爆破超声能量模式在超声乳化白内障吸除术中应用的效果观察

目的探讨爆破超声能量模式在超声乳化白内障吸除术中应用的临床效果。方法将178例(222只眼)白内障患者随机分为连续、脉冲及爆破3组,分别采用连续、脉冲及爆破3种不同超声能量模式行超声乳化白内障吸除人工晶状体植入术。记录并比较3组术中所用的超声能量、有效超声时间及累积复合能量参数(实际超声能量与有效超声时间的乘积),检查术后视力、角膜水肿程度及角膜内皮细胞密度,并观察手术并发症的发生情况。结果爆破组晶状体核硬度Ⅰ或Ⅱ级和≥Ⅲ级者的有效超声时间[(018±003)、(036±025)min]、实际超声能量[(1044±214)%、(2363±371)%]及累积复合能量参数(211±140、694±266)均明显低于连续组和脉冲组,差异均有统计学意义(P<005)。爆破组术后1d和术后3d角膜水肿程度均明显轻于连续组和脉冲组,差异均有统计学意义(P<005)。爆破组术后1周角膜内皮细胞损失率[(1021±887)%]明显低于连续组[(1735±1329)%],差异有统计学意义(P<005)。结论爆破超声能量模式可使超声乳化白内障吸除术的有效超声时间缩短和总体超声能量降低,从而减轻眼内组织损伤,提高手术疗效,值得推广使用。(中华眼科杂志,2005,412730)     

白内障超声乳化吸除术的不同切口对角膜散光的影响

为探讨超声乳化白内障吸除术不同大小切口对术后视力和手术源性角膜散光的影响，对白内障超声乳化３２ｍｍ水平切口、６０ｍｍ反眉状切口的６９只眼对照白内障囊外摘除术１２ｍｍ切口的９６只眼，在术后１周至３个月进行视力和角膜散光的测定和评价。结果：超声乳化３２ｍｍ切口组和６０ｍｍ组术后１周至１个月的视力明显高于囊外摘除１２ｍｍ切口组（Ｐ＜００５），术后１周至３个月时超声乳化组角膜散光明显低于囊外摘除组（Ｐ＜００１）。结论：采用６ｍｍ反眉状巩膜隧道切口水平缝合一针，同样有效减少术后角膜散光并早期获得良好视力，术后１个月时的视力和角膜散光比较３２ｍｍ切口组无明显差异。     

微脉冲超声能量模式在白内障超声乳化吸出术中的应用效果

目的　观察微脉冲超声能量模式在白内障超声乳化吸出术中应用的临床效果。方法　选择2018年9月至2019年2月于我院就诊并行白内障超声乳化吸出联合人工晶状体植入术的患者146例（178眼）进行前瞻性随机对照研究。将患者分为2组,微脉冲模式组（A组,88眼）、脉冲模式组（B组,90眼）。再根据Emery核硬度分级标准将2组患者各分为1（Ⅱ级核,59眼）、2（Ⅲ级核,86眼）、3（Ⅳ级核,33眼）小组。记录术前视力、白内障核硬度分级;比较2组术中所用的实际超声能量（actual power,AP）、有效超声时间(effective phaco time,EPT);术后1 d和7 d最佳矫正视力（best corrected visual acuity,BCVA）;术后1 d、7 d和30 d的中央区角膜内皮细胞密度（corneal endothelial cell density,CECD）、六角形细胞比率和术后30 d的角膜内皮细胞损失率。结果　A组和B组的AP、EPT比较:各组间比较AP均减少、EPT均缩短。A1、B1组比较差异无统计学意义(P＞0.05);A2、B2组及A3、B3组之间比较差异均有统计学意义(均为P＜0.05)。中央区CECD、PHC比较:术后1 d、7 d、30 d分别与术前比较,差异均有统计学意义（均为P＜0.05）。中央区CECD术后不同时间点比较:A1组与B1组差异均无统计学意义（均为P＞0.05）,A2组与B2组、A3组与B3组之间差异均有统计学意义（均为P＜0.05）。术后1 d、7 d A3组与B3组PHC比较差异均有统计学意义（均为P＜0.05）,术后30 d各组间比较差异均无统计学意义（均为P＞0.05）。角膜内皮细胞损失率比较:术后30 d A组与B组差异有统计学意义（P＜0.05）。术后BCVA:术后1 d、7 d A组及B组比较差异有统计学意义(P＜0.05),而术后30 d A、B组差异无统计学意义(P＞0.05)。结论　微脉冲超声能量模式可使白内障超声乳化吸出术的超声时间缩短、超声能量降低,可减少对眼内组织特别是对角膜内皮细胞的损伤,其安全性、有效性值得在临床上推广使用。     

预劈核联合乳化劈核在白内障超声乳化中的应用

目的：比较预劈核联合乳化劈核与拦截劈核两种劈核方式,探讨预劈核联合乳化劈核的技术优点。

方法：将年龄相关性白内障131例156眼随机分为预劈核联合乳化劈核组(A组)68例82眼和拦截劈核组(B组)63例74眼。分别使用预劈核联合乳化劈核和拦截劈核技术进行白内障超声乳化术。记录术中平均超声能量(AP)、实际超声乳化时间(U/S time)、累积能量复合参数(AECP)、平均内皮细胞密度、平均内皮细胞丢失率、术中并发症、术后1d; 1wk裸眼视力和术后1d角膜水肿等情况并进行比较。

结果：将两组中同级核硬度的亚组进行比较,A组的AP,U/S time,AECP均低于B组,差异有显著性; 且前者术后第1d角膜水肿轻于后者。术后1d裸眼视力A组优于B组,术后1wk两组裸眼视力无差异。两组术后3mo平均角膜内皮细胞密度无差异(P>0.05),但两组术后3mo平均角膜内皮细胞丢失率差异有显著性(P< 0.05)。术中出现晶状体后囊膜破裂A组有2眼(2.4%),B组有4眼(5.4%)。

结论：与拦截劈核相比,预劈核联合乳化劈核术中超声时间更短、能量更低、术后3mo角膜内皮细胞丢失率更少、术后早期裸眼视力更好。     

Biaxial microincision cataract surgery versus conventional coaxial cataract surgery: metaanalysis of randomized controlled trials

A comprehensive literature search of Cochrane Library, PubMed, and Embase was performed to identify relevant prospective randomized controlled trials (RCTs) comparing biaxial microincision cataract surgery (MICS) and conventional coaxial phacoemulsification. A metaanalysis was performed on the following outcome measures: effective phacoemulsification time (EPT), phacoemulsification power (%), corrected distance visual acuity (CDVA), surgically induced astigmatism (SIA), laser flare photometry value, percentage of endothelial cell loss, change in central corneal thickness (CCT), and complications. Eleven RCTs describing a total of 1064 eyes were identified. There were no significant differences between the techniques in CDVA, mean percentage of endothelial cell loss, laser flare photometry value, CCT change, and intraoperative and postoperative complications. However, EPT was statistically significantly shorter and the mean phaco power was statistically significantly lower in the biaxial group than in the coaxial group, and biaxial MICS induced less SIA. Financial disclosure: No author has a financial or proprietary interest in any material or method mentioned.     

光学相干断层成像术观察超声乳化白内障吸除术后黄斑变化

目的　探讨超声乳化白内障吸除术后黄斑形态的变化及其可能的影响因素。方法　对行超声乳化白内障吸除术 ,且术前无合并症、术中无并发症发生的单纯老年性白内障患者 80例 (80只眼 )于术前和术后 1周分别行光学相干断层成像术 (opticalcoherencetomography ,OCT)检查 ;按术中使用的超声能量高低分成 2个组。观察黄斑中心凹视网膜厚度的变化及其与术中超声能量、术后前房炎性反应和视力的关系。结果　 80只眼黄斑中心凹视网膜平均厚度术前为 (14 2 9± 16 7) μm ,术后为 (15 7 9± 36 7) μm ,两者比较差异无显著意义 (P >0 0 5 )。术后 3只眼出现黄斑水肿 ,11只眼出现房水中度闪光 ,黄斑中心凹视网膜平均厚度术前为 (139 9± 11 3) μm ,术后为 (197 6± 36 9) μm ,两者比较差异有显著意义 (t =2 75 1,P <0 0 5 )。低能量组术后黄斑中心凹视网膜平均厚度为 (15 6 2± 18 3) μm ,高能量组为 (172 6± 32 9) μm ,两者比较差异有显著意义 (t=2 4 11,P <0 0 5 )。术后最佳矫正视力与黄斑中心凹视网膜厚度呈负相关性 (r=- 0 82 ,P <0 0 5 )。结论　超声乳化白内障吸除术可导致术眼黄斑中心凹视网膜厚度增加及黄斑水肿 ;术中高超声能量可明显影响术后黄斑中心凹视网膜的形态 ;术后黄斑中心     

A prospective randomized clinical trial of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery in Nepal

PURPOSE: To compare the efficacy and visual results of phacoemulsification vs manual sutureless small-incision extracapsular cataract surgery (SICS) for the treatment of cataracts in Nepal. DESIGN: Prospective, randomized comparison of 108 consecutive patients with visually significant cataracts. METHODS: settings: Outreach microsurgical eye clinic. patients: One hundred eight consecutive patients with cataracts were assigned randomly to receive either phacoemulsification or SICS. intervention Cataract surgery with implantation of intraocular lens. main outcome measures: Operative time, surgical complications, uncorrected and best-corrected visual acuity (BCVA), astigmatism, and central corneal thickness (CCT). RESULTS: Both surgical techniques achieved excellent surgical outcomes with low complication rates. On postoperative day 1, the groups had comparable uncorrected visual acuity (UCVA) (P = 0.185) and the SICS group had less corneal edema (P = 0.0039). At six months, 89% of the SICS patients had UCVA of 20/60 or better and 98% had a best-corrected visual acuity (BCVA) of 20/60 or better vs 85% of patients with UCVA of 20/60 or better and 98% of patients with BCVA of 20/60 or better at six months in the phaco group (P = 0.30). Surgical time for SICS was much shorter than that for phacoemulsification (P < .0001). CONCLUSION: Both phacoemulsification and SICS achieved excellent visual outcomes with low complication rates. SICS is significantly faster, less expensive, and less technology dependent than phacoemulsification. SICS may be the more appropriate surgical procedure for the treatment of advanced cataracts in the developing world.     

同轴微切口超声乳化手术对白内障的治疗效果及术后影响

目的：分析同轴微切口超声乳化手术对白内障的治疗效果及术后影响,探讨其临床应用价值。

方法：将300例300眼接受超声乳化手术治疗的白内障患者随机分为观察组和对照组,各150例150眼。观察组患者采用同轴微切口超声乳化手术治疗,对照组患者则采用传统同轴常规切口超声乳化手术治疗。对比分析两组的有效超声乳化时间(effective phaco time,EPT)、平均超声能量(average ultrasound energy,AVE)、术中前房稳定性、术后恢复时间,以及术前和术后1d,1wk,1、3mo时测得的裸眼视力(UCVA)、手术源性角膜散光度数及角膜内皮细胞丢失程度。

结果：两组EPT、AVE及术中前房稳定性均无明显统计学差异(P>0.05)。术前两组UCVA、角膜散光度数及角膜内皮细胞计数均无显著统计学差异(P>0.05)。观察组患者术后恢复时间明显短于对照组,差异有统计学意义(P<0.05)。与对照组比,观察组患者术后1d,1wk,1mo时UCVA均明显较好,差异有统计学意义(P<0.05); 术后1wk,1、3mo时,手术源性角膜散光度数均明显较低,差异有统计学意义(P<0.05); 术后1d,1wk,1、3mo时,角膜内皮细胞丢失率均明显较低,差异有统计学意义(P<0.05)。两组术后各时间点比较,UCVA、手术源性散光度数及角膜内皮细胞丢失率均有显著统计学差异(P<0.05)。

结论：同轴微切口超声乳化术治疗白内障,术后视力恢复快,角膜散光小,角膜内皮细胞丢失程度低,临床应用价值相对较高。     

线性爆破模式在晶状体超声乳化术中的应用

目的 观察线性爆破超声能量模式在晶状体超声乳化吸出术中应用的临床效果.方法 将400例（400眼）白内障随机分为连续、脉冲、爆破及线性爆破模式4组,分别采用连续、脉冲、爆破及线性爆破超声能量模式行超声乳化吸出人工晶状体植入术.术中记录4组使用的实际超声时间,计算累计超声能量（平均超声能量与实际超声时间的乘积）,检查术后视力、角膜内皮细胞密度,并观察角膜水肿及手术并发症的发生情况.结果 线性爆破超声能量模式组较其他3组的实际超声时间明显缩短,累计超声能量明显减少,术后第1天视力提高明显,角膜内皮细胞密度损失少,角膜水肿发生率低;其差异均有统计学意义.结论 线性爆破模式是一种损伤轻效果好,一种新型的白内障超声乳化的手术方法.     

爆破式超声乳化在硬核白内障摘出术中的应用

目的 研究爆破式超声乳化术在硬核人障中的应用。方法 对７４例７４眼按硬度为Ⅳ～Ⅴ级的老年性成熟期或过熟期白内障施行爆破式超声乳化术,术中结合自制晶状体碎核钩进行手法劈核。结果 术后第１天、１ｗｋ及３ｍｏ裸眼视力达０．８及以上者分别为７５．６８７％、７９．７３％及８３．８７％,手术前后角散光改变无统计学意义（Ｐ〉０．０５）。角膜水肿５眼,晶状体后囊破裂５眼,少量晶状体物质沉入玻璃体内２眼。结论 该方法适合于硬核人障的超声乳化。     

Phacoemulsification parameters: series 20000 Legacy Versus Legacy with AdvanTec software and NeoSoniX handpiece

PURPOSE: To examine the differences in average phaco power and effective phaco time (EPT) and evaluate the clinical results with the standard Series 20000 Legacy system (Alcon) and the Legacy with AdvanTec software and the NeoSoniX handpiece (Alcon). SETTING: Department of Ophthalmology, University Hospital, Hradec Králové, Czech Republic. METHODS: The mean phaco power and EPT in 240 eyes of 240 consecutive patients having cataract surgery by a single surgeon using the standard Legacy 20000 system were retrospectively compared with results in 240 eyes of 240 consecutive patients operated on by the same surgeon using the Legacy with AdvanTec software and the NeoSoniX handpiece. Statistical analysis was performed using the Kruskal-Wallis 1-way analysis of variance. All chi-square (chi(2)) values are approximations. RESULTS: The EPT and mean phaco power were less in the AdvanTec-NeoSoniX group than in the standard Legacy 20000 group in all cases. The mean EPT was 56.9 seconds +/- 29.5 (SD) in the standard Legacy 20000 group and 4.2 +/- 3.8 seconds in the AdvanTec-NeoSoniX group. The mean phaco power was 19.2% +/- 6.2% and 5.1% +/- 2.5%, respectively. The difference between groups was statistically significant in EPT (age > or =90 years, chi(2) = 4.5, P =.034; age <90 years, chi(2)>57, P<.00005) and in mean phaco power (chi(2) = 4.58 and P =.032 and chi(2)>44 and P<.00005, respectively). No trace of corneal striae or edema was observed in 92% eyes on the first postoperative day. The best corrected visual acuity was 20/25 or better in 60% of cases. CONCLUSIONS: The Legacy system with AdvanTec software and the NeoSoniX handpiece significantly reduced the mean EPT and phaco power. This low-power technology minimizes intraoperative damage to ocular structures and maximizes the level and rapidity of visual rehabilitation.     

撕囊镊预劈核在白内障手术中的应用

目的:比较预劈核与非预劈核两种劈核方式,探讨撕囊镊预劈核的技术优点.方法:将年龄相关性白内障患者149例149眼随机分为预劈核组(A组)77眼和非预劈核组(B组)72眼.分别使用撕囊镊预劈核和非预劈核技术进行白内障超声乳化术,记录术中超声能量、平均超声乳化时间、术中并发症、术后1d,1wk裸眼视力和术后1、3d,1wk角膜水肿等情况并进行比较.结果:将两组中同级核硬度的亚组进行比较,A组的平均超声乳化时间低于B组,差异有统计学意义(P<0.05);且前者术后第1、3d角膜水肿轻于后者,差异有统计学意义(P<0.05),术后1d裸眼视力A组优于B组,差异有统计学意义(P<0.05),术后1wk两组裸眼视力无统计学差异(P>0.05).术中出现晶状体后囊膜破裂A组2眼(2.6%),B组有3眼(4.2%),两组比较,差异无统计学意义(χ2=0.28,P>0.05).结论:与非预劈核相比,撕囊镊预劈核操作更简便,术中超声时间更短,角膜水肿程度更轻,术后早期裸眼视力更好.     

摆动模式超声乳化白内障吸除术临床应用观察

目的 观察摆动模式超声乳化白内障吸除术的临床效果.方法 前瞻性随机对照研究.选择年龄相关性白内障患者659例(659只眼),随机(随机数字表法)分为摆动模式组(317只眼)与对照组(342只眼).两组患者均行超声乳化白内障吸除术.记录术前最佳矫正视力(BCVA)、白内障核硬度分级(Emery分级)、术中有效超声时间(EPT)、实际超声能量(AP).术后第1天和第7天检查角膜水肿程度和BCVA.两组AP和EPT数据比较采用t检验,术后第1天和第7天的角膜水肿程度采用非参数列联表分析.结果 摆动模式组和对照组晶状体核硬度为I～Ⅲ级的患者,术中AP分别为3.53%±1.76%和3.84%±1.93%,EPT分别为(0.23± 0.15)和(0.25 ±0.19)min,差异无统计学意义(t=1.19,0.83;P>0.05).术后第1天和第7天的角膜水肿程度和BCVA差异亦无统计学意义(x2=0.02,0.01;P>0.05).晶状体核硬度Ⅳ或V级的患者术中AP分别为6.31%±2.78%和9.45%±4.17%,EPT分别为(0.55±0.28)和(0.83±0.44)min,差异均有统计学意义(t=6.27,5.37;P<0.05).术后第1天两组角膜水肿程度和BCVA差异均有统计学意义(x2=11.77,P<0.05),但术后第7天角膜水肿程度和BCVA两组差异均无统计学意义(X2=0.45,P>0.05).结论 超声乳化白内障吸除术中,摆动模式对于硬度为Ⅳ或V级的晶状体核可降低超声能量、缩短超声乳化时间,提高超声乳化效率,减少组织损伤,有助于患者迅速恢复视力.     

1262例透明角膜缘切口行白内障超声乳化手术的临床观察

目的：探讨我院透明角膜缘切口行白内障超声乳化术的安全性和有效性。方法回顾性分析我院2011年1月至2013年8月行白内障超声乳化吸除联合折叠人工晶状体植入1262例（1739只眼）术后视力、人工晶状体植入率及并发症处理等情况。结果术中植入人工晶状体1731只眼（99．5％）,8只眼因后囊膜破裂未植入人工晶状体;术后1周矫正视力≥0．5者1268只眼,0．1～0．4者332只眼,＜0．1者139只眼。13只眼术后出现一过性高眼压,后囊破裂35只眼,角膜水肿中度357只眼,重度59只眼,角膜内皮失代偿1只眼,术后眼内炎3只眼。结论透明角膜缘切口行白内障超声乳化术具有麻醉简单、术后反应轻、视力恢复快的优点,只要规范操作,正确处理术后并发症,手术效果满意,是一种比较理想的手术方式。     

1.8mm同轴微切口白内障超声乳化术对角膜内皮及视力的影响

目的:探讨1.8mm同轴微切口白内障超声乳化术对角膜内皮损伤及术后视力恢复的影响.方法:选择2013-07/2015-07行白内障超声乳化吸除术患者120例145眼为研究对象,采用随机数字表法分为观察组60例73眼和对照组60例72眼,观察组采用1.8mm同轴微切口白内障超声乳化术,对照组采用传统3.2mm同轴切口白内障超声乳化术,比较两组患者术后裸眼视力(UCVA)、最佳矫正视力(BCVA)、切口部位角膜厚度、切口宽度、切口长度、黄斑中心凹视网膜厚度、手术源性散光、角膜内皮细胞计数、手术并发症等指标.结果:术后1wk,观察组UCVA、BCVA好于对照组,差异有统计学意义(t=3.604、7.109,P<0.05);术后1wk、1mo时,观察组切口宽度小于对照组,差异有统计学意义(t=205.3、225.2,P<0.05),切口长度大于对照组,差异有统计学意义(t=3.926、5.009,P<0.05);术后1wk,观察组黄斑中心凹视网膜厚度小于对照组,差异有统计学意义(t=2.817,P<0.05);观察组手术源性散光度小于对照组,差异有统计学意义(t=19.43、22.16,P<0.01);两组患者并发症(8.22% vs 11.11%)比较无统计学意义(x2=0.348,P>0.05).结论:1.8mm 微切口超声乳化技术有助于促进白内障患者视力恢复,可能与减轻角膜损伤、增强角膜闭合状态及降低术后术源性散光有关.     

Cataract phacoemulsification techniques: "divide and conquer" versus "stop and chop"--comparative evaluation of operation course and early results

PURPOSE: To compare ultrasound time, quality and quantity of intraoperative complications together with the eye condition in early postoperative period in patients who underwent "divide and conquer" and "stop and chop" cataract phacoemulsification. MATERIAL AND METHODS: "Divide and conquer" phacoemulsification was performed in 49 eyes, whereas "stop and chop" technique in 67 eyes. Before surgery axial lengths of the eye, anterior chamber depth and pupillary reflex were measured. During the surgery effective phaco time, nucleus hardness and all the complications were recorded, whereas in the first day post operation visual acuity and amount of corneal edema were examined. RESULTS: The ultrasound time was significantly shorter in patients operated with "stop and chop" technique. In the first postoperative day better visual acuity and smaller amount of corneal edema were observed in this group. CONCLUSIONS: "Stop and chop" technique gives better early postoperative results in comparison to "divide and conquer" technique. The number of intraoperative complications in both group is low.     

劈核技术在白内障超声乳化手术中的应用

目的 探讨劈核技术在白内障超声乳化手术中的应用。方法 用改良的劈裂乳化技术,施行２０６例白内障超声乳化摘。结果 术后３月矫正视力〉０．５者占９６．６％,角膜中度水肿５例,轻度水肿１５例,后囊破裂２例。结论 采用改良的劈裂乳化技术,使分割紧韧的晶状体核变得容易,减少了能量的应用,缩短了超声时间,提高了超声乳化摘出术的成功率。     

同轴2.2mm与2.8mm切口白内障超声乳化手术疗效评价

目的：：比较同轴微切口2.2mm与2.8mm切口白内障超声乳化手术疗效。方法：选择2014-07/2015-03我院年龄相关性白内障患者362例362眼,随机分成2.2 mm组(211例211眼)和2.8mm组(151例151眼)。术前记录裸眼视力、最佳矫正视力、屈光状态和角膜内皮计数结果。术中记录超声能量、超声乳化时间。术后记录裸眼视力、最佳矫正视力、屈光状态、角膜内皮计数。结果：两组患者术后裸眼及最佳矫正视力与术前相比均有明显提高,术后1wk时2.2mm组裸眼视力较2.8mm组提高明显,具有统计学意义(P<0.05)。2.2mm组患者在术后1wk角膜散光小于2.8mm组,两组比较有统计学差异(P<0.05)。两组患者术后角膜内皮计数都有不同程度的下降,但两组间没有统计学差异(P>0.05)。两组患者术中使用的超声能量及超声乳化时间没有统计学差异(P>0.05)。结论：2.2mm同轴微切口白内障超声乳化手术具有创伤小、恢复快、术后裸眼视力好、SIA小等优点,是一种值得推广的手术方式。     

老年性白内障晶状体核分级的CT与临床相关研究

目的:对比分析CT和临床Emery方法对老年性白内障晶状体核分级.方法:对111例132眼老年性白内障晶状体应用CT测定晶状体核CT值和Emery方法进行分级,分为CT组和Emery组,对比两组对应晶状体核分级的术后1d裸眼视力、1wk矫正视力,1d角膜水肿情况、实际超声能量(AP)、有效超声时间(EPT).结果:术后1d视力,Emery Ⅲ,Ⅳ组与CT Ⅲ,Ⅳ组比较,差异有统计学意义;Emery Ⅲ级核术中AP和EPT高于CT Ⅲ级核,Emery Ⅳ级核,AP,EPT均低于CT Ⅳ级核,差异有统计学意义;CT Ⅲ,Ⅳ级核较Emery Ⅲ,Ⅳ核术后1d角膜水肿程度有统计学差异.结论:对于Ⅲ,Ⅳ级核CT核分级方法可以作为Emery核分级方法的有效量化指标而对核硬度进行分级.     

Phaco-chop versus stop-and-chop nucleotomy for phacoemulsification

PURPOSE: To perform a comparative evaluation of phaco-chop versus stop-and-chop nucleotomy techniques of phacoemulsification. SETTING: Dr. Rajendra Prasad Center for Ophthalmic Sciences, New Delhi, India. METHODS: Forty eyes of 40 patients with immature senile cataract were included in the study. Twenty eyes each were randomly assigned to have phaco-chop (Group 1) or stop-and-chop (Group 2) nucleotomy during phacoemulsification. The main parameters were corneal endothelial count, effective phaco time, volume of infusion fluid used, central corneal pachymetry, best corrected visual acuity (BCVA), and intraoperative complications during nucleotomy. Follow-up visits were scheduled at 1, 4, and 12 weeks. RESULTS: The mean effective phaco time was 27 seconds +/- 18 (SD) in Group 1 and 28 +/- 16 seconds in Group 2. The mean corneal endothelial cell loss was 6.89% and 7.17%, respectively, at the end of 12 weeks. The difference between groups was not significant. An anterior capsule tear occurred in 3 eyes in Group 1 and 1 eye in Group 2. All eyes achieved a BCVA of 20/20 at the end of 4 weeks. There were no significant between-group differences in any intraoperative or postoperative parameter. CONCLUSIONS: The phaco-chop and the stop-and-chop nucleotomy techniques were equally efficacious for nuclear management during phacoemulsification.