Similarities and differences between the Kelman phacoemulsification and extracapsular cataract extraction procedures in the spontaneous regression of corneal astigmatism from against-the-rule astigmatism.

We perspectively examined the induction and spontaneous regression of corneal astigmatism from preoperative against-the-rule astigmatism [Kelman phacoemulsification (KPE), n = 618; extracapsular cataract extraction (ECCE), n = 192] among cataract extraction surgeries (KPE, n = 1,648; ECCE, n = 443). All data were set on a double-angle coordinate graph, from which the mean +/- SE of the axis and the amount of astigmatism were obtained simultaneously. In the KPE group, the surgically induced astigmatism was independent of preoperative state or age. In the ECCE group, surgically induced astigmatism shifted toward with-the-rule astigmatism, and postoperative recovery was delayed longer in patients over 80 years of age than in those under 70. Postoperative against-the-rule astigmatism was more frequent after KPE. Our first trial to calculate astigmatism from a double-angle coordinate graph was useful in showing astigmatism changes.     

小切口超声乳化白内障吸除术后角膜散光的变化

目的　探讨小切口超声乳化白内障吸除联合后房型人工晶状体植入手术后角膜散光情况及手术性散光度的变化。方法　对 38例 (38只眼 )白内障患者行上方巩膜倒眉状小切口超声乳化白内障吸除联合人工晶状体植入手术。分别于术前 ,术后 1d、1个月及 3个月使用角膜地形图仪及自动屈光仪进行角膜散光情况检测。结果　平均角膜散光度术后 1d、1个月及 3个月分别为 (1 10± 0 71)、(1 0 8± 0 6 6 )及 (0 87± 0 5 5 )D ;术后 3个月与术前比较差异无显著性 (P >0 0 5 )。平均手术性散光度术后 1d、1个月及 3个月分别为 (1 37± 1 0 3)、(1 2 4± 0 93)及 (1 0 4± 0 75 )D ;术后 3个月与术后 1d比较差异有显著性 (P <0 0 5 )。结论　上方巩膜倒眉状无缝线小切口对术后角膜散光影响小 ;将手术性散光的度数及轴位变化进行矢量分析 ,可综合评价手术致角膜屈光状态的改变 ;角膜地形图可准确反映角膜曲率变化 ,对评价白内障手术后角膜散光变化具有重要的临床意义。     

白内障超声乳化摘出联合人工晶状体植入术后残余散光的研究现状

白内障超声乳化摘出联合人工晶状体（IOL）植入术已成为治疗白内障的主流术式,但存在术后残余散光的问题,影响患者术后裸眼视力的提高.减少术后残余散光已成为目前眼科医师追求的目标.术后残余散光的形成受多方面因素影响,主要与术前即存在的角膜散光和手术源性散光有关.散光型IOL植入术后残余散光除了上述原因之外还有其特殊原因,了解残余散光的形成原因可为减少其形成提供方法.就白内障超声乳化摘出联合IOL植入术后残余散光的原因进行综述.     

Comparison of phacoemulsification and planned extracapsular cataract extraction in combined pars plana vitrectomy and posterior chamber intraocular lens implantation.

BACKGROUND AND OBJECTIVE: To compare two kinds of cataract removal methods combined with pars plana vitrectomy and posterior chamber intraocular lens (PC-IOL) implantation. PATIENTS AND METHODS: Cataract removal was performed by either phacoemulsification or extracapsular cataract extraction (ECCE) and followed by pars plana vitrectomy and PC-IOL implantation. Between May 1996 and June 2001, 31 and 22 patients with cataract and vitreoretinal disease were treated by phacoemulsification and ECCE, respectively, combined with pars plana vitrectomy and PC-IOL implantation. Preoperative demographic data and postoperative vision, astigmatism change, and complications were analyzed. RESULTS: The mean age of patients in the phacoemulsification and ECCE groups was 62.5 and 63.4 years, respectively. Diabetes mellitus was the most common underlying disease resulting in vitreous opacity. Vision improved in 87.1% of the phacoemulsification group and 59.1% of the ECCE group. The change in astigmatism after surgery was 0.92+/-1.08 D (P = .001) in the ECCE group and 0.25+/-0.74 D (P = .087) in the phacoemulsification group. There were fewer postoperative complications, including recurrent vitreous hemorrhage, increased intraocular pressure, and iris changes in the phacoemulsification group than in the ECCE group. CONCLUSION: Phacoemulsification and ECCE combined with pars plana vitrectomy and PC-IOL implantation are both effective surgical methods to achieve better and more rapid visual rehabilitation for patients with combined cataract and vitreoretinal disease. In this study, phacoemulsification combined with pars plana vitrectomy and PC-IOL implantation resulted in greater improvement in vision, less astigmatism change, and fewer postoperative complications.     

两种不同切口人工晶状体植入术后角膜地形图对比分析

目的 研究两种不同切口人工晶状体植入后角膜形态和散光的变化。方法 通过３．２ｍｍ透明角膜切口植入折叠人工晶状体５０眼和６．０ｍｍ巩膜隧道切口植入ＰＭＭＡ人工晶状体４８眼,术后应用计算机辅助角膜地莆图仪对这些病人的角膜形态进行检查。结果 角膜组术后早期角膜地形图垂直于切口径线的角膜轻度变平,于术后１个月即可稳定。巩膜组有膜垂直轴上出殃蝴蝶结样改变,而后蝴蝶结逐渐变小,或向水平方向转变而减少,至３个月时基本稳定。两组在术后１天至１个月的角膜散光和手术性角膜散光巩膜组大于角膜组（Ｐ〈０．０５）。结论 ３．２ｍｍ透明角膜切口组术后角膜形态改变小,视力恢复快。     

Comparison of endothelial cell loss and surgically induced astigmatism following conventional extracapsular cataract surgery, manual small-incision surgery and phacoemulsification

PURPOSE: To compare the surgically induced astigmatism (SIA) and endothelial cell loss following conventional extracapsular cataract surgery (ECCE), manual small-incision cataract surgery (Blumenthal technique)(SICS) and phacoemulsification (PE) with non-foldable intraocular lens implantation. METHODS: 186 cataractous eyes with nuclear sclerosis grade 3 or less were randomized to undergo ECCE, SICS or PE with intraocular lens (non-foldable) implantation after a detailed pre-operative assessment. Keratometry and specular microscopy were performed pre-operatively and 6 weeks postoperatively. Surgically induced astigmatism was calculated using the rectangular coordinate method (Holladay et al.). RESULTS: Mean endothelial cell loss was similar for all three groups (p = 0.855); ECCE induced a loss of 4.72% (SD: 13.07); SICS 4.21% (SD: 10.29) and PE 5.41% (SD: 10.99). Mean SIA was 1.77D (1.61D) for the ECCE group, 1.17D (0.95D) for the SICS group and 0.77D (0.65D) for the PE group (p = 0.001). The magnitude of the difference between the SICS and the PE group was 0.4D. CONCLUSION: PE induced less astigmatism than SICS and ECCE in this study but the magnitude of the difference between SICS and PE was small. There was no significant difference in endothelial cell loss between the three groups.     

The outcome of the functioning filter after subsequent cataract extraction

OBJECTIVE: To evaluate and compare the outcome of functioning filtration surgery followed by cataract surgery with posterior intraocular lens implantation by both phacoemulsification and extracapsular cataract extraction (ECCE) techniques in glaucomatous eyes. PATIENTS AND METHODS: We retrospectively evaluated the clinical course of 77 eyes (68 patients) that after successful trabeculectomy, underwent cataract surgery by either phacoemulsification or ECCE techniques. We determined the frequency of partial and absolute failure following cataract surgery by either phacoemulsification or ECCE in eyes with functioning trabeculectomies. Partial failure of intraocular pressure (IOP), control after cataract extraction was defined as the need for an increased number of antiglaucoma medications or argon laser trabeculoplasty to maintain IOP < or =21mm Hg. Complete failure of IOP control after cataract surgery was defined as an IOP >21 mm Hg on at least two consecutive measurements one or more weeks apart or the performance of additional filtration surgery. Failure rates were calculated using the Kaplan-Meier actuarial method. Failure rates between phacoemulsification and ECCE subgroups were compared using the log rank test. RESULTS: The probability of partial failure by the third postoperative year after cataract surgery was 39.5% in the phacoemulsification subgroup and 37.3% in the ECCE subgroup. This small difference is not statistically significant (P = 0.48). The probability of complete failure by the fourth postoperative year after cataract surgery was 12.0% in the phacoemulsification subgroup and 12.5% in the ECCE subgroup. This difference is also not statistically significant (P = 0.77). At the 6-month follow-up visit, visual acuity of both groups improved one or more lines in 87.0% of patients, and worsened one or more lines in 3.9% of patients. Sixty-one percent achieved visual acuity of 20/40 or better. The most frequent complication was posterior capsular opacification requiring laser capsulotomy that occurred in 31.2% of patients. CONCLUSION: Cataract extraction by either phacoemulsification or ECCE following trabeculectomy surgery may be associated with a partial loss of the previously functioning filter and the need for more antiglaucoma medications to control IOP.     

青光眼小梁切除术后白内障超声乳化人工晶状体植入术临床分析

目的:分析青光眼小梁切除术后并发性白内障超声乳化联合软性人工晶状体植入的临床效果。方法:青光眼小梁切除术后白内障患者132例148眼,行鼻上或颞上象限角膜遂道切口或巩膜隧道切口白内障超声乳化吸除人工晶状体植入术,术后随访3～39mo,观察术后视力、眼压及并发症。结果:患者132例148眼术后视力恢复较满意,术后1wk矫正视力<0.05者8眼(5.4%),0.05～0.3者26眼(17.6%),～0.6者72眼(48.6%),～1.0者40眼(27.0%),>1.0者2眼(1.4%)。手术后眼压稳定,平均眼压15.23±3.42mmHg(1mmHg=0.133kPa)。手术并发症为早期角膜水肿及虹膜反应,均较轻,2～5d内消退。结论:经小切口超声乳化手术治疗青光眼小梁切除术后并发性白内障,操作简便,术后恢复快,散光小,并发症少,眼压控制好,在对青光眼术后并发性白内障的复杂情况方面似有优越之处。     

Small incisions to control astigmatism during cataract surgery

Astigmatic changes in three series of cataract surgical procedures were compared. Two series comprised eyes having phacoemulsification and implantation of a foldable silicone lens through a 3.0 mm to 4.0 mm incision or a 5.8 mm diameter polymethylmethacrylate (PMMA) lens through a 6.0 mm incision. The third series comprised eyes having a planned extracapsular cataract extraction (ECCE) procedure through a 10.0 mm incision and implantation of a PMMA posterior chamber lens. Surgically induced cylinder changes were compared by examining preoperative and postoperative dioptric cylinder power changes without regard to axis changes and by using vector analysis to compute induced cylinder for cases with axis changes. Both phacoemulsification series had similar mean induced cylinder levels, which were significantly less than mean induced cylinder in the ECCE group at both three and six months after surgery. Over 70% of the eyes in the two small incision phacoemulsification groups achieved an uncorrected visual acuity of 20/40 or better at three months, whereas only 28% of the ECCE group achieved that acuity. We concluded that the phacoemulsification procedure induced significantly less astigmatism and provided faster visual rehabilitation than the ECCE procedure. Furthermore, the use of small diameter PMMA IOLs inserted through small incisions minimized surgically induced cylinder in a way comparable to the use of foldable silicone implants, while maintaining good visual results with fewer postoperative complications.     

青光眼滤过术后经角膜切口的人工晶体植入术

目的：介绍经角膜小切口的青光眼滤过术后的白内障现代囊外摘除和人工晶体植入的方法及产观察。方法：对２３例２３只眼施行手术，上方角膜缘内１ｍｍ处，做６－７ｍｍ弦长切口，信封式或连续环形撕囊，水力分核娩出，后房型人工晶体植入。结果：２３只眼术后视力全 膜散光为１．１３Ｄ；眼压术前术后对比，无统计学差异；术中术后无严重并发症。结论：经角膜小切口治疗青光眼滤过后的白内障能取得良好效果面无严重并发症。     

高度近视眼白内障摘除时人工晶体选择的探讨

目的评价高度近视白内障摘除和后房型人工晶体植入时人工晶体屈光度和光学直径的选择方法。方法对眼轴＞２６ｍｍ的６０例（９４只眼）行白内障现代囊外或超声乳化摘除术,同时植入使术眼呈低度近视状态和不同光学直径的后房型人工晶体。结果患眼术后屈光状态符合低度近视,平均屈光度为－２．０７±１．９５Ｄ。较大光学直径的人工晶体,术后容易观察眼底。Ⅲ级核以下的白内障慎重行超声乳化摘除者,无并发症发生。结论轴性高度近视白内障摘除行人工晶体植入,应选择术后呈低度近视状态的人工晶体。较大光学直径有利于眼底观察。慎用超声乳化有利于减少术后散光。     

非超声乳化小切口白内障摘出人工晶状体植入

目的对比分析非超声乳化小切口白内障囊外摘出人工晶状体植入术与超声乳化吸出人工晶状体植入术的两种不同术式的效果。方法共95例（103眼）中非超声乳化小切口囊外摘出组37例（38眼），超声乳化组58例（65眼），对比观察两种术式的术后视力、散光及并发症。结果非超乳小切口白内障摘出术与超声乳化晶状体吸出术的术后视力、角膜散光及并发症差异无统计学意义。结论非超声乳化小切口白内障囊外摘出及人工晶状体植入术效果好、成本低、适合广大基层医院推广普及。     

Long-term course of surgically induced astigmatism

We performed an analysis of surgically induced astigmatism in 229 cases of extracapsular cataract extraction and posterior chamber lens implantation. The average length of follow-up for patients in this study was 34.4 months (2.87 years). We found that surgically induced astigmatism continued to change for at least three years after surgery. The preoperative astigmatism was found to have only minimal effect on the postoperative astigmatism if the corneal curvature was controlled with keratometry at the time of surgery. The optimal amount of with-the-rule astigmatism at three to five weeks postoperatively was found to be 0.75 diopter to 1.25 diopters for one surgeon and surgical technique.     

超声乳化与白内障囊外摘出术后散光与视力的对比

目的探讨白内障不同手术切口对术后视力和散光的影响。方法对白内障囊外摘出（ECCE）常规角膜缘10mm切口29例35眼和超声乳化（Phaco）反眉弓隧道式6mm切口37例44眼，于术后7d、1mo、3mo3个不同时期观察比较视力和角膜散光。结果Phaco术后角膜散光明显减轻且视力较ECCE明显提高（P＜0．05）。同时，随着时间的推移，手术切口修复，2种术式的差异呈逐渐减小趋势，3mo时二者的视力无显著性差异（P＞0．05）。结论超声乳化反眉弓隧道式6mm切口术式能早期有效提高视力及控制角膜散光。     

小切口白内障摘出联合人工晶体植入术

目的：探讨小切口不缝合白内障摘出联合人工晶体植入术的方法及效果。方法：４０例双眼白内障摘出联合人工晶体植入术的患者一只眼行小切口，另一只眼做常规切口进行前瞻性研究。结果：小切口组术后第１日至第３个月的散光变化为０．７０Ｄ，常规切口组为４．６６Ｄ，两组之间有非常显著性差异（ｔ检验，Ｐ〈０．００１）。小切口组术后第１、１周和１个月时的裸眼视力及第１周时矫正视力的平均值均高于对照组（ｔ检验，Ｐ〈０．０５     

两种不同术式治疗高度近视白内障的疗效对比

目的:评价两种不同手术方式治疗高度近视白内障疗效。方法:患者48例(65眼),其中30眼行囊外摘除,35眼行超声乳化摘除,术后均植入相应度数的人工晶状体。结果:术后视力较术前有明显提高,囊外摘除术后矫正视力与超声乳化术后矫正视力差异有显著性(︱t︱=2.867,P=0.006)。囊外摘除术后后囊膜轻度混浊4眼,局限性视网膜脱离2眼;超声乳化术后黄斑囊样水肿1眼,未见视网膜脱离。结论:晶状体摘除联合人工晶状体植入术作为治疗高度近视白内障的方法是有效的,超声乳化联合人工晶状体植入术与白内障囊外摘除联合人工晶状体植入术相比,安全性更高。     

Possible factors modifying the surgically induced astigmatism in cataract surgery.

PURPOSE: To investigate possible modifiers of the surgically induced astigmatism with special reference to age, gender, preoperative astigmatism, and the intraocular pressure. METHODS & PATIENTS: Data for one hundred and one cataract patients operated on with extracapsular cataract extraction and intraocular lens implantation were prospectively recorded and followed for six years. Different explanatory variables like age, gender, preoperative astigmatism and postoperative intraocular pressure (IOP) were considered. Astigmatic changes were calculated as Naeser's polar values. RESULTS: The surgically induced astigmatism was not significant at one year, but was significantly increased 3- and 6-years postoperatively. At the same time the keratometric axis made a shift toward against-the-rule astigmatism. The postoperative mean-IOP was lower at all controls. Multiple regression analysis showed that a large preoperative astigmatism, a low postoperative IOP, and high age resulted in more surgically induced astigmatism against-the-rule. CONCLUSION: The length and the architecture of the incision are known to have an influence on the surgically induced astigmatism in cataract surgery. In the present study we used a multiple regression analysis model to show a significant correlation between the surgically induced astigmatism and age, preoperative astigmatism, and postoperative IOP.     

Natural history of corneal astigmatism after cataract surgery.

Little information on the natural course of corneal astigmatism following cataract surgery exists. We report a prospective, computerized analysis of postoperative astigmatism, based on keratometry measurements, of 137 cases of extracapsular cataract extraction with intraocular lens implantation performed by one surgeon. No sutures were cut postoperatively. Surgery induced 1.44 diopters (D) of with-the-rule astigmatism at one month, which declined at a rate of 0.77 D and 0.35 D per month for the next two months, respectively, with a more gradual decline thereafter. The mean surgically induced astigmatism at the last postoperative visit ranged from 0.29 D at six months (minimum follow-up) to 1.23 D at 48 months; both were against-the-rule. Mean follow-up was 28.92 months. These findings may be technique specific and suggest that (1) corneal curvature continues to change slowly even two to four years postoperatively; (2) most patients develop against-the-rule astigmatism, thus more with-the-rule astigmatism is desirable in the early postoperative period; (3) selective suture removal is necessary only when significantly more than 3.00 D of surgically induced with-the-rule astigmatism is present.     

Change in corneal refractive power following artificial lens implantation

Report on the changes in the corneal refractive power of 284 eyes surgically treated for cataract, in which an IOL had been implanted. The mean corneal refractive power of the eyes was 43.31 +/- 1.43 D preoperatively and 43.39 +/- 1.46 D postoperatively (16th week). The postoperative astigmatism of 215 eyes in which a PCL had been implanted after ECCE was not higher than 1.1 +/- 1.1 D in the 16th postoperative week after selected removal of the nylon sutures. This study demonstrates that there is no statistically significant change in the mean corneal refractive power after cataract surgery with IOL implantation.     

经角膜切口行白内障摘除和人工晶体植入术

目的介绍经角膜切口行白内障囊外摘除和人工晶体植入的方法及疗效观察。方法用可调钻石刀在上方角膜缘内１．０～１．５ｍｍ处做梯形切口，行白内障囊外摘除和人工晶体植入手术，观察术后眼压、角膜内皮细胞及角膜性散光变化。结果４５只眼的眼压术前及术后对比，无统计学差异（Ｐ＞０．０５），角膜内皮细胞损失率为１２．５５％，术后平均循规性角膜散光０．９６ＤＣ。结论经角膜切口治疗青光眼小梁切除术后并发白内障、陈旧性葡萄膜炎瞳孔闭锁并发白内障及严重的糖尿病性白内障等，其疗效安全、可靠。