儿童白内障术后远期结果的研究进展

本文对近几年一些学者对儿童白内障远期随访结果进行了综述和评价。手术时机选择、儿童特殊的屈光变化以及如何精确测定儿童植入人工晶状体性能及屈光度都对儿童白内障术后远期视功能产生影响。慢性青光眼是儿童白内障术后远期丧失视力的主要原因。长期弱视治疗是获得手术成功的保证之一。因此，要真正获得有用的视功能，应重视儿童白内障手术后的后续治疗，并提议应建立完善的白内障术后追踪随访和弱视治疗机构。     

虹膜夹型有晶状体眼人工晶状体植入术对高度近视眼对比敏感度的影响

目的 研究虹膜夹型有晶状体眼人工晶状体（iris-claw phakic intraocular lens，ICPIOL）植人术后对比敏感度（contrastsensitivity，CS）的变化。方法 2005年5月至12月于温州医学院附属眼视光医院和中山大学中山眼科中心接受ICPIOL（Verisyse，美国AMO公司）植入术的高度近视眼患者12例（23只眼），分别在术前、术后1、3、6个月采用CS测试灯箱（CSV-1000型，美国Vector Vision公司）检查暗视状态下无／有眩光时的对比敏感度函数（contrast sensitivity function，CSF）。结果 术后1、3、6个月等效球镜度数分别为（-0．60±0．77）D，（-0．48±0．77）D，（-0．34±0．53）D，与术前（-15．53D±3．65D）差异均有显著统计学意义（P均〈0．001），最佳矫正视力（IogMAR）分别为0．064-0．12，0．02±0．09，-0．003±0．08，与术前（0．21±0．12）差异均有显著统计学意义（P均〈0．001）。术后各空间频率的CS与术前比较有增高趋势。术后3个月6、12、18周／度的CS在无眩光时和有眩光时均明显提高（P均〈0．01），开始接近正常范围。术后3、6个月在各空间频率上CS差异均无统计学意义（P均〉0．05）。结论 ICPIOL植入术矫治高度近视眼可以使CSF恢复到接近正常范围，显著改善视功能，是一种适用于高度乃至超高度近视眼的可供选择的屈光手术。     

聚甲基丙烯酸羟乙酯水凝胶人工晶状体材料的合成与性能

以甲基丙烯酸羟乙酯为原料,过硫酸铵/偏重亚硫酸钠为引发体系,二甲基丙烯酸三乙二醇酯为交联剂,采用溶液聚合法制备了聚甲基丙烯酸羟乙酯水凝胶(PHEMA)人工晶状体材料。系统考察了聚合反应时间、温度及引发剂和交联剂的用量等对该水凝胶材料机械强度、平衡水含量(EWC)的影响,并对PHEMA水凝胶的结构和光学性能进行了表征。实验结果表明,PHEMA水凝胶的最佳合成条件为:引发剂0.5wt%,交联剂1.0wt%,反应温度40℃,反应时间36h。在此条件下制备的PHEMA水凝胶的拉伸强度达到0.57MPa,邵氏A硬度为23.0,平衡含水量超过40%,透光率≥97%。     

白内障晶状体上皮细胞及晶状体纤维超微结构的观察

应用胎儿晶状体发育的超微结构为形态学依据,观察老年性、外伤性、先天性白内障晶状体的超微结构.结果:老年性白内障晶状体上皮多数细胞膜破裂,作者首先发现其原因是相邻细胞顶部的紧密连结缺失,房水侵入所致.胞质中线粒体空泡化,内质网扩张、脱粒.晶状体纤维膨胀、崩溃.细胞之间的各种连结消失.外伤性白内障除具有白内障特点外,胞质中出现大量溶酶体、残体.1例先天性白内障,上皮细胞发育尚好,晶体纤维不发育.     

Self-Regulated Facial Muscle Tension Effects on Intraocular Pressure

This study was designed to examine the relationship between orbicularis muscle tension around the eyes and fluctuations in intraocular pressure (IOP) in normal subjects. Using a biofeedback paradigm, 20 male and female subjects were asked to increase and decrease their EMG activity from the orbicularis muscle while receiving EMG feedback. Subjects received 3 alternating blocks of trials in which they attempted to increase and decrease muscle tension while maintaining the eyes open. A fourth trial consisted of a forceful closure of the eyes during the increase period. IOP was measured every 60 s throughout the entire sequence, and electrodes placed above and below the eye recorded eyeblinks. Results suggest that IOP increases with increases in facial muscle tension in normal subjects, a finding which cannot be accounted for by changes in eyeblink frequency. These results imply that increases in IOP occur during periods of increased muscle tension around the eye and suggest that muscle tension levels should be examined among individuals who have abnormally high IOP levels.     

Diagnosis of retinoblastoma by fine-needle aspiration and aqueous cytology

This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit.     

人工晶体植入前后视觉诱发电位的临床分析

目的:(1)探讨白内障囊外摘除术前术后及人工晶体植入术后视觉诱发电位幅值及潜时变化特征;(2)探讨白内障囊外摘除术术前P—VEP,F—VEP,F—ERG联合预测的必要性。方法:采用重庆泰克医电仪器公司产TEC—100C视觉电生理仪。对白内障患者实行分组测量。术前均测F—ERG,P—VEP,部分病例增测F—VEP。结果:114例术前F—ERG正常,P—VEP测量其P_(100)波幅值潜时均异常:P_(100)波幅值降低,潜时延长,术后及人工晶体植入后幅值,潜时都有所改善,而并发性白内障,代谢性白内障变化不明显。结论:据视觉诱发电位的变化,老年性白内障组,外伤性白内障组术后应及时装入人工晶体,并发性白内障组,代谢性白内障组装入人工晶体临床意义不大。术前联合测试(VEP ERG)对视力预后、以及眼底病变的定量诊断意义重大。     

Ectopia lentis in Loeys‐Dietz syndrome type 4

Loeys‐Dietz syndrome is a heritable disorder of the connective tissue leading to multisystem involvement including craniofacial features, skeletal abnormalities, cutaneous findings and early‐onset and aggressive disease of the aorta and its branches. There are multiple types of Loeys‐Dietz syndrome related to pathogenic variants in TGFBR1, TGFBR2, SMAD3, TGFB2, and TGFB3. Individuals with Loeys‐Dietz syndrome may be misdiagnosed as having Marfan syndrome due to shared phenotypic features and aortic root dilation. However, ectopia lentis has been an important discriminating feature, being unique to Marfan syndrome and not reported to be associated with Loeys‐Dietz syndrome. We report the case of a 46‐year‐old woman with Loeys‐Dietz syndrome type 4 due to a pathogenic variant in TGFB2 who was diagnosed with ectopia lentis at age 44. The patient underwent whole exome sequencing and no other pathogenic variants were found to explain the ectopia lentis. Our findings indicate that ectopia lentis may be an uncommon finding in Loeys‐Dietz syndrome type 4 and emphasize the importance of genetic testing in familial thoracic aortic aneurysm disease.     

Specular microscopy of hard contact lens wearers

Wide-field specular microscopy, slit-lamp examination, and pachometry were performed on 22 successful hard contact lens wearers and 22 controls matched for age, race, sex, and refractive error. A minimum of 600 cells per control and 1200 per contact lens wearer were manually digitized from the specular photomicrographs. Frequency distributions of cell areas were compared between the two groups using the parameters of mean, median, standard deviation, coefficient of variation, skewness and kurtosis. Slit-lamp examination was normal and there was no significant difference in corneal thickness between the patient group and the control group. Comparison of mean, median, and standard deviation also revealed no significant difference, but skewness (P less than .001), kurtosis (P less than .001) and coefficient of variation (P less than .004) were greater in the hard contact lens wear group. Hard contact lens wearing time correlated with increasing pleomorphism (P less than .05). Specular microscopy also revealed morphologic changes including deep stromal striae, intra- and extracellular "blackout" areas, and clustering of extremely small and large cells. The possible relationship between endothelial hypoxia and structural stromal changes are discussed.