视觉对人体姿势控制影响的脑功能网络连接机制

目的研究视觉对人体姿势控制影响及其脑功能网络连接机制。方法以15名健康青年为研究对象,要求受试者分别进行30 s睁眼、闭眼的双腿站立平衡,采集平衡过程中身体压力中心(center of pressure,COP)和脑电。对COP进行样本熵(SampleEn)计算;对脑电θ、α和β频段,计算相位滞后指数(phase lag index,PLI)构建大脑功能网络,并基于图论计算集聚系数(C)、特征路径长度(L)及小世界网络属性(σ)。结果人体在双腿站立平衡过程中,闭眼COPY样本熵显著高于睁眼(P<0.05)。闭眼α频段PLI平均值显著高于睁眼(P<0.05);闭眼α频段C、σ显著高于睁眼,L显著低于睁眼(P<0.05)。闭眼时α频段额区-中央区-顶区之间的网络连接以及中央区和顶区内连接强度显著高于睁眼(P<0.05)。闭眼时α频段PLI平均值以及C值与COPY样本熵中度呈中度负相关(P<0.05)。睁眼时左前额区、左顶区、左枕区α频段PLI平均值与COPY样本熵呈中度负相关;闭眼时左中央区、右枕区α频段PLI平均值则与COPY样本熵呈中度负相关。结论人体在站立平衡时,当没有视觉信息输入时,身体平衡稳定性下降,同时伴随着脑电α频段的脑网络连接增强以及大脑处理信息的效率需提升。人体在不同的视觉条件下进行姿势控制时,大脑会采用不同的神经策略。

动脉内溶栓治疗视网膜中央动脉阻塞患者的临床特征及功能性视觉恢复单中心研究

目的探讨动脉内溶栓(intra-arterial thrombolysis,IAT)治疗视网膜中央动脉阻塞(central retinal artery occlusion,CRAO)患者的临床特征及功能性视觉恢复情况。方法纳入2018年1月—2023年8月西北大学附属第一医院神经内科和神经眼科连续收治的非动脉炎性CRAO患者,根据入院后是否进行IAT治疗分为IAT组和非IAT组。功能性视觉定义为视力≥20/100。比较分析两组患者的临床特征和不同时间段(入院、出院时和出院1个月时)功能性视觉恢复情况。结果共纳入131例(131只眼)非动脉炎性CRAO患者,男性93例(71.0%),平均年龄为(61.6±12.6)岁,其中IAT组57例(43.5%),非IAT组74例(56.5%)。与非IAT组患者相比,IAT组患者年龄更低[(58.4±12.5)岁vs.(64.1±12.2)岁,P=0.011]、合并卒中病史者比例更低[10(17.5%)vs.25(33.8%),P=0.037]、发病至就诊时间更短[10.0(6.0~24.0)h vs.55.0(20.2~162.0)h,P<0.001]、醒后发病者比例更高[26(45.6%)vs.15(20.3%),P=0.002]和患侧颈内动脉血管状态更佳(无狭窄∶轻度狭窄∶中-重度狭窄∶闭塞=41∶7∶7∶2 vs.32∶11∶21∶10,P=0.006)。IAT组患者出院1个月时功能性视觉比例较非IAT组患者更高[25(43.9%)vs.18(24.3%),P=0.018],而入院和出院时差异无统计学意义(P>0.05)。多因素logistic回归分析显示,IAT组患者出院1个月时的功能性视觉较非IAT组患者显著改善(OR3.24,95%CI1.08~9.69,P=0.036)。IAT组患者术中发生眼动脉痉挛2例(3.5%)、穿刺部位皮肤出血2例(3.5%)和新发脑栓塞(均为无症状性栓塞)事件4例(7.0%)。结论是否进行IAT治疗的CRAO患者部分临床特征存在差异,IAT治疗可显著提高CRAO患者出院1个月时的功能性视觉,且手术安全性较好。提示临床医师需重视CRAO患者的IAT治疗,以期改善患者的视觉功能。

Neuro-rejuvenation for neuronal function

Neurodegenerative eye diseases, such as glaucoma, cause irreversible vision loss in millions of patients worldwide, creating serious medical, economic and social issues. Like other mammalian central nervous system tracts, optic nerve intrinsically lacks the capacity for axonal growth and its surrounding environment is also non-permissive to regeneration. Any axonal damage also triggers a vicious cycle of retinal ganglion cell （RGC） death. Exploring methods that can enhance RGCs survival and promote axonal regeneration will not only enable vision restoration for millions of patients, but also shed light on the treatment of other neurodegenerative diseases. In this review article, we will go through three current approaches to cure neu- rodegenerative eye diseases, including cell based therapy, neuro-regeneration and neuro-rejuvenation.

激光雷达和视觉传感器组合系统的在线校准方法

针对激光雷达和视觉传感器在车辆行驶过程中因振动发生漂移的问题,提出一种组合系统的在线校准方法。基于激光点云和图像的边缘匹配原理进行数据实时检测,检测到融合的传感器数据不准确时对其采取紧急措施,以提高车辆行驶安全性。针对未检测出错误的校准参数,采用梯度下降法优化成本函数,获取新的校准参数,实现传感器数据校正。通过数据集KITTI进行多次参数偏差实验,测试表明,算法可以检测较大的错误校准且能校正较小范围内的平移和旋转误差。

双视电力巡检机器人夜视图像的小波降噪研究

选取电力系统中应用广泛的双视巡检机器人,分析双目视觉机器人夜视巡检图像,针对视觉系统采集的电力设备图像进行中值滤波、特征提取、聚类分析。通过构造模糊阈值函数,提出小波阈值夜视图像降噪改进方法。通过数据分析,夜视图像降噪效果明显,为利用图像分析设备状态提供支撑。

消旋山莨菪碱联合角膜塑形镜减缓对轻中度近视眼患者的视功能影响

目的探讨与分析消旋山莨菪碱联合角膜塑形镜减缓对轻中度近视眼患者的视功能影响。方法选取2020年3月—2022年12月江苏省南通市海门区人民医院眼科收治的112例轻中度近视眼患者作为研究对象,根据1∶1随机掷硬币原则分为研究组与对照组,各56例。对照组佩戴角膜塑形镜治疗,研究组在此基础上给予消旋山莨菪碱治疗,对比两组视功能变化情况。结果治疗3个月后,两组裸眼视力高于治疗前,屈光度低于治疗前,并且研究组优于对照组,差异有统计学意义(P均<0.05)。治疗3个月后,研究组的总有效率为98.21%,优于对照组的85.71%,差异有统计学意义(χ^(2)=4.350,P<0.05)。治疗3个月后,两组的眼压均低于治疗前,并且研究组的眼压更低,差异有统计学意义(P<0.05)。研究组不良反应发生率为3.57%,低于对照组的17.86%,差异有统计学意义(χ^(2)=5.973,P<0.05)。结论消旋山莨菪碱联合角膜塑形镜治疗轻中度近视眼能提高患者的裸眼视力,降低屈光度,也可促进降低患者的眼压,降低不良反应发生率,从而改善患者的总体视功能。

视感知觉训练对间歇外斜视患儿术后视功能恢复的影响

目的:探讨间歇性外斜视患儿术后进行视感知觉训练的效果。方法:选取2020年4月至2023年4月郑州市第二人民医院收治的80例间歇性外斜视患儿作为研究对象,随机数字表法分为两组,每组各40例,对照组采取矫治术及配镜治疗,观察组在此基础上增加视感知觉训练,比较两组患儿的视功能、斜视度、知觉眼位偏移情况及立体视觉。结果:观察组术后7d视功能Ⅲ级37.50%,术后1个月Ⅲ级57.50%,6个月Ⅲ级82.50%,显著优于对照组(P<0.05)。观察组看近和看远的斜视棱镜度、斜视圆周度较对照组明显减小,融合范围较对照组明显增加(P<0.05)。术后1个月、6个月,观察组患儿知觉眼位的水平和垂直偏移显著低于对照组(P<0.05)。黄斑中心凹立体视比较,术后1个月观察组与对照组分别为60.00%、30.00%,术后6个月分别为65.00%、37.50%,差异有统计学意义(P<0.05);无立体视比较,术后1个月观察组与对照组分别为2.50%、25.00%,术后6个月分别为5.00%、25.00%,差异有统计学意义(P<0.05)。结论:针对间歇外斜视患儿实施视感知觉训练可促进术后视功能的改善,减小知觉眼位偏移程度,促进立体视觉恢复,防止眼位回退,减少无立体视觉。

基于双目视觉的水下动态目标识别与定位方法研究

针对动态水下目标跟踪定位过程需要良好的实时性与鲁棒性问题,提出一种基于双目视觉的水下动态目标定位方法;利用快速引导滤波提取水下图像的光照分量,构造了一种改进的二维伽马函数,并对其参数利用光照分量的分布特性进行调整,实现了对水下不同环境图像下的亮度自适应校正处理;利用卡尔曼滤波预估下一时刻目标的位置,将预测空间作为ROI区域进行图像校正,极大降低了算法的运行时间;在HSV空间对目标进行掩膜提取,识别之后通过双目定位算法对目标进行准确定位;经过水箱试验验证,与多尺度高斯函数、双边滤波等算法相比,该方法在运行速度上有着显著的提高,达到了35FPS,在定位过程中有着较高定位精度,在方向的平均相对误差为(3.59%,3.35%,1.42%);结果表明,该算法可以满足水下动态目标跟踪定位的实时性与鲁棒性要求。

Changes in brain function and anatomical structure following treatment of hyperbaric oxygen for visual pathway abnormalities in 16 cases Evaluation of functional magnetic resonance imaging combined with diffusion tensor imaging

BACKGROUND： There is a growing research focus on the combination of blood oxygenation level dependent functional magnetic resonance imaging （BOLD-fMRI） and diffusion tensor imaging （DTI） to evaluate visual cortical function and structural changes in the cerebrum, as well as morphological changes to the white matter fiber tracks, after visual pathway lesions. However, the combined application of BOLD-fMRI and DTI in treating of visual pathway abnormalities still requires further studies. OBJECTIVE： To observe and evaluate the effects of hyperbaric oxygen on visual pathway abnormalities, and to evaluate the characteristics of cerebral function and anatomic structural changes by using BOLD-fMRI combined with DTI technique. DESIGN： Case contrast observation. SETTING： Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA. PARTICIPANTS： Sixteen patients （9 males and 7 females, 15-77 years old） with lateral or bilateral visual disorder induced by visual pathway lesions were selected from the Department of Neurology, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from January 2006 to May 2007. These patients comprised the lesion group. Measures of interventional therapy： hyperbaric oxygen of two normal atmospheres for three courses （10 d/course） and routine internal medicine treatment. In addition, 12 healthy subjects of similar sex and age to the lesion group were regarded as the control group. The control group underwent routine ophthalmological and ocular fundus examinations; diagnostic results were normal. The experiment received confirmed consent from the local ethic committee, and all patients provided informed consent. METHODS： BOLD-fMRI and DTI manifestations in the lesion group were observed before and after hyperbaric oxygen intervention, and the results were compared with the control group. The subjects were positioned on their back, and BOLD-fMRI images were collected with the following GRE EPI sequence： TR = 2 000 ms, TE = 40 ms, layer thickness = 5 mm, and 20-layer successive scanning to cover the whole brain. While, DTI images were collected with SE EPI sequence of single excitation： TR=10 000 ms, TE = 112 ms, layer thickness = 4 mm, layer spacing = 0.5 mm, and a 30-layer successive scanning, matrix = 128×128. A diffusion gradient was applied at 13 directions, and one layer without diffusion weighted imaging was collected at b =1 000 s/mm^2. Numbers of activated voxels in cortical-activated regions, and fractional anisotropy in bilateral cerebral optical radiation regions, were calculated. Displacement, continuity, and destruction of fibrous tracts were analyzed. MAIN OUTCOME MEASURES： Results of BOLD-fMRI and DTI examinations. RESULTS： All 16 patients and 12 controls were included in the final analysis. ① Numbers of activated voxels through the use of BOLD-fMRI： prior to hyperbaric oxygen therapy, the number of activated voxels in the bilateral cortex of occipital lobe were significantly less in the lesion group than in the control group （t =3.23, P 〈 0.01）. In addition, the number of activated voxels significantly increased after treatment compared to before treatment （t = 2.46, P 〈 0.05）. ② Fractional anisotropy in optical radiation regions of bilateral cerebrum： fractional anisotropy in the lesion group was significantly less than the control group （t =2.89, P 〈 0.05）. In addition, fractional anisotropy after treatment was significantly higher than before treatment （t = 2.48, P 〈 0.05）. Moreover, fractional anisotropy of optical neuropathy was significantly higher in 6 patients in the lesion group than the occipital lobe optical central lesion （t = 2.35, P 〈 0.05）. CONCLUSION： BOLD-fMRI combined with DTI can indicate the occurrence, development, and therapeutic course of action for optical pathway lesions. The results acquired from these methods can provide information for function and structure, which can provide reliable verification in the treatment of cerebral function.

基于视觉的芯片位姿测量方法研究

针对芯片贴装过程中的偏移检测问题,提出一种基于视觉的芯片位姿测量方法。该方法首先对获取的芯片图像进行预处理;在获取像素级边缘的基础上,根据像素点灰度值,利用Sigmoid函数进行分类,准确定位芯片亚像素边缘,并对边缘异常点进行校正;最后,由已知的芯片尺寸对图像中的连通域进行计数,得到图像中的芯片个数,并通过重心坐标将芯片亚边缘划分为4个区域,采用最小二乘法分别进行拟合,获得芯片的位姿信息。实验结果表明,该方法具有一定的鲁棒性,且定位精度在0.5 pixel以内,运行时间约为0.4 s,满足实际生产中的贴装要求,具有一定的使用价值。

OMC框架下的行人多目标跟踪算法研究

多目标跟踪是计算机视觉领域被广泛研究的重要方向,但是在实际应用中,目标的快速移动、光照变化、遮挡等问题会导致跟踪性能变差,因此以多目标跟踪模型OMC为基础框架展开研究,以实现跟踪性能的进一步提升。针对多目标跟踪过程中存在的目标特征质量层次不齐的问题,对特征提取器进行优化,在主干网络集成了GAM注意力机制并在Neck网络部分更换了上采样方式;针对现有方法中存在的检测任务和重识别任务之间的“竞争问题”,构建了递归交叉相关网络,使得模型可以学习不同任务的特性和共性。此处针对两个子任务分别进行了优化,一是设计了新的通道注意力HS-CAM优化了重识别网络;二是更换了检测部分的边界回归损失函数,采用EIoU损失函数。实验表明,在MOT16数据集上MOTA指标可达73.5%,IDF1可达70.4%,MLgt为11.7%,相比较OMC算法减少了1.5个百分点。

An enhanced functional ability questionnaire(faVIQ) to measure the impact of rehabilitation services on the visually impaired

AIM: To develop a short,enhanced functional ability Quality of Vision(faVIQ) instrument based on previous questionnaires employing comprehensive modern statistical techniques to ensure the use of an appropriate response scale,items and scoring of the visual related difficulties experienced by patients with visual impairment. · METHODS: Items in current quality-of-life questionnaires for the visually impaired were refined by a multi-professional group and visually impaired focus groups. The resulting 76 items were completed by 293 visually impaired patients with stable vision on two occasions separated by a month. The faVIQ scores of 75 patients with no ocular pathology were compared to 75 age and gender matched patients with visual impairment. ·RESULTS: Rasch analysis reduced the faVIQ items to 27. Correlation to standard visual metrics was moderate(r =0.32-0.46) and to the NEI-VFQ was 0.48. The faVIQ was able to clearly discriminate between age and gender matched populations with no ocular pathology and visual impairment with an index of 0.983 and 95% sensitivity and 95% specificity using a cut off of 29.·CONCLUSION: The faVIQ allows sensitive assessment of quality-of-life in the visually impaired and should support studies which evaluate the effectiveness of low vision rehabilitation services.

New self-calibration approach to space robots based on hand-eye vision

To overcome the influence of on-orbit extreme temperature environment on the tool pose(position and orientation) accuracy of a space robot,a new self-calibration method based on a measurement camera(hand-eye vision) attached to its end-effector was presented.Using the relative pose errors between the two adjacent calibration positions of the space robot,the cost function of the calibration was built,which was different from the conventional calibration method.The particle swarm optimization algorithm(PSO) was used to optimize the function to realize the geometrical parameter identification of the space robot.The above calibration method was carried out through self-calibration simulation of a six-DOF space robot whose end-effector was equipped with hand-eye vision.The results showed that after calibration there was a significant improvement of tool pose accuracy in a set of independent reference positions,which verified the feasibility of the method.At the same time,because it was unnecessary for this method to know the transformation matrix from the robot base to the calibration plate,it reduced the complexity of calibration model and shortened the error propagation chain,which benefited to improve the calibration accuracy.

Application of Complementary Error Function to the Transition Zone of Myopic Ablation Shapes in Refractive Surgery

In refractive surgery, the cubic spline fit for the transition zone breaks down for myopia and myopic meridians in mixed astigmatism as in many cases the cubic spline function runs into negative values. In this paper, the complementary error function is proposed instead of the cubic spline function as the transition zone function, due to the availability of analytical expression of its derivatives and the nonnegativity fact. It is shown that with the use of the complementary error function, transition zones for all refractive types work correctly.

Virtual reality training improves balance function

Virtual reality is a new technology that simulates a three-dimensional virtual world on a com- puter and enables the generation of visual, audio, and haptic feedback for the full immersion of users. Users can interact with and observe objects in three-dimensional visual space without limitation. At present, virtual reality training has been widely used in rehabilitation therapy for balance dysfunction. This paper summarizes related articles and other articles suggesting that virtual reality training can improve balance dysfunction in patients after neurological diseases. When patients perform virtual reality training, the prefrontal, parietal cortical areas and other motor cortical networks are activated. These activations may be involved in the reconstruction of neurons in the cerebral cortex. Growing evidence from clinical studies reveals that virtual reality training improves the neurological function of patients with spinal cord injury, cerebral palsy and other neurological impairments. These findings suggest that virtual reality training can acti- vate the cerebral cortex and improve the spatial orientation capacity of patients, thus facilitating the cortex to control balance and increase motion function.

间歇性外斜视儿童术后视感知觉训练对各级视功能恢复的临床观察

目的:探讨视感知觉训练在间歇性外斜视(IXT)儿童患者术后各级视功能恢复以及知觉眼位改善中的作用。方法:前瞻性临床研究。收集2022-01/06就诊于兰州市第一人民医院眼科行斜视矫正手术且完成术后3mo随访的IXT患者74例。术后1d随机将患者分为2组:训练组35例患者进行双眼视感知觉训练,对照组39例患者不进行任何训练。观察两组患者术后1d, 3mo各级视功能和知觉眼位变化情况。结果:术后1d训练组有同时视者24例(69%),术后3mo同时视功能恢复患者为34例(97%),显著高于术后1d(P=0.002);术后3mo对照组有融合功能者22例(56%)、远立体视者13例(33%)、动态立体视者20例(51%)、静态精细立体视者17例(44%),训练组有融合功能者31例(89%)、远立体视者25例(71%)、动态立体视者30例(86%)、静态精细立体视者27例(77%),均显著高于对照组(均P<0.05);训练组患者知觉眼位偏移程度较对照组下降更明显(均P<0.05)。结论:IXT儿童患者术后进行视感知觉训练可以促进各级视功能恢复,并改善知觉眼位,提高大脑知觉水平对眼位的控制能力。

A Rare Case of Non-Functioning Pituitary Macroadenoma (NFMA)

NFMAs are benign tumors that do not produce any biologically active hormones and exceed 10 mm (0.39 in) in size. Although NFMAs are benign in origin, mass effects may lead to serious clinical symptoms such as visual impairments, chronic headache, and pituitary insufficiency. The authors describe a 51-year-old woman who had a NFMA (35 × 24 × 25 mm). The vision was reduced to 7/10 in the both eyes. A transnasal transsphenoidal surgery was performed and the tumor was successfully resected. Postoperatively, the patient had visual (9/10) and headache improvement. This case highlights a rare presentation of non-functioning pituitary macroadenoma.

虚拟操作系统在小鼠视觉疾病动物模型行为评估中的价值

视觉行为学检测是视觉疾病动物模型鉴定的主要方法之一,目前主要通过虚拟操作系统(VOS)产生视觉刺激诱发动物模型产生视动反应(OMR)或视动反射(OKR)来进行测量。自动化VOS能够调节光栅条纹宽度、旋转速度、光照强度等参数控制监测装置的对比敏感度和空间频率阈值,并追踪OKR、OMR及OKR联合OMR运动。通过对巩膜搜索线圈法、角膜标记法、OMR-arena系统、OMR指数、阶梯测试协议等测量方法及评估指标的不断完善与优化,图形二维刺激升级为三维刺激,并引入计算机图像识别技术提取小鼠身体及头部轮廓,利用深度学习等计算机算法,分析并处理疾病小鼠视觉行为学数据,提高灵敏度,缩短测量时间,减少检测误差,增加数据精准度,从而获得更可靠的视功能评估结果,为青光眼、白内障、视网膜病变、遗传性眼病、视神经退行性病变等疾病研究提供有力的研究工具。本文主要从视觉检测方法和视力评估指标2个方面对现有自动化VOS在小鼠视觉疾病模型行为评估中的价值进行综述。

视障辅助技术在低视力康复中的应用进展

因不同的眼部和神经性疾病,导致视觉功能严重受损,为低视力患者日常活动(如阅读及驾驶)及生活质量、心理健康带来严重的影响。人们对外界信息的感知主要来源于视觉,除威胁生命的重大疾病外,对人感官影响最大的损害当属视觉损伤。且随着人口日益老龄化,该问题日趋加重,低视力已成为目前全球范围内一个严重的公共卫生问题。目前,低视力康复发展面临着临床和科研的巨大挑战,要研发出一种能有效改善视觉功能,同时能兼顾多种功能的视障辅助技术,这需要医学、生物学、工程学、微电子学、计算机学等多学科的共同发展和相互合作。低视力康复通过为患者提供适宜的视障辅助技术,最大化利用患者的残余视力及视觉功能,改善与低视力相关的功能限制,有效改善其独立性和整体生活质量,使其独立生活、工作并融入社会成为可能。该文对经典的助视器、人工视觉(视觉假体/视觉感官替代设备)、经颅刺激及视觉生物反馈训练等视障辅助技术在低视力康复中的应用进展进行综述。

基于YOLOv5s改进的口罩佩戴检测算法

由于新型冠状病毒肺炎的爆发,口罩成为人们日常生活中必需品。为了识别与检测人们是否佩戴口罩,提出了一种基于改进的YOLOv5s口罩佩戴检测算法。通过在YOLOv5s主干网络引入改进的自适应的协调注意力机制模块(Coordinate attention-activate or not,CA-A)提升网络的特征提取能力,解决了错误检测和漏检的问题。以新的损失函数AD-CIoU代替CIoU损失函数,作为回归损失函数,提升了边界框的定位精确度。实验表明,与原始模型算法相比,所提出的模型算法平均精度mAP值达到96.1%,提升了1.7%,具有较好的检测精度,可以满足目标检测应用需求。