不同截囊方法的比较研究

以兔眼为实验材料，以临床操作模式为方法，在标准条件下，比较４种截囊术前囊膜辐射状撕裂的发生率，４种截囊术是：开罐式截囊，邮票（点刺）式截囊，线状截囊和环形撕囊术。实验结果证实，环形囊术较其它３种截囊方法有更多优点，应用本文介绍的后压法娩出晶体核后，撕囊术组中未见发生前囊膜辐射状撕裂，其它３组则１００％发生。     

Long-term results of various anterior capsulotomies and radial tears on intraocular lens centration

BACKGROUND AND OBJECTIVE: To evaluate the long-term effects of various anterior capsulotomies and radial tears on intraocular lens (IOL) centration. MATERIALS AND METHODS: Ninety-five eyes of 87 senile cataract patients operated with extracapsular technique were evaluated in IOL tilt and decentration with a new method of measurement. According to the type of anterior capsulotomy and number of radial tears, five groups were constituted as, can opener, envelope, continous curvilinear capsulorrhexis (CCC), CCC with one radial tear (relaxing incision at quadrant 12), and CCC with two relaxing incisions (relaxing incisions at quadrants 6 and 12), respectively. RESULTS: Early decentration and tilt in groups CCC and CCC with one radial tear were significantly lower than the other groups (P < 0.05). Late decentration and tilt in the CCC group were significantly lower than the other groups (P < 0.01). Highest values of tilt and decentration were determined in envelope capsulotomy. Additional symmetric relaxing incision at quadrant 6 revealed no effect on the prevention of decentration and tilt compared to one relaxing incision. CONCLUSION: CCC with one radial tear is not ideal but sufficient for IOL centration. All other anterior capsulotomy techniques, other than intact CCC, do not guarantee the IOL centration.     

Anterior capsular tears and loop fixation of posterior chamber intraocular lenses

Two hundred fifty consecutive postmortem eyes containing posterior chamber intraocular lenses (PC IOLs) were analyzed according to the presence and number of radial anterior capsular tears. Over 90% of cases had been done with the "can opener" technique. A surprisingly high percentage of cases, 86%, had one to five radial tears. Furthermore, our analysis showed that the most consistent and most permanent in-the-bag fixation was achieved when only one tear or less was present in the anterior capsule. Because this study shows that the incidence of radial tears is very high after nuclear expression with "can opener" capsulectomy, it provides a scientific basis supporting the transition toward the continuous circular capsulorhexis technique that is slowly evolving. The latter technique has been shown to minimize the incidence of anterior capsular radial tears. This may ultimately serve to decrease the incidence of PC IOL decentration, an important goal if the use of bimultifocal IOLs and IOLs with small or aspheric optics is to be successful.     

Capsule contraction syndrome

AIM: To analyse the occurrence of the anterior capsule contraction following cataract surgery. Capsule contraction syndrome (CCS) is defined as an extreme reduction in diameter of anterior capsulectomy, capsular bag diameter and, occasionally, displacement of the IOL after extracapsular cataract extraction. It is relatively frequent in pseudoexfoliation, advanced age, in association with uveitis, pars planitis and myotonic muscular dystrophy. MATERIALS AND METHODS: 5965 eyes of patients were operated on cataract between 1.01.1994 and 31.12.1997 in Tadeusz Krwawicz Chair of Ophthalmology and 1st Eye Hospital, Medical School in Lublin. Two types of surgical procedures were performed: "divide and conquer" phacoemulsification with 4.5-8 mm continuous curvilinear capsulorhexis (3385 eyes) and extracapsular cataract extraction with "can opener" capsulotomy (2580 eyes). RESULTS: 20 cases of clinically apparent CCS were referred to the Department: in the course of intensive postoperative inflammation--5, in patients over 80--4, in pseudoexfoliation syndrome--2, myotonic dystrophy--1, ectopia lentis--2, other causes--6. In order to improve visual acuity in 4 cases surgical removal of the distorted and opaque anterior capsule was performed, in 3 cases relaxing radial tears were done, in 3 cases secondary anterior capsulotomy was performed using Q-switched Nd:YAG laser. CONCLUSIONS: In cases where the occurrence of CCS is especially high large diameter capsulorhexis should be performed and IOL designed to provide maximal peripheral capsular bag expansion should be implanted.     

Comparison of anterior vitrectorhexis and continuous curvilinear capsulorhexis in pediatric cataract and intraocular lens implantation surgery: a 10-year analysis.

PURPOSE: To analyze the rate of inadvertent anterior lens capsular tears with vitrectorhexis or continuous curvilinear capsulorhexis (CCC) in pediatric cataract and intraocular lens (IOL) implantation surgery between January 1, 1997, and December 31, 2006. METHODS: Retrospective chart review, collecting for each eye: age at cataract surgery, type of anterior capsulotomy, any tearing of the capsule, and if yes, details of the tear. RESULTS: A total of 737 eyes were reviewed. Cases with a ruptured lens capsule that occurred prior to surgery were excluded. Eyes that received an anterior capsulotomy by any other method (n = 27) or eyes that did not receive an IOL (n = 100) were reviewed but excluded from final comparative analysis. Of the remaining 339 eyes, 19 eyes (5.6%) were noted to develop an anterior capsule tear (vitrectorhexis, 12 of 226 eyes, 5.3%; CCC, 7 of 113, 6.2%). These tears occurred during anterior capsulotomy in seven eyes, hydrodissection in one, cataract removal in three, and IOL insertion/manipulation in eight. In eyes operated for cataract at or before 72 months of age, the manual CCC technique was more likely to develop a tear (relative risk, 3.09) compared with eyes of older children (>72 months of age), where the vitrectorhexis technique was more likely to develop a tear (relative risk, 3.14). CONCLUSIONS: Vitrectorhexis is well suited for use in children less than 6 years of age due to their highly elastic anterior lens capsule. For children aged 6 years and older, manual CCC is the best technique because, by that age, capsule control and ease of capsulotomy completion has improved.     

二次撕囊术在白内障超声乳化摘除及人工晶状体植入术中的应用

目的 :探讨在白内障超声乳化摘除及人工晶状体植入术中行二次撕囊术 (secondarycapsulorhexis)的方法和作用。方法 :对 6例因皮质膨胀或液化眼行计划性的二次撕囊 ;10例行非计划性的二次撕囊 ,其中 3例因撕囊口过小难于植入囊袋内位固定人工晶状体 ,3例因超声乳化白内障摘除时前囊膜切迹破裂 ,4例因撕囊口偏中心 ,为防止囊膜收缩综合征发生以致遮盖瞳孔区而行二次撕囊。结果 :二次撕囊术后完成前囊膜连续曲线形撕囊 13眼 ,16眼均植入囊袋内位固定人工晶状体。结论 :二次撕囊术可使晶状体皮质膨胀或液化的白内障眼易于完成前囊膜连续曲线形撕囊 ;可避免白内障术中前囊膜切迹破裂以至进一步放射状撕裂 ;可维持完整曲线形撕囊口边缘 ,防止发生人工晶状体植入后光学部偏中心 ,囊襻异位 ;使过小撕囊口易于植入囊袋内位固定人工晶状体 ;使撕囊口偏下而让难于被吸除的上方赤道部残收稿日期 :2 0 0 2 -0 3 -2 6;修回日期 :2 0 0 2 -0 6-0 4作者简介 :周坚强 ( 1973 -) ,男 ,嘉兴人 ,眼科医师。通信作者 :周坚强 (E -mail:zhjq @mail.jxptt.zj.cn)。余皮质易于被吸除 ;可减少或避免过小前囊膜撕囊口或明显偏中心撕囊口发生囊膜收缩综合征 (capsulecontractionsyn drome)等。     

白内障截囊方式对后囊浑浊影响的调查分析

目的 分析不同截囊方式对后囊浑浊的影响。方法 回顾259眼以开罐式截囊、信封式截囊和连续环形撕囊3种方式截囊的白内障囊外摘出术后后囊浑浊的情况。结果 随访1年，开罐式截囊87眼术后发生后囊浑浊22眼（25.3%)；信封式截囊82眼术后发生后囊浑浊19眼（23.2%)；连续环形撕囊90眼术后发生后囊浑浊8眼（8.9%)。连续环形撕囊组后囊浑浊的发生率与其它两组有显著性差异（P＜0.05)。结论 连续环形撕囊有利于降低后囊浑浊的发生。     

Prospective experimental study of factors related to posterior chamber intraocular lens decentration.

The effect of posterior chamber intraocular lens (IOL) dimensions, design, style, loop fixation, and anterior capsular tears on decentration were investigated in an experimental model. Nine posterior chamber IOLs of various designs and styles with loop diameters between 12.0 and 14.0 mm and optic diameters between 5.0 and 7.0 mm were implanted in human eyes obtained post mortem. Symmetrical and asymmetrical fixation were investigated in eyes with and without radial tears using the Miyake posterior view technique. Location of IOL loops proved to be the most significant factor in IOL decentration. Decentration was least with symmetrical bag/bag fixation and no radial tears (mean = 0.20 +/- 0.05 mm). Asymmetrical bag/sulcus fixation in the presence of anterior capsular tears was associated with the highest decentration rate (mean 0.68 +/- 0.28 mm). Optic size and total loop diameter had no apparent effect on IOL centration in the immediate postoperative period.     

Effect of intraocular lens and anterior capsule opening type on posterior capsule opacification.

PURPOSE: To determine the effect of intraocular lens (IOL) type and anterior capsulectomy technique on the incidence of posterior capsule opacification. SETTING: Department of Ophthalmology, Medical Faculty, University of Ondokuz Mayis, Samsun, Turkey. METHODS: Three hundred two eyes of 294 patients were examined retrospectively after IOL implantation in the capsular bag performed between February 1991 and November 1996. Patients were divided into 3 groups according to IOL type: poly(methyl methacrylate) (PMMA); heparin-surface-modified PMMA (HSM PMMA); plate-haptic silicone. Envelope capsulectomy or continuous curvilinear capsulorhexis (CCC) was used. Mean follow-up was 27 months (range 12 to 33 months). RESULTS: Posterior capsule opacification developed in 47 cases (15.6%): 21.7% in the PMMA lens group after planned extracapsular cataract extraction (ECCE), 17.4% in the HSM PMMA lens group after planned ECCE, and 7.7% in the plate-haptic silicone lens group after phacoemulsification. Posterior capsule opacification occurred less in patients who had anterior capsulectomy using the CCC technique (11.5%) than in those having an envelope capsulectomy (24.5%) (P < .05). Posterior capsule opacification was significantly less in eyes with a capsular-bag-fixated plate-haptic silicone lens than in those with a PMMA or HSM PMMA IOL (P < .05). CONCLUSION: This study demonstrated that the anterior capsulectomy technique and the IOL type influence the incidence of PCO.     

Analysis of capsular bag defects and intraocular lens positions for consistent centration

Radial anterior capsular tears frequently occur in posterior-chamber iris-plane phacoemulsification cases. These tears extend to the capsular bag equator and can allow the knee of an in-the-bag posterior chamber intraocular lens (IOL) to unfold a smaller anterior capsular remnant. This unfolding can allow the knee of the IOL loop to extend beyond the capsular equator, leading to IOL decentration. Typical anterior capsular radial tear configurations along with guidelines for IOL design selection and orientation after recognition of these tears are presented. Proper IOL centration was achieved in 255 of 262 patients (97%) in a study observing these guidelines.