视神经管的CT扫描技术

目的探讨视神经管的CT扫描方式及影像表现。方法分别对体外神经管模型和8例疑有神经管损伤的患者进行视神经管的轴位和冠状位扫描。结果在轴位图像上,视神经管呈轨道状;在冠状位图像上,视神经管呈“蝶眼状”。结论CT轴位 冠状位扫描,可清楚显示视神经管大小、形状及邻近结构,故在临床上有一定的应用价值。     

Visually guided reaching: bilateral posterior parietal lesions cause a switch from fast visuomotor to slow cognitive control

The visually guided reaching of two patients with bilateral optic ataxia was explored in two experiments. In Experiment 1 simple delayed pointing was compared with immediate pointing. In the immediate pointing task both variable and constant errors increased with target eccentricity. In contrast to the performance of control subjects and contrary to their own beliefs, the patients both showed improved accuracy in the delay condition. This improvement was manifest as a reduction in both pointing variability and in the constant angular error towards the point of fixation. Both angular errors and their improvement with the delay were proportional to target eccentricity. Experiment 2 used a task in which the target was pre-viewed 5s prior to its re-exposure for pointing ('delayed real pointing'). On some trials a conflict was introduced between the present and previous visual information by changing the target's location during the delay. In contrast to control subjects, who ignored the pre-viewed location and aimed directly at the current target, both patients with optic ataxia initiated their movements towards the previously viewed target location. Evidently they relied on off-line information in preference to on-line visual information. In addition, the patients often failed to detect the changes in target location. One of the patients sometimes even guessed incorrectly that the target had changed its location, and her movement trajectory was then more affected by her false belief than by the target's actual location. These findings confirm that posterior parietal lesions severely disrupt direct visuomotor transformations, and suggest that the residual performance is mediated indirectly by expectations or beliefs about target position.     

翼点入路显微手术切除视交叉前置型巨型垂体腺瘤

部分巨大的垂体腺瘤向后上方浸袭第三脑室前部，向前推移视交叉致使视交叉前间隙（间隙1）狭小，以及部分病人先天前置视交叉的存在，术中很难通过视交叉和鞍结节之间显露肿瘤，加之肿瘤向鞍后，     

垂体腺瘤对视功能损害的临床观察

目的：探讨垂体腺瘤对眼视功能损害的临床表现。方法：对126例（252只眼）垂体腺瘤患者进行视力、视野、荧光眼底血管造影（Fundusfluoresceinangiography，FFA）、图形视诱发电位（Patternvisualevokedpotential，PVEP）及眼底检查。结果：视力下降186只眼，占73．8％。眼底原发性视神经萎缩130只眼，占51．6％。视野缺损156只眼，占69．6％。PVEP异常160只眼，占88．9％。26．2％的患者以眼部异常为首诊症状．其中16．7％曾被诊断为眼科疾病。结论：垂体腺瘤可引起视功能的损害，充分认识垂体腺瘤在眼部的临床特点，有助于早期诊断及时治疗。     

Structure–function relationship in ocular hypertension and glaucoma: interindividual and interocular analysis by OCT and pattern ERG

BACKGROUND: Pattern electroretinogram (PERG) and optical coherence tomography (OCT) represent objective probes to investigate respectively the function of retinal ganglion cells and their structure as retinal nerve fiber layer (RNFL) thickness. We examined interindividual (II) correlations of PERG amplitude and RNFL thickness, as well as correlations between interocular (IO) differences in both measures, in ocular hypertension (OHT) and early glaucoma (EG) patients. METHODS: Thirty-one OHT, 34 EG (mean deviation: -1 to -6 dB) and 16 age-matched controls were examined in both eyes. Participants had clear optical media, no or moderate refractive errors and no concomitant ocular or systemic diseases. PERGs were elicited by counterphased (16.28 reversals/second) gratings (1.6 cycles/degree spatial frequency). The Fourier isolated 2nd harmonic PERG amplitude and phase were measured. RNFL thickness was quantified by means of OCT Stratus according to a standard protocol. Average, superior and inferior RNFL thicknesses were considered. RESULTS: Mean PERG amplitude was decreased (p < 0.01) in both OHT and EG patients compared to controls. Mean RNFL thicknesses were reduced (p < 0.01) in EG patients compared to both OHT and controls. In OHT patients, PERG amplitude did not correlate significantly with RNFL thickness in both II and IO analysis. In EG patients, PERG amplitude was positively correlated with RNFL thickness in both II (p < 0.005) and IO (p < 0.001) analysis. The slope of the correlation predicted that PERG losses exceeded systematically RNFL losses when the latter were between 0 and -0.25 log units. CONCLUSIONS: Both II and IO analyses revealed a lack of structure-function relationship in OHT, suggesting that, at this disease stage, PERG losses appear to affect primarily retinal/optic nerve head function. In EG they reflect both dysfunction and RNFL loss.     

视乳头结构即时测量新法——+78D前置镜合并目镜刻度尺法

目的：探讨＋78D前置镜合并目镜刻度尺测量法作为新的视乳头结构即时测量方法的测量一致性，并和直接眼底镜进行测量一致性比较。 方法：两名检查者分别使用直接检眼镜和＋78D前置镜合并目镜刻度尺法对所有受检眼（477眼）测量视神经垂直杯盘比比值，计算仪器间的测量可重复性。对前100只眼，两名测量者均采用＋78D前置镜合并目镜刻度尺法测量垂直杯盘比、视盘直径和视杯直径，均采用直接检眼镜测量垂直杯盘比，计算同一测量仪器的检查者问可重复性。 结果：本研究受检者有257名（477眼）。两名检查者利用＋78D前置镜合并目镜刻度尺法测量视盘直径、视杯直径和垂直杯盘比得出95％一致性区间分别为-43～＋4．5、-7．2～＋6．2和-2．2～＋2．8，没有成比例偏倚，而直接检眼镜的95％-致性区间为-0．33～＋0．38。两种测量方法进行比较发现直接眼底镜倾向于高估垂直杯盘比值，没有成比例偏倚。 结论：＋78D前置镜合并目镜刻度尺测量垂直杯盘比的检查者间一致性测量结果较好，测量值变异比直接检眼镜小，并且直接眼底镜倾向于高估垂直杯盘比值。建议＋78D前置镜合并目镜刻度尺用于临床检查即时判断以及基层和社区青光眼筛查。     

Plasma endothelin-1 levels depress optic nerve head circulation detected during the glucose tolerance test

Purpose To determine the relationship between the changes in optic nerve head (ONH) circulation and the level of plasma endothelin-1 (ET-1) during the glucose tolerance test (GTT). Methods Twenty-six healthy volunteers with normal GTT and 15 patients with mild hyperglycemia and abnormal GTT were studied. The ONH circulation [square blur rate (SBR) value], blood pressure, intraocular pressure (IOP), blood glucose, blood insulin and plasma ET-1 were determined before and every hour up to 3 h after an oral intake of 75 g of glucose. Results The SBR increased in the normal glucose tolerance group at all times during the GTT, but it decreased significantly in the abnormal glucose tolerance group (P < 0.05). Before the GTT, the plasma ET-1 level was not significantly different in the two groups; however, the level increased 1 h after the oral GTT in the abnormal glucose tolerance group (P < 0.05). No significant changes were observed in mean blood pressure or IOP. Conclusions ONH circulation increased after glucose intake in the normal glucose tolerance group and remained high even after the blood glucose level had returned to its baseline. The decrease in ONH circulation in the abnormal glucose tolerance group was attributed partly to the increased ET-1.     

复合神经营养因子对大鼠视神经损伤后轴突数的影响

目的观察玻璃体腔注射复合神经营养因子[睫状神经营养因子(CNTF)+脑源性神经营养因子(BDNF)]对大鼠视神经损伤后轴突的形态和纤维数目变化的作用。方法60只雌性健康成年SD大鼠、体重200~225 g,随机分为对照组、CNTF治疗组、BDNF治疗组及复合神经营养因子(CNTF+BDNF)治疗组。各组又分为7、14、21 d 3个时间组,每组5只大鼠,每只动物进行单眼实验,另外一眼为正常对照。四组制成视神经损伤模型后分别向玻璃体腔内注射生理盐水、CNTF、BDNF、CNTF+BDNF。按视神经损伤后不同时间点,分别将动物灌注固定。完整取下视神经,固定,包埋,切片处理后进行图像分析,对正常大鼠视神经内的轴突数和夹伤后大鼠视神经内的轴突数的变化规律进行观察和分析。结果视神经轴突计数结果显示各组轴突数随时间推移逐渐减少。与对照组相比CNTF治疗组、BDNF治疗组及CNTF+BDNF治疗组7、14、21 d各组轴突数均明显多于对照组(P<0.01),且CNTF+BDNF治疗组轴突数亦明显多于单独应用CNTF治疗组、BDNF治疗组(P<0.01)。结论在对大鼠视神经损伤的治疗中,应用CNTF+BDNF明显优于单独应用CNTF或BDNF。     

光动力诱导前部缺血性视神经病变的实验研究

目的 建立大鼠前部缺血性视神经病变（rAION）模型，为缺血性视神经病变的实验研究奠定基础。 方法 通过光动力疗法诱导rAION。30只实验性Sprague-Dawley大鼠随机分为4组，空白对照组5只、激光组5只、光敏剂组5只、光动力模型组15只，右眼为实验眼，左眼为对照眼。光动力模型组从大 鼠 尾静脉注入血卟啉衍生物（HPD）后避光2 h，使用多波长氪离子激光机对大鼠右眼视盘中上 范围进行照射，激光波长647 nm，能量80 mW，照射时间120 s，光斑直径2/3个视盘直径（D D）；激光组使用光动力模型组相同参数的激光持续照射大鼠右眼视盘120 s；光敏剂组单纯 从鼠尾静脉注入HPD；空白对照组未做任何处理。通过眼底、荧光素眼底血管造影（FFA）、 光相干断层扫描（OCT）、视觉诱发电位（VEP）检查及组织病理学检查观察其形态和组织学变化。 结果 3只鼠麻醉意外死亡，共27只鼠进入结果分析。造模后光动力模型组第1~6天眼底检查发现视盘上半水肿，第16天视盘上半边界稍清晰，第23天 视盘上半灰白萎缩边界清晰直至第90天；造模后30 min时FFA检查即可见到大鼠视盘上部强荧光，第1天时FFA检查视盘上部早期弱荧光、中期强荧光；≥16 d时视盘上部始终弱荧光；闪光 VEP 检查 P100潜伏期延长、波幅值降低改变(P＜0.003)；第6天时OCT检查显示视盘视神经反射面高出视网膜反射面，且表面粗糙不平厚度增加，第23天时视盘视神经反射面低于视网膜反射面；组织病理学检查，第1天见视盘部分高度水肿，组织疏松，伴盘周视网膜移位； 第23天见视盘及附近神经纤维层变薄，盘周神经节细胞核数明显减少。激光组、光敏剂组和空白组在不同观 察点和时段未见眼底、FFA、OCT、VEP和组织病理学上的改变。 结论 通过光动力方法诱导建立的拟rAION模型，经眼底、FFA、OCT、视电生理和组 织病理学证实是成功的，并相似于人类的前部缺血性视神经病变。 （中华眼底病杂志，2008，24：90-94）     

复方樟柳碱参与治疗外伤性视神经病变的循证医学评价

目的评价复方樟柳碱参与治疗外伤性视神经病变(TON)的疗效。 方法以“樟柳碱”、“视神经病变”、“外伤”或“挫伤”为关键词，检索2007年4月以前国内生物医学期刊公开发表的有关复方樟柳碱参与治疗TON的临床研究，并对其疗效进行循证医学评价。结果符合纳入标准的对照试验文献6篇，合计415只眼，复方樟柳碱参与治疗后，优势比OR=6.54，95%可信区间为［4.14，10.35 ］，P＜0.00001，差异具有统计学意义；亚组分析P值均＜0.0001。结论复方樟柳碱参与治疗能提高TON的疗效；糖皮质激素治疗联合复方樟柳碱能进一步提高疗效；单纯使用复方樟柳碱治疗TON是可行的。但由于纳入的研究证据强度较低，未来需要更多高质量的多中心、随机、双盲临床试验，以提高该药治疗TON疗效的证据强度。 （中华眼底病杂志，2008，24：103-106）