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.     

Scheimpflug measurement of intraocular lens position after piggyback implantation of foldable intraocular lenses in eyes with high hyperopia

PURPOSE: To investigate the position of 3-piece foldable intraocular lenses (IOLs) after piggyback implantation for high hyperopia. SETTING: University Eye Hospital, Johann Wolfgang Goethe University, Frankfurt am Main, Germany. METHODS: Eight eyes of 5 highly hyperopic patients had phacoemulsification and implantation of 2 foldable IOLs. In 3 eyes, both IOLs were implanted in the capsular bag. In 5 eyes, 1 IOL was placed in the capsular bag and the second IOL in the ciliary sulcus. Intraocular lens optic tilt and decentration, combined thickness of both IOLs, and anterior chamber depth (ACD) were measured postoperatively over a period of 18 months using Scheimpflug photography. RESULTS: All eyes with both IOLs in the capsular bag showed interpseudophakic opacification, with a mean increase in combined IOL thickness of 0.4 mm, a decrease in ACD of 0.3 mm, and a corresponding hyperopic shift of 4.00 diopters. Eyes in which the anterior IOL was placed in the ciliary sulcus showed no changes in refraction or combined IOL thickness. In these eyes, the anterior IOL had a higher mean decentration (0.49 mm +/- 0.20 [SD] after 12 months) than the posterior IOL (0.21 +/- 0.13 mm after 12 months). CONCLUSIONS: Piggyback IOL implantation with placement of 2 foldable IOLs in the capsular bag can be followed by a hyperopic shift that may be caused in part by displacement of the IOLs. Placement of the anterior IOL in the ciliary sulcus can lead to higher decentration of this IOL.     

Intraocular lens decentration and posterior capsule opacification: anatomo-pathologic findings after implantation of AMOSI40 IOLS

PURPOSE: To evaluate the incidence of intraocular lens (IOL) decentration and posterior capsule opacification (PCO) after implantation of a three-piece posterior chamber silicone IOL in a series of eyes examined postmortem. METHODS: Twenty-three pseudophakic enucleated human cadaver eyes, implanted with AMO SI40NB IOLs after phacoemulsification, were analyzed. Eyes obtained postmortem were sectioned at the equatorial plane and the anterior segment photographed from a posterior view. Location of IOL optic and haptics, type of fixation, and centration of IOL was evaluated. PCO was graded and the presence of Nd:YAG laser posterior capsulotomy was noted. RESULTS: Mean age at the time of surgery was 77.83 years, mean time since implantation was 18.26 months. In all the eyes examined, IOL haptics were positioned in the capsular bag. Mean decentration was 0.20+/-0.16 mm. No correlation was found between IOL decentration and time since implantation. The degree of peripheral PCO ranged from none (13.0%) to mild (39.1%) to moderate (26.1%) to severe (21.7%). The degree of central PCO ranged from none (52.2%) to mild (30.4%) to moderate (4.3%). Three patients (13.0%) underwent Nd:YAG laser posterior capsulotomy. CONCLUSIONS: A very good centration can be obtained when silicone AMOSI40NB IOLs are correctly implanted with the haptics inside the capsular bag. About half of the implants showed no central PCO while Nd:YAG laser posterior capsulotomy rates documented a relatively low PCO 18 months after surgery. A careful in the bag haptics placement is needed in order to reduce the IOL decentration and to prevent central PCO.     

Comparison of various capsulectomy techniques in cataract surgery. An experimental study]

Radial tears at the edge of an anterior capsulectomy are often associated with the occurrence of intraocular lens (IOL) loops coming out of the capsular bag with subsequent IOL decentration. We analyzed the incidence of radial tear formation in 40 human eyes obtained postmortem. These eyes were randomly assigned to four groups: "can opener," linear capsulotomy, capsulopuncture ("postage stamp"), and continuous curvilinear capsulorhexis (CCC). The CCC appeared to be much less likely to be associated with anterior capsular radial tears as opposed to the other three techniques. With the nucleus expression technique used in this study, radial tears occurred in all cases of "can opener," linear capsulotomy and capsulopuncture, whereas no tears occurred with the CCC technique. The results of this study show that CCC is currently the best available anterior capsulectomy procedure for minimizing the incidence of radial tears and sequelae such as decentration.     

Influence of intraoperative complication on intraocular rigid lens fixation in pediatric cataract surgery

PURPOSE: This paper presents the intraoperative complications in pediatric cataract surgery with IOL implantation and their influence on fixation place. MATERIAL AND METHODS: 384 eyes of 276 children undergone operative procedure for cataract. Anterior capsulorhexis, lens cortical aspiration, primary posterior capsulorhexis with anterior vitrectomy and IOL implantation were done in all eyes. The place of IOL implantation was capsular sac or ciliary sulcus. RESULTS: There were no serious intraoperative complications but in cases with large anterior (5.2%) and posterior (14.6%) radial capsule tears, vitreous loss (12.3%), and hemorrhage (5.5%) to anterior and posterior chamber the IOL was fixated at ciliary sulcus (in 37.5%). CONCLUSIONS: The surgical procedure is useful and safe in the management of pediatric cataract. Location of an IOL in the ciliary sulcus in a child, is acceptable. To avoid decentration in this cases, we recommend rigid PMMA IOLs.     

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.     

囊袋张力环植入治疗晶状体悬韧带异常的2年临床效果

目的评价在晶状体悬韧带异常情况下行超声乳化白内障吸除术时植入囊袋张力环（CTR）来提供晶状体囊袋支持的中长期临床效果。方法对2003年1月至2004年7月期间因晶状体悬韧带松弛或部分断裂或合并白内障在我院行超声乳化白内障吸除及CTR和人工晶状体（IOL）植入术的19例患者（22只眼）进行为期2年的随访。随访指标为最佳矫正视力和屈光度数、眼压、CTR和IOL及囊袋复合体的位置、晶状体后囊膜混浊（PCO）和晶状体囊袋的收缩程度。应用眼前节成像系统Pentacam采集各眼的Scheimpflug图像,分析术后1、6、12和24个月IOL的偏心值与倾斜度。结果术后2年随访结果：末次随访最佳矫正视力较术前提高≥2行者20只眼（90.9％）,提高1行者2只眼（9．1％）。CTR位置：21只眼CTR位于囊袋内,1只眼CTR部分脱出于囊袋外。IOL位置：22只眼的IOL均位于囊袋内,术后1个月1只眼轻度偏中心,术后2年5只眼轻度偏中心。PCO情况：末次随访3只眼（13．6％）因重度PCO行掺钇钕石榴石激光后囊膜切开,余19只眼为轻度PCO,无需处理。晶状体囊袋收缩程度：末次随访1只眼囊袋中度收缩。Pantacam检查术后1、6、12和24个月IOL的平均偏心值分别为（0．393±0．094）、（0.406±0．094）、（0.415±0．093）、（0.463±0．172）mm,术后1、6与24个月比较,差异有统计学意义（P〈0．05）。倾斜度分别为2．637°±0．369°、2．653°±0．349°、2．682°±0.348°、2．714°±0．360°,各组间差异无统计学意义（P=0.220）。结论CTR合并IOL植入治疗晶状体悬韧带异常可获得良好视力。术后2年的随访观察证实CTR的植入抑制了PCO和囊袋收缩的发生,并维持IOL在囊袋内位置的良好稳定性。（中华眼科杂志,2007．43：519-524）     

Pathological evaluation of postmortem human eyes implanted with a new single-piece hydrophobic acrylic lens

PURPOSE: To report the pathological findings in 14 human cadaver eyes implanted with a single-piece AcrySof(Alcon Laboratories) posterior chamber intraocular lens (IOL). SETTING: David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Methods: Fourteen human autopsy eyes implanted with a single-piece AcrySof (SA30AL) IOL were evaluated. The eyes were sectioned at the equatorial plane, and the anterior segment containing the IOL in the capsular bag was evaluated from a posterior perspective (Miyake-Apple view) and from an anterior perspective (surgeon's view) after removal of cornea and iris. They were then processed through paraffin, sectioned, and stained with hematoxylin-eosin, periodic acid-Schiff, and Masson's trichrome and examined under light microscopy. RESULTS: All IOLs had symmetric in-the-bag fixation. Slight decentration was measured in 1 eye, which also had an anterior capsule tear. Grade 1 anterior capsule opacification was present in 9 eyes. No central posterior capsule opacification or posterior capsule folds were observed in any eye. Soemmering's ring formation was observed in 5 eyes. Zonular stretch caused by different degrees of capsular bag contraction was present in 4 eyes without decentration of the IOL. CONCLUSIONS: Analyses of pseudophakic cadaver eyes from the posterior (Miyake-Apple) view, complemented by microscopic analyses, proved useful in the evaluation of IOL-capsular bag interaction. These studies are more important in cases of newly introduced lens designs.     

Akreos Adapt人工晶状体十字形袋／沟固定法在后囊大破孔时的应用

目的 观察Akreos Adapt亲水性丙烯酸酯折叠式人工晶状体（IOL）十字形袋/沟固定法植入在外伤后或白内障术中出现的后囊大破孔时应用的临床效果.方法 对31例（31眼）后囊大破孔者采用十字形袋/沟固定法植入Akreos Adapt亲水性丙烯酸酯折叠式IOL.随访期内观察其术后视力及视觉症状、术后炎症反应、IOL位置及固定状态、囊膜混浊程度、瞳孔和眼压等情况.结果 术后所有眼视力均较术前提高,最佳矫正视力0.1～0.2者4眼,0.3～0.4者5眼,≥0.5者22眼.所有术眼的IOL均在位,基本居中、无移位,视轴透明,未见严重的术后炎症反应或IOL相关并发症,瞳孔及眼压正常.结论 在后囊大破孔但连续环形撕囊完整时可采用十字形袋/沟固定法植入Akreos Adapt亲水性丙烯酸酯折叠式IOL,该法简便、快捷、安全,植入后IOL位置稳定居中,并有良好的生物相容性和眼内稳定性.     

Lens anatomical principles and their technical implications in cataract surgery. Part I: The lens capsule

Optimal fixation and position of an intraocular lens (IOL) is achieved when it is located in the capsular bag. A peripheral tear from the central opening to the lens periphery is associated with a high incidence of dislocation of at least one loop from within the capsular bag and lens decentration. A central round continuous capsulectomy (capsulorhexis), within the zonule-free area, provides long-term and balanced IOL fixation. To perform a well-controlled capsulectomy, a deep and stable anterior chamber should be maintained throughout the surgery. This is achieved by using a continuous anterior chamber maintainer that regulates the pressure in the anterior chamber. This paper reviews the clinical anatomical guidelines of the lens capsule and the anterior chamber and presents the authors' preferred technique for optimal anterior capsulectomy.     

Capsulorhexis ovaling and capsular bag stretch after rigid and foldable intraocular lens implantation: experimental study in pediatric human eyes

PURPOSE: To compare the amount of capsulorhexis ovaling and capsular bag stretch produced by various intraocular lenses (IOLs) implanted in pediatric human eyes obtained post-mortem. SETTING: David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: In this nonrandomized comparative study, 16 pediatric human eyes obtained postmortem were divided into 2 groups: Eight eyes were obtained from children younger than 2 years (Group A), and 8 eyes were obtained from children older than 2 years (Group B). All eyes were prepared according to the Miyake-Apple posterior video technique. Six types of rigid and foldable posterior chamber IOLs manufactured from poly(methyl methacrylate) (single-piece), silicone (plate and loop haptics), and hydrophobic acrylic (single-piece and 3-piece AcrySof, Alcon Laboratories) biomaterials were implanted. The capsulorhexis opening and capsular bag diameters were measured before IOL implantation and after in-the-bag IOL fixation with the haptics (or the main axis) at the 3 to 9 o'clock meridian. The percentage of ovaling of the capsulorhexis opening was calculated by noting the difference in the opening's horizontal diameter before and after IOL implantation. The percentage of capsular bag stretch was also calculated by noting the difference in the horizontal capsular bag diameter before and after IOL implantation. RESULTS: All IOLs produced ovaling of the capsulorhexis opening and stretching of the capsular bag parallel to the IOL haptics. There were significant differences in capsulorhexis ovaling and capsular bag stretch (P<.001, analysis of variance) between the 6 IOL types in each group of eyes. The postimplantation difference was significant only between the single-piece hydrophobic acrylic IOL (AcrySof) and the other IOLs. The single-piece hydrophobic acrylic IOL was associated with significantly less capsulorhexis ovaling and capsular bag stretch in both groups (mean 12.06% +/- 0.59% [SD] and 7.6% +/- 1.47%, respectively). CONCLUSIONS: Modern rigid and foldable IOLs designed for the adult population implanted in the capsular bag of infants and children produced variable degrees of capsulorhexis ovaling and capsular bag stretch. The Miyake-Apple posterior video technique confirmed the well-maintained configuration of the capsular bag (with minimal ovaling) after implantation of a single-piece hydrophobic acrylic IOL because of its flexible haptic design.     

A short haptic diameter modified J-loop intraocular lens for improved capsular bag performance

The laboratory and clinical characteristics of a modified J-loop intraocular lens (IOL) are presented. The lens features a 6 mm polymethylmethacrylate optic with uniplanar polypropylene loops of a 12 mm overall haptic diameter. The haptic design has a low resistance to compression at all diameters down to 9 mm. The relationship of the haptic configuration to the architecture of the capsular bag facilitates easy capsular bag implantation and consistent IOL centration in eyes with small and moderate capsular bag diameters. Three hundred fourteen lenses have been implanted over a one year period with no instance of asymmetric capsular bag-ciliary sulcus IOL placement, optic decentration, or pupillary capture.     

Anterior capsule opacification: correlation of pathologic findings with clinical sequelae

OBJECTIVE: To evaluate the degree of anterior capsule opacification (ACO) in human eyes obtained postmortem containing various rigid and foldable posterior chamber intraocular lens (PC-IOL) designs and compare the findings with clinical sequelae of capsular shrinkage. DESIGN: Comparative autopsy tissue study with clinicopathologic correlations. MATERIALS: Three hundred formalin-fixed human eyes containing the following PC-IOL styles were analyzed: (1) one-piece polymethyl methacrylate (PMMA) optic-PMMA haptic (n = 50), one-piece silicone-plate IOL, with large (2) or small (3) fixation holes (n = 35), (4) three-piece PMMA optic-Prolene haptic (n = 50), (5) three-piece acrylic optic-PMMA haptic (n = 55), three-piece silicone optic with PMMA (6) or polyimide (7) haptics (n = 30), and (8) three-piece silicone optic-Prolene haptic (n = 80) lenses. TESTING: The eyes were sectioned in the equatorial plane for gross examination of the capsular bag from a posterior view. The cornea and iris were then excised for evaluation from an anterior view. MAIN OUTCOME MEASURES: ACO was scored in each eye from 0 to IV, according to the degree/area of capsule opacification. Capsulorrhexis size and IOL decentration were measured with calipers. RESULTS: The overall differences among the IOL groups regarding the three parameters were significant (ACO score: P < 0.001; capsulorrhexis diameter: P = 0.036; IOL decentration: P = 0.012). Mean ACO scores were highest with the large- and small-hole one-piece silicone-plate lenses (2.543 +/- 0.950) and lowest with the three-piece acrylic optic-PMMA haptic lenses (0.600 +/- 0.710). Of 10 cases of capsulorrhexis phimosis observed in the study, 7 cases were associated with three-piece silicone optic-Prolene haptic lenses, which also presented the highest mean decentration (0.375 +/- 0.601 mm). CONCLUSIONS: Our results confirm previous histopathologic observations that the rate of ACO is the lowest with acrylic lenses and higher with plate-haptic silicone IOLs. Nevertheless, clinical sequelae of capsular shrinkage are also very important with three-piece silicone optic-Prolene haptic designs. Thus, IOL material and design are significant factors in the development of ACO, but they ultimately also influence the clinical presentation of capsular shrinkage.     

Ciliary sulcus anatomical dimensions

Trans-scleral ciliary sulcus and iris suture fixation of posterior chamber intraocular lenses (IOLs) in eyes without posterior capsular support are techniques gaining wider acceptance. Primary indications are IOL exchange in pseudophakic bullous keratopathy and secondary IOL insertion in aphakia. Accurate placement of the posterior chamber lens loops within the ciliary sulcus is based on knowledge of ciliary sulcus anatomy. Nineteen postmortem eyes were sectioned in the coronal plane to expose the posterior iris border and the ciliary body. Ciliary sulcus diameters were measured, and the mean diameter was 11.0 +/- 0.37 mm. The mean limbus-ciliary sulcus distance was then measured by passing 26-gauge needles through the ciliary sulcus and sclera. The mean limbus-ciliary sulcus distance was 0.9 mm. These measurements may guide ophthalmic surgeons in choosing appropriate IOL designs for IOL exchange or secondary IOL procedures.     

Effect of Nd∶YAG laser treatment for correlative capsular syndrome

ObjectiveTo study the clinical effect of Nd∶YAG laser treatment for correlative capsular syndrome after cataract phacoemulsification with foldable intraocular lenses （IOL） implants. MethodsThis was a retrospective case-controlled study. Thirty-three patients （33 eyes） diagnosed with correlative capsular syndrome who underwent cataract phacoemulsification with foldable IOL implantation were treated with Nd∶YAG laser. Twelve eyes were in the capsular contraction syndrome （CCS） group and 21 eyes were in the capsular block syndrome （CBS） group. In the CCS group, radial cuts were made in 10 eyes for anterior capsular fibrillar contraction rings and posterior capsulotomy with Nd∶YAG laser was used in 2 eyes. Seven eyes with early postoperative CBS underwent peripheral anterior capsulotomy with Nd∶YAG laser and fluid from the capsular bag was drained into the anterior chamber. Two of them had procedures that were combined with posterior capsulotomy. Fourteen eyes in the CBS group with late postoperative CBS underwent posterior capsulotomy with Nd∶YAG laser to liberate fluid from the capsular bag into the vitreous cavity. All cases were followed up for 6 months. ResultsIn the CCS group postoperatively, the anterior capsular fibrillar contraction rings were relaxed, capsular bag contraction disappeared, the anterior capsular transparent zones were enlarged, IOLs were in the central position, the lenses were stretched and there was no deviation in IOL tilt or capsular bag capture. In the CBS group postoperatively, IOLs were in good position, the posterior capsules were attached to the posterior surface of the lenses without spaces, and capsular bag block was relieved effectively. Pupillary block had disappeared, the depth of the anterior chamber had deepened and IOP was normal in all 7 eyes with early CBS. Uncorrected visual acuity （UCVA） improved at different degrees postoperatively in the CBS and CCS groups. ConclusionNd∶YAG laser is a good choice for correlative capsular syndrome after cataract phacoemulsification with foldable IOL implantation. It has a definite clinical effect and is a simple and safe procedure.     

白内障术中后囊膜破裂行后囊膜连续曲线形撕囊术

目的：讨论白内障囊外摘除、超声乳化摘除及针吸摘除术中后囊膜破裂时行后囊膜连续曲线形撕囊术（ｐｏｓｔｅｒｉｏｒ ｃｏｎｔｉｎｕｏｕｓ ｃｕｒｖｉｌｉｎｅａｒ ｃａｐｓｕｌｏｒｈｅｘｉｓ,ＰＣＣＣ）的方法和作用。方法：利用撕囊镊对１０例（１０眼）白内障摘除术中后囊膜破裂眼行ＰＣＣＣ,５例联合行前段玻璃体切除术。结果：１０例后囊膜破裂后行ＰＣＣＣ眼９例成功完成ＰＣＣＣ,１ 均植入后房人工晶体。术后观察１月～３年（平均１６月）,９例行ＰＣＣＣ眼视轴均清晰,未发生视网脱离及后发性白内障,无明显的人工晶体光学部偏中心或人工晶体异位。结论：ＰＣＣＣ可有效避免后囊膜破孔进一步无限放射状撕裂,保持周边后囊膜的完整性。使人工晶体稳固于囊袋内。     

Comparison of tilt and decentration of 1-piece and 3-piece hydrophobic acrylic intraocular lenses

PURPOSE: To determine the amount of tilt and decentration of 1-piece and 3-piece hydrophobic acrylic intraocular lenses (IOLs) in patients having cataract surgery. SETTING: Department of Ophthalmology, Gulhane Military Medical Academy and Medical School, Ankara, Turkey. METHODS: Eighty-eight patients having phacoemulsification with IOL implantation were divided into 2 groups. One group received a 3-piece hydrophobic acrylic IOL with 12.5 mm poly(methyl methacrylate) haptics and the other, a 1-piece hydrophobic acrylic IOL with 12.5 mm haptics. The amount of IOL decentration and tilt was quantitated using Purkinje reflections and photographic documentation at the last postoperative control. The results of the 2 groups were compared. RESULTS: Bag fixation of the IOL and an intact continuous curvilinear capsulorhexis (CCC) were confirmed in all cases at the last postoperative control, which was at a mean of 27.1 months +/- 5.4 (SD) and 26.7 +/- 4.4 months in the 3-piece group and 1-piece group, respectively (P = 0.659). There was no significant difference between groups in the percentage of patients with measurable tilt and decentration and of patients without measurable tilt and decentration (P = .956). The mean IOL tilt was 2.72 +/- 0.55 degrees in the 3-piece group and 2.70 +/- 0.84 degrees in the 1-piece group and the mean IOL decentration, 0.39 +/- 0.13 mm and 0.34 +/- 0.08 mm, respectively. There were no significant between-group differences in tilt or decentration (P = .897 and P = .103, respectively). CONCLUSION: There were no significant differences in tilt and decentration between 1-piece and 3-piece hydrophobic acrylic IOLs in eyes with capsular bag IOL implantation and an intact CCC.     

Early decentration of plate-haptic silicone intraocular lenses

We report 4 eyes of a consecutive series of 1299 that developed early decentration of a 10.5 mm diameter plate-haptic silicone intraocular lens (IOL) after uneventful phacoemulsification. All eyes had an intact continuous curvilinear capsulorhexis (CCC) with the IOL placed in the capsular bag. After an initial period of good vision, patients noted the onset of glare or monocular diplopia between 1 and 5 weeks after surgery. On examination, there was no significant anterior capsule contraction; however, the edge of the IOL optic was visible in the undilated pupil. There was adhesion between the anterior and posterior capsules at the margin of the CCC that maintained the IOL decentration. Decentration recurred in 1 eye after the IOL was rotated 90 degrees and recentered. Symptoms resolved in 3 eyes after the IOL was removed and replaced with a rigid IOL with a larger diameter optic.     

Effect of a capsular tension ring on intraocular lens decentration and tilting after cataract surgery

PURPOSE: To evaluate the effect of a capsular tension ring (CTR) on the tilting and decentration of intraocular lenses (IOLs) after cataract surgery. SETTING: Department of Ophthalmology, Ilsan Paik Hospital, Inje University, Kyunggyi-do, Korea. METHODS: Cataract surgery was performed in both eyes of 20 patients ranging in age from 57 to 75 years. The 40 eyes were divided into 2 groups based on whether a CTR (Lucid Korea) was implanted. Each patient received a CTR in 1 eye only. All IOLs (AcrySof MA60BM, Alcon) were implanted in the capsular bag after a continuous curvilinear capsulorhexis smaller than the IOL optic was created and phacoemulsification performed. The extent of IOL tilting and decentration was measured with the EAS-1000 anterior eye segment analysis system 7, 30, and 60 days after surgery. RESULTS: The extent of IOL decentration was statistically significantly less in eyes with both an IOL and CTR than in those with an IOL only. The mean decentration in the CTR-IOL group was 0.38 mm +/- 0.16 (SD) at 7 days, 0.43 +/- 0.15 mm at 30 days, and 0.42 +/- 0.17 mm at 60 days. The mean values in the IOL-only group were 0.49 +/- 0.11 mm, 0.53 +/- 0.14 mm, and 0.57 +/- 0.16 mm, respectively. The amount of IOL tilting was also significantly less in the CTR-IOL group. The mean tilting in the CTR-IOL group was 2.22 +/- 0.46 degrees at 7 days, 2.36 +/- 0.50 degrees at 30 days, and 2.47 +/- 0.40 degrees at 60 days. The mean values in the IOL-only group were 3.14 +/- 0.65 degrees, 2.91 +/- 0.67 degrees, and 3.06 +/- 0.56 degrees, respectively. CONCLUSION: These results indicate that the CTR reduces undesirable postsurgical IOL movement for at least 60 days.     

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation

PURPOSE: To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size. SETTING: Eye Hospital, Johannes Gutenberg-University, Mainz, Germany. METHODS: The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics). RESULTS: The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% (P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant (P =.001). CONCLUSIONS: A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.