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Background Small incision lenticule extraction (SMILE) was a new procedure which is miniinvasion and flapless,but few attentions were paid to the visual quality after SMILE.To understand the changes of intraocular straylight after SMILE is of important significance for the assession of the visual quality after the procedure.Objective This study was to compare the characteristic of straylight between SMILE and femtosecond laser assisted laser in situ keratomileusis (FS-LAISK) after surgery.Methods A retrospective study was designed.Written informed consent was obtained from each patient prior to accepting the surgery.One hundred and twenty-seven eyes of 68 patients with myopia and myopic astigmatism were included in Tianjin Eye Hospital from January 2011 to July 2013.SMILE was performed on 64 eyes of 35 patients and FS-LASIK was carried out in 63 eyes of 33 patients at the same period.Stray light was detected with C-Quant stray light meter before and 1 week,1 month and 6 months after surgery.The changes of stray light values following the surgery were compared between the two groups,and the correlations between postoperative stray light values with operative parameters were analyzed.Results The mean stray light values were (1.03 ±0.19)D and (0.95±0.16)D at 1 week and 1 month after surgery,which were higher than (0.88 ±0.18)D at preoperation in the FS-LASIK group (P =0.000,0.012).The stray light values were (0.98±0.16),(0.95±0.14) and (0.94±0.16)D at 1 week,1 month or 6 months after surgery,and no statistically significant differences were found in comparison with (0.91 ±0.15)D in preoperation in the SMILE group (all at P＞0.05).No significant intergroup difference was seen in the stray light values (Fgroup =0.077,P=0.781).The stray light differences of various time points after surgery and before surgery were increased in the FS-LASIK group compared with SMILE group (Fgroup =14.798,P＜0.001),with the significant difference in postoperative 1 week between the two groups (P＜0.01).The negative correlations were found between stray light values at 1 week,1 month and 6 months after SMILE with the lenticule thickness/central corneal thickness (CCT) (R2=0.123,0.145,0.098,all at P＜0.05) or between stray light change.Conclusions Intraocular stray light appears less change in operative eyes after SMILE.However,intraocular stray light increases in the eyes received FS-LASIK,especially at early stage after operation.The stray light shifts return to normal with the lapse of postoperative time.
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Abstract?AlM:To investigate the influence of lOL refractive index ( Rl ) on measurement of straylight following cataract surgery.?METHODS:ln this case-control study, 77 eyes of 77 age-related cataract patients who underwent cataract phacoemulsification with posterior chamber aspherical arylic lOL implantation surgery in the Eye Hospital of China Medical University from Aug 2013 to Mar 2014, with a best corrected visual acuity ( BCVA) of 0. 5 or better, were classified into 3 groups randomly using 3 types of lOL: Tecnis ZCB00 Group ( Rl = 1. 47, 22 eyes of 22 subjects); Hoya PY60AD Group ( Rl=1. 52, 24 eyes of 24 subjects);Alcon SN60WF or lQ Group ( Rl=1. 55, 31 eyes of 31 subjects ) . BCVA, pupil size, astigmatism, axial length, intraocular straylight were measured respectively.? RESULTS: Age, axial length, BCVA, pupil size, astigmatism of the three groups were not significant difference (P>0. 05). The straylight of Tecnis, Hoya, lQ group were 1.04±0. 15, 1. 19±0. 14, 1. 14±0. 18. Straylight levels had significant differences among three groups ( F=5. 352, P = 0. 007 0. 05).?CONCLUSlON:Patients chosen the higher Rl lOL may have a higher straylight level after the surgery.
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PURPOSE: To evaluate posterior capsular opacity (PCO) using straylight and glare sensitivity meter and to compare availability of straylight and glare sensitivity with known methods for PCO evaluation. METHODS: Thirty-six pseudophakic eyes with PCO were selected for this study. Best-corrected visual acuity (BCVA), straylight (C-quant, Oculus GmbH, Wetzlar, Germany) and glare sensitivity (Binoptometer, Oculus GmbH, Wetzlar, Germany) were measured before mydriasis. After mydriasis, PCO images were captured with a slit-lamp and analyzed using the Evaluation of Posterior Capsular Opacification (EPCO) program (EPCO software, University of Heidelberg, Heidelberg, Germany). The same measurements were taken after capsulotomy and compared with pre-capsulotomy data. RESULTS: After capsulotomy, BCVA, EPCO score and straylight were improved with statistical significance (p < 0.05). Cases of PCO with mildly decreased visual acuity showed statistically significantly improved EPCO score and straylight (p < 0.05). Glare sensitivity did not show significant improvement but was statistically significantly correlated with straylight (p = 0.023, Rho = 0.732). CONCLUSIONS: Straylight is an available measurement for evaluation of PCO. Glare sensitivity meter which correlates with straylight can be used as a supportive measurement.
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Glare , Mydriasis , Visual AcuityABSTRACT
PURPOSE: To evaluate posterior capsular opacity (PCO) using straylight and glare sensitivity meter and to compare availability of straylight and glare sensitivity with known methods for PCO evaluation. METHODS: Thirty-six pseudophakic eyes with PCO were selected for this study. Best-corrected visual acuity (BCVA), straylight (C-quant, Oculus GmbH, Wetzlar, Germany) and glare sensitivity (Binoptometer, Oculus GmbH, Wetzlar, Germany) were measured before mydriasis. After mydriasis, PCO images were captured with a slit-lamp and analyzed using the Evaluation of Posterior Capsular Opacification (EPCO) program (EPCO software, University of Heidelberg, Heidelberg, Germany). The same measurements were taken after capsulotomy and compared with pre-capsulotomy data. RESULTS: After capsulotomy, BCVA, EPCO score and straylight were improved with statistical significance (p < 0.05). Cases of PCO with mildly decreased visual acuity showed statistically significantly improved EPCO score and straylight (p < 0.05). Glare sensitivity did not show significant improvement but was statistically significantly correlated with straylight (p = 0.023, Rho = 0.732). CONCLUSIONS: Straylight is an available measurement for evaluation of PCO. Glare sensitivity meter which correlates with straylight can be used as a supportive measurement.
Subject(s)
Glare , Mydriasis , Visual AcuityABSTRACT
Patients with early cataract may have normal visual acuity ( VA ) but complain that they have problems in driving at night, like seeing things through a veil. This phenomenon is defined as disability glare which maybe caused by growing stray light. Patients with intraocular lens following cataract surgery may complain about glare, halos and shadows in visual field, which are also resulted from dysphotopia. Disability glare is the VA loss due to disturbing luminance in visual field. ln other words, it's the retinal contrast sensitivity reduction because of the straylight. This article contains the consensus and new progress of disability glare. lt provides solutions according to its effect factors and offers clues for further study.
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PURPOSE: To compare visual acuity and intraocular straylight after implantation of clear and photochromic intraocular lenses (IOLs) in a mesopic lighting condition. METHODS: Clear IOLs were implanted in 95 eyes of 72 patients (clear IOL group), and photochromic IOLs were implanted in 22 eyes of 16 patients (photochromic IOL group). Best-corrected visual acuity (BCVA) was measured indoors before surgery and 1 month after surgery. Straylight values were measured indoors before surgery and 1 and 2 months after surgery using the C-quant straylight meter (Oculus GmbH, Wetzlar, Germany). RESULTS: There were no significant differences between the 2 groups in BCVA at 1 month postoperatively (p = 0.587). Mean straylight values of clear and photochromic IOL groups were 2.76 +/- 1.89 log (s) and 2.88 +/- 2.04 log (s) preoperatively, 1.39 +/- 0.84 log (s) and 1.32 +/- 0.26 log (s) at 1 month postoperatively, and 1.43 +/- 0.92 log (s) and 1.45 +/- 0.50 log (s) at 2 months postoperatively. There were no significant differences between the 2 groups in indoor straylight values (p = 0.778, 0.709, 0.929, before surgery, 1 and 2 months after surgery respectively). Repeated-measure analysis of straylight values also showed no significant difference between the 2 groups (p > 0.05). CONCLUSIONS: There were no significant differences in BCVA and straylight values between clear and photochromic IOL groups under a mesopic light condition. Therefore, photochromic IOL could be suitable choice for cataract patients who spend significant time under mesopic conditions.
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Humans , Cataract , Lenses, Intraocular , Visual AcuityABSTRACT
PURPOSE: To compare intraocular straylight between glistening-free and conventional intraocular lenses in pseudophakic eyes. METHODS: Straylight values were measured prospectively in 21 eyes with glistening-free pseudophakic lenses (group A, model enVista(TM), Bausch & Lomb, Inc., USA) and 79 eyes with conventional hydrophilic pseudophakic lenses (group B, model Akreos MI-60, Bausch & Lomb, Inc., USA). Best corrected visual acuity (BCVA) and straylight were measured preoperatively and 1 month and 2 months postoperatively using C-quant straylight meter (Oculus GmbH, Wetzlar, Germany). RESULTS: There were no statistically significant differences of BCVA preoperatively or 2 months postoperatively between the 2 groups (p > 0.05). BCVA and straylight significantly improved after the operation (p 0.05). CONCLUSIONS: In terms of straylight, glistening-free intraocular lenses were not beneficial. Although straylight was not statistically significant, other correlations between glistening and visual function should be investigated.
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Lenses, Intraocular , Prospective Studies , Visual AcuityABSTRACT
As ophthalmic science develops,the expectations of the patients undergoing cataract also advance.Good Snellen visual acuity is not always an indicator for patient's satisfaction,and the visual quality is much more important.The intraocular straylight is one of the important parameters to analyze the vision quality after surgery.The pseudophakic photic phenomena,such as dysphotopsia,is closely related to the intraocular straylight.The posterior capsular opacification,the material and the edge design of the intraocular lens (IOL),the diameter of IOL optical component are the important influential factors that cause the dysphotopsia.Great attention must be paid to it,which make us to understand the straylight deeply in order to improve postoperative visual quality.
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Background The test for visual acuity is the conventional standard for evaluating visual quality.However,there is little correlation between visual acuity and visual disability.Therefore,other clinical observations such as contrast sensitivity or straylight have been used in the clinical assessment of visual quality after cataract surgery.Objective This study was to examine the change in the amount of straylight in cataractous eyes and to evaluate the correlation of the types of cataract with visual quality.Methods A non-randomized case-controlled study was designed.Eighty eyes of 40 patients with age-related cataract were enrolled in this study,including 22 eyes with hard nucleus cataract,19 eyes with cortical cataract,23 eyes with mixed cataract and 16 eyes with posterior subcapsular cataract diagnosed based on the criteria from Lens Opacities Classification System Ⅲ(LOCS Ⅲ).The values for straylight and best corrected visual acuity (BCVA) were measured with the C-quant straylight meter and Snellen chart,respectively.The differences in the straylight values among the different types of cataract were analyzed,and the correlation of the straylight value with age or BCVA was assessed.Forty eyes of 40 age-matched normal people served as controls.Results Examination was completed in sixty-two eyes of 31 patients in the cataract group at a completion rate of 77.5％,and all the subjects in the control group finished the examination at a rate of 100％.The mean straylight value was (2.06±0.88) log in the cataract group and (1.96±0.42) log in the control group,showing a significant difference between them (t =3.251,P＜0.01).The respective mean C-quant measurements for hard nucleus cataract,cortical cataract,nuclear-cortical cataract and posterior subcapsular cataract patients were (1.96±0.42) log,(1.91 ±0.16) log,(2.05 ±0.19) log and (2.48 ±0.66) log,respectively,with a significant difference among these four groups (F =2.156,P =0.019).The highest straylight value was detected in the posterior subcapsular cataract group.The straylight value was enlarged with the increase of age with a regression equation of Y=0.0010X+ 1.025 in the hard nucleus cataract group (r =0.455,P ＜ 0.05).In addition,the negative linear correlation was found between the straylight value and BCVA in both the hard nucleus cataract group and cortical cataract group (r=-0.590,-0.697,P＜0.01).However,no correlation was found in the mixed cataract group and posterior subcapsular cataract group (r =-0.240,-0.235,P＞0.05).Conclusions The C-quant straylight meter can objectively reflect the visual function for hard nucleus and cortical cataractous eye.Posterior subcapsular cataract produces straylight and exerts a great influence on visual quality due to early glare sensation,so it should be benefit to perform surgery earlier.
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BackgroundIn an ideal eye there would be no light scattering at all,but the eye media is not optically ideal.Intraocular straylight causes a veil of light and reduction in the contrast of the retinal image and thus decrease the quality of vision.ObjectiveThe present study was to investigate the repeatability and reproducibility of C-Quant straylight meter( Oculus,Germany)in measuring retinal straylight of myopia and post-laser in situ keratomileusis(LASIK) corneas.MethodsThis is a prospective research.The consecutive 35 eyes of 21 myopic patients and 34 eyes of 22 patients who received LASIK were included in this trail.Retinal straylight was measured for 7 times at a period of time and analyzed quantificational to evaluate the repeatability of measurement.Thirty-eight eyes of 19 patients were measured again at 3-7 days for 3 times at a period of time to assess the reproducibility of C-Quant straylight meter.The mean standard difference (SD) and coefficient of variation (CV) were used as the credibility evaluation.This clinical study complied with Helsinki Declaration and the informed consent was obtained prior to the medical procedure.ResultsThe straylight Log(s) of 7 times measurement were all less than 0.95.The mean Log(s) were 0.92±0.12 and 0.93±0.17 respectively in myopia group and post-LASIK group,without statistically significant differences among 7 times measurement( F=0.335,P=0.812;F=1.000,P=0.409).The mean SD for the 7 times measurement was 0.07 Log units.SD and CV increased with the number of measurements.The differences of mean SD and CV between 3 times result and 6 times result were significant different (t =-2.080,P =0.045;t =-2.190,P =0.035 ).No difference was found between different time periods( t =-0.531,P=0.598 ).The difference of the results between two measurements from the same patient was 0.013.ConclusionsC-Quant is a noncontact,noninvade,rapid and convenient method for the measurement of straylight in myopia and post-LASIK eyes due to the high repeatability and reproducibility.
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PURPOSE: To compare intraocular straylight in normal and cataractous eyes as the morphology and to compare straylight as the result of subjective symptoms in early cataract cases using the C-quant straylight meter, the only tool to measure light scattering in media. METHODS: Straylight values were measured in 217 normal eyes and 138 cataractous eyes. Cataractous eyes were classified into posterior subcapsular opacity, anterior subcapsular opacity and nucleosclerosis. Straylight values of each group were measured. The 56 early cataractous eyes were categorized into two groups, depending on the presence of subjective symptoms, and each straylight value was measured. The preoperative and postoperative straylight values of early cataracts were also compared. RESULTS: The mean straylight values of normal and cataractous eyes were 1.34 and 2.46, respectively. The value of posterior subcapsular opacity (2.81) was significantly higher than that of anterior subcapsular opacity (2.33) and nucleosclerosis (1.99). The straylight values of early cataracts were significantly higher in the group with subjective symptoms (2.02) than in the group without subjective symptoms (1.56). The postoperative straylight value decreased to 1.42. CONCLUSIONS: The posterior subcapsular cataract showed significantly high intraocular straylight, indicating that light scattering occurred to a greater extent in this group. Light scattering occurred more in early cataractous eyes with subjective symptoms than in eyes without symptoms, and light scattering was reduced after surgery. The C-quant straylight meter, which measures the light scattering in media, can be a useful tool to determine the time of cataract surgery and to evaluate the quality of vision.
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Cataract , Eye , Light , Vision, OcularABSTRACT
Objective To compare the stray-light effects caused by different parts of optic edge of 7 intraocular lens(IOL)edge designs.Methods Monochromatic laser beam was used to illuminate the upper edge and complex of three-piece and single-piece IOLs at several angles of incidence.Light images produced in the retinal plane were photographed with a digital camera.The differences in the light images were compared between three-piece and single-piece IOLs.Results There were differences in light images between 2 groups,which may be due to different shapes of edge design when the upper edge of IOL was illuminated.Three-piece IOL exhibited line images or dense patch,which differed with single-piece IOL when the complex of IOL was illuminated.Conclusion Both edge shape and irregular structure in three-piece IOL complex may be important factors for postoperative glare in pseudophakic patients.