视觉诱发电位对视神经挫伤早期诊断的应用价值

目的探讨视觉诱发电位(VEP)对外伤性视神经挫伤的早期诊断的应用价值。方法对56例经临床诊断为外伤性视神经挫伤的患者行VEP检查。结果比较视神经挫伤患者受伤眼与自身健眼的VEP结果。受伤眼VEP的P100波的振幅、潜伏期有不同程度的异常。患者视力损伤越严重,P100波的改变越明显。VEP检查能灵敏地反映视神经的损伤程度。结论 VEP能为外伤性视神经挫伤的早期临床诊断、视功能评价提供客观依据。     

图形翻转视觉诱发电位在视神经管减压后视神经损伤不同时期的变化特征

目的:观察视神经损伤动物模型在损伤后和不同时期视神经管减压后视觉诱发电位的变化,了解创伤性视神经损伤的手术时机与疗效的关系。方法:实验于2005-03/05在解放军南京军区南京总医院动物实验中心完成。①实验分组:30只新西兰白兔随机分为正常对照组、术后2d减压组、术后7d减压组、术后14d减压组、术后不减压组,每组6只。②造模:除正常对照组外,其余各组在视神经孔中塞入一细端为2mm直径的圆锥软硅胶,阻塞视神经孔,造成视神经的挤压伤。③指标检测:采用图形翻转视觉诱发电位检测损伤前、损伤后1h、减压前1h、减压后2周视功能变化,记录NPN曲线主波(P波)的绝对潜伏期、绝对波幅。正常对照组仅采集一组数据作为对照。结果:30只实验动物均进入结果分析。①正常对照组家兔图形翻转视觉诱发电位检查均引出典型NPN波型曲线,视神经挤压伤后1hNPN波形低阔扁平,P波潜伏期延长,波幅降低。②P波潜伏期:术后2d减压组减压后短于减压前[(71.25±8.51),(86.47±14.28)ms,P<0.05];术后7d减压组减压前后比较差异无显著性(P>0.05);术后14d减压组减压后明显长于减压前[(158.73±15.16),(116.35±17.13)ms,P<0.05]。术后2d减压组和术后7d减压组短于术后不减压组(P<0.01)。术后7,14d减压组和术后不减压组明显长于正常对照组(P<0.01)。③P波波幅:术后2d减压组减压后高于减压前[(5.25±0.78),(4.42±0.42)μV,P<0.05]。术后2d减压组减压后低于术后7d减压组、术后14d减压组(P<0.01),术后14d减压组低于术后7d减压组(P<0.05);术后7d减压组、术后14d减压组、术后不减压组低于正常对照组(P<0.01)。结论:神经元继发性损伤是视功能进行性下降的重要原因,视神经减压术有利于减轻视神经间接损伤,较早期(损伤后48h以内)减压可阻止轴突继发性损伤,避免视功能进一步下降,并在一定程度上逆转视功能的损害。     

中国白兔视神经损伤后的闪光视觉诱发电位的实验研究

中国白兔近年来较多的被用于眼科学研究,但目前对其正常的视觉电生理学特性尚不明了,少见文献报道。我们研究了中国白兔的闪光视觉诱发电位(F lash visual evoke potentials,F-VEP),确立其正常值的范围及视神经损伤后的变化特征,旨在为进一步的视神经损伤修复的研究奠定基础。1     

Imaging of the optic nerve and visual pathways

The visual pathway extends from the globes anteriorly to the occipital cortex posteriorly. A wide variety of disease processes may produce visual dysfunction. Because the optic nerve is a fiber tract of the brain covered by meninges, it can be affected by many of the same pathologic processes that occur in the brain and meninges. Physical examination and diagnostic tests of visual function performed by the clinician can frequently identify the anatomic location of the causative lesion in the patient with vision loss. This enables the radiologist to optimize the imaging evaluation of the patient. This article reviews the normal anatomy of the optic nerve and visual pathways, presents computed tomography (CT) and magnetic resonance (MR) imaging techniques for evaluation of these structures, and discusses the pathologic processes intrinsic to the optic nerve and visual pathways.     

Correlation of visual axis and coronal axis measurements of the optic nerve sheath diameter.

OBJECTIVE: There are several approaches to sonographic imaging and measurement of the optic nerve sheath diameter (ONSD). In this study, we sought to compare visual axis measurements of the optic nerve sheath (ONS) with traditional coronal axis measurements to assess for correlation. METHODS: The ONS was visualized in 2 views on both eyes of healthy volunteers using an 8.5-MHz probe. Coronal axis views were obtained with the probe placed at the lateral canthus directed nasally posterior to the globe. Subsequent imaging was made along the midline visual axis. The diameter in this view was measured at several points posterior to the sclera (2, 3, 6, 9, 12, and 15 mm). RESULTS: Twenty-seven subjects were enrolled (54 scans). There was a significant difference between ONSDs measured in each axis, with a coronal axis mean diameter of 3.4 mm and visual axis mean diameters at 2, 3, 6, 9, 12, and 15 mm of 4.28, 4.32, 5.15, 5.74, 6.39, and 7.42 mm, respectively (P < .05). The Pearson coefficient showed no correlation between coronal axis and visual axis measurements, with R values ranging from 0.51 to 0.69. There was a statistically significant increase in the ONSD as the nerve coursed posteriorly when measured in the visual axis. CONCLUSIONS: Visual axis measurements do not reliably correlate with coronal axis measurements. The consistently larger diameter measured in the visual axis as well as the gradually increasing diameter posteriorly suggests measurement of an artifactual shadow rather than the true ONS.     

视神经减压术对颅脑损伤合并视神经损伤视力康复的意义

Therewasmuchcontroversyovertheeffectofsurgicaltreatmentonopticneuropathyduetoheadtrauma．From１９９５～２００１，wecomparedtheeffectofdecompressionofopticnerveandconservativetreatmentonopticneuropathyfollowingheadtraumareceivedin１６patients．Therapeuticeffectofdecompressionissatisfying，hereisthereport．１Subjectandmethod１．１Subject１６patientsincluded１４menand２womenagedbetween１６～４５yearsoldwithmeanageof２９．５years．Allheadtraumaswerecausedbytrafficaccident．５casessufferedfromuni…     

肌骨超声诊断肢体肌腱和韧带损伤进展

随着超声技术的发展,图像质量及分辨率不断的提高,适应范围不断扩大,也逐渐开始应用于肌肉骨骼系统的诊断中.肢体肌腱和韧带属于人体肌肉收缩及关节稳定的重要组织,一旦出现损伤不及时治疗,将会对患者的功能造成障碍,因此积极研究早期诊断技术对于临床治疗有着重要意义.肌骨超声作为近年来新兴诊断技术已经得到越来越多的关注,如何应用肌...