Corneal toxic changes after cataract extraction

Over an 18-month period 10 patients (12 eyes) presented with severe corneal toxic changes after cataract extraction. Defined stages in the keratopathy included punctate epithelial keratopathy, pseudodendrite, central epithelial ulcer and central stromal ulcer. Periods of up to 13 months were required for resolution of the defects. Axial scarring and nonhealing epithelial defects resulted in a final visual acuity of counting fingers and hand movement in two patients. We believe that exposure during the postoperative period to benzalkonium chloride contained in ophthalmic medications represents the most likely cause of the toxic changes and that no single ophthalmic medication can be held responsible. The past ocular histories of the patients included chronic open-angle glaucoma, dry eye syndrome and anterior membrane dystrophy. Prior exposure to benzalkonium-containing antiglaucoma medications, tear film deficiencies or abnormalities of epithelial adhesion may have predisposed the corneas in these patients to the development of benzalkonium-related toxic changes.     

Keratometric changes after cataract extraction.

One hundred cases of uncomplicated cataract with clear corneae had cataract extraction and were examined at 20 days and six weeks after operation. Keratometry was done preoperatively and keratometry and retinoscopy at each of the follow-up visits. The study was undertaken to evaluate the type (whether pre- or postplaced) and the number of sutures (one, three, or five) that produce the least postoperative astigmatism. We found that the type of suture was immaterial but that three sutures produced the least astigmatism.     

Visual rehabilitation of adult patients after unilateral cataract extraction

The influence of correcting soft contact lenses and pleoptic-orthoptic exercises on the improvement of the visual acuity and acquiring of binocular vision was analyzed in 22 patients aged 17-65 years after unilateral cataract extraction. Visual acuity of between 5/5 and 5/16 was attained in 88.6 p.c. of patients, binocular vision in 85.9 p.c. Poorer results were observed in persons with a diminished transparency of the ocular media caused by injury as well as in younger individuals after congenital cataract surgery.     

Visual outcome and complications after cataract extraction in Saudi Arabia.

Cataract is the leading cause of blindness in Saudi Arabia. The author studied 1383 patients who had undergone cataract extraction (total of 1520 procedures) from October 1985 to March 1986 at the King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. All patients were observed for at least two months. Of 1520 eyes 555 (37%) achieved a visual acuity of 20/40 or better, 309 (20%) a visual acuity of 20/50-20/60 after surgery, and 656 (43%) eyes a visual acuity of 20/70 or less. The number of eyes that had intraoperative complications was 176 (12%). The number of eyes that had postoperative complications was 539 (35%). Some eyes had more than one complication. The main factors responsible for failure to achieve visual acuity of 20/40 or better were: (1) error of refraction in 492 (32%) eyes; (2) pre-existing corneal scarring and opacity in 211 (14%) eyes; (3) climatic droplet keratopathy in 134 (9%); and (4) presumed visual loss due to glaucoma in 134 (9%) eyes.     

儿童先天性白内障术后视觉发育观察

目的评价儿童先天性白内障摘除及人工晶状体光学部后囊夹持植入术后联合视功能训练的疗效。方法将连续收集73例(129只眼)3~6岁的儿童分为三组,治疗组31例(50只眼)为先天性白内障组,均行白内障摘除联合人工晶状体光学部后囊夹持植入术,术后行弱视治疗;对照组1共23例(41只眼)为屈光不正性弱视儿童;对照组2共19例(38只眼)为视觉发育正常儿童。三组治疗前后或观察前后均进行最佳矫正远视力(BCDVA)、屈光度、视觉诱发电位(VEP)、光学相干断层成像(OCT)及同视机的检查。随访期为6~24个月。结果(1)先天性白内障术后BCDVA明显高于术前BCDVA,差异具有统计学意义(P<0.05)。(2)双眼白内障术后视功能与单眼白内障术后视功能差异无统计学意义(P>0.05)。(3)治疗组与对照组1的VEP中P100的振幅和潜伏期差异无统计学意义(P>0.05),但两组与对照组2的VEP中P100的振幅和潜伏期比较差异有统计学意义(P<0.05)。(4)先天性白内障术后视觉高级功能恢复为I级视功能6例(19.35%),同时具有I和II级视功能2例(6.45%),同时具有I、II和III级视功能10例(32.25%),无视觉功能13例(41.94%)。双眼和单眼白内障在视功能的恢复上差异无统计学意义(P>0.05)。(5)先天性白内障术后检测黄斑厚度分别与两对照组比较差异无统计学意义(P>0.05)。(6)随访期间白内障手术组均未见后囊混浊发生。结论先天性白内障儿童行白内障摘除联合人工晶状体光学部后囊夹持植入术后积极治疗弱视,可促进视觉发育,使儿童获得满意的视功能。     

Densitometric analysis of changes in the vitreous body after cataract extraction

Densitometric methods for analyzing the images obtained at biomicroscopy were used to study the transparency of the spatium retrolentalis, membrana hialoidea anterior, and pars retrolenticularis of the vitreous body of 45 eyes after cataract phacoemulsification. In half the patients, the optical density in these structures has shown to increase as compared with the normal values, which is mainly associated with the opacity of the vitreous body and the increased destruction of its tracts. The results of drug treatment and a role of additional therapy with plasmin and collagenase activators in the complete rehabilitation of patients after surgical cataract treatment are discussed.     

Visual field changes after laser in situ keratomileusis

PURPOSE: To determine whether laser in situ keratomileusis (LASIK) affects the central 30-degree visual field. SETTING: University-based ophthalmology practice. METHODS: This nonrandomized clinical trial comprised 14 normal patients (27 eyes) scheduled to have LASIK for myopia or myopic astigmatism. Automated static perimetry was performed before and 6 months after surgery using the Octopus 1-2-3 perimeter and the Dynamic-32 test strategy. Patient data included sex, age, preoperative and postoperative refractive errors, preoperative and postoperative best corrected visual acuity, preoperative corneal thickness, programmed optical zone, programmed total ablation diameter, and duration of microkeratome suction. All surgery was performed using the same Alcon LADARVision 4000 excimer laser. The main outcome measures were the mean sensitivity (MS) change in the central 15-degree visual field and the MS change in the 15- to 30-degree visual field. A multivariate analysis of the MS change as a function of preoperative clinical parameters was performed. RESULTS: There was no significant change in the MS in the central 15-degree visual field; between 15 and 30 degrees, there was a statistically significant decrease of -0.82 dB +/- 1.40 (SD) (P=.01, 2-tailed t test). The decline in MS was positively correlated with refractive error and corneal thickness; it was negatively correlated with the programmed optical zone diameter. CONCLUSIONS: Automatic static perimetry can detect decreased sensitivity in the midperipheral visual field after myopic LASIK. It may be a useful quantitative subjective test for measuring the effects of future improvements in surgical technique on vision quality.     

白内障术后房水一氧化氮及一氧化氮合酶的动态变化

目的：探讨白内障术后房水一氧化氮（NO）与炎症反应的关系。方法：用新西兰白兔动态观察对照组、晶状体囊外摘出术组（ECCE）和晶状体囊外摘出＋人工晶状体植入术组（ECCE＋IOL）眼内炎症反应及房水一氧化氮合酶（NOS）和NO2－／NO3－的活性。结果：白内障术反应与房水NOS和NO活性呈动态变化,ECCE＋IOL组明显高于ECCE组,且上两组均高于对照组。结论：房水NO的变化与白内障术后眼内炎症反应密切相关。     

近视患者准分子激光上皮瓣下角膜磨镶术后视野的改变

目的:探讨准分子激光上皮瓣下角膜磨镶术对中高度近视及散光患者30°中心视野的影响。方法:将实施LASEK的近视及散光患者分为中度近视组和高度近视组:Ⅰ组28眼,近视-2.50~-6.00DS;Ⅱ组100眼,近视-6.25~-14.00DS。术前、术后1wk,6mo使用Oc-topus1-2-3视野计行自动静态视野检查。观察指标包括0°~15°中心视野平均敏感度(mean sensitivity,MS)和15°~30°中心视野平均敏感度。以术后1wk,术后6mo与术前平均敏感度差值(△MS)进行配伍组设计的两因素方差分析,差异有统计学意义时用SNK法行两两比较。结果:术后1wk患者裸眼视力均达到0.8以上者分别为78%和39.0%,6mo后视力在0.8以上者分别为93%和56.0%。Ⅰ组:术后1wk0°~15°中心视野MS改变无显著性,15°~30°中心视野MS有所下降;术后6mo0°~15°及15°~30°中心视野△MS均无显著差异。Ⅱ组:术后1wk0°~15°及15°~30°中心视野MS均有下降;术后6mo0°~15°中心视野△MS仍具有统计学意义,15°~30°中心视野△MS无显著差异。结论:自动静态视野检查可检出高度近视患者LASEK术后0°~15°中心视野视野改变,术后6mo虽有回升趋势,但仍低于术前水平。因此,本研究认为近视尤其是高度近视患者进行视野检查,对屈光性角膜手术的筛选非常重要。     

小切口白内障囊外摘出联合人工晶状体植入术后眼前节变化分析

目的探讨小切口白内障囊外摘出联合人工晶状体植入术后患者眼前节的变化。方法对104例(104眼)老年性白内障患者施行小切口囊外摘出联合人工晶状体植入术,对手术前后患者的眼压、前房深度、角膜屈光力(K值)、前房角进行对比观察。结果术后1个月时眼压为(12.96±1.87)mmHg(1kPa=7.5mmHg),较术前(13.61±1.56)mmHg有所下降,但差异无统计学意义(t=0.396,P>0.05)。术前前房深度为(2.98±0.39)mm,术后为(4.16±0.56)mm,差异有显著统计学意义(t=5.431,P<0.01)。术后K值较术前有所增加,但差异无统计学意义(t=0.461,P>0.05)。术后前房角镜检查均可见小梁功能区,术前、术后前房角情况分类比较,差异有显著统计学意义(χ2=42.16,P<0.01)。结论小切口白内障手术有效地改善了患者前房角宽度及前房深度。     

Visual outcome following complicated extracapsular cataract extraction.

In a prospective study of 1,597 consecutive extracapsular cataract extractions (ECCE), we review 49 cases complicated by capsular or zonular rupture with or without vitreous loss. The ECCEs were divided into two groups depending on the type of intraocular lens (IOL) implanted. In Group A, whose patients received an anterior chamber lens, we found a significantly (P < .05, t-test) worse postoperative visual acuity than in Group B whose patients received a posterior chamber lens. We therefore suggest that in the presence of a capsular tear and vitreous loss, one should try to implant a posterior chamber lens rather than an anterior chamber lens to obtain as good a visual acuity as possible.     

Personal experience with modern extracapsular cataract extraction

In the group of 42 eyes with extracapsular cataract extraction the postoperative results were very favourable differing conditions. There did not occur any more serious postoperative complications. Authors verified that for a skillful ophthalmic surgeon this operation is easily performed, on the other hand many of them have to overcome some accustomed aversion and to use at present time the needed extracapsular extraction, in spite of the previous routinely used intracapsular technique, which was successfully performed for many years. Present trend of extracapsular cataract extractions is based on the aim to decrease the number of the postoperative complications and to make possible the implantation of the intraocular lenses into the posterior chamber of the eye.