Staining the Anterior Capsule with Indocyanine Green or Trypan Blue for Capsulorhexis in Eyes with White Cataract

Aim: To assess the efficacy and safety of indocyanine green (ICG) 0.5% and trypan blue 0.1% for anterior capsule staining in cases of white cataract. Methods: This prospective study comprised 55 eyes of 55 patients with white cataract that had phacoemulsification with foldable intraocular lens implantation. ICG in 30 eyes and trypan blue in 25 eyes were used under air to stain the anterior lens capsule. The staining patterns and the ease of creating a continuous curvilinear capsulorhexis (CCC) were assessed; the intraoperative and postoperative complications were noted. The mean follow-up was 17.68±1.65 months. Result: Either ICG or trypan blue stained the anterior capsule uniformly. However, the staining provided by trypan blue was slightly superior. A CCC was successfully achieved in 25 eyes (100%) with trypan blue, and 29 eyes (96.7%) with ICG, respectively. There was no significant postoperative reaction in any eye. Conclusion: The use of vital dyes such as ICG and trypan blue guarantees a complete CCC and makes it possible to deliver the benefits of phacoemulsification in the patients with white cataract.     

Anterior capsule staining for capsulorhexis in cases of white cataract: comparative clinical study

PURPOSE: To compare the safety and efficacy of trypan blue 0.1%, gentian violet 0.001%, indocyanine green 0.5% (ICG), fluorescein 2%, and the patient's autologous blood for anterior capsule staining in cases of white cataract. SETTING: Rajendra Prasad Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. METHODS: Fifty eyes of 50 patients with age-related white cataract had anterior capsule staining with trypan blue, ICG, or gentian violet under an air bubble or subcapsularly with fluorescein or autologous blood followed by phacoemulsification with foldable intraocular lens implantation. Each stain was used in 10 eyes. The ease of creating a continuous curvilinear capsulorhexis (CCC) and the complications during the surgery were noted. Postoperative examinations at 6 hours, 1 day, 1 week, and 1 month included slitlamp microscopy, uncorrected visual acuity, and best corrected visual acuity (BCVA). The staining patterns on the anterior capsule, side port, corneal tunnel, and anterior cortex were assessed intraoperatively and within 6 hours and at 1 day. The intraocular pressure (IOP) was assessed at 1 day; pachymetry, at 1 day and 1 month; and the endothelial cell count, at 1 month. RESULTS: The surgeon had best visualization during the anterior capsulorhexis with trypan blue, ICG, and gentian violet, and a complete CCC was achieved in all eyes in the 3 groups. Two eyes each in the fluorescein and autologous blood groups had extension of the CCC so that the capsulorhexis was complete but not curvilinear. Anterior capsule fibrosis was detected with trypan blue (1 eye) and ICG (2 eyes). The anterior vitreous was stained with fluorescein in 2 eyes. All eyes achieved a BCVA of 20/30 or better from 1 week postoperatively to the last follow-up. The side port and corneal tunnel were stained most intensely with gentian violet followed by trypan blue and ICG and less intensely with fluorescein and autologous blood. The IOP, pachymetry, and endothelial cell loss were comparable between the stains. CONCLUSION: Although trypan blue, ICG, gentian violet, fluorescein, and autologous blood were safely used to stain the anterior capsule for phacoemulsification in eyes with white cataract, trypan blue, ICG, and gentian violet were more effective in staining the capsule.     

台盼蓝在白色白内障超声乳化术中的应用

目的 探讨台盼蓝对晶状体前囊染色在白色白内障手术中应用效果。方法82例87眼随机分为染色组43例46眼与对照组39例41眼，染色组术中用台盼蓝染色，观察前囊膜着色效果、撕囊成功率、在超声乳化术中囊膜保护的完整率以及术中、术后并发症等，并与对照组进行统计学分析。结果染色组前囊膜均均匀着色，撕囊成功率与术中囊膜完整率均为100％，与对照组比较有明显统计学差异；术后视力、眼压、炎症反应、角膜内皮水肿与对照组比较无统计学差异。结论台盼蓝染色是一种简单安全的晶状体前囊膜染色技术，提高了前囊膜的可见度，有助于白色白内障超声乳化术连续环形撕囊术(continuous curvilinear capsulorhexis,COC)和整个手术的顺利进行。     

生物活性染色剂在白色白内障撕囊术中的应用

目的 评价生物活性染色剂在白色白内障超声乳化手术中显现晶状体前囊的可行性和安全性等。方法 55例白色白内障随机编人台盼蓝和吲哚青绿前囊染色组。采用气泡下染色技术完成连续环形撕囊。结果 台盼蓝和吲哚青绿均可充分着染前囊。染色辅助撕囊的总成功率为98．2％。吲哚青绿组和台盼蓝组分别为96．7％、100％。尚未观察到术后染色剂残存于眼组织或人工晶状体异色。术后矫正视力0．5～1．2。结论 生物活性染色剂可显著提高白色白内障超声乳化手术的安全性。     

台盼蓝囊膜染色剂在白内障连续环形撕囊手术中的应用

目的研究台盼蓝囊膜染色剂在治疗白色白内障中,是否有助于连续环形撕囊的顺利完成及白内障手术的顺利进行。方法79例(80眼),随机分为2组,染色组40例(41眼),对照组39例(39眼),染色组使用台盼蓝囊膜染色剂,术中观察及对比前囊膜染色情况、连续环性撕囊成功率、晶状体后囊破裂及人工晶状体囊袋内植入情况,术后视力、前房炎症反应、角膜、人工晶状体有无蓝染及后囊混浊情况。并与对照组进行统计学分析。结果染色组的术中染色均匀,连续环形撕囊及人工晶状体囊袋内植入率为97.7%,晶状体后囊破裂率为2.44%,与对照组进行统计学分析有显著差异。术后追踪观察3个月,染色组术后视力好于对照组,前房炎症反应、晶状体后囊混浊2组无统计学差异。染色组术后角膜、人工晶状体未见蓝染,未见术中及术后并发症。结论台盼蓝囊膜染色剂目前是一种安全可靠的技术,手术中可以看清前囊,使连续环形撕囊顺利进行,人工晶状体稳定的位于囊袋内,增加了白色白内障手术的成功率。     

白色白内障撕囊丢失囊膜台盼蓝染色的有效性探讨

目的 探讨成熟期和过熟期白色白内障连续环形撕囊(CCC)囊膜丢失后,在不吸除黏弹剂情况下使用台盼蓝染色找回丢失囊膜的有效性.方法 对52例(52只眼)术中连续环形撕囊发生囊膜丢失的连续性白色白内障病例进行前瞻性研究.随机分为两组,染色组27例(27只眼),对照组25例(25只眼).染色组不吸除前房玻璃酸钠,使用台盼蓝囊膜染色.对照组吸除前房玻璃酸钠后进行撕囊或截囊.对两组连续环性撕囊成功率、人工晶状体囊袋内植入率进行统计学分析.结果 染色组连续环形撕囊及人工晶状体囊袋内植入率高于对照组,差异具有统计学意义(P<0.01),无毒性及并发症发生.对照组有9只眼人工晶状体植入睫状沟,6只眼发生后囊膜破裂及玻璃体脱出.结论 在连续环形撕囊发生囊膜丢失后,采取不吸除前房黏弹剂,应用台盼蓝对晶状体前囊膜染色,对找回丢失囊膜和CCC继续完成是有效和安全的.     

Trypan-blue- and endoillumination-assisted phacoemulsification in eyes with vitreous hemorrhage during combined cataract and vitreous surgery

PURPOSE: To study the safety and usefulness of trypan blue application and conventional endoillumination for enhancing visualization during phacoemulsification and foldable intraocular lens implantation in cases of cataract with vitreous hemorrhage. METHODS: Ten eyes of 10 patients with cataract and coexisting vitreous hemorrhage underwent combined trypan-blue- and endoillumination-assisted phacoemulsification and foldable intraocular lens implantation with vitrectomy. In a two-step surgery, after staining the anterior capsule with trypan blue, continuous circular capsulorhexis was performed; then, phacoemulsification was performed using conventional endoillumination. Specular microscopy was performed before and 3 months after surgery on eyes that underwent trypan-blue- and endoillumination-assisted phacoemulsification and on control eyes that underwent standard phacoemulsification to evaluate the toxic effect of trypan blue on corneal endothelial cells. RESULTS: Trypan blue application improved visualization of the anterior capsule, and a complete capsulorhexis could be performed in all eyes. In all 10 eyes, endoillumination was required to visualize the lens structure, and phacoemulsification could be accomplished. Specular microscopy revealed that there was no significant difference in the level of corneal endothelial cell loss between the trypan-blue- and endoillumination-assisted phacoemulsification group and the control group. CONCLUSION: The described double visualization technique may assist phacoemulsification in selected cases of cataract with vitreous hemorrhage.     

台盼蓝在成熟期白内障超声乳化术中的应用

目的探讨台盼蓝着色前囊膜在成熟白内障超声乳化手术中的应用。方法本组32例老年性白内障成熟期、过熟期患者接受台盼蓝前囊膜染色,采用前房气泡下染色法,前房注入0.1mL染色液,数秒钟后用BSS液冲洗置换染液及气泡,注入粘弹剂后,连续环行撕囊。对照组取同期白内障超声乳化患者30例,比较环行撕囊成功率、术后视力、眼压及角膜水肿程度。结果经染色后32例前囊膜均呈淡蓝色,清晰可辨,撕囊成功率达97%,而对照组为80%,有显著差异。术后视力、眼压及角膜内皮水肿无显著差异。结论台盼蓝着色前囊膜后,连续环行撕囊更安全易行。     

低浓度台盼蓝囊膜染色技术在白内障手术中的应用

目的：探讨台盼蓝染色晶状体前囊膜的最低有效浓度,评价白内障手术中应用囊膜染色技术的临床意义。

方法：收集2014-03/2016-12成熟期年龄相关性白内障患者60例60眼,晶状体皮质混浊程度为C4～C5、核混浊程度为N3(以晶状体混浊分类系统Ⅱ为标准),随机分为三组。三组患者术中分别使用0.03%、0.015%和0.0075%三种不同浓度台盼蓝。所有患者均由同一经验丰富手术医生完成手法小切口白内障手术。术中观察前囊膜染色情况以及撕囊难易程度。记录连续环形撕囊术(continuous circular capsulorhexis,CCC)成功、后囊袋破裂以及人工晶状体囊袋内植入情况。观察术后1d,1wk,3mo术眼角膜内皮细胞计数、眼压、前房炎症反应、角膜水肿和眼内结构染色情况。

结果：浓度低至0.015%的台盼蓝仍可对晶状体前囊膜有效染色,顺利完成CCC。0.03%与0.015%两组患者CCC成功率和IOL囊袋内植入率均高于0.0075%组,差异均有统计学意义(P<0.0083)。三组患者后囊破裂发生率和角膜内皮细胞平均损失率两两比较,差异均无统计学意义(P>0.0083)。术后晶状体前囊撕囊口边缘及侧切口的着染均于1wk内消失,未见其他眼内结构蓝染,前房炎症反应轻,未发现超过1wk的角膜水肿和眼压升高。

结论：白内障手术中应用台盼蓝晶状体前囊膜染色技术安全有效,可提高手术成功率,建议使用台盼蓝最低有效浓度为0.015%。     

针头抽吸方法在白色膨胀白内障撕囊术中的应用

目的：探讨针头抽吸方法在白色膨胀白内障撕囊术中的临床疗效。

方法：应用针头抽吸方法后连续环形撕囊(CCC)治疗白色膨胀白内障166眼。15°穿刺刀在3：00位作辅助切口,注入带有灭菌空气的台盼蓝染色剂约0.1mL进行前囊膜染色,向前房内注入透明质酸钠,再用3.2mm穿刺刀作上方角膜缘切口,保持主切口偏小,然后用一个1mL带27G针头,斜面朝上,穿刺前囊膜抽吸液化皮质,斜面侧向旋转不扩大前部的穿刺口,轻轻压迫晶状体核,继续将前移的核后部的液化皮质吸走,用足够的黏弹剂填充前房,随后用3.2mm穿刺刀扩大角膜切口,完成CCC。

结果：白色膨胀白内障166眼应用此方法,155眼成功完成了环形撕囊,成功率93.4%。

结论：白色膨胀白内障超声乳化手术撕囊过程中,应用针头抽吸方法,通过吸走足够的液化皮质,清除部分膨胀晶状体,不但减轻了晶状体和囊袋的压力,从而可达到环形撕囊的目的,而且减少了因前囊膜不完整带来的手术操作不便和并发症,是一种安全、简便、有效的操作方法,便于掌握和应用。     

白内障撕囊直径不同对后发性白内障影响的临床研究

目的:观察连续环形撕囊口完全覆盖人工晶状体光学面与连续环形撕囊口完全不覆盖人工晶状体光学面的人工晶状体植入术后后囊膜混浊(posterior capsular opacification,PCO)的情况。方法:随访近5a来施行超声乳化吸出白内障联合人工晶状体植入手术的老年性白内障患者164例196眼,术后观察视力、撕囊口与人工晶状体光学面的关系及PCO等情况,随访12~26(平均16.3)mo。根据Sellman等的PCO分级标准进行分级:I级为没有PCO或极轻微PCO不减少红光反射,也没有珍珠样小体或IOL边缘也没有发现珍珠样小体;Ⅱ级为轻度PCO减少了红光反射,IOL边缘也没有发现珍珠样小体;Ⅲ级为在IOL区域内发现中度纤维化或珍珠样小体,但视轴(中心3mm)是透明的;Ⅳ级为重度纤维化或珍珠样小体并扩展到视轴区,并且严重减少红光反射。术后后囊膜出现Ⅱ,Ⅲ及Ⅳ级统计为临床出现后发性白内障的并发症病例。结果:后发性白内障是现代白内障摘除手术后晚期常见的并发症之一,连续环形撕囊口完全覆盖人工晶状体光学面组120眼中,发生后发性白内障42眼(35.0%)。连续环形撕囊口完全不覆盖人工晶状体光学面组76眼中,发生后发性白内障41眼(53.9%)。两组病例术后在临床后发性白内障发生率上有统计意义(P<0.05)。结论:连续环形撕囊口大小与术后后囊膜的混浊有关。撕囊口完全覆盖人工晶状体光学面能减少后发性白内障发生的几率。     

Trypan blue assisted phacoemulsification in corneal opacities

AIM: To evaluate the efficacy of trypan blue for enhancing visualisation during phacoemulsification and foldable lens implantation in cases of cataract with corneal opacities. METHODS: 11 eyes of 11 patients with nebulomacular corneal opacities involving the visual axis with partially and visually debilitating cataract underwent trypan blue assisted phacoemulsification with foldable intraocular lens implantation. The patients were followed at the first day, first week, first month, and third month postoperatively. Completion of capsulorhexis, phacoemulsification with foldable lens implantation, and postoperative best corrected visual acuity were measured. RESULTS: The dye improved visualisation of the anterior capsule and a complete capsulorhexis could be performed successfully in all eyes. In all but one eye phacoemulsification was accomplished successfully. In one eye with Fuchs' dystrophy penetrating keratoplasty was performed later. Visual acuity was < or = 6/60 preoperatively in all eyes and improved to > or = 6/24 in eight eyes postoperatively. CONCLUSION: Trypan blue assisted phacoemulsification may be performed in selected cases of corneal haze/opacification with cataract. It provides acceptable visual outcome in cases awaiting penetrating keratoplasty or in cases where it is not feasible or promising.     

晶状体前囊膜苔盼蓝染色在白内障超声乳化术中的临床应用观察

目的 探讨晶状体前囊膜染色技术在白内障超声乳化术中应用的有效性和安全性。方法 88例（90只眼）行白内障超声乳化术患者,分成染色剂辅助撕囊组A组40例（40只眼）,和常规手法撕囊组B组40例（40只眼）,观察撕囊成功率、在超声乳化手术中囊膜保护完整率以及眼压和房水炎症反应等。结果 连续环形撕囊成功者,A组为95％（38／40）,B组为62．50％（25／40）;A、B两组中,分别有2只眼及10只眼出现前囊膜向赤道部撕裂,并行前段玻璃体切割术。结论 染色剂辅助撕囊技术,对于一些缺乏眼底红光反射的白内障患者,可以明显提高连续环形撕囊的成功率,使这类患者的超声乳化术更加安全。     

囊袋张力环在白内障手术中的应用

目的:评价半脱位晶状体超声乳化术中植入囊袋张力环(CTR)的应用效果。方法:对12例12眼半脱位晶状体行白内障手术,术中连续环形撕囊,行白内障晶状体超声乳化术,植入CTR后,囊袋内植入折叠式人工晶状体。结果:晶状体半脱位白内障患者12眼均顺利植入了CTR及后房型人工晶状体。术后患者视力均得以提高,人工晶状体位正,无明显手术并发症。结论:CTR可防止人工晶状体偏位,减少手术并发症。     

Phacoemulsification of white hypermature cataract.

PURPOSE: To evaluate the safety of phacoemulsification of white hypermature cataract, which is common in developing countries. SETTING: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. METHODS: In a teaching hospital setting, a prospective evaluation of phacoemulsification in 25 eyes of 25 consecutive patients with hypermature cataract was done. Patients with good pupil dilation, optimal endothelial cell count, and disease-free ocular and systemic status were included. High magnification, sodium hyaluronate, and a Utrata capsulorhexis forceps were used to perform continuous curvilinear capsulorhexis (CCC). The stop and chop technique was used for nuclear emulsification. A 5.5 mm optic allpoly(methyl methacrylate) intraocular lens (IOL) was implanted, and wound closure was sutureless. RESULTS: Successful CCC was performed in 23 of 25 cases. In 2 cases, the CCC edge extended toward the periphery and a Vannas scissors was used to achieve an even cut. No complications were seen during nuclear emulsification and IOL implantation. Eighty percent of the patients had a visual acuity of 20/40 or better on the first postoperative day. Five patients had significant corneal edema that resolved within 1 week in all cases. CONCLUSION: Phacoemulsification was successfully and safely performed in appropriately selected patients with white hypermature cataract.     

超高度近视白内障不同撕囊口直径下术后人工晶状体稳定性观察

目的：：比较超高度近视白内障患者不同撕囊口直径下行超声乳化人工晶状体植入术后的人工晶状体囊袋内稳定性差异。方法：选择双眼超高度近视拟行白内障患者14例,双眼先后均行Phaco+IOL植入术,随机选择一眼作为5 mm撕囊口直径观察组,对侧眼作为6 mm撕囊口直径观察组,娴熟手术医师完成白内障摘除联合囊袋内人工晶状体植入同型亲水丙烯酸非球面人工晶状体( MCX11),手术经过均顺利,所有入组患者术后次日经Image-pro plus6.0图像分析软件测量确认主要子午线囊口直径与目标撕囊直径不超过±0.2mm。术后1wk;1,3,6mo行散瞳后囊口形态、人工晶状体位置形态观察,屈光状态检查,前房深度测量,观察囊袋内人工晶状体的稳定性。结果：与术后1 wk相比,两组术后1 mo前囊口直径轻度缩小,两组间无显著差异。5 mm组在1~3 mo随访期内有轻度远视漂移,6mm组在术后1mo内有轻度远视漂移,1mo后则趋于稳定。屈光变化与前房深度变化同步。5 mm组3 mo随访期有3眼发生襻缘轻度变形。结论：超高度近视患者采用较小的撕囊口可能引起囊袋-IOL复合体的不均匀收缩或前后移位。术后1 mo屈光状态的进行性变化可早期提示人工晶状体稳定性的变化,及时进行干预可减少远期并发症的发生。     

Achieving successful capsulorhexis in intumescent white mature cataracts to prevent Argentinian flag sign - A new multifaceted approach to meet the challenge

Purpose:To present a case series of intumescent white cataract cases managed by a new surgical technique to attain a single stage Continuous Curvilinear Capsulorhexis (CCC).Methods:The series included 60 eyes of 60 patients with white cataract which underwent preoperative anterior chamber depth, lens thickness and ultrasonographic A-scan for intralenticular spikes. A partial size main port (~1.8mm) is created as the first entry into the anterior chamber (AC). A 30-gauge needle of insulin syringe entered through a limbal stab incision is used to decompress the anterior and posterior intralenticular compartments. Following which a standard size, one stage capsulorhexis was performed in a trypan blue stained capsule using microcapsulorhexis forceps entered through the partial sized trapezoidal main port. The main port was secondarily enlarged for phacoemulsification.Results:Based on the intraoperative findings, 43 eyes were categorized as Intumescent type-1 cataracts i.e., with presence of actual liquefied cortex aspirated using 30-gauge needle and 17 eyes as Intumescent type-2 cataracts, i.e., presence of swollen lens without any obvious liquefied cortex. Standard size, circular and centred CCC was achieved in 100% of the cases and no Argentinean flag sign was noted. Surgeon perceived raised intralenticular pressure in 41% of the cases in type-1 subset and 61% cases in type-2 subset (P-0.06). Posterior capsular plaque was observed in 22% of the cases, adherent cortex in 25% and anterior capsular plaque in 5% of the cases. At 6weeks follow up 92% patients had best corrected visual acuity of 20/40 or better.Conclusion:A multi-layered approach can help in attaining successful CCC in cases of white mature cataract with high intralenticular pressure.     

Manual small incision cataract surgery in eyes with white cataracts

PURPOSE: To assess the safety and efficacy of Manual Small Incision Cataract Surgery (MSICS) in cases of white cataract with the use of trypan blue as an adjunct for performing continuous curvilinear capsulorthexis (CCC). MATERIALS AND METHODS: Prospective observational study on 100 consecutive eyes of 100 patients with white cataract who had undergone MSICS with trypan blue assisted CCC. The nucleus was prolapsed into anterior chamber by using a sinskey hook and extracted out of the eye using irrigating vectis. Intraoperative and postoperative findings (according to OCTET classification) as well as postoperative visual outcomes were used as main measures to report the safety and efficacy of the surgery. RESULTS: Of the 100 eyes, 16 had intumescent, 67 had mature and 17 had hypermature cataract. Intraoperatively CCC was incomplete in 4 eyes (4%) and had to be converted to canopener capsulotomy. None of the eyes had posterior capsular rupture or zonular dialysis and no eyes were converted to conventional Extra Capsular Cataract Extraction (ECCE). Postoperatively, 6 eyes (6%) developed corneal oedema with >10 Descemets folds and 7 eyes (7%) had corneal oedema with CONCLUSION: In developing countries like India where phacoemulsification may not be affordable to a majority of those requiring cataract surgery, MSICS proves to be a safe and efficacious alternative for white cataracts especially with the adjunctive use of trypan blue dye.     

Ultrasound biomicroscopy examination of intraocular lens haptic position after phacoemulsification with continuous curvilinear capsulorhexis and extracapsular cataract extraction with linear capsulotomy.

PURPOSE: Intraocular lens (IOL) haptic position in 35 eyes that had undergone cataract surgery was examined with ultrasound biomicroscopy (UBM). METHODS: In a prospective randomized study the patients were operated by phacoemulsification using continuous curvilinear capsulorhexis (CCC) (group I) or by extracapsular cataract extraction (ECCE) using linear capsulotomy (group II). Ultrasound biomicroscopy was used to localize both haptics of the implanted intraocular lenses and to measure anterior chamber depth (ACD), iris thickness and anterior chamber angle. The inflammatory reaction in the anterior chamber was assessed with laser flare photometry. Slit lamp examination was performed. RESULTS: Both IOL haptics were found in the lens capsule in all 18 eyes in group I. In group II one of the haptics was located out of the capsule in 7 of 17 eyes (41%). The difference is statistically significant (p=0.01). Postoperatively mean ACD measured with the UBM was 4.06+/-0.30 mm in group I and 3.64+/-0.24 mm in group II (p=0.00025). CONCLUSION: The UBM examinations indicate that phacoemulsification with continuous curvilinear capsulorhexis is a more reliable technique than ECCE with linear capsulotomy to achieve implantation of the intraocular lens haptics in the capsular bag.     

白内障二次环形撕囊术

目的 探讨白内障超声乳化吸出术新的撕囊术的临床意义。方法 在315例肿胀白内障的超声乳化吸出术中，采用二次连续环形撕囊术，即先行约4mm的连续环形撕囊，在人工晶状体囊袋骨植入后再次连续环形撕囊，将前囊开口扩大至人工晶状体边缘。术后2周－1年检查眼底并进行相应处理。结果 全部病例在术中未发生前囊开口放射状撕裂。术后检眼镜及荧光素眼底血管造影检查发现74例眼底疾病患者，其中13例接受视网膜激光光疑术治疗。残留的少量前囊对眼底检查和治疗过程影响甚小。结论 在白内障超声乳化吸出术中，对膨胀的白内障采用二次环形撕囊，不但有利于保持晶状体囊袋的完整性和囊口的中心性，也有利于术后眼底疾病的诊治。