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AIM: To study the patient characteristics and keratorefractive surgery(KRS)practice in central India.METHOD: The retrospective study was conducted on 410 patients who underwent KRS from June 2017 to April 2022 at a tertiary eye care center in central India. Demographic data of the patients presenting for the spectacle free vision like age, sex, residence in the form of urban or rural area, refractive error, cause for spectacle-free vision, best-corrected visual acuity, types of procedure, postoperative follow-up and complications were recorded.RESULTS: Among the 410 patients who presented for spectacle-free vision, 324 patients were considered for KRS(79.0%), and 200 patients(61.7%)underwent the laser-assisted in situ keratomileusis(LASIK)procedure, whereas 124 patients(38.3%)underwent the photorefractive keratectomy(PRK)procedure. The final study group comprised 179 female and 145 male. The mean age of the patients was(25±3.5)years. A majority of patients were from urban areas(n=250, 77.2%). The mean preoperative manifest refraction in the right and left eyes was -4.5±2.1 and -4.9±2.0, respectively. The mean surgical time in the LASIK patient was(15±2)min and(17±3)min for both eyes in PRK. None of the patients exhibited epithelial ingrowth, flap healing complications, or infection, and none of them required enhancement. Suboptimal corneal thickness(n=28, 32.6%)was the most common reason for rejection. At the end of the 1-year follow up, 3 patients who underwent the LASIK procedure exhibited regression(-0.5 D±1 D), with a refractive error correction of -6.75 D, -8.5 D, and -7.0 D, respectively.CONCLUSION: LASIK is the predominant procedure for the correction of refractive error in the central Indian population. Although the number of PRK procedures was small, both LASIK and PRK exhibited excellent visual outcome. Myopic regression should be considered when choosing LASIK for high myopia.
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Objective:To compare the changes in functional optical zone (FOZ) and corneal morphology in myopes between femtosecond small incision laser lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK).Methods:A cohort study was performed.A total of 94 patients (94 eyes) who underwent FS-LASIK or SMILE at Eye Hospital, Wenzhou Medical University from March to December 2021 were enrolled.The selected patients were divided into a SMILE group (46 cases, 46 eyes) and an FS-LASIK group (48 cases, 48 eyes) according to the surgical procedure, and the follow-up period was 6 months.The primary outcome measures were postoperative changes in corneal FOZ and Q-value, and the secondary outcome measures were changes in central corneal thickness (CCT) and mean corneal curvature (Km). Corneal Q-value, horizontal and vertical FOZ diameters, CCT, and Km were recorded before surgery and at 1 day, 1 week, 1 month, and 6 months after surgery using the Pentacam anterior segment analysis system, and the differences in each parameter and the trends of changes between the two groups were compared.This study adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Eye Hospital, Wenzhou Medical University (No.2021-034-k-27). Written informed consent was obtained from each subject.Results:There were statistically significant overall differences in the postoperative horizontal and vertical FOZ diameters between the two groups (horizontal diameter: Fgroup=7.06, P<0.001; Ftime=64.18, P=0.001; vertical diameter: Fgroup=11.08, P<0.001; Ftime=77.14, P<0.001). The horizontal and vertical FOZ diameters were significantly larger in SMILE group than in FS-LASIK group at various postoperative time points, and the differences were statistically significant (all at P<0.001). In the two groups, the postoperative 1-week, 1-month and 6-month horizontal FOZ diameters and the postoperative 1-week and 1-month vertical FOZ diameters were smaller than the postoperative 1-day ones, and the differences were statistically significant (all at P<0.05). There were significant overall differences in Q-values at different postoperative time points between the two groups ( Fgrouup=53.11, P=0.019; Ftime=29.18, P<0.001). The postoperative 1-day, 1-week, and 1-month Q-values of FS-LASIK group were significantly higher than those of SMILE group (all at P<0.05). The postoperative 1-week Q-value was significantly larger than the postoperative 1-day value in SMILE group ( P<0.001). The postoperative Q-values gradually decreased with time in FS-LASIK group, with significant pairwise differences at all adjacent time points (all at P<0.001). There were significant differences in CCT at various postoperative time points between the two groups ( Ftime=21.43, P<0.01). In FS-LASIK group, the CCT was decreased at 1 week than 1 day after surgery and was increased at 6 months than 1 week after surgery, and the differences were statistically significant (all at P<0.05). In SMILE group, the postoperative 1-week, 1-month and 6-month CCT was increased in comparison with the postoperative 1-day value, and the differences were statistically significant (all at P<0.05). There was no significant overall difference in the Km between the two groups ( Fgroup=27.29, P=0.41). There were significant pairwise differences in the Km at different postoperative time points between the two groups (all at P<0.001). The postoperative 6-month Km was smaller than the postoperative 1-day value in SMILE group, and the postoperative 6-month Km was greater than the postoperative 1-day value in FS-LASIK group (both at P<0.05). Conclusions:The FOZ shows a trend of gradual reduction within a month after SMILE and FS-LASIK.The FOZ is larger after SMILE than after FS-LASIK.The morphologic stability of corneal FOZ is better after SMILE than after FS-LASIK.
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Aim: This study was aimed to assess the knowledge, attitude and practices regarding refractive error correction surgeries among undergraduate medical students.Study Design: In this study cross-sectional study design was used.Duration and Place of Study: The study was conducted amongst the undergraduate MBBS students studying at Dow Medical College, Karachi. The duration of study was seven months (August, 2019 till February, 2020).Methods: A sample size of 189 was calculated for the study with confidence level 95% and confidence limit 5%. Data was collected through a validated self-administered questionnaire which was divided in five subsections used to gain information regarding participant抯 demographics, knowledge, attitude and practices regarding refractive error surgeries. Data was analyzed using IBM SPSS V.22.Results: In our study 189 students with a mean age of 21�8 years were included. Among the participants 112 (59.3%) had refractive errors. Glasses were used by majority 76 (67.9%) of participants for visual correction. Use of refractive error correction methods at all times was reported by 72 (66.7%) participants. Majority of respondents 142 (75.5%) had heard about surgery being used for correction of refractive errors. A large number of students 117 (66%) refused for surgery and fear of the outcomes was one of the reason for this refusal.Conclusion: We found that majority of the participants were aware about refractive error correction surgeries yet most of them showed unwillingness for these procedures. This negative attitude must be changed to positive in order to enhance the practice for these procedures.
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We describe a modified technique of intraoperative optical coherence tomography (iOCT)?guided removal of post?laser?assisted in situ keratomileusis (LASIK) epithelial ingrowth with interface ethyl alcohol and mitomycin C application to prevent a recurrence. Epithelial ingrowth was visualized as hyperreflective deposits in the interface on iOCT, and the location and extent were noted at the beginning of the procedure. A simple dimple?down maneuver was performed to help identify the circumference of the LASIK flap. iOCT helped to delineate the flap edge and ensure dissection in the correct plane with complete removal of epithelial cell nests. Real?time visualization of the interface helped in on?table decision making regarding the extent of lifting the flap to encompass the entire region of hyperreflective epithelial ingrowth, as well as the need for additional interventions to ensure complete flap apposition at the end of surgery. All patients gained an uncorrected visual acuity of 20/20–20/25 with no recurrence
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The decrease of corneal stiffness is the key factor leading to keratoconus, and the corneal collagen fiber stiffness and fiber dispersion are closely related to the corneal biomechanical properties. In this paper, a finite element model of human cornea based on corneal microstructure, namely collagen fiber, was established before and after laser assisted in situ keratomileusis (LASIK). By simulating the Corvis ST process and comparing with the actual clinical results, the hyperelastic constitutive parameters and corneal collagen fiber stiffness modulus of the corneal material were determined before and after refractive surgery. After LASIK, the corneal collagen fiber stiffness modulus increased significantly, and was highly correlated with central corneal thickness (CCT). The predictive relationship between the corneal collagen fiber stiffness modulus and the corresponding CCT before and after surgery was: = exp(9.14 - 0.009CCT ), = exp(8.82 - 0.008CCT ). According to the results of this study, the central corneal thickness of the patient can be used to estimate the preoperative and postoperative collagen fiber stiffness modulus, and then a personalized corneal model that is more consistent with the actual situation of the patient can be established, providing a theoretical reference for more accurately predicting the safe surgical cutting amount of the cornea.
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Humans , Biomechanical Phenomena , Cornea , Corneal Topography , Finite Element Analysis , Keratomileusis, Laser In Situ , MyopiaABSTRACT
@#AIM: To investigate and compare the effect of femtosecond laser-assisted <i>in situ</i> keratomileusis(FS-LASIK)and small incision lenticule extraction(SMILE)surgery on anterior corneal asphericity.<p>METHODS: There were sixty eyes of 60 patients in FS-LASIK and SMILE group respectively from November 2016 to September 2017. The Q-values of anterior corneal surface for different diameters(6, 7, 8 and 9mm)and corneal aberrations were measured with Pentacam before and 3mo after operation.<p>RESULTS: The Q-values of anterior corneal surface between FS-LASIK and SMILE were no significant differences. After 3mo operation, the values increased significantly; and the post-operative Q-values of 6mm in group SMILE was significant lower than group FS-LASIK(0.47±0.32 <i>vs</i> 0.89±0.43,<i>P</i><0.05). The higher aberration and spherical aberration in FS-LASIK and SMILE were no significant differences before surgery; after 3mo operation,there were no significant difference between them. However, group FS-LASIK had significant higher spherical aberration than group SMILE(0.43±0.23μm <i>vs</i> 0.31±0.11μm, <i>P</i><0.05).<p>CONCLUSION: FS-LASIK and SMILE cause significant changes of anterior corneal asphericity, Q-values all increased to positive values after surgeries; and there have less changes of Q-value and corneal aberration in SMILE than in FS-LASIK surgery.
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PURPOSE: To evaluate the efficacy of 3% diquafosol tetrasodium (DQ) after laser-assisted in-situ keratomileusis (LASIK). METHODS: This prospective randomized study included 150 eyes in 75 patients who were scheduled for LASIK. The patients in the 3% diquafosol tetrasodium (DQ) group (37 patients, 74 eyes) were instructed to apply one drop of DQ, six times daily post-op, while the patients in the 0.3% sodium hyaluronate (HA) group (38 patients, 76 eyes) were instructed to apply one drop of HA, six times daily post-op. A Schirmer test, tear film break-up time (BUT), corneal and conjunctival fluorescein staining score (FLSS), and ocular surface disease index (OSDI) were evaluated pre-op and at 1, 4, and 12 weeks post-op while the tear osmolarity was evaluated pre-op and at 4 and 12 weeks post-op. RESULTS: There was no significant difference between the two groups regarding Schirmer test results or tear osmolarity and conjunctival FLSS. The BUT was significantly higher in the DQ group at 1 week and 12 weeks post-op. The corneal FLSS was significantly lower in the DQ group at 1 week, 4 weeks and 12 weeks post-op. The OSDI was significantly lower in the DQ group at 1 week post-op. CONCLUSIONS: Use of 3% diquafosol tetrasodium after surgery improved ocular dryness and increased the tear film stability.
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Humans , Fluorescein , Hyaluronic Acid , Keratomileusis, Laser In Situ , Osmolar Concentration , Prospective Studies , TearsABSTRACT
PURPOSE: To report a case of irregular astigmatism caused by a free flap during laser-assisted in situ keratomileusis (LASIK) surgery that was treated with a flap rotation based on postoperative topography. CASE SUMMARY: A 21-year-old female underwent LASIK, which was complicated by a free cap on her right eye. Because the gentian violet markings were no longer present, the exact orientation of the cap was unknown. At 3 months after surgery, the astigmatism of the right eye was −3.00 diopters (D) with an uncorrected visual acuity (UCVA) of 0.4, and the astigmatism of the left eye was −0.75 D with an UCVA of 1.0. The corneal topography was analyzed in order to return to the existing position. Free cap repositioning was performed and irregular astigmatism was corrected to improve the UCVA to 1.0. CONCLUSIONS: If the preoperative markings cannot be identified on a free flap during LASIK, secondary postoperative corneal topographic analysis can be performed to restore the corneal free flap to its original position to minimize astigmatism with good visual outcomes.
Subject(s)
Female , Humans , Young Adult , Astigmatism , Corneal Topography , Free Tissue Flaps , Gentian Violet , Keratomileusis, Laser In Situ , Visual AcuityABSTRACT
AIM:To assess the changes in higher order aberrations after wavefront guided femtosecond laser assisted laser in situ keratomileusis ( FS-LASIK ) for moderate to high astigmatism.?METHODS: Eighty-eight eyes of 50 myopia patients with moderate to high astigmatism were included in this prospective study. There were 51 eyes with moderate astigmatism (≥-1. 50D and <-3. 00D) and 37 eyes with high astigmatism (≥-3. 00D). All patients underwent wavefront guided FS-LASIK. Uncorrected distance visual acuity ( UDVA ) , corrected distance visual acuity (CDVA), keratometry, central corneal thickness ( CCT)and higher order aberrations ( HOAs ) were evaluated before operation and 3mo postoperatively.?RESULTS:At the 3mo after operation, the mean UDVA of all eyes was above 20/20, better than before operation (P<0. 05), but CDVA remained unchanged (P=0. 36) and no eyes lost ≥2 lines of CDVA. Mean astigmstism of 85 eyes ( 97％) was reduced below - 1. 00D, mean astigmatism of 70 eyes ( 80％) was reduced below-0.50D(P<0. 05). The average corneal curvature was flatter by 3. 81 ± 1. 97D and CCT was reduced by 78. 66 ± 37. 22μm, postoperatively (P<0. 05). Coma and trefoil aberrations remained unchanged(P=0. 078, 0. 065). The spherical aberration, secondary astigmatism and the HOA root mean square ( RMS ) increased from 0. 19 ± 0. 06, 0.05±0. 02 and 0. 42±0. 12, preoperatively to 0. 32± 0. 17, 0. 26 ± 0. 08 and 0. 78 ± 0. 28 ( P < 0. 05 ), postoperatively.?CONCLUSION: Wavefront-guided FS-LASIK is a safe and effective option for the patients with moderate to high astigmstism although parts of HOAs increased.
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AIM: To investigate the changes of corneal biomechanical indexes after femtosecond laser-assisted in situ keratomileusis ( LASIK ) , so as to provide theoretical basis for the safety study of femtosecond laser LASIK.?METHODS: Totally 85 myopia patients ( 170 eyes ) treated in our hospital from June 2014 to June 2016 were selected and underwent femtosecond laser LASIK surgery. The medical records of patients met the inclusion criteria were retrospectively analyzed. Corneal compensated intraocular pressure ( IOPcc ) and corneal resistance factor ( CRF ) , corneal hysteresis ( CH ) and Goldmann correlated to IOP value ( IOPg ) before operation, and at 3 and 6mo after surgery were measured by the ocular response analyzer, and central corneal thickness was measured by A type ultrasonic measuring instrument.?RESULTS:At postoperative 3 and 6mo, central corneal thickness was sharply lower than that before surgery, with a statistical significance ( P<0. 05 ); postoperative IOPcc, CRF, CH, IOPg and other corneal biomechanical parameters decreased distinctively, with statistical meaning ( P<0. 05 ); data at postoperative 3 and 6mo showed no evident differences ( P>0. 05 ); the cornea cutting thickness was 98. 67 ± 7. 56μm, CH and CRF variation were 3. 40 ± 0. 34mmHg, 3. 55 ± 0. 43mmHg respectively, the cornea cutting thickness was positively correlated with CH, CRF variation ( r=0. 232, 0. 254; P<0. 001).? CONCLUSION: Femtosecond laser LASIK can apparently reduce corneal thickness as well as the corneal biomechanical indexes, the data at postoperative 3mo tends to be stable.
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@#AIM: To compare the difference of biomechanical stability after a femtosecond laser-assisted <i>in situ</i> keratomileusis(FS-LASIK)and laser-assisted subepithelial keratomileusis(LASEK)by ocular response analyzer(ORA). <p>METHODS: This prospective study was conducted at the First Affiliated Hospital of Harbin Medical University, and myopic patients with the equivalent sphere between -2.00 and -5.00 diopters from January 2016 and December 2017 were enrolled. All the subjects were divided into FS-LASIK and LASEK group respectively according to different surgical methods. There were 64 patients(100 eyes)participated in the FS-LASIK group while 53 patients(100 eyes)in the LASEK surgery group. Corneal hysteresis value(CH)and corneal resistance factor value(CRF)were measured pre-, 1mo and 3mo postoperation of all the subjects. And the variance analysis of two groups was repeated to compare the overall difference between the two modes of operation from pre-operation to post operation. <p>RESULTS: The CH and CRF value of the two groups were different before and after operation(<i>P</i><0.05). The comparison results of repeated measurements showed that the CH value and CRF value of the surgical methods were reduced in 1 and 3mo after operation, respectively, and there was significance(<i>P</i><0.05). The CH and CRF of FS-LASIK group was lower than LASEK group only in 1mo after the operation(<i>P</i><0.05). <p>CONCLUSION: Both surgeries could affect the biomechanical stability of cornea. From the point of view of biomechanical stability, LASEK operation is safer than FS-LASIK operation and reduces the possibility of postoperative refractive regression.
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·AIM:To study the influence factors and management of anterior chamber gas bubble during femtosecond flap creation for laser-assisted in situ keratomileusis ( LASIK) .·METHODS: Totally 9671 eyes of 4859 patients with femtosecond LASIK were included in this study. Preoperative, intraoperative and postoperative parameters of anterior chamber gas bubble patients were analyzed and compared.·RESULTS:A total of 51 cases (0. 53%) occurred anterior chamber gas bubble during femtosecond flap creation. There was no statistical difference between uncorrected visual acuity of postoperative 1mo (-0. 076 ± 0. 09 ) and preoperative best corrected visual acuity (-0. 08±0. 04; t=-0. 34,P=0. 74). And 33 eyes (65%) did not affect the pupil tracking, but there were 18 eyes ( 35%) unable to track the pupil successfully. There was no statistical difference in uncorrected visual acuity of postoperative 1mo between trace group (-0. 06 ± 0. 08 ) and no trace group(-0. 11 ± 0. 09; t = 1. 82, P = 0. 07). The highest incidence of anterior chamber gas bubble was at 9 point, followed by 3 point. There were no statistical differences in spherical equivalent refraction, corneal curvature, corneal diameter, anterior chamber volume, anterior chamber depth and intraoperative femtosecond laser energy between anterior chamber gas bubble eyes and the contralateral eyes (P>0. 05).·CONCLUSION: Anterior chamber gas bubble formation during femtosecond flap creation for LASIK is an uncommon event. It may affect the eye tracking. There is no obvious effect on early postoperative visual acuity if intraoperative disposed properly. The direct or indirect factors of anterior chamber gas bubble formation are unclear.
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Objective To observe the clinical outcomes of corneal collagen cross-linlIng (CLX) and laser-assisted in situ keratomileusis (LASIK) for refractive error.Methods Together 100 patients (200 eyes) with myopia and/or astigmatism who underwent LASIK were admitted from December 2015 to January 2016,and divided into treatment group (50 patients,100 eyes),in which patient received CXL-LASIK,and control group (50 patients,100 eyes),in which the controls were given LASIK alone.Then the optical variables,including visual acuity,diopter,cornea endothelium cell counting,corneal transparency,corneal collagen cross-linking line,were examined and analyzed before operation and 1 week,1 month,3 months,6 months and 12 months after opera tion.Results As for postoperative time points,the uncorrected visual acuity after operation was better than the best corrected visual acuity before surgery in the two groups,but the differences in diopter between the two groups were statistically significant (all P ＜ 0.05).There was no significant difference in diopter 1 month and 12 months postoperatively in the treatment group (t =0.021,P =0.070),while its difference in the control group 1 month and 12 months postoperatively(t =4.857,P =0.010).The differences of the cornea endothelium cell counting in the treatment group between before and after surgery were not statistically significant (F =1.163,P =0.327).Moreover,slightly opacification apPeared in anterior corneal stromal in the early stage after surgery in the treatment group,and the average thickness of corneal collagen cross-linking line was 210.00-340.00 (270.48 + 37.80) μm 1 month postoperatively,accounting for 63％ of the central cornea thickness.There were not flap-related complications in the treatment group,but the control group had corneal flap wrinkle in 3 eyes and displacement in 1 eye in the controls.Conclusion Corneal collagen cross-linlIng and laser-assisted in situ keratomileusis for refractive error can obtain better outcomes,including sound uncorrected visual acuity and stable diopter after surgery,without the loss of the corneal endothelial cells.
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Objective To observe the clinical outcomes of corneal collagen cross-linlIng (CLX) and laser-assisted in situ keratomileusis (LASIK) for refractive error.Methods Together 100 patients (200 eyes) with myopia and/or astigmatism who underwent LASIK were admitted from December 2015 to January 2016,and divided into treatment group (50 patients,100 eyes),in which patient received CXL-LASIK,and control group (50 patients,100 eyes),in which the controls were given LASIK alone.Then the optical variables,including visual acuity,diopter,cornea endothelium cell counting,corneal transparency,corneal collagen cross-linking line,were examined and analyzed before operation and 1 week,1 month,3 months,6 months and 12 months after opera tion.Results As for postoperative time points,the uncorrected visual acuity after operation was better than the best corrected visual acuity before surgery in the two groups,but the differences in diopter between the two groups were statistically significant (all P ＜ 0.05).There was no significant difference in diopter 1 month and 12 months postoperatively in the treatment group (t =0.021,P =0.070),while its difference in the control group 1 month and 12 months postoperatively(t =4.857,P =0.010).The differences of the cornea endothelium cell counting in the treatment group between before and after surgery were not statistically significant (F =1.163,P =0.327).Moreover,slightly opacification apPeared in anterior corneal stromal in the early stage after surgery in the treatment group,and the average thickness of corneal collagen cross-linking line was 210.00-340.00 (270.48 + 37.80) μm 1 month postoperatively,accounting for 63％ of the central cornea thickness.There were not flap-related complications in the treatment group,but the control group had corneal flap wrinkle in 3 eyes and displacement in 1 eye in the controls.Conclusion Corneal collagen cross-linlIng and laser-assisted in situ keratomileusis for refractive error can obtain better outcomes,including sound uncorrected visual acuity and stable diopter after surgery,without the loss of the corneal endothelial cells.
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AIM:To investigate the effect of different cutting centers on the visual acuity, refractive diopter and visual quality of patients undergoing laser assisted in situ keratomileusis (LASIK).METHODS: A total of 80 patients (160 eyes) with myopia treated by elective LASIK were divided into two groups.Thirty-six cases (72 eyes) with visual axis corneal reflection point (VACRP) as the cutting center were included into the VACRP group while 44 cases (88 eyes) with pupil center (PC) as the cutting center were included into the PC group.The uncorrected visual acuity (UCVA), the best corrected visual acuity (BCVA), refractive diopter, corneal aberration [total corneal and anterior corneal surface higher-order aberrations (HOA), spherical aberration (Z40), vertical coma (Z3-1), horizontal coma (totZ31) and offset of cutting centers were determined before surgery and 1mo after surgery.RESULTS: There was no difference in the probability of UCVA ≥ 0.1, BCVA and refractive diopter between the two groups at 1mo after surgery (P>0.05).The astigmatism and cutting center deviation of VACRP group were lower than those of PC group (P<0.05).The totHOA, totZ40, totZ3-1, totZ31, froHOA, froZ3-1、froZ31 and froZ40 were lower in VACRP group than PC group at 1mo after surgery (P<0.05).CONCLUSION: The UCVA of patients treated with both cutting centers for LASIK is good but VACRP has more advantages in reducing the offset of cutting center and improving postoperative visual quality.
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AIM: To study the visual quality, dry eye and biomechanical stability of patients with myopia and astigmatism after different corneal refractive surgeries. ·METHODS: A total of 986 patients with myopia and astigmatism were selected as the research object in our hospital from July 2015 to July 2016, according to the operation mode of the selection of the research object, the 986 patients were randomly divided into small incision lenticule extraction ( SMILE) group, femtosecond laser in situ keratomileusis ( FS-LASIK ) group, sub-bowman-keratomileusis ( SBK ) group and laser-assisted in situ keratomileusis ( LASIK ) group. The postoperative visual quality was determined by comparing the diopter, uncorrected visual acuity ( UCVA ) , best corrected visual acuity ( BCVA) and high-order image difference of 25d, 90d. The postoperative dry eye condition was determined by comparing the postoperative tear secretion test ( Schirmer Ⅰ test ) , tear film rupture time ( BUT ) and fluorescence staining ( FS) . The biomechanical stability of the patients was determined by comparing the corneal hysteresis ( CH ) and corneal resistance factor ( CRF ) values of the four groups. ·RESULTS: The diopter, UCVA, BCVA and high-order aberration comparison of FS-LASIK group, SBK group and LASIK group between before and after surgery, showed no significant difference ( P>0. 05 ); on diopter, BCVA, UCVA, there was no significant difference between before and after surgery in SMILE group (P>0. 05), but statistical significance difference on high order aberration (P<0. 05). The BUT and FS value of the four groups decreased obviously after operation, and the difference was statistically significant (P<0. 05). In LASIK group SIt after operation significantly decreased, with statistically significant compared with that before operation ( P <0. 05). After operation, CH and CRF of the four groups decreased with significant differences (P<0. 05). ·CONCLUSION: SMILE, FS-LASIK, SBK and LASIK are equally safe, effective and stable in the treatment of myopia and astigmatism.
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PURPOSE: We present a case of a patient who underwent corneal refractive surgery to improve their corrected visual acuity due to a complication of hyperopic laser-assisted in-situ keratomileusis (LASIK). CASE SUMMARY: The patient complained of decreased vision after hyperopic LASIK surgery 12 years prior. The corrected distance visual acuity (CDVA) was 20/200 in the right eye and 20/32 in the left, with manifested refractions of +1.25 +2.00 × 90 and -0.25 +2.00 × 80, respectively. The patient had a with-the-rule astigmatism. The values of corneal and total spherical aberration, which can be determined as coefficients of the Zernike polynomials, were respectively -1.027 µm and -0.773 µm in the right eye and -0.965 µm and -0.881 µm in the left eye. Slit lamp biomicroscopy revealed no remarkable findings. We performed surface ablation surgery to flatten the central cornea of the patient's right eye. At 12 months after surgery, the CDVA of the patient's right eye was 20/30 and the negative corneal spherical aberration was reduced. CONCLUSIONS: Corneal refractive surgery to reduce negative corneal spherical aberration by flattening the central cornea is one of possible treatment options for the reduced corrected distance visual acuity after hyperopic LASIK.
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Humans , Astigmatism , Cornea , Keratomileusis, Laser In Situ , Patient Rights , Refractive Surgical Procedures , Slit Lamp , Visual AcuityABSTRACT
PURPOSE: To evaluate the effect of combined medical treatment with anti-glaucoma eyedrops and 0.1% fluorometholone on visual acuity and refractive errors in patients complaining of blurred vision due to myopic regression after laser-assisted in-situ keratomileusis (LASIK) or laser-assisted sub-epithelial keratectomy (LASEK). METHODS: This study comprised 155 patients (155 eyes) who were diagnosed with myopic regression after LASIK or LASEK and received medical treatment from January 2015 to January 2016. The visual acuity and refractive errors were compared before and after medical treatment and evaluated to determine whether the results differ between LASIK and LASEK. RESULTS: The mean time of medical treatment was 64.1 ± 36.8 months after surgery. The responder group whose vision was improved and whose myopic error was decreased after medical treatment was comprised of 63 patients (41%). Their visual acuity in this group improved -0.21 ± 0.11 logMAR, and the amount of myopic error decreased 0.56 ± 0.32 diopters. The full responder group was 24 patients (15%), and the partial responder group was 39 patients (26%). The frequency of response to medical treatment was higher after LASIK than after LASEK, but the difference was not statistically significant. CONCLUSIONS: The combined medical treatment with anti-glaucoma eyedrops and 0.1% fluorometholone was effective in 41% of patients with regard to visual acuity improvement when used for post-LASIK or post-LASEK myopic regression. The medical treatment was effective after both LASIK and LASEK.
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Humans , Fluorometholone , Keratectomy, Subepithelial, Laser-Assisted , Keratomileusis, Laser In Situ , Ophthalmic Solutions , Refractive Errors , Visual AcuityABSTRACT
?AIM: To study correcting effect and visual quality after laser - assisted in situ keratomileusis ( LASIK ) with femtosecond and posterior chamber intraocular lens ( ICL) implantation in high myopia patients.?METHODS: Fifty-five patients ( 106 eyes ) with high myopia from February 2012 to February 2015 in our hospital were analyzed. According to the different operation, patients were divided into the observation group( using ICL implantation, 27 cases with 53 eyes) and the control group (using LASIK, 28 cases with 53 eyes). Postoperative follow-up was 1a, to observe and analyze the visual quality, higher order aberration and complications of two groups.?RESULTS: Uncorrected visual acuity ( UCVA ) , the best corrected visual acuity ( BCVA ) , effectiveness index and security index at 1a postoperatively of observation group, were 1. 04±0. 86(LogMAR), 0. 97±0. 19(LogMAR), 104. 69± 18. 56, 108. 79 ± 17. 68, significantly higher than those of control group 0. 78 ± 0. 11 ( LogMAR ), 1. 04 ± 0. 09 (LogMAR), 93.78±15. 65, 100. 71±11. 68 (P 0. 05 ). No severe complications were observed in both groups.?CONCLUSION: LASIK with femtosecond and ICL lens implantation can effectively improve the patient’s visual quality, but for patients with high myopia, ICL lens implantation effect is more significant, the safety index of ICL implantation, as well as the effectiveness index and the visual quality are better than those of LASIK.
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LASIK is the most popular treatment method for correction of the refractive errors of ophthalmology its development in 1990 and number of patients has continued to increase.The safety and efficacy of LASIK surgery have been reported several times by numerous researchers and doctors, but all studies have made abroad. This time we have summarized postoperative outcomes of LASIK surgery, which have performed in our country. Consequently 103 patients (206 eyes) who underwent LASIK surgery in “Bolor-Melmii” eye clinic between 2007 and 2011 were enrolled. The retrospective method of study was used to evaluate postoperative outcomes. Preoperative UCVA of 0.04-0.4 improved to 0.5-1.2(decimal) at 1 day after surgery and during 1 year after surgery revealed minimal but wasstable. Preoperative mean sphere equivalent of 2.2+/-0.72D improved at the 1 year by +/-0.5D in 161 eyes (78.15%), by +/-1.0D in 39 eyes (18.9%) and by +/-2.0D in 6 eyes (2.9%)after surgery. Mean sphere equivalent and astigmatism improved to -0.46 +/-0.4D and -0.43+/-0.34D respectively at 1 year after surgery. Improvement of the sphere equivalent and its stability during a year period of study proves that LASIK surgery is an effective with stable improvements and safe procedure for correcting myopia/myopic astigmatism. No severe complications occurred during and after surgery.