEF in integration of vestibular inputs and pursuit signals.     

A Bayesian model of the disambiguation of gravitoinertial force by visual cues

The otoliths are stimulated in the same fashion by gravitational and inertial forces, so otolith signals are ambiguous indicators of self-orientation. The ambiguity can be resolved with added visual information indicating orientation and acceleration with respect to the earth. Here we present a Bayesian model of the statistically optimal combination of noisy vestibular and visual signals. Likelihoods associated with sensory measurements are represented in an orientation/acceleration space. The likelihood function associated with the otolith signal illustrates the ambiguity; there is no unique solution for self-orientation or acceleration. Likelihood functions associated with other sensory signals can resolve this ambiguity. In addition, we propose two priors, each acting on a dimension in the orientation/acceleration space: the idiotropic prior and the no-acceleration prior. We conducted experiments using a motion platform and attached visual display to examine the influence of visual signals on the interpretation of the otolith signal. Subjects made pitch and acceleration judgments as the vestibular and visual signals were manipulated independently. Predictions of the model were confirmed: (1) visual signals affected the interpretation of the otolith signal, (2) less variable signals had more influence on perceived orientation and acceleration than more variable ones, and (3) combined estimates were more precise than single-cue estimates. We also show that the model can explain some well-known phenomena including the perception of upright in zero gravity, the Aubert effect, and the somatogravic illusion.     

Vestibular contribution to the planning of reach trajectories

Reaching for an object while simultaneously rotating induces Coriolis and centrifugal inertial forces on the arm that require compensatory actions to maintain accuracy. We investigated whether the nervous system uses vestibular signals of head rotation to predict inertial forces. Human subjects reached in darkness to a remembered target 33 cm distant. Subjects were stationary, but experienced a strong vestibular rotation signal. We achieved this by rotating subjects at 360°/s in yaw for 2 min and then stopping, and subjects reached during the ‘post-rotary’ period when the deceleration is interpreted by the vestibular system as a rotation in the opposite direction. Arm trajectories were straight in control trials without a rotary stimulus. With vestibular stimulation, trajectory curvature increased an average of 3 cm in the direction of the vestibular stimulation (e.g., to the right for a rightward yaw stimulus). Vestibular-induced curvature returned rapidly to normal, with an average time constant of 6 s. Movements also became longer as the vestibular stimulus diminished, and returned towards normal length with an average time constant of 5.6 s. In a second experiment we compared reaching with preferred and non-preferred hands, and found that they were similarly affected by vestibular stimulation. The reach curvatures were in the expected direction if the nervous system anticipated and attempted to counteract the presence of Coriolis forces based on the vestibular signals. Similarly, the shorter reaches may have occurred because the nervous system was attempting to compensate for an expected centrifugal force. Since vestibular stimulation also alters the perceived location of targets, vestibular signals probably influence all stages of the sensorimotor pathway transforming the desired goal of a reach into specific motor-unit innervation.     

Papilledema secondary to vestibular schwannoma: An atypical case without intracranial hypertension

In most cases, vestibular schwannomas with papilledema are associated with intracranial hypertension secondary to hydrocephalus (obstructive or communicating). We describe the atypical case of a 39-years-old man who presented with bilateral papilledema revealing a vestibular schwannoma, but without hydrocephalus and with normal intracranial pressure. Ophtalmologic signs were completely resolved after tumor removal. The pathophysiological mechanism generally described to explain bilateral papilledema in such cases is tumor-induced hyperproteinorachia. However, in the absence of hydrocephalus or intracranial hypertension, this case raises the question of the mechanisms involved in the visual impairment related to vestibular schwannoma.     

新生爱校情感影响因素的调查与分析

目的通过调查新生入校前后对学校接纳程度的变化,以及影响新生爱校情感的场所、活动和人员情况,探究培养大学生爱校情感的途径。方法采用自编问卷调查内蒙古农业大学5个学院共470名新生爱校相关情况,对结果进行统计分析。结果新生入校后,对本校的接纳程度下降。新生对宿舍、食堂、管理、教学、自习以及对学生会干部、学办教师等的接纳程度,与他们对本校的接纳程度呈显著正相关。结论学校的场所、活动及学生会工作干部是新生爱校情感的重要影响因素,应采取综合措施培养新生的爱校情感,对提升学生的心理素质将起到很好的促进作用。     

经后外侧入路治疗胫骨平台后外侧骨折的效果观察

目的：探讨经后外侧入路治疗胫骨平台后外侧骨折的临床效果。方法选取本院2012年3月~2013年11月收治的胫骨平台后外侧骨折患者64例为观察对象,随机分为观察组与对照组,每组32例,观察组行经后外侧入路治疗,对照组行前外侧入路治疗,观察两组的骨折愈合情况、Rasmussen放射评分、膝关节功能恢复情况及并发症情况。结果所有患者均经6~12个月随访,骨折愈合率为100%。观察组的Rasmussen放射评分、HSS评分均高于对照组,并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论经后外侧入路治疗胫骨平台后外侧骨折的效果确切,其是较理想的入路方式。