Three-year results of small incision lenticule extraction and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis for correction of high myopia and myopic astigmatism

AIM： To compare and calculate the 3-year refractive results, higher-order aberrations （HOAs）, contrast sensitivity （CS） and dry eye parameters after small incision lenticule extraction （SMILE） and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis （FS-LASIK） for correction of high myopia and myopic astigmatism. METHODS： In this prospective, non-randomized comparative study, 78 eyes with spherical equivalent （SE） of -8.11±1.09 diopters （D） received a SMILE surgery, and 65 eyes with SE of -8.05±1.12 D received a wavefront-guided FS-LASIK surgery with the VisuMax femtosecond laser （Carl Zeiss Meditec, Jena, Germany） for flap cutting. Visual acuity, manifest refraction, CS, HOAs, ocular surface disease index （OSDI） and tear break-up time （TBUT） were evaluated during a 3-year follow-up. RESULTS： The difference of uncorrected distance visual acuity （UDVA） postoperatively was achieved at lmo and at 3mo, whereas the difference of the mean UDVA between two groups at 3y were not statistically significant （t=-1.59, P=-0.13）. The postoperative change of SE was 0.89 D in the FS-LASIK group （t=5.76, P=0.00）, and 0.14 D in the SMILE group （t=-0.54, P=0.59） from lmo to 3y after surgery. At 3-year postoperatively, both HOAs and spherical aberrations in the SMILE group were obviously less than those in the FS-LASIK group （P=0.00）, but the coma root mean square （RMS） was higher in the SMILE group （0.59±0.26） than in the FS-LASIK group （0.29±0.14, P=0.00）. The mesopic CS values between two groups were not statistically significant at 3y postoperatively. Compared with the FS-LASIK group, lower OSDI scores and longer TBUT values were found in the SMILE group at Imo and 3mo postoperatively. With regard to safety, no eye lost any line of CDVA in both groups at 3y after surgery. CONCLUSION： Both SMILE and wavefront-guided FS- LASIK procedures provide good visual outcomes. Both procedures are effective and safe, but SMILE surgery achieve more stable long-term refractive outcome and better control of early postoperative dry eye as compared to FS-LASIK.

Combined Carbon Dioxide Laser Lateral Canthotomy and Femtosecond Laser-Assisted Cataract Surgery

Purpose: The purpose of this study was to evaluate a new procedure aimed at lengthening the palpebral fissure to facilitate femtosecond laser-assisted cataract surgery in patients with small eyes. Method: A quick procedure using the CO2 laser was adapted for patients with small eyes undergoing laser-assisted cataract surgery using the Catalys system. The UniPulse CO2 laser (Nidek) was used for laser lateral canthotomy on patients with small palpebral fissures to allow fitting of the Liquid OpticTM Interface eyepiece. Results: Lateral canthotomies were performed on 19 women and 7 men (ages ranged from 45 to 93 years) with lower eyelid lengths equal to or shorter than 32 mm who then underwent femtosecond laser-assisted cataract surgery. A total of 33 eyelids received laser lateral canthotomy with the CO2 laser;only one eyelid had lateral canthotomy with cold-steel tenotomy scissors. Dockings were completed for all 34 eyes with eyelids receiving lateral canthotomies. The 33 eyes with eyelids that received laser canthotomy with the CO2 laser had successful femtosecond laser-assisted cataract surgery. The one eye with the eyelid that received cold-steel canthotomy could not have femtosecond laser-assisted cataract surgery despite successful docking because of pupillary constriction. The findings were statistically significant;Fisher Exact Test showed a p-value of 0.0294. Conclusion: Laser lateral canthotomy with CO2 laser is a safe and effective method to allow docking and completion of femtosecond laser-assisted cataract surgery.

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.

Comparison of early changes in ocular surface markers and tear inflammatory mediators after femtosecond lenticule extraction and FS-LASIK

AIM:To compare the short-term impacts of femtosecond lenticule extraction(FLEx)and femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK)on ocular surface measures and tear inflammatory mediators.METHODS:This prospective comparative nonrandomized clinical study comprised 75 eyes(75 patients).Totally 20 male and 15 female patients(age 21.62±3.25 y)with 35 eyes underwent FLEx,and 26 male and 14 female patients(age 20.18±3.59 y)with 40 eyes underwent FS-LASIK.Central corneal sensitivity,noninvasive tear breakup time,corneal fluorescein staining,Schirmer I test,tear meniscus height,and ocular surface disease index were evaluated in all patients.Tear concentrations of nerve growth factor(NGF),interleukin-1α(IL-1α),transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ),and matrix metalloproteinase-9(MMP-9)were assessed by multiplex antibody microarray.All measurements were performed preoperatively,and 1 d,1 wk,and 1 mo postoperatively.RESULTS:Patients who underwent FLEx exhibited a more moderate reduction in central corneal sensation and less corneal fluorescein staining than those in the FS-LASIK group 1 wk after the procedure(P<0.01).NGF was significantly higher 1 d and 1 wk after surgery in the FS-LASIK group than in the FLEx group(P<0.01).By contrast,compared to those in the FLEx group,higher postoperative values and slower recovery of tear TGF-β1,IL-1α,and TNF-αconcentrations were observed in the FS-LASIK group(P<0.01).Tear concentrations of NGF,TGF-β1,TNF-α,and IL-1αwere correlated with ocular surface changes after FLEx or FS-LASIK surgery.CONCLUSION:There is less early ocular surface disruption and a reduced inflammatory response after FLEx than after FS-LASIK.NGF,TGF-β1,TNF-α,and IL-1αmay contribute to the process of ocular surface recovery.

利用眼反应分析仪评估FS-LASIK和LASEK术后角膜生物力学稳定性

目的:利用眼反应分析仪(ORA)评估飞秒激光辅助的准分子激光原位角膜磨镶术(FS-LASIK)和准分子激光上皮下角膜磨镶术(LASEK)术后角膜生物力学稳定性的差异。方法:选取2016-01/2017-12于我院眼科视光学中心就诊且行LASEK/FS-LASIK手术的近视患者117例200眼(等效球镜-2. 00～-5. 00D),其中行FS-LASIK术者64例100眼(FS-LASIK组);行LASEK术者53例100眼(LASEK组)。分别于术前和术后1、3mo采用ORA检测两组患者的角膜滞后量(CH)和角膜阻力因子(CRF)值,并进行统计分析。结果:手术前后,两组患者CH和CRF比较,差异均有统计学意义(P<0. 05)。术后1、3mo,两组患者CH和CRF均低于术前,差异均有统计学意义(P<0. 05)。术后1mo,FS-LASIK组患者CH和CRF均低于LASEK组,差异均有统计学意义(P<0. 05)。结论:LASEK和FS-LASIK两种术式均会对角膜生物力学稳定性产生一定影响,但LASEK手术比FS-LASIK手术产生的影响更小,更安全,可减少术后屈光回退的可能性。

高度近视患者SMILE与FS-LASIK术后角膜光密度的变化

目的观察高度近视患者行飞秒激光小切口角膜基质透镜取出术(SMILE)和飞秒激光制瓣准分子激光原位角膜磨镶术(FS-LASIK)术后角膜光密度的变化规律及其意义。方法选取2018年11月至2020年11月在宁夏眼科医院行SMILE和FS-LASIK手术的高度近视患者,其中SMILE组40例40眼,FS-LASIK组41例41眼。应用Pentacam三维眼前节分析系统于术前,术后1、3、6个月以角膜顶点为中心,分别测量0~2 mm、2~6 mm、6~10 mm直径以及角膜的前、中、后及全层的角膜光密度。结果SMILE与FS-LASIK两组术后6个月不同直径及层次的角膜光密度均低于术前(P均<0.05)。两组间术后1个月6~10 mm前层及总体角膜光密度差别均具有统计学意义(P均<0.05),于术后3个月差异消失。术后1个月,FS-LASIK组0~2 mm、2~6 mm、6~10 mm前层角膜光密度与基质切削深度均存在正相关(r=0.451、0.506、0.411;P=0.004、0.001、0.009)。结论高度近视患者手术区域角膜光密度在SMILE与FS-LASIK术后早期均出现一过性上升,随着时间推移,两组角膜光密度均较术前降低。FS-LASIK组术后早期前层角膜光密度与切削深度存在正相关。

Early visual function outcomes of topography-guided FS-LASIK and SMILE in treatment of myopia and myopic astigmatism

AIM: To compare the quality outcomes of vision at early phase after topography-guided femtosecond laser-assisted in situ keratomileusis(FS-LASIK-CV) and small incision lenticule extraction(SMILE) in treatment of myopia and myopic astigmatism.METHODS: Retrospective comparative analysis of 49 patients that underwent FS-LASIK(n=23) or SMILE(n=26) procedure for myopia and myopic astigmatism between April and September in 2019. Pre-and postoperative uncorrected visual acuity(UCVA), spherical equivalent refraction(SEQ), cylindrical refraction, contrast sensitivity function(CSF), and corneal higher-order aberrations(HOAs) were evaluated. Independent t-test was used for inter-group comparison, while repeated measures ANOVA was used to analyze changes at different time points. RESULTS: In both groups, 100% of the eyes obtained a UCVA of 20/20 or better at 1 wk, 1, and 3 mo postoperatively. At 1 d and 3 mo postoperatively, UCVA was better in FS-LASIKCV group than in SMILE group. At 1 wk postoperatively, SEQ was lower in SMILE group than in FS-LASIK-CV group(P=0.006). At 3 mo postoperatively, the SEQ reached target refraction in both groups. The residual astigmatism was reduced in both groups without intergroup difference(P>0.05). At 3 mo postoperatively, the spherical aberration and coma under 6 mm pupil size were higher than preoperative levels in both groups(P<0.05). However, the increase in the corneal HOAs in the FS-LASIK-CV group was less than the SMILE group(P<0.05). At 3 mo postoperatively, the log CS were better than preoperative levels under scotopic conditions without glare and scotopic conditions with glare in both groups(P<0.05). At 1 and 3 mo postoperatively, under scotopic conditions without glare and scotopic conditions with glare, FS-LASIK-CV group showed more improvement in log CS at two spatial frequencies(12.0 c/d and 18.0 c/d;P<0.05).CONCLUSION: Both FS-LASIK-CV and SMILE demonstrate to be safe, effective, and predictable in treatment of myopia and myopic astigmatism. Early postoperative improvement in UCVA and CSF at high spatial frequency under scotopic conditions were better after FS-LASIK-CV than SMILE.

角膜屈光术后屈光稳定性及视觉质量效果评价

飞秒激光辅助的准分子激光原位角膜磨镶术(FS-LASIK)和飞秒激光小切口基质透镜取出术(SMILE)是目前主流的两种角膜屈光手术,已经过大量临床研究显示出满意的效果。FS-LASIK和SMILE两种手术相比,术后短期裸眼及矫正远视力方面均表现良好,其安全指数、有效指数、可预测性在不同研究中略有差别;在客观视觉质量方面,更多研究显示SMILE较FS-LASIK术后引入了更小的像差,且在调制传递函数和散射指数方面表现更好;而术后远期的屈光稳定性和视觉质量仍需更多的临床研究。

SMILE术中主动脱吸的合理运用和被动脱吸的原因分析及处理

目的为了指导全飞秒手术激光扫描过程中负压脱吸及潜在负压脱吸并发症的处理,保证手术顺利进行。方法回顾分析SMILE手术患者飞秒激光扫描时负压脱吸及潜在脱吸的原因及处理方法。研究中被动脱吸22只眼,5只眼为扫描透镜底层扫描进程<10%时脱吸,重新扫描;其中2只眼在激光微透镜底部切割进程>10%脱吸,终止SMILE,改为飞秒激光辅助制瓣准分子激光角膜原位磨镶术;2只眼在透镜环切时负压脱吸、9只眼为帽扫描时脱吸、4只眼为扫描切口时脱吸,启动repair程序调整参数重新扫描角膜帽。主动脱吸7只眼:其中2只眼出现扫描黑区行主动脱吸;4只眼因配合差行主动脱吸;二次SMILE补矫术中1只眼行主动脱吸。结果扫描过程中出现黑斑时主动脱吸,择日手术术后恢复良好;潜在脱吸患者,术中主动脱吸,患者情绪放松后再次扫描术后恢复良好。结论术前注视训练、宣教、稳定患者紧张情绪可有效减少被动负压脱吸。启动负压吸引前吸除眼表多余水分,清洁眼表可有效预防被动负压脱吸。全飞秒手术中预防被动脱吸,有效利用主动脱吸,处理好全飞秒激光扫描过程中的并发症,保证术后效果良好。