人工晶状体的材料设计与视觉质量

目前白内障摘出术后的人工晶状体眼视力可以恢复到接近正常。眩光、光晕、暗视力差、客观视力好而主观视物模糊等视觉质量问题与人工晶状体制作材料、构型设计等相关。选用恰当的人工晶状体可以减少术后散光、后发性白内障,并保持一定的调节力。     

共同性外斜视各类型分布的临床观察

目的了解共同性外斜视各种类型分布的情况。设计回顾性病例系列。研究对象共同性外斜视患者1161例。方法对1161例欲行斜视矫正术的共同性外斜视患者的斜视类型、视力及斜视度进行统计和分析。主要指标共同性外斜视的类型,视力与矫正视力,斜视度等。结果1161例共同性外斜视患者中,间歇性外斜视470例(40．48％),恒定性外斜视258例(22．22％),知觉性外斜视166例(14．30％),残余性外斜视38例(3．27％),连续性外斜视2例(0．17％),共同性外斜视伴垂直斜视227例(19．55％)：先天性外斜视2例(0．17％)。斜视度＞60~Δ者中间歇性外斜视175例(37．24％),恒定性外斜视199例(77．55％)。共同性外斜视除外知觉性外斜视,视力或矫正视力≥1．0者945例(94．97％)。共同性外斜视近视性屈光不正者519例(85．36％)。结论在共同性外斜视中,间歇性外斜视占首位。恒定性外斜视斜视度显著大于间歇性外斜视。共同性外斜视患者的视力与矫正视力绝大多数是正常的。共同性外斜视的屈光状态主要是近视性屈光不正。(眼科,2006,15：331-334)     

Retinal projections to the pregeniculate nucleus in the hemispherectomized monkey

Intraocular injections of tritiated proline were used to test the hypothesis that unilateral removal of all visual cortical areas results in increased distribution of retinal terminals in the pregeniculate nucleus (PGN) of the thalamus in monkeys. Following hemispherectomy, retinal input to the ipsilateral PGN was reduced by an average of 18.5% when compared to its contralateral homologue, which corresponded to the reduction in nuclear volume (19.3%). Our results show that removal of cortical afferents to the external layer of the PGN does not induce invasion of retinal projections into this region of the nucleus.     

运动所致血浆K+和血pH值的变化对肌肉疲劳和表面肌电图的影响

目的探讨血K+、H+与肌肉疲劳和肌电变化的关系.方法对同一批受试者在200 W和120 W蹬功率车之前和运动至疲劳后即刻、5 min、10 min、20 min时,测定血浆K+、血pH值以及活动肌和非活动肌定量负荷等长收缩10 s的肌电图(EMG).结果两次运动后血浆K+和活动肌平均功率频率(AM-MPF)均明显改变(P<0.01),二者高度负相关,并在20 min时基本恢复.200 W运动后20 min内血pH值一直明显低于安静值(P<0.01),但在120 W运动后无变化,并与肌电无相关关系.120 W运动后20 min内的非活动肌积分肌电图值(IM-IEMG)明显低于安静值(P<0.05).结论细胞外高K+是肌肉疲劳和AM-MPF下降的主要因素之一,并可能也是IM-IEMG下降的原因之一.H+不是疲劳形成的主因,并对肌电无直接影响.     

人工视觉的最新进展

主要就目前国内外人工视觉技术的最新进展进行叙述,并对其发展前景和国内发展的可行性做简单讨论。     

慢性疲劳综合征的胃肠道症状和对胃排空影响的调查

目的调查慢性疲劳综合征(CFS)患者胃肠道症状的发生情况与胃排空功能的相关性。方法采用问卷调查43例CFS患者胃肠道症状的发生情况并对胃部症状进行评分,通过同位素测定其液相和固相胃排空功能,与38例健康对照者比较。结果CFS患者胃肠道症状的发生率较健康对照组显著升高。胃部症状评分与固相(r=0.81)和液相(r=0.65)胃排空减慢显著相关(P<0.001)。结论CFS患者的胃部症状与胃动力异常有关。     

影响白内障术后人工晶状体眼视觉质量的因素分析

提高白内障的手术质量,使患者不仅脱盲、脱残,而且能达到理想的视觉质量是白内障复明工作所面临的新的挑战.除了手术设备和手术操作,人工晶状体的材料、设计及功能是决定人工晶状体眼视觉质量的关键所在.评价人工晶状体眼视觉质量不仅包括视力检查,而且需结合对比敏感度、眩光和像差等一系列综合评价指标.为了同时获得较好的远、近视力,植入多焦点人工晶状体是一种有效的方法.     

建立闭路式强化优先注视法检测系统的初探

目的建立由电脑控制的闭路式强化优先注视法视力检测系统(Closed-circuitOperantPreferentialLookingSystem,COPL),并探讨其临床的实用性。方法装置:本系统由刺激显示部分和眼动监视部分组成。刺激显示部分含动画图像强化幼儿注视条栅的行为,眼动监视部分可观察到幼儿的注视行为。测试过程由电脑控制。对象:随机选择符合录入标准的幼儿79人(男42人,女37人)作为研究对象,年龄12～40月,平均23.81±8.38月,按年龄分为7组。结果可测性:完成视力检查的幼儿66人,男35人,女31人,总可测性为83.54%,男可测性为83.33%,女可测性为83.78%。测试时间:统计完成视力检查的幼儿的平均测试时间329.70±86.60秒。视力情况(以折合5分记录表示):(1)视力与性别的关系:采用独立样本t检验比较男女视力,差异无显著性(=0.41)。(2)各年龄组的平均视力:12～16月组4.47±0.12,17～20月组4.58±0.17,P21～24月组4.60±0.21,25～28月组4.79±0.19,29～32月组4.81±0.16,33～36月组4.88±0.18,37～40月组5.0±0.00。(3)视力与年龄的关系:12～40月幼儿的视力发育与年龄呈高度正相关(相关系数r=0.76,P=0.00),进一步推出视力(Y)与月龄(X)之间的回归直线为:Y=0.0208X+4.1872。(4)重复性:20名幼儿完成两次视力检查,且两次皆由一位检查者操作     

Visual experience during cataract surgery: a nation-wide survey on the knowledge of optometry students.

PURPOSE: Many patients experience a variety of visual sensations during cataract surgery under local anaesthesia. Up to 16.2% of patients are frightened by their intraoperative visual experience. This study aimed to determine the knowledge and beliefs of optometry students on this subject. METHODS: A nationwide survey using a standardised, self-administered questionnaire was conducted on all optometry students in Singapore. RESULTS: For cataract surgery under regional anaesthesia, 38.9% of the respondents believed that patients might experience no light perception while 68.5% felt that patients were likely to be able to perceive light. Overall, 70.4% felt that patients might be frightened by their visual experiences and 88.0% believed that preoperative counselling of patients would serve to reduce the fear experienced during the surgery. For cataract surgery under topical anaesthesia, 37.0% of the respondents believed that patients would perceive no light and 74.1% believed that patients would retain light perception. Overall, 67.6% believed that patients may be frightened and 86.1% felt that preoperative counselling would help. CONCLUSION: Many optometry students correctly believed that patients might experience a variety of visual sensations during cataract surgery under local anaesthesia. The majority were also aware that patients might be frightened by this and felt that preoperative counselling would be helpful.     

图形视诱发电位对甲状腺相关眼病视神经病变的诊断价值

目的　评价图形视诱发电位(P -VEP)在甲状腺相关眼病视神经病变(DON)中的诊断价值及其影响因素。方法　对2 0 0 2年1月至2 0 0 3年12月收治的99例(188眼)TAO患者行常规P -VEP检查,比较矫正视力≥1. 0患眼与正常值之间以及矫正视力≥1 .0与<1. 0TAO患者之间P10. 0潜伏期及振幅变化;观察眶压、眼压及眼球突出对P10 .0潜伏期的影响;比较P -VEP与视野检查在DON中的诊断价值。结果　矫正视力≥1. 0组P10 .0平均潜伏期及振幅较正常值均有明显差异;视力≥1 .0组与<1 .0组比较,后者P10. 0潜伏期在中、高空间频率明显较前者延迟;眶压对P10. 0潜伏期影响最大;P -VEP较视野检查更灵敏,两者联合阳性率可达93 97%。结论　P -VEP视功能检查可以更敏感的较早发现DON的发生,并且可在一定程度上判断视神经的损伤程度;眶压在DON发生、发展中起关键性作用;P -VEP与视野检查联合应用可明显提高DON的诊断阳性率,是诊断DON较为灵敏和可靠的方法