Postoperative course of intraocular pressure after cataract surgery with combined primary posterior capsulorhexis and posterior optic buttonholing

PURPOSE: To evaluate the natural course of intraocular pressure (IOP) after cataract surgery with combined primary posterior continuous curvilinear capsulorhexis (PPCCC) and posterior optic buttonholing (POBH) of the intraocular lens (IOL) in adult patients. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: Fifty consecutive patients with age-related cataract awaiting cataract surgery under topical anesthesia in both eyes were enrolled prospectively. In randomized order, cataract surgery with combined PPCCC and POBH was performed in 1 eye. In the fellow eye, cataract surgery was performed conventionally with in-the-bag IOL implantation and the posterior lens capsule kept intact. Standardized IOP measurements by Goldmann applanation tonometry were performed 1, 2, 4, 6, 8, and 24 hours postoperatively. Follow-up IOP measurements were taken at 1 week and 1 month. Twenty-five patients received 1-time IOP-lowering medication immediately after cataract surgery; the other 25 did not receive IOP-lowering drops. RESULTS: During the first 24 hours postoperatively, no significant differences in IOP were observed between the PPCCC-POBH group and the conventional surgery group (P>.05). No IOP peaks greater than 27 mm Hg were observed in any eye. One week and 1 month postoperatively, no significant differences in IOP were found between groups (P>.05). The use of IOP-lowering drops significantly reduced postoperative IOP. However, no IOP spikes >27 mm Hg were found with and without the use of IOP-lowering drops. CONCLUSION: The course of IOP after cataract surgery with combined PPCCC and POBH showed the technique to be as safe as conventional cataract surgery with in-the-bag IOL implantation.     

Objective assessment of intraocular flare after cataract surgery with combined primary posterior capsulorhexis and posterior optic buttonholing in adults

AIM: Combining primary posterior capsulorhexis (PPC) and posterior optic buttonholing (POBH) in cataract surgery is an innovative approach to prevent after-cataract formation effectively and to increase postoperative stability of the intraocular lens (IOL). The present study was designed to compare the postoperative intraocular flare after cataract surgery with combined PPC and POBH to conventional in-the-bag implantation of the IOL. METHODS: Fifty consecutive age-related cataract patients with cataract surgery under topical anaesthesia in both eyes were enrolled prospectively into a prospective, randomised clinical trial. In randomised order, cataract surgery with combined PPC and POBH was performed in one eye; in the other eye cataract surgery was performed conventionally with in-the-bag IOL implantation keeping the posterior lens capsule intact. Intraocular flare was measured 1, 2, 4, 6, 12 and 24 h postoperatively, as well as 1 week and 1 month postoperatively, using a KOWA FC-1000 laser flare cell meter. RESULTS: The peak of intraocular flare was observed in POBH eyes and eyes with in-the-bag IOL implantation 1 h postoperatively. In both groups, the response was steadily decreasing thereafter. During measurements at day 1, small though statistically significant higher flare measurements were observed in eyes with in-the-bag IOL implantation (p<0.05). At 1 week and 1 month postoperatively, intraocular flare measurements were comparable again (p>0.05). CONCLUSION: Cataract surgery with combined PPC/POBH showed slightly lower postoperative anterior chamber reaction compared to conventional in-the-bag implantation during 4-week follow-up, indicating that POBH might trigger somewhat less inflammatory response. This could be explained by the posterior capsule sandwiching between the optic and the anterior capsule, preventing direct contact-mediated myofibroblastic trans-differentiation of anterior lens epithelial cells with consecutive cytokine depletion.     

Routine posterior optic buttonholing for eradication of posterior capsule opacification in adults: report of 500 consecutive cases

PURPOSE: To study the efficacy of posterior optic buttonholing (POBH) through a primary posterior capsulorhexis (PPCCC) to preserve full capsular transparency, and its potential as a routine alternative to standard in-the-bag implantation of sharp-edged optic intraocular lenses (IOLs). SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: After standard cataract removal, a PPCCC 4.0 to 5.0 mm in diameter was performed and the optic of a 3-piece IOL buttonholed posteriorly. One third of the eyes additionally had extensive anterior capsule polishing. All surgeries were performed under topical anesthesia. RESULTS: The first 500 consecutive surgeries were evaluated. In 11 eyes, POBH was not performed as planned. In 4 cases, anterior capsulorhexis fixation of the optic was used as an alternative. In the early series, vitreous entanglement was seen in 5 eyes, of which 1 case prompted translimbal anterior vitrectomy. No case of cystoid macula edema was observed. One case of peripheral retinal detachment in a highly-myopic eye 4 months postoperatively appeared to be unrelated to the surgery. All lenses were well-centered without tilt, and both capsule leaves remained clear especially after additional polishing. CONCLUSION: Posterior optic buttonholing precludes lens epithelial cells from accessing the retrolental space. The sandwiched posterior capsule blocks optic contact and thus fibrosis of the anterior capsule. Posterior optic buttonholing avoids after-cataract independent of optic edge design. Anterior capsule polishing adds to its efficacy by excluding any residual fibrosis. Surgery under topical anesthesia was well-controlled and safe. Posterior optic buttonholing may become a routine alternative to standard in-the-bag IOL implantation when supported by a longer follow-up.     

Posterior capsulorhexis combined with optic buttonholing: an alternative to standard in-the-bag implantation of sharp-edged intraocular lenses? A critical analysis of 1000 consecutive cases

BACKGROUND: Current after-cataract prevention relies on optimizing the natural barrier effect of the optic rim against lens epithelial cell (LEC) migration. However, deficiencies in circumferential capsular bag closure caused by the intraocular lens (IOL) haptic or delayed secondary re-division of the fused capsules by Soemmering s ring formation lead to primary or secondary barrier failure. Consequently, surprisingly high posterior laser capsulotomy rates have been reported long-term, even with optimal capsular surgery and the most widespread hydrophobic acrylic IOLs, considered to be the most advanced. Intraoperative removal of the central posterior capsule has been shown to be effective in further reducing LEC immigration. However, efficacy has turned out to be limited because of the propensity of LECs to use the posterior optic surface as an alternative scaffold. MATERIAL AND METHODS: Technique: in pediatric cataract surgery, buttoning-in of the optic into an adequately-centered posterior capsulorhexis opening has been described previously. This technique was further elaborated and applied as the standard technique in a large series of adult eyes. In general, the diameter aimed at was 5-6 mm for the anterior, and 4-5 mm for the posterior capsulorhexis. Between September 2004 and June 2007, 1000 consecutive cases have thus been performed and systematically evaluated. One hundred and fifty eyes additionally underwent extensive anterior LEC abrasion. Another sub-series investigated the option of further reducing capsular fibrosis by creating an anterior capsulorhexis larger than the optic. Evaluation: special scrutiny was applied to detect postoperative vitreous entrapment. Regeneratory and fibrotic after-cataract formation were both meticulously followed-up. Postoperative pressure course, anterior segment inflammation, macular thickness and morphology, as well as axial optic stability and optic centration, were evaluated in intraindividual comparison studies. RESULTS: A low rate of vitreous complications was found, which can be avoided by appropriate surgery. Vitreous entanglement occurred in six eyes, and vitreous herniation after PPCCC over-sizing in two. In three, anterior vitrectomy was performed. There was only one single case of retinal detachment-supposedly unrelated to the technique itself-and no case of cystoid macular edema. Retro-optical regenerate formation was completely abolished, while fibrosis was drastically reduced by the posterior capsule sandwiched in between the anterior LEC layer on the backside of the anterior capsule and the anterior optic surface, thereby blocking contact-mediated myofibroblastic LEC transdifferentiation. Additional capsular polishing further reduced residual fibrosis emerging from the anterior capsule contacting the optic adjacent to the haptic junction, as well as regeneratory LEC re-proliferation on the posterior capsule overlying the optic. Postoperative pressure course was almost identical to that found after standard in-the-bag implantation of the IOL, as was flare, and macular thickness and morphology. As opposed to bag-fixated IOLs, no axial movement of the optic was detected. IOL optics always perfectly centered even when the capsular opening was not optimally centered. Due to the exquisite stretchability and elasticity of the posterior capsule, the 6-mm IOL optic could safely be buttoned-in in a posterior capsulorhexis of 4 mm and smaller. CONCLUSIONS: Posterior optic buttonholing (POBH) is a safe and effective technique which not only excludes retro-optical opacification, but also withholds capsular fibrosis by obviating direct contact between the anterior capsular leaf and the optic surface. Anterior LEC abrasion significantly reduced both the residual fibrosis and regeneratory LEC proliferation. Apart from pediatric cataract, POBH is currently recommended for eyes with pseudoexfoliation syndrome, high axial myopia, peripheral retinal disease, and multifocal IOL implantation. Toric IOLs and magnet-driven accommodative IOL systems are other potential applications. Generally, POBH holds promise for becoming a routine alternative to standard in-the-bag IOL implantation in the future.     

Posterior optic buttonholing of intraocular lens implantation through posterior capsulorrhexis margin: A technique of intraocular lens implantation in cases of anterior capsulorrhexis extension in pediatric cataract surgery

This study aimed to evaluate the intra- and postoperative complications of intraocular lens (IOL) implantation with posterior optic buttonholing (POBH) in children that had undergone phacoemulsification irrigation/aspiration for congenital/developmental cataract and experienced complication of anterior capsulorrhexis extension (ACE). A total of 25 eyes of 21 patients were included in the study. A foldable three-piece IOL was implanted into the bag/ciliary sulcus with primary posterior capsulorrhexis and POBH. The visual acuity improved from 2.12 ± 0.69 log MAR to 1.38 ± 0.49 log MAR at 6 months follow-up. Postoperative complications included heightened postoperative inflammation in three patients and temporary corneal edema in two patients. Only one patient had developed posterior capsular opacification (PCO) at 6 months follow-up with mild tilt, while the rest 24 eyes had no PCO formation and adequate IOL centration. The results of this study indicate that a three-piece foldable IOL implantation with POBH is a feasible option for children who experienced ACE during pediatric cataract surgery, as it results in satisfactory surgical outcomes and very few ocular complications.     

人工晶状体植入术后前房深度的变化分析

目的探讨人工晶状体(IOL)植入术后前房深度(ACD)的变化及其相关因素,以获得理想的术后屈光状态。方法收集行白内障超声乳化吸除IOL植入术,术后随访资料完整的117例(177只眼)白内障患者,分析其术后ACD变化及其与眼轴长度、角膜屈光力和IOLA常数的关系。随访时间为3~24个月。结果177只眼IOL植入术前平均ACD为(3.19±0.39)mm,术后平均ACD为(4.22±0.65)mm,两者比较,差异有统计学意义(P=0.000)。177只眼术后ACD的平均变化值为(1.03±0.61)mm;术后ACD的变化值随眼轴长度和角膜屈光力的增加而增大,呈线性正相关(r=0.866,0.946;P=0.001)。IOLA常数为118.0、118.4和118.9,3组术前ACD与术后比较,差异均有统计学意义(P<0.01);A常数为118.9组的术后ACD变化值与A常数为118.0和118.4的组比较,差异均有统计学意义(P<0.05);A常数为118.0的组与118.4的组比较,差异无统计学意义(P=0.957)。结论IOL植入术后ACD因眼轴长度、角膜屈光力和IOLA常数等因素的不同而不同程度地增加。在研究IOL屈光度数计算公式的准确性和调整公式的计算值时,应考虑术后ACD的变化及其相关因素。     

Myopic shift from the predicted refraction after sulcus fixation of PMMA posterior chamber intraocular lenses

BACKGROUND: To evaluate the refractive results of sulcus-fixated polymethylmethacrylate (PMMA) posterior chamber intraocular lenses (PC IOLs) after cataract surgery with and without posterior capsule complications. METHODS: The charts of patients who had undergone cataract surgery were reviewed, and eyes that had received sulcus-fixated PMMA PC IOLs were included in the study. Postoperative refraction, predicted postoperative refraction for in-the-bag IOL with the same diopter, intraoperative posterior capsular complications and vitrectomy, axial eye length, incision type (corneal or scleral), and surgery type were recorded and analyzed. The difference between actual postoperative refraction and predicted refraction for the in-the-bag lens was calculated for each patient. RESULTS: Of 143 patients (84 men and 59 women), 162 eyes with a sulcus-fixated posterior chamber intraocular lens were investigated. Mean age was 63.7 +/- 12.1 years. A mean myopic shift of -1.02 +/- 0.96 D from the predicted in-the-bag refraction was found. There were no significant differences between eyes with or without vitreous loss-vitrectomy (p = 0.8), eyes with scleral or corneal incisions (p = 0.11), and eyes having phacoemulsification or extracapsular cataract extraction (p = 0.93). In terms of axial length, there were no significant differences between long, normal, or short eyes (p = 0.85). INTERPRETATION: Sulcus fixation of a PMMA IOL originally planned for in-the-bag fixation caused approximately -1.00 D myopic shift in this study. We recommend that when sulcus fixation is necessary PMMA IOL power should be approximately 1.25 to 1.50 D less than the power for in-the-bag fixation. Axial length, incision type, vitreous loss and use of vitrectomy, and type of the surgery do not appear to alter the postoperative refraction significantly in eyes with sulcus fixation.     

Visual outcomes and complications of posterior chamber intraocular lens implantation in the first year of life

PURPOSE: To document the visual outcome and postoperative complications in infants who had congenital cataract surgery with posterior chamber intraocular lens (PC IOL) implantation in the first year of life. SETTING: The Children's Hospital, Dublin, Ireland. METHODS: Twenty-seven eyes of 20 infants were reviewed. Seven infants (14 eyes) had bilateral congenital cataract and 13 (13 eyes), uniocular cataract. The mean age at surgery was 4 months (range 3 weeks to 11 months). A standard surgical technique involved anterior capsulorhexis, phacoemulsification with or without posterior capsulorhexis with in-the-bag PC IOL implantation, and no anterior vitrectomy. Surgery was performed by 1 surgeon. The mean follow-up was 41 months (range 6 to 88 months). RESULTS: The main complication was lens reproliferation into the visual axis. Of the 11 eyes that did not have a primary posterior capsulorhexis, 10 had 1 or more capsulotomies. Seven required a neodymium:YAG (Nd:YAG) laser capsulotomy a mean of 6 months postoperatively, and 2 had 2 Nd:YAG capsulotomies. Six eyes also had a surgical capsulotomy when the membrane was deemed too thick for further laser treatment. Fourteen of 25 eyes had a primary posterior capsulorhexis; 8 had no further intervention. Four eyes had persistent hyperplastic primary vitreous (PHPV), 3 required a surgical capsulotomy, 2 had an Nd:YAG laser capsulotomy, 2 had an anterior vitrectomy, and 1 developed open-angle glaucoma. There was a mean refractive shift of 6.0 diopters after a mean follow-up of 41 months, with most of the myopic shift occurring in the first 24 months. CONCLUSIONS: Visual axis reopacification was the main complication of IOL implantation in infants, with PHPV leading to more complications and repeat procedures. Anterior vitrectomy appeared to reduce the reoperation rate. Results indicate that primary posterior capsulorhexis is important and Nd:YAG capsulotomy is not satisfactory in infants. In addition, the reduction in glaucoma with IOL implantation, if borne out over the long term, is a significant advantage in cases of congenital cataract.     

Visual function and late complications after cataract surgery by phacoemulsification with primary posterior capsulotomy and intracapsular foldable intraocular lens implantation

PURPOSE: Evaluation of visual function and late complications after cataract phacoemulsification with primary posterior capsulotomy and intracapsular foldable intraocular lens implantation in 22-months follow-up. MATERIAL AND METHODS: Twenty five eyes of 25 patients (mean age: 53 years) were included in the study. All the eyes underwent primary posterior thermal capsulotomy and in-the-bag foldable IOL (Acrysof) implantation. Postoperative visual acuity and complications were analyzed. RESULTS: The best corrected visual acuity 1.0 (Snellen chart) was achieved in 92% (23/25) of the eyes. The most frequent complication was a slight vitreous dislocation to the anterior chamber (4/25 of eyes--16%), resulting in the pupil deformation in two eyes (2/25 of eyes--8%). In one eye (1/25 of eyes--4%) retinal detachment was observed. None of the patients presented CME. CONCLUSIONS: A very good visual function and low rate of serious late complications suggest, that cataract phacoemulsification with primary posterior capsulotomy and in-the-bag foldable IOL implantation should be taken into consideration, as an option for preventing PCO. The results of the present study suggest the risk of retinal detachment and CME does not appear, to increase after the primary posterior capsulotomy. However, this conclusion has to be confirmed by randomized studies with longer follow-up period and larger series of patients.     

Long-term complications of bilateral posterior chamber phakic intraocular lens implantation

A 34-year-old woman had posterior chamber phakic intraocular lens (PCP IOL) implantation to correct high myopia in both eyes. Five years postoperatively, the patient presented with a decrease in visual acuity from central anterior subcapsular cataract formation in both eyes and IOL dislocation in the left eye. In vivo confocal microscopy of the cornea showed markedly decreased endothelial cell density in both eyes and the presence of bright endothelial microdeposits possibly related to pigmentary dispersion. Gonioscopy showed angle pigmentary deposits with no intraocular pressure increase. The patient was successfully treated by removing the PCP IOLs and performing phacoemulsification with in-the-bag IOL implantation in both eyes. This led to a recovery of visual acuity. This case report presents the rare occurrence and surgical management of cataract formation, IOL dislocation, and severe endothelial cell loss as a late complication of PCP IOL implantation.     

Macular morphology after cataract surgery with primary posterior capsulorhexis and posterior optic buttonholing

PURPOSE: To evaluate possible changes in macular morphology after cataract surgery with combined primary posterior capsulorhexis and posterior optic buttonholing in comparison to conventional in-the-bag intraocular lens (IOL) implantation. DESIGN: Prospective randomized study. METHODS: Fifty consecutive age-related cataract patients with normal macular morphology and function waiting for bilateral cataract surgery were enrolled. Cataract surgery with combined primary posterior capsulorhexis and posterior optic buttonholing was performed in one eye; in the fellow eye cataract surgery was performed with in-the-bag IOL implantation, leaving the posterior lens capsule untouched. Optical coherence tomography measurements were performed one week and one month postoperatively. RESULTS: During follow-up, no statistically significant changes of macular morphology could be observed in any of the tested patients. Mean central retinal thickness, minimum and maximum retinal thickness, and central retinal volume were all statistically comparable between the eyes with combined primary posterior capsulorhexis and posterior optic buttonholing and the control eyes (P > .05). Best-corrected visual acuity was full in all patients (Snellen 20/25 and better). No cases of subclinical macular edema were observed. CONCLUSION: Cataract surgery with combined primary posterior capsulorhexis and posterior optic buttonholing apparently does not increase the risk for postoperative macular edema in patients with a normal macula, since no cases of biomicroscopically noticeable macular edema with visual loss were observed in the first 1,000 eyes with primary posterior capsulorhexis/posterior optic buttonholing cataract surgery and no case of subclinical macular edema was found in this prospective randomized study.     

超声乳化术中人工晶状体前囊夹持植入的临床观察

目的:观察超声乳化术中人工晶状体前囊夹持植入法的临床效果。方法:对白内障超声乳化术中撕囊口过小21例21眼、后囊破裂6例6眼、囊袋宽松1例2眼采用前囊夹持法植入后房型人工晶状体,术后观察视力、人工晶状体位置及后发性白内障情况,术后随访6～24mo。结果:术后3mo视力0.3以上6眼,0.5以上13眼,0.8以上10眼,人工晶状体位置稳定,后发性白内障发生率与囊袋内植入相近,未发现其它与固定有关的并发症。结论:白内障超声乳化术中采用前囊夹持法植入后房型人工晶状体效果良好,是超声乳化术中出现撕囊口过小、后囊膜破裂等并发症的一种有效补充手段。     

Intraoperative management of posterior capsule tears in phacoemulsification and intraocular lens implantation

OBJECTIVE: This paper presents the incidence, causes, and management of posterior capsule (PC) tears and their postoperative outcomes in a large series of eyes that underwent cataract removal and intraocular lens (IOL) implantation, operated on by one surgeon. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Eighteen thousand four hundred seventy consecutive eyes (1992-1999) were reviewed with the assistance of electronic medical records for incidence of PC tears in patients seeking treatment at an outpatient cataract surgery clinic. INTERVENTION: Eyes in this series underwent continuous curvilinear capsulorrhexis (CCC), nucleofractis phacoemulsification, and IOL implantation under topical anesthesia. Different intraoperative surgical strategies such as posterior continuous curvilinear capsulorrhexis (PCCC) were used in the management of PC tears. MAIN OUTCOME MEASURES: Routine preoperative and postoperative visual and refractive outcomes were recorded, including incidence of lens capsule tears, IOL position, and postoperative complications. RESULTS: Posterior capsule tears occurred in 83 of 18,470 eyes, resulting in an overall incidence of 0.45%. Of these 83 eyes with PC tears, 49% received vitrectomy. Fifty-one of 83 PC tears (61.4%) were amenable to be converted to PCCC. Of these 51 procedures, 50 eyes had PC IOL in-the-bag fixation. One eye had PCCC with optic capture. There were no eyes with dropped nuclei or nuclear fragments requiring pars plana vitrectomy. Seventeen eyes (20.5%) had Neuhann anterior capsule rhexis fixation with the haptics placed in the sulcus and IOL securely in the bag. Ten eyes (12.1%) had the IOL placed in the sulcus, and 5 eyes (6.0%) required anterior chamber IOL fixation. None of the 83 PC tears resulted in clinically evident cystoid macular edema, retinal detachment, or endophthalmitis. CONCLUSIONS: With an intact CCC and with conversion of PC tears to PCCC, in-the-bag fixation of IOLs can be achieved in most eyes.     

Nucleofractis phacoemulsification through a small pupil.

A small pupil is an added risk with any technique for cataract extraction. A prospective study involving 1880 consecutive cataract procedures performed by one surgeon between January and June 1990 was carried out to determine the incidence of small pupils (preoperative diameter of 4 mm or less) and the surgical risk with phacoemulsification and implantation of an intraocular lens (IOL) "in the bag." Thirty eyes (1.6%) were found to have a small pupil. All 30 eyes received an in-the-bag posterior chamber IOL, with no intraoperative complications such as anterior or posterior capsule tears. The need for iris-enlarging surgery was correlated with pupil size: such surgery was done in O of the 10 eyes with pupils measuring 4 mm, 1 of the 12 eyes with pupils measuring 3 to 3.5 mm and 4 of the 8 eyes with pupils measuring 2 to 2.5 mm. The author proposes that opening the capsule with a continuous tear and removing the cataract by means of phacoemulsification with nuclear fracturing (nucleofractis) constitutes safe, efficient surgical management of eyes with small pupils undergoing cataract extraction.     

Phacoemulsification combined with posterior capsulorhexis and anterior vitrectomy in the management of malignant glaucoma in phakic eyes

Purpose: To describe sequential phacoemulsification–intraocular lens (IOL) implantation–posterior capsulorhexis–anterior vitrectomy in the management of phakic malignant glaucoma. Methods: Twenty consecutive patients (25 eyes) with phakic malignant glaucoma were enrolled at the Zhongshan Ophthalmic Center, Sun Yat‐sen University. All patients underwent phacoemulsification, IOL implantation and posterior capsulorhexis together with anterior vitrectomy via a clear corneal paracentesis. Visual acuity, intraocular pressure (IOP), anterior chamber depth (ACD), surgical complications and medications required after the surgery were recorded. Results: After surgery, the mean LogMAR visual acuity and ACD increased significantly (visual acuity from ?1.56 ± 1.17 to ?0.54 ± 0.81, p < 0.001; ACD from 0.367 ± 0.397 mm to 2.390 ± 0.575 mm, p < 0.001), and mean IOP decreased significantly (from 39.6 ± 10.6 mm Hg to 14.5 ± 4.1 mmHg, p < 0.001). No serious perioperative complications occurred, and only five eyes required topical glaucoma medications after surgery. Conclusion: Combined phacoemulsification–IOL implantation–posterior capsulorhexis–anterior vitrectomy surgery is a safe and effective method for treating patients with phakic malignant glaucoma.     

超声乳化白内障摘除术中后囊破裂的Ⅰ期后房型人工晶体植入术

目的评价超声乳化白内障摘除术中后囊破裂的Ⅰ期后房型人工晶体植入术的疗效。方法对１８４例（２００只眼）施行超声乳化白内障摘除术中后囊破裂者２９例（２９只眼）行Ⅰ期后房型人工晶体植入术。结果１０例囊袋内植入,１９例睫状沟植入。术后３个月随访,裸眼视力１．０以上者１７例（５８．６２％）,０．５～０．９者１０例（３４．４８％）;矫正视力１．０以上者２２例（７５．８６％）,０．５～０．９者５例（１７．２４％）。本组并发症主要为角膜水肿,瞳孔缘虹膜咬伤,前段玻璃体炎症等。结论对于后囊破裂及玻璃体脱出的患者,适当利用残留的前、后囊作为支撑,清除前段玻璃体,仍可植入后房型人工晶体。     

Effect of in-the-bag intraocular lens fixation on the prevention of posterior capsule opacification

PURPOSE: To compare the incidence of posterior capsule opacification (PCO) after extracapsular cataract extraction (ECCE) and phacoemulsification and to evaluate the role of posterior chamber intraocular lens (PC IOL) haptic fixation and biomaterial/design in reducing the incidence. SETTING: Postgraduate Institute of Medical Education and Research, Chandigarh, India; Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: This study comprised 278 eyes of 263 patients having ECCE and 318 eyes of 297 patients having phacoemulsification with PC IOL implantation. Posterior capsule opacification leading to a decrease in Snellen visual acuity of 2 or more lines was considered visually significant. The presence of PCO and IOL haptic fixation were evaluated postoperatively using slitlamp biomicroscopy. Haptic position was noted as in-the-bag (B-B), 1 haptic in the bag and 1 in the sulcus (bag-sulcus [B-S]), or both haptics out of the bag (sulcus-sulcus [S-S]). In addition, the rate of visually significant PCO was compared among 3 IOL biomaterials: poly(methyl methacrylate), silicone, and hydrophobic acrylic.Results: Visually significant PCO occurred in 42.45% of eyes having ECCE and 19.18% of eyes having phacoemulsification (P <.001, chi-square test) after a mean follow-up of 2.4 years +/- 0.7 (SD). In both groups, visually significant PCO was significantly less in eyes with B-B fixation than in those with B-S or S-S fixation (P <.001). The rate of visually significant PCO in all eyes in the phacoemulsification group with B-B fixation was low (11.90%) and was significantly lower in eyes with a hydrophobic acrylic IOL (2.22%; P <.05, chi-square test). CONCLUSIONS: In-the-bag PC IOL fixation is required to consistently reduce the incidence of PCO. Thorough removal of lens substance, including hydrodissection-assisted cortical cleanup, and in-the-bag PC IOL fixation seem to be the most important factors in reducing PCO, regardless of surgical procedure or IOL type used. Intraocular lens biomaterial and design also help prevent PCO.     

Comparison of epilenticular IOL implantation vs technique of anterior and primary posterior capsulorhexis with anterior vitrectomy in paediatric cataract surgery

PURPOSE: To compare the functional outcome of epilenticular intraocular lens (IOL) implantation vs the technique of anterior continuous curvilinear capsulorhexis (ACCC), posterior continuous curvilinear capsulorhexis (PCCC) with vitrectomy and in-the-bag IOL implantation in paediatric cataract surgery. METHODS: Forty eyes of 33 children with developmental or traumatic cataract, whose mean age was 2-12 years, were randomly divided into two groups A and B. Group A patients underwent epilenticular IOL implantation while in group B patients, ACCC, PCCC with anterior vitrectomy with in-the-bag IOL implantation was performed. Equal number of eyes (10 each) with developmental cataracts (subgroups A1 and B1) and traumatic cataracts (subgroups A2 and B2) were allotted to both the groups. Postoperative visual acuity, opacification of the visual axis, and possible complications were observed and analysed. RESULTS: Four eyes in subgroup B2 had fibrous or ruptured capsules, and were managed by epilenticular IOL implantation technique. One eye in subgroup B2 developed central posterior capsular opacification and hence required a secondary capsulotomy. All cases in group A maintained a clear visual axis at the last follow-up. Minimal postoperative inflammation was noticed in all groups, which subsided with anti-inflammatory medication. At the last follow-up, all eyes in group A gained visual acuity >/=6/18. Whereas in group B, visual acuity >/=6/18 was obtained in 85.7% cases with the epilenticular IOL implantation technique and in 83.3% cases with ACCC and PCCC with anterior vitrectomy technique. CONCLUSION: Epilenticular IOL implantation offers a safe and effective alternative for management of paediatric cataract. In selected cases of traumatic cataract, it is the preferred treatment modality.     

高度近视合并白内障植入不同后房型人工晶状体对眼内轴向结构稳定的影响

目的观察高度近视合并白内障植入不同后房型人工晶状体对眼内轴向空间结构稳定的影响,为此类患者选取最佳的人工晶状体提供临床依据。方法对高近视合并白内障患者128例（142只眼）施行自内障超声乳化吸出联合人工晶状体植入术,根据植入的人工晶状体不同分为三组：Bigbag组50只眼、Semar组46只眼,PM-MA组46只眼。观察三组患者术后1个月的最佳矫正视力,术后第1个月角膜内皮到后囊膜面的距离与术前中央前房深度的差值,术后并发症等指标。结果所有手术眼术后矫正视力均有不同程度提高,Bigbag组术后1个月角膜内皮到后囊膜面的距离与术前的前房深度差值显著大于Sensar组和PMMA组,组间比较差异均有统计学意义（P〈0．05）,三组术后均未见严重并发症。结论超声乳化吸出联合Bigbag人工晶状体植入术可以有效改善高度近视白内障患者的视力,对后囊膜起到稳定的支撑作用,有利于眼内轴向空间结构的稳定,减轻手术对眼后段的影响。     

Pseudo-accommodation with intraocular lenses implanted in the bag

PURPOSE: To evaluate the accommodation potential in eyes after intraocular lens in-the-bag implantation. METHODS: Fifty-one consecutive patients were included in the study. Group 1 included 26 eyes that had phacoemulsification with continuous curvilinear capsulorhexis and in-the-bag implanted foldable IOL. Twenty-five eyes in Group 2 had capsulotomy with extracapsular cataract extraction and were implanted with polymethylmethacrylate IOL. Time elapsed from surgery was at least 6 months. There was no significant difference for age or gender between groups (P > .05). We measured accommodation amplitude and depth of the anterior chamber at distance and near fixation with an ultrasonic biometry device. The results were compared using the unpaired Student t-test. RESULTS: The anterior chamber depths while fixating at a distant object were not significantly different between groups (P>.05), however, at near the difference was statistically significant (P=.008). The change in depths between far and near fixation was significantly different (P=.002) and was more pronounced in the the capsulorhexis group (P < .001). The accommodation amplitudes in this group were significantly greater than in the capsulotomy group (P = .025). CONCLUSION: Patients who had uncomplicated small incision phacoemulsification surgery with continuous curvilinear capsulorhexis and in-the-bag implanted lens seemed to preserve some pseudo-accommodation after surgery.