Surgical approaches to correct corneal astigmatism at time of cataract surgery: a mini-review

Among refractive errors,astigmatism is the most common optical aberration,where refraction changes in different meridians of the eye.It causes blurred vision at any distance and includes corneal,lenticular,and retinal astigmatism.Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism,for example,a large size surgery incision.The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery.Nowadays,three surgical approaches can be used.By placing a sutureless clear corneal incision on the steep meridian of the cornea,a preoperative corneal astigmatism less than 1.0 D can be corrected.Single or paired peripheral corneal relaxing incisions(PCRIs)provide 1.0-3.0 D corneal astigmatism correction.PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism,if more than 2.0 D,the risk of overcorrection and irregular astigmatism is increased.When toric intraocular lenses(IOLs)are unavailable in markets,PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism.Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism.Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D.These approaches can be used alone or in combination.

Toric Intraocular Lens vs. Peripheral Corneal Relaxing Incisions to Correct Astigmatism in Eyes Undergoing Cataract Surgery

Purpose:.To compare toric intraocular lens implantation(ToricIOL).with peripheral corneal relaxing incisions(PCRIs) for astigmatism correction in patients undergoing cataract surgery.Methods: 54 patients(54 eyes) with more than 0.75 diopter(D).of preexisting corneal astigmatism were classified as group A(0.75-1.50D) or group B(1.75-2.50D). The patients were randomized to undergo Toric-IOL or PCRIs in the steep axis with spherical IOL implantation..Log MAR uncorrected visual acuity(Log MAR UCVA), Log MAR best corrected vi sual acuity.(Log MAR BCVA),.error of vector(|EV|), surgery induced refraction correction.(|SIRC |),.and correction rates(CR) were measured 1 month and 6 months postoperatively.Results: At 6 months postoperatively, all 54 eyes had LogMAR BCVA≤0.2. Patients who underwent PCRIs and ToricIOL with Log MAR BCVA≤0.1 showed no significant differences in group A(P=1.00) or in group B(P=0.59). Group A showed no significant differences in Log MAR UCVA(P =0.70), |EV|(P=0.13), |SIRC|(P=0.71), and CR(P=0.56)in patients underwent PCRIs and Toric-IOL. However, group B showed significant differences in Log MAR UCVA(P <0.01), |EV|(P<0.01)), |SIRC|(P<0.01), and CR(P<0.01).The Log MAR UCVA and |EV | between 1 and 6 months showed no significant differences in patients in group A. However, in group B, they are significant differences.Conclusion:.The efficacy and stability of Toric-IOL and PCRIs were equal in low astigmatic patients..Toric-IOL achieved an enhanced effect over PCRIs in higher astigmatic patients.PCRIs had the more refractive regression than Toric-IOL in 6months.

Influence of preoperative astigmatism on corneal biomechanics and accurate intraocular pressure measurement after micro-incision phacoemulsification

AIM: To define the corneal hysteresis(CH), corneal resistance factor(CRF), Goldmann-correlated intraocular pressure(IOPg) and corneal compensated intraocular pressure(IOPcc) prior to and following coaxial micro-incision phacoemulsification in patients with corneal astigmatism. METHODS: Of 97 patients with cataracts were enrolled in the study. Group 1 included patients with corneal astigmatism(K1-K2) values of K1-K2<+1.0 D, and group 2 with values of K1-K2 ≥+1.0 D and ≤+2.25 D. Coaxial micro-incision phacoemulsification of a corneal incision of 2.0 mm with intraocular lens(IOL) implantation was performed. CH, CRF, IOPg, IOPcc, waveform score(WS) were measured preoperatively and one week, one month postoperatively using an Ocular Response Analyzer. Axial length(AXL) was calculated by Tomey Optical Biometer OA 2000.RESULTS: Group 1 consisted of 51 patients with mean corneal astigmatism value of +0.49±0.25 D. Group 2 included 46 patients with astigmatism of +1.43±0.43 D. In group 1, CRF(t=2.68, P<0.05), CH(t=2.64, P<0.05) and WS(t=3.51, P<0.05) were significantly lower one week postoperatively, when compared to the preoperative values. CRF significantly decreased(t=3.61, P<0.05) when measured one month following the surgery. In group 2 CH(t=5.92, P<0.05), and WS(t=3.96, P<0.05) were significantly lowered one week after cataract surgery. Moreover, we observed a significant decrease in IOPg(t=2.24, P<0.05), CRF(t=5.05, P<0.05) and CH(t=2.31, P<0.05) one month after phacoemulsification. There was no statistically significant(t=-0.83, P=0.41) difference in AXL between study groups.CONCLUSION: CRF, CH and IOPg are reduced in patients with preoperative corneal astigmatism equal or higher than +1.0 D and lower than +2.25 D. Hence, bias of IOPg measurement in these patients may cause underestimation of the real IOP both before and after cataract surgery. The measurement of IOPcc allows the precise assessment of IOP pre-and postoperatively, independently on corneal astigmatism, CH and CRF values.

Case report:simultaneous femtosecond laser astigmatic keratotomy and toric intraocular lens implantation in femtosecond laser-assisted cataract surgery in a patient with surgically induced high corneal astigmatism

Background:Femtosecond laser astigmatic keratotomy(FSAK)and toric intraocular lens(IOL)implantation have been studied individually for comparison to treat astigmatism at cataract surgery.We report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty(LTK)in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery(FLACS).This is the first report of both procedures combined simultaneously,with or without history of LTK.Case Description:A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004,with subsequent surgically induced high corneal astigmatism,and with age-related nuclear cataract of both eyes.IOL master demonstrated+7.71 diopters of astigmatism at 163 degree right eye and+3.29 diopters of astigmatism at 4 degree left eye.After extensive discussion of the risks and benefits,the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions(RIs)and toric IOL(Alcon SN6AT9)right eye;FLACS with toric IOL(Alcon SN6AT7)alone left eye.At 2-year follow-up,uncorrected visual acuity was 20/30 right eye,20/25 left eye.His best corrected visual acuity was 20/25(+0.25+1.00 axis 21)right eye and 20/20(plano+0.25 axis 90)left eye;his best corrected near visual acuity was J1+with add+2.50 diopters right eye and left eye.Conclusions:Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract surgery.An effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9,in our case,simultaneously,which can achieve an excellent long term visual outcome.

Effect of phacoemulsification on vision and intraocular pressure and corneal astigmatism

Objective:To explore the effect of phacoemulsification in combined with intraocular lens implantation incision site selection on the visual function, intraocular pressure, and corneal astigmatism in patients with cataract.Methods:A total of 72 patients (85 eyes) with cataract who were admitted in our hospital from April, 2015 to October, 2016 were included in the study. All the patients were performed with phacoemulsification in combined with intraocular lens implantation. The patients were divided into the observation group (n=36, 43 eyes) and the control group (n=36, 42 eyes) according to different surgical incision sites. A transparent corneal incision with a length of 3.0 mm was made along the meridian axial position with the maximum corneal refractive power in the observation, while a transparent corneal incision with a length of 3.0 mm was made above the temple or nose in the control group. Routine disposition and follow-up visit were given for the patients in the two groups after operation. BCVA, intraocular pressure, corneal astigmatism, and corneal endothelial cell count in the two groups before and after operation were compared.Results:BCVA after operation in the two groups was significantly elevated, while the corneal endothelial cell count was significantly reduced, but the comparison of BCVA and corneal endothelial cell count between the two groups was not statistically significant. The intraocular pressure after operation in the two groups was elevated first and reduced later. The intraocular pressure 2 h and 1 d after operation was significantly elevated when compared with before operation. The intraocular pressure 2 d after operation was not significantly different from that before operation. The comparison of intraocular pressure at each timing point after operation between the two groups was not statistically significant. The corneal astigmatism after operation in the two groups was elevated first and reduced later. The surgically induced astigmatism 7 d-6 months after operation was significantly reduced, and the average corneal astigmatism 7 d-6 months after operation in the observation group was significantly lower than that in the control group. The surgically induced astigmatism 1-6 months after operation in the observation group was significantly lower than that in the control group.Conclusions: Phacoemulsification in combined with intraocular lens implantation incision site selection including maximum corneal refractive power site and routine surgical incision can improve the patients' vision, but the maximum corneal refractive power site surgical incision can reduce the postoperative corneal astigmatism, and has a certain advantage.

Correction of low corneal astigmatism in cataract surgery

· AIM: To evaluate and compare aspheric toric intraocular lens(IOL) implantation and aspheric monofocal IOL implantation with limbal relaxing incisions(LRI) to manage low corneal astigmatism(1.0-2.0 D) in cataract surgery.· METHODS: A prospective randomized comparative clinical study was performed. There were randomly recruited 102 eyes(102 patients) with cataracts associated with corneal astigmatism and divided into two groups. The first group received toric IOL implantation and the second one monofocal IOL implantation with peripheral corneal relaxing incisions. Outcomes considered were: visual acuity, postoperative residual astigmatism, endothelial cell count, the need for spectacles, and patient satisfaction. To determine the postoperative toric axis, all patients who underwent the toric IOL implantation were further evaluated using an OPD Scan III(Nidek Co, Japan). Follow-up lasted 6mo.· RESULTS: The mean uncorrected distance visual acuity(UCVA) and the best corrected visual acuity(BCVA) demonstrated statistically significant improvement after surgery in both groups. At the end of the follow-up the UCVA was statistically better in the patients with toric IOL implants compared to those patients who underwent implantation of monofocal IOL plus LRI. The mean residual refractive astigmatism was of 0.4 D for the toric IOL group and 1.1 D for the LRI group(P 【0.01). No difference was observed in the postoperative endothelial cell count between the two groups.· CONCLUSION: The two surgical procedures demonstrated a significant decrease in refractive astigmatism. Toric IOL implantation was more effective and predictable compared to the limbal relaxing incision.

Posterior corneal astigmatism modifications after cataract surgery and its role on total corneal astigmatism

Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total astigmatism.This study aims to ascertain if there is significant change in the posterior corneal astigmatism after cataract surgery and its impact on the total astigmatism.Methods:Analysis of 76 eyes that underwent cataract surgery with monofocal intraocular lens implantation.Corneal topography was performed with Pentacam(OCULUS®)pre-and post-operatively.Total corneal astigmatism was calculated with the algorithm of vergence tracing.We compared preoperative and postoperative changes in the magnitude and axis differences of anterior corneal curvature astigmatism,posterior corneal curvature astigmatism and the calculated total corneal astigmatism.We calculated the correlation between the total preoperative astigmatism and the difference between total corneal astigmatism and anterior corneal astigmatism.Results:The mean preoperative and postoperative posterior astigmatism was 0.31±0.02 D,showing no significant differences before and after surgery(P=0.989).Statistically significant differences between the calculated total corneal astigmatism and anterior corneal astigmatism were registered preoperatively and postoperatively in the with-the-rule anterior(WTR)corneal astigmatism(P=0.004,P<0.0001);against-the-rule(ATR)anterior corneal astigmatism(P<0.0001,P<0.0001)and in the oblique(P=0.026,P=0.019)subgroups.The posterior corneal astigmatism and the total corneal astigmatism correlated positively with the differences between the total corneal and anterior corneal astigmatism(R=0.378,P=0.001).Conclusions:There were statistically significant differences between the magnitude of the total astigmatism and anterior corneal astigmatism,underlining the impact of posterior corneal astigmatism.A positive correlation between the preoperative posterior astigmatism and the difference between the total corneal and the anterior corneal astigmatism suggests a specially relevant role of posterior corneal astigmatism when evaluating patients with higher degrees of astigmatism.

Rotational stability of plate haptic toric intraocular lenses after combined 25-gauge vitrectomy and cataract surgery

AIM:To evaluate the postoperative intraocular lens(IOL)rotational stability and residual refractive astigmatism following combined 25-gauge vitrectomy and cataract surgery with implantation of a plate haptic toric IOL.METHODS:In this retrospective case series,32 eyes of 32 patients underwent a combined 25-gauge vitrectomy and phacoemulsification for vitreoretinal diseases and cataract with regular corneal astigmatism of at least 1 diopter(D).A plate haptic toric IOL(AT Torbi 709M,Carl Zeiss Meditec AG)was implanted in all eyes.The outcome measures were rotational stability and refractive astigmatism up to 6mo postoperatively as well as the best corrected visual acuity(BCVA).RESULTS:Preoperative refractive astigmatism was 2.14±1.17 D,which was significantly reduced to 0.77±0.37 D six to eight weeks postoperatively and remained stable throughout the observation period(0.67±0.44 D at three months and 0.75±0.25 D at six months;for all groups:P<0.0001 compared to baseline).BCVA improved significantly from 0.36±0.33 logMAR preoperatively to 0.10±0.15 logMAR following surgery(P=0.02).Mean IOL axis deviation from the target axis was 3.4°±2.9°after six to eight weeks and significantly decreased over time(2.4°±2.6°six months after surgery;P=0.04).In one patient IOL,re-alignment was performed.CONCLUSION:Corneal astigmatism is significantly reduced following combined 25-gauge vitrectomy and cataract surgery.The plate haptic toric IOL position and axis remain stable during the observation period of six months.

The impact of posterior corneal astigmatism on the surgical planning of toric multifocal intraocular lens implantation

Purpose:To investigate the influence of posterior corneal astigmatism on the prediction accuracy of toric multi­focal intraocular lens(IOL)calculation.Methods:The keratometric astigmatism measured by Lenstar LS 900(KCA_(L)),keratometric astigmatism(KCAp)and total corneal astigmatism(TCA)measured by Scheimpflug camera(Pentacam HR)were documented and analyzed accordingly.Three deduction models using different parameters were compared.Model 1:KCA_(L)+keratometric comeal surgically induced astigmatism(KCSIA,0.30 D@50°);Model 2:KCA_(P)+KCSIA);Model 3:TCA 4-total CSIA(TCSIA,0.23 D@50°).The prediction errors of each model as the difference vector between the actual and the intended residual astigmatism were compared.Results:Seventy-six eyes implanted with toric multifocal IOLs were included in this study.The vector differences of the actual KCSIA and TCSIA were statistically significant in the total sample and against-the-rule(ATR)sub­group(both P<0.05).Model 1 deduced the smallest mean values of prediction error,while that of Model 3 were smaller than that of Model 2,both in the total sample and the ATR subgroups(all P<0.05).Meanwhile,in the total sample and ATR subgroups,the centroid vector magnitudes of Model 3 were smaller than that of Model 1(0.31±0.76 D and 0.39±0.76 D).Conclusions:The calculation of toric multifocal IOL should be individualized especially in the ATR eyes for the impact of PCA on the estimation of the preoperative comeal astigmatism and the CSIA.

人工晶状体保护下超声乳化白内障吸除术疗效及安全性评价:一项随机对照临床研究

目的观察人工晶状体(IOL)保护下超声乳化手术(PHACO)对硬核白内障患者的治疗效果。方法采用随机对照临床研究方法,连续纳入2019年1月至2022年5月于延边大学附属医院收治的Emery分级Ⅳ~Ⅴ级的硬核白内障患者120例120眼,按照随机数字表法分为PHACO组、IOL保护PHACO组和囊外白内障摘除术(ECCE)组,分别行常规PHACO、IOL保护下的PHACO和ECCE,每组40例40眼。最终99例受试者完成随访,其中PHACO组30例30眼,IOL保护PHACO组35例35眼,ECCE组34例34眼。记录各组总手术时间、术中超声乳化时间、累计释放能量。术后随访3个月,检测并比较3个组患眼角膜内皮细胞密度(ECD)、角膜内皮细胞面积变异系数(CV)、角膜六角形内皮细胞比率(6A)、角膜散光值,不同等级裸眼远视力的眼数分布;记录术中和术后并发症发生情况。结果IOL保护PHACO组与PHACO组超声能量及超声时间比较差异均无统计学意义(P=0.691、0.982)。IOL保护PHACO组和PHACO组总手术时间分别为(38.81±2.73)和(36.45±3.45)min,明显短于ECCE组的(69.60±4.35)min,差异均有统计学意义(均P<0.001)。术前3个组患者年龄、性别、晶状体核硬度等基本资料比较,差异均无统计学意义(均P>0.05)。术后3个月,PHACO组和IOL保护PHACO组裸眼视力较高的人数较ECCE组高(P=0.006、0.007);IOL保护PHACO组的ECD和6A分别为(2155.57±177.88)/mm^(2)和(41.31±5.18)%,均显著高于PHACO组的(1912.64±224.11)/mm^(2)和(36.18±3.27)%,IOL保护PHACO组的CV为(50.34±5.90)%,低于PHACO组的(55.67±3.30)%,差异均有统计学意义(P=0.007、0.003、0.005)。术后1周和3个月,IOL保护PHACO组的角膜散光度数均显著低于ECCE组,且高于PHACO组,差异均有统计学意义(均P<0.05)。结论IOL保护下的PHACO相对常规PHACO可有效减少超声能量对角膜内皮的损伤,相对ECCE能明显缩短手术时间,减轻术后炎症反应,且并未明显增加术后角膜散光。IOL保护下的PHACO是硬核白内障患者一种有效的改良手术方式。

藏族年龄相关性白内障患者眼球生物学参数特征分析

目的:比较藏族与汉族年龄相关性白内障患者眼球生物学参数的差异,分析藏族患者眼球生物学参数的分布特征。方法:回顾性队列研究。收集2019-01/2020-12就诊于我院的年龄相关性白内障患者661例1 030眼,其中藏族患者483例739眼,汉族患者178例291眼。术前所有患者均采用IOL Master 500测量眼轴长度、前房深度、角膜曲率、散光及散光轴向。结果:藏族年龄相关性白内障患者眼轴长度为23.33(22.81,23.86)mm,前房深度为3.04(2.79,3.30)mm,散光度为0.73(0.47,1.07)D,平均角膜曲率为43.89±1.35 D,较汉族患者眼轴短,角膜曲率小(均P<0.05)。藏族患者的年龄与眼轴长度和前房深度均呈负相关,而与平均角膜曲率呈正相关(均P<0.05)。藏族患者中男性患者较女性患者眼轴更长、前房更深、角膜更平坦(均P<0.05)。结论:藏族与汉族年龄相关性白内障患者的眼球生物学参数存在差异,不同年龄和性别藏族患者眼球生物学参数的分布有所变化。

智能手机辅助新型标记法在白内障术中标记目标轴位的准确性

目的:评估一种智能手机辅助的新型“任意点两步法”在白内障超声乳化吸出联合人工晶状体植入术中寻找目标轴位的便利性和准确性。方法:前瞻性观察性研究。选取2021-10/2022-04于我院拟行白内障超声乳化吸出联合人工晶状体植入术的年龄相关性白内障患者62例62眼。随机分为两组,对照组31例31眼采用裂隙灯下标记的“传统两步法”标记人工晶状体的目标轴位,试验组31例31眼采用智能手机辅助的“任意点两步法”标记人工晶状体的目标轴位。术中均采用Callisto eye导航系统作为标准参照,计算参照标记点的偏差值(偏差-1)、目标轴位标记点的偏差值(偏差-总)和参照标记点到目标轴位标记点夹角的偏差值(偏差-2),并记录术前轴位标记用时。结果:试验组偏差-1值和偏差-总值均低于对照组(1.06°±1.39°vs 2.48°±2.23°,1.77°±1.54°vs 2.81°±1.58°,均P<0.01),但两组偏差-2值无明显差异(1.35°±1.40°vs 1.48°±1.79°,P>0.05)。试验组术前轴位标记用时短于对照组(1.77±1.70 min vs 2.88±3.20 min,P<0.01)。结论:与“传统两步法”相比,智能手机辅助的“任意点两步法”在白内障超声乳化吸出联合人工晶状体植入术中寻找目标轴位的过程操作简便省时、准确性高。

超声乳化中强轴角膜切口在白内障患者中的应用分析

目的:探讨超声乳化中强轴角膜切口在白内障患者中的应用效果。方法:选取2021年10月—2022年10月样本医院收治的260例白内障患者作为研究对象,所有患者均接受白内障超声乳化手术治疗,根据不同手术切口将其分为观察组(n=146,强轴角膜切口)和对照组(n=114,右上方或颞侧透明角膜切口),手术切口均为3 mm;对比两组患者术前、术后1个月、术后3个月视力恢复情况[最佳矫正视力(BCVA)]和角膜散光度情况。结果:术后1个月、术后3个月,观察组与对照组相比,BCVA较高、角膜散光度较低,差异有统计学意义(t=2.975、2.055;t=7.019、9.427;P<0.05);观察组与对照组相比,前房出血、角膜切口灼伤、后囊膜破裂、后角膜水肿并发症总发生率观察组低于对照组,差异有统计学意义(χ^(2)=4.572,P<0.05)。结论:选用强轴角膜切口作为白内障超声乳化手术的切口效果较好,有助于患者视力恢复,近期对角膜散光度的影响较小,还可降低术后并发症发生率。

飞秒激光松解角膜散光联合三焦点人工晶状体植入术后的疗效观察

目的探讨飞秒激光松解角膜散光联合三焦点人工晶状体植入术后的短期临床效果。方法收集2019年9月—2021年3月在本院接受飞秒激光辅助超声乳化白内障摘除术的白内障患者29例35眼,所有患者术中均行飞秒激光角膜缘松解切口及蔡司三焦点人工晶状体植入,观察患者术后3个月裸眼及最佳矫正远、中、近视力及散光变化,记录手术并发症发生情况、术后脱镜率及满意度。结果术后3个月裸眼及最佳矫正远视力均较术前明显提高,差异均具有统计学意义(P=0.000)。所有患者术后3个月均获得良好的裸眼及最佳矫正中程视力和近视力。术后3个月散光较术前明显降低,差异有统计学意义(P=0.000)。散光矫正指数<1,存在欠矫现象。术后3个月平均残余散光(0.54±0.24)D,<0.75D,患者术后3个月获得较高的视觉质量。所有患者手术过程顺利,术中及术后随访过程中未发现手术并发症。术后3个月,患者脱镜率为94.3%,满意度为94.3%,获得较高的脱镜率和满意度。结论飞秒激光松解角膜散光不仅有效,还拓宽了三焦点人工晶状体的适应范围,极大地提高了白内障患者术后视觉质量。

预装式疏水性丙烯酸酯类人工晶体和同轴微切口对年龄相关性白内障疗效分析

目的探讨与分析预装式疏水性丙烯酸酯类人工晶体和同轴微切口对年龄相关性白内障的疗效影响。方法选择2020年8月—2023年5月在蓝田华阳眼科医院诊治的80例年龄相关性白内障患者作为研究对象,根据随机数表法将其分为对照组和研究组,每组40例。所有手术均由同一位医师完成,都采用预装式疏水性丙烯酸酯类人工晶体植入,研究组行2.2 mm同轴透明角膜隧道微切口,对照组行3.0 mm透明角膜隧道切口,比较两组的最佳矫正、并发症发生情况、角膜散光度与前房深度变化情况。结果研究组术后1周与术后1个月的最佳矫正视力都高于对照组,差异有统计学意义(P<0.05);两组术后1个月的最高矫正视力与术后1周相比都升高,差异有统计学意义(P<0.05)。研究组术后1个月的角膜水肿、眼内炎、晶体混浊、囊膜破损等并发症发生率显著低于对照组,差异有统计学意义(P<0.05)。研究组术后1周与术后1个月的角膜散光度都低于对照组,差异有统计学意义(P<0.05);两组术后1个月的角膜散光度与术后1周相比都降低,差异有统计学意义(P<0.05)。研究组术后1周与术后1个月的前房深度都高于对照组,差异有统计学意义(P<0.05);研究组与对照组术后1个月与术后1周的前房深度比较,差异无统计学意义(P>0.05)。结论预装式疏水性丙烯酸酯类人工晶体联合同轴微切口在年龄相关性白内障患者的应用并不会影响患者的前房深度,能减少角膜散光度,提高患者的术后视力,减少并发症的发生。

陡峭轴切口联合对侧角膜缘松解术矫正白内障合并角膜散光患者的疗效

目的观察白内障患者行陡峭轴切口联合对侧角膜缘松解术后角膜散光和视力的变化。方法选取2020年1月至12月在蚌埠医学院第一附属医院眼科就诊的年龄相关性白内障合并角膜散光(>1.50 D)患者29例(30眼)为研究对象,所有患者均行陡峭轴切口联合对侧角膜缘松解术,观察术前及术后1周、1个月、3个月患者的裸眼视力(UCVA)、最佳矫正视力(BCVA)及角膜散光情况,并进行统计学分析。结果患眼术前角膜散光为(2.16±0.65)D,术后1周、1个月、3个月角膜散光分别为(0.97±0.46)D、(0.84±0.49)D、(0.87±0.47)D;术后各时间点患眼角膜散光均较术前明显降低(均为P<0.05);术后各时间点间两两相比,患眼角膜散光差异均无统计学意义(均为P>0.05)。术前UCVA为0.11±0.08,术后1周、1个月、3个月分别为0.56±0.18、0.71±0.16、0.73±0.16。术前BCVA为0.18±0.11,术后1周、1个月、3个月分别为0.67±0.15、0.82±0.11、0.83±0.09。术后各时间点患眼UCVA及BCVA均较术前明显提高(均为P<0.05);术后1周与术后1个月、3个月患眼UCVA及BCVA相比,差异均有统计学意义(均为P<0.05);术后1个月与术后3个月的UCVA及BCVA相比差异无统计学意义(P>0.05)。术后1个月UCVA≥0.6的患眼占90.0%。结论陡峭轴切口联合对侧角膜缘松解术能够有效矫正白内障合并角膜散光,使患者获得更佳的术后视觉质量。

改良四点固定人工晶状体悬吊术后角膜曲率及散光的变化

目的比较改良四点固定与传统两点固定人工晶状体悬吊植入术后角膜曲率及散光的变化,以寻求提高人工晶状体悬吊术后视觉质量的更佳手术方式。方法回顾性病例研究。选取2020年7月至2021年10月于保定市第一中心医院眼二科行改良四点固定人工晶状体悬吊植入术患者28例(28只眼)为A组,行传统两点固定人工晶状体悬吊植入术患者29例(29只眼)为B组,两组患者术前术后应用Sirius角膜地形图仪测量角膜曲率K1、K2值及散光值,术后3个月随访,比较两种手术方式术后角膜曲率及散光的差异性。结果A组术前K1(43.57±0.63),术后3个月K1(43.58±0.70),与术前相比差异无统计学意义(t=-1.20,P>0.05);术前K2(44.19±0.68),术后3个月K2(44.46±0.63),与术前相比差异有统计学意义(t=-3.16,P<0.05);术前角膜散光(-0.81±0.30)D,术后3个月角膜散光(-1.10±0.32)D;与术前相比差异有统计学意义(t=5.26,P<0.05)。B组术前K1(43.50±1.04),术后3个月K1(42.98±1.24),与术前相比差异有统计学意义(t=4.95,P<0.05);术前K2(44.12±1.13),术后3个月K2(44.71±1.03),与术前相比差异有统计学意义(t=-6.12,P<0.05);术前角膜散光(-0.76±0.41)D,术后3个月角膜散光(-2.08±0.94)D;与术前相比差异有统计学意义(t=14.28,P<0.05)。A组术前术后角膜散光差值(-0.29±0.29)D,B组术前术后角膜散光差值(-1.31±0.50)D,两组相比差异有统计学意义(t=-9.46,P<0.05)。结论与传统两点固定法相比,改良四点固定人工晶状体悬吊植入术后角膜散光变化更小。

新型彩色LED角膜分析仪Cassini测量角膜曲率及计算人工晶状体度数的准确性

目的:评估新型角膜分析仪Cassini测量角膜曲率和角膜散光的重复性,及其与人工晶状体生物测量仪IOLMaster的一致性。进一步分析该设备在IOL度数计算上的精确性。方法:本研究共纳入了77例白内障患者的77眼。由一名操作者使用Cassini角膜分析仪和IOLMaster生物测量仪分别测量患者角膜曲率和角膜散光相关参数各3次,包括平坦角膜曲率(Kf)、陡峭角膜曲率(Ks)、角膜散光(Ast)、总角膜屈光力(TCP)和总角膜散光(TCA)。采用组内标准差(Sw)、重测度(TRT)和组内相关系数(ICC)评估数据的重复性。采用Bland-Altman图和95%一致性区间(LoA)评估一致性。通过比较术后3个月IOLMaster和Cassini使用4种不同IOL计算公式时的平均绝对预测误差(MAE)和术后误差分布范围进一步分析Cassini预测IOL度数的准确性。结果:Cassini测量Kf、Ks和TCP的TRT值均≤0.55 D,且ICC值均≥0.966。在散光相关参数方面,Ast的TRT值和ICC值分别为0.47 D和0.973,TCA的TRT值和ICC值分别为0.75 D和0.953,Ast的矢量分解J_0和J_(45)以及TCA的矢量分解J_0-TCA和J_(45)-TCA的TRT值均≤0.48 D,且ICC值均≥0.893。Bland-Altman图显示Cassini和IOLMaster测量Kf和Ks的95%LoA分别为0.73 D和0.63 D。IOLMaster和Cassini在各公式下的MAE均小于0.43 D。不同屈光度的分布情况也显示,两种设备使用不同公式计算的IOL度数术后屈光误差在±0.25 D、±0.50 D、±0.75 D和±1.00 D以内的患者分别超过了28%、62%、85%和94%。结论:除了TCA外,新型彩色LED角膜分析仪Cassini测量正常人角膜曲率和角膜散光的重复性良好,且与IOLMaster生物测量仪测量的Ks和Kf一致性好。在IOL度数预测误差上,Cassini和IOLMaster相似,能够保证其在临床应用的可行性。

学龄前散光儿童近视化进展及影响因素分析

目的 探讨学龄前散光儿童化近视化进展并分析等效球镜度(spherical equivalent,SE)和眼轴(axial length,AL)变化量的影响因素。方法 选取2021年1—9月北京市海淀区妇幼保健院眼科门诊就诊的学龄前散光儿童,1年后随访患儿SE和AL的变化量,采用多重线性回归分析SE和AL变化量的影响因素。结果 共纳入179例患儿,其中男89例,女90例,年龄3~<7岁,平均(4.3±0.9)岁。1年复查时散光儿童SE降低0.63(0.25,0.75)D,AL增加(0.25±0.11)mm,AL/角膜曲率半径(corneal radius,CR)增加0.03±0.02。多重线性回归结果显示,基线AL和戴镜矫正是SE变化量的影响因素(P <0.05),其中基线AL对SE变化量影响最大,其次是戴镜矫正,SE变化量随着基线AL增加,未戴镜矫正者增加;基线AL、父母近视、戴镜矫正和近距离用眼是AL变化量的影响因素(P <0.05),其中基线AL对AL变化量影响最大,其次是近距离用眼时间和戴镜矫正,父母近视影响最小,AL变化量随着基线AL增加、近距离用眼时间增加,未戴镜矫正者、父母近视者而增加。结论 学龄前散光儿童的屈光度向近视化方向发展。基线AL、近距离用眼、父母近视是散光儿童近视化进展的危险因素,戴镜矫正可延缓散光儿童近视化进展。

散光矫正型人工晶状体植入在白内障低角膜散光中的应用进展

在我国,白内障是一种十分常见的致盲眼病,其中约20%的患者术前有角膜散光。随着患者对术后视力要求的不断提高,白内障手术正逐步向屈光性方向发展,目的是提高术后视觉质量。散光矫正型人工晶状体(toric intraocular lens,Toric IOL)植入是当前最常见的矫正角膜散光的术式,对术前角膜散光进行矫正,并控制手术源性散光,从而降低术后角膜散光,对提高患者的术后视力有积极作用。基于此,本文将对Toric IOL在白内障低角膜散光中的应用作一简要综述。