results on the comparison of visual … 360-degree square edge to prevent lens epithelial cell...

moksliniai tyrimai

48

Paulius RudalevičiusLietuvos sveikatos mokslų universitetoMedicinos akademijos Akių ligų klinikaEivenių g. 2, [email protected]

teorija ir praktika 2014 - T. 20 (Nr. 1), 48–58 p.

RESULTS ON THE COMPARISON OF VISUAL FUNCTION OUTCOMES WITH FOUR DIFFERENT MULTIFOCAL INTRAOCULAR LENSES

KETURIŲ SKIRTINGŲ DAUGIAŽIDININIŲ INTRAOKULINIŲ LĘŠIŲ SUKELTŲ REGĖJIMO FUNKCIJŲ PALYGINIMAS

Paulius Rudalevičius¹, Ugnė Rumelaitienė¹, Tanja M. Rabsilber², Gerd U. Auffarth², Vytautas Jašinskas¹

¹Department of Ophthalmology, Lithuanian University of Health Sciences, Medical Academy, Lithuania²Department of Ophthalmology, University of Heidelberg, Germany

¹Lietuvos sveikatos mokslų universiteto Medicinos akademijos Akių ligų klinika²Heidelbergo universiteto (Vokietija) Akių ligų klinika

ABSTRACTKey words: multifocal intraocular lenses, IOL, cataract, presbyopia, visual acuity.Purpose. To assess the visual outcomes after cataract surgery with the implantation of four different model multifocal in-traocular lenses (IOL).Setting. Department of Ophthalmology, Lithuanian University of Health Sciences, Medical Academy, Lithuania.Methods. This prospective study evaluated the visual outcomes over a 6 month follow–up period after cataract surgery with bilateral implantation of the following multifocal IOLs: Rayner M-flex (M-flex), TECNIS ZMB00 (TECNIS), Acrysof ReSTOR (ReSTOR) and AT.LISA tri 839 MP (AT.LISAtri). Monocular and binocular LogMAR uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected near visual acuity (UNVA), corrected near visual acuity (CNVA), and uncorrected intermediate visual acuity (UIVA) were recorded. The spectacle independence and photic phenomena were assessed.Results. The study involved a total of 170 eyes of 85 patients. There was no statistically significant UDVA and CNVA dif-ference (p = 0.18) between the multifocal implants six months after the sugery. The CDVA was significantly better after M-flex (mean LogMar -0.05) and TECNIS implants (mean LogMar -0.08), which were respectively p < 0.05 and p < 0.01, than ReSTOR implants (mean LogMar 0.02). The UNVA was significantly better after AT.LISAtri (mean LogMar 0.08) and ReSTOR (mean LogMar 0.10) implants than after M-flex (mean LogMar 0.20) and TECNIS (mean LogMar 0.23) implants. Futhermore, the UIVA was statistically significantly better (p < 0.01) in the AT.LISAtri group (mean LogMar 0.07) than in all other groups, as was the ReSTOR group in comparison with the M-flex group and TECNIS group. All groups were spectacle independent for far distance (100 %). The independence on spectacles for near distance was 71.8 % in M-flex, 90.9 % in TECNIS, 100 % in ReSTOR, and 92.9 % in the AT.LISAtri group. 35.1 % of patients reported seeing a constant halo in the M-flex group, along with 25 % of patients in the TECNIS group, 9.1 % of patients in the ReSTOR group, and 28.6 % in the AT.LISAtri group.Conclusion. The four different multifocal IOL designs gave good visual acuity at a distance. UNVA and UIVA was better in apodized diffractive and diffractive trifocal multifocal IOL designs, rather than refractive and bifocal diffractive optical designs. Bilateral visual acuity was higher in all groups than monocular visual acuity. There was no significant difference be-tween halo incidence rates among different multifocal IOLs designs. Glare symptoms during daytime were lower in apodized diffractve and trifocal diffractive multifocal IOL designs.

SANTRAUKAReikšminiai žodžiai: daugiažidininiai intraokuliniai lęšiai, IOL, katarakta, presbiopija, regėjimo aštrumas.Tikslas. Įvertinti regos funkcijos rezultatus po kataraktos pašalinimo operacijų, kurių metu buvo implantuoti keturių skirtin-gų tipų daugiažidininiai intraokuliniai lęšiai.Gydymo įstaiga. Akių ligų klinika, Lietuvos sveikatos mokslų universitetas, Medicinos akademija.Metodai. Atlikus šį prospektyvinį tyrimą, įvertinti regos funkcijos rezultatai šešių mėnesių laikotarpyje po kataraktos ope-

moksliniai tyrimai

49 teorija ir praktika 2014 - T. 20 (Nr. 1)

racijų, kurių metu abipus implantuoti daugiažidininiai intraokuliniai lęšiai: „Rayner M-flex” (M-flex), „TECNIS ZMB00” (TECNIS), „Acrysof ReSTOR” (ReSTOR) ir „AT.LISA tri 839 MP” (AT.LISAtri). Buvo tikrinamas monokulinis ir binoku-linis LogMAR nekoreguotas regėjimo aštrumas į tolį (UDVA), koreguotas regėjimo aštrumas į tolį (CDVA), nekoreguotas regėjimo aštrumas iš arti (UNVA), koreguotas regėjimo aštrumas iš arti (CNVA) ir nekoreguotas regėjimo aštrumas iš vidu-tinio nuotolio (UIVA). Taip pat įvertintas akinių poreikis ir šalutinių optinių fenomenų pasireiškimas.Rezultatai. Iš viso buvo tiriama 170 akių (85 pacientai). Praėjus šešiems mėnesiams po operacijos, statistiškai reikšmingo UDVA ir CNVA skirtumo (p = 0,18) tarp pacientų su skirtingais daugiažidininių intraokulinių lęšių implantais nebuvo. CDVA buvo reikšmingai geresnis su M-flex (LogMAR vidurkis -0,05, p < 0,05) ir TECNIS implantais (LogMAR vidurkis -0,08, p < 0,01) negu su ReSTOR implantais (LogMAR vidurkis 0,02). UNVA buvo reikšmingai geresnis su AT.LISAtri (LogMAR vidurkis 0,08) ir ReSTOR (LogMAR vidurkis 0,10) implantais negu su M-flex (LogMAR vidurkis 0,20) ir TECNIS (LogMAR vidur-kis 0,23) implantais. UIVA buvo statistiškai reikšmingai geresnis (p < 0,01) AT.LISAtri pacientų grupėje (LogMAR vidurkis 0,07) lyginant su kitomis pacientų grupėmis. Pacientų grupėje su ReSTOR implantais UIVA buvo geresnis, nei M-flex ir TECNIS pacientų grupėse. Visų grupių pacientai į tolį akinių nenaudojo (100 proc.). Akiniais iš arti nesinaudojo 71,8 proc. pacientų M-flex grupėje, 90,9 proc. – TECNIS grupėje, 100 proc. – ReSTOR grupėje ir 92,9 proc. – AT.LISAtri grupėje. Aureoles aplink šviesos šaltinį tamsiu paros metu nuolat matė 35,1 proc. pacientų su M-flex implantais, 25 proc. – su TECNIS implantais, 9,1 proc. – su ReSTOR implantais ir 28,6 proc. pacientų su AT.LISAtri implantais.Išvados. Keturi skirtingi daugiažidininiai intraokuliniai lęšiai užtikrino gerą regėjimo aštrumą į tolį. UNVA ir UIVA buvo geresni implantavus apodizuotus difrakcinius ir trijų židinių difrakcinius daugiažidininius intraokulinius lęšius, negu implan-tavus refrakcinius ir dviejų židinių difrakcinius intraokulinius lęšius. Binokulinis regėjimo aštrumas visose grupėse buvo sti-presnis negu monokulinis. Aureoles aplink šviesos šaltinį matančių pacientų skaičius skirtingose pacientų grupėse reikšmingai nesiskyrė. Šviesos sukeliami atspindžiai dienos metu buvo rečiau juntami implantavus apodizuotus difrakcinius ir trijų židinių difrakcinius intraokulinius lęšius.

INTRODUCTIONCataract surgery with an intraocular lens (IOL) implanta-

tion has the potential to improve a patient’s visual acuity and refine the refractive error to a given target. The monofocal IOLs with a single fixated focal length can provide excellent distance vision after cataract surgery [1, 2]. However, most monofocal IOL patients remain dependent on spectacles for satisfactory near vision after surgery. An alternative treatment is the implantation of multifocal IOLs, which give a more ac-ceptable range of near through distance vision as well as in-creased spectacles independence [2, 3, 4]. Studies report that more patients have spectacle freedom after bilateral multifocal IOL implantation than after monofocal IOL implantation [5, 6, 7]. Common problems reported with multifocal IOLs in-clude a loss of contrast sensitivity and increase in photic phe-nomena (glare and halos) [8, 9, 10, 11], with monofocal IOLs having fewer of these problems. There is a variety of multifocal IOLs choices for cataract and refractive surgeon today, all com-panies stand for they product as somehow better than others. Comparing the performance results between different optical designs of multifocal IOLs is hampered for several reasons. There is no standardized follow-up time when evaluating un-wanted visual effects, such as glare and halo (it seems to wane with time [12]). There is no standardized way of distance vis-ual acuity evaluation – some studies present CDVA and some present UDVA. There is no standardized test for near visual acuity – different studies use different charts [13, 14, 15, 16, 17, 18]. These issues make difficult for eye surgeon to compare the results of different multifocal IOLs correctly.

This study assessed the visual functions after the im-plantation of four different multifocal IOLs within the same time frame and using the same examination tools and test.

PATIENTS AND METHODSThe study included cataract extractions with multifocal

IOL implantation performed between December 2009 and May 2013 at the Department of Ophthalmology, Medical Academy, Lithuanian University of Health Sciences, Lithu-ania. All patients provided informed consent after receiving a full explanation of the nature and possible consequences of the surgery. The study was approved by the local ethics committee. Patient exclusion criteria were previous ocular surgeries, preoperative astigmatism more than 1.25 dioptre (D), and ocular diseases other than cataracts.

Intraocular lenses Rayner M-flex 630F (Rayner Intraocular Lenses, Ltd)

(M-Flex). The optic diameter is 6.25 mm, the overall di-ameter 12.5 mm, and haptic angulation 0 degrees. This is a biconvex aspheric refractive multifocal IOL. The IOL has a 360-degree square edge to prevent lens epithelial cell mi-gration and thus posterior capsule opacification. The IOL is made out of hydrophilic acrylic copolymer with an ul-traviolet light filter. The multifocal optical surface on the anterior aspect of the IOL is divided into 5 refractive zones that alternate between 2 powers (base and add power), cre-ating 2 focal points for light entering the eye. The design is distance dominant, thus the greater percentage of light is used more for distance image than near image. This mul-tifocal IOL is pupil dependent. The near addition (add) of the IOL is +3.0 or +4.0 D. It has spherical powers of +14.0 D to +25.0 D in 0.5 D increments.

TECNIS ZMB00 (Abbott Medical Optics, Inc.) (TECNIS) is a hydrophobic acrylic IOL with an optic of 6.00 mm and overall diameter of 13.00 mm. The anterior

moksliniai tyrimai


surface is aspheric, and the posterior surface full diffractive and pupil independent. The light distribution between two focuses is 50-50%. The IOL is made with an ultraviolet light filter. The near addition of the IOL is +4.0 D. The IOL is available in powers ranging from +5.00 D to +32.00 D in 0.5 D increments.

Acrysof ReSTOR (Alcon Labaratories, Inc.) (ReSTOR) is a hydrophobic acrylic IOL with an optic diameter of 6.00 mm and overall diameter of 13.00 mm. This hybrid multifocal IOL combines apodized diffractive and refrac-tive technology. The apodized diffractive optic is on the anterior surface of the IOL and within the central 3.6 mm optic zone of the IOL, which includes 12 concentric steps of gradually decreasing step heights (1.3 to 0.2). The outer part of the optic surrounds the apodized-diffractive region and is the refractive area of the IOL. It directs light to a dis-tance focal point for large pupil diameters and was designed to provide good distance vision. The IOL has an aspheric anterior profile to correct positive spherical aberrations of the cornea. The IOL includes ultraviolet and blue light-fil-tering chromophores. The near addition of the IOL is +3.0 or +4.0 D. The IOL is available in powers ranging from +10.00 D to +34.00 D.

The AT.LISA tri 839 MP (Carl Zeiss Meditec AG) (AT.LISAtri) is a preloaded IOL with a single piece diffractive multifocal design. It has a biconvex optic and overall length of 11.0 mm. It is a foldable hydrophilic acrylate IOL with hydrophobic surface properties. The surface is divided into main zones and phase zones. The diffractive structure has a soft transition of the phase zone between main zones. Dif-fractive rings cover the entire optic diameter. The optic of the IOL consists of a central 4.34 mm trifocal zone and a peripheral bifocal zone from 4.34 to 6.00 mm. This IOL has a trifocal anterior surface and provides an addition of 3.33 D for near and 1.66 D for intermediate at the IOL plane. It is not dependent on pupil diameters up to 4.5 mm. It has a 4-haptic design with an angulation of 0 degree and 360-degree square edge to prevent posterior capsule opacification. It has spherical powers of 0.00 D to +32.0 D in 0.5 D increments.

Preoperative examinationAll patients had a full preoperative ocular examination.

Each examination included the following: UDVA, CDVA, slitlamp biomicroscopy and tonometry. A preoperative dis-tance visual acuity assessment at 4 meters was done with LogMAR units using the 100% contrast Early Treatment Diabetic Retinopathy Study (ETDRS) chart (Optec 6500, StereoOptical Co) under photopic conditions (85 candelas/m²). Biometry was done by partial coherence interferom-etry (IOL Master, Carl Zeiss Meditec). The Holliday 1 and Haigis formulas were used for IOL power calculation, with

target refraction for emmetropia. Patients were assigned in four different groups based on multifocal IOL choice.

All surgeries were performed by one surgeon (V.J.). Phacoemulsification was accomplished with the Infinity Vision System unit (Alcon, Inc.). A main clear corneal inci-sion of 2.2 to 2.4 mm was done on the temporal side. The IOL was implanted in the capsular bag.

Postoperative examinationPostoperative examinations were performed at 1 day, 3

months and 6 months after the surgery. The same investiga-tors (V.J. and P.R.) performed all the assessments.

The primary outcomes measure was monocular and binocular visual acuity, including UDVA and CDVA at 4 m; UIVA at 80 cm; UNVA and CNVA at 40 cm. Postoperative UDVA and CDVA were measured 1 day after the surgery, 3 months after the surgery and 6 months after the surgery; UIVA was assessed at 3 months and 6 months after the sur-gery; UNVA was assessed 1 day after the surgery, 3 months after the surgery and 6 months after the surgery; CNVA was assessed 3 months and 6 months after the surgery. A distance visual acuity evaluation was done with LogMAR units using the 100 % contrast ETDRS chart (Optec 6500, StereoOptical Co) under photopic conditions (85 candelas/m²). Near visual acuity and intermediate visual acuity were measured using the Logarithmic Visual Acuity Chart 2000 New ETDRS (Precision Vision) under photopic conditions (85 candelas/m²). LogMAR is derived from the Logarithm of the Minimum Angle of Resolution. In contrast to other visual acuity charts, such as the Snellen chart, the sizes of the letters progress systematically in geometric progression. The letter size of each line is designated as the logarithm to the base 10 of decimal visual acuity. Each letter has a score value of 0.02 log units. Since there are 5 letters per line, the total score for a line on the LogMAR chart represents a change of 0.1 log units. The formula used in calculating the score is: LogMAR VA = 0.1 + LogMAR value of the best line read - 0.02 × (number of letters read) [38].

Postoperative manifest refraction, keratometry and in-traocular pressure (IOP) were evaluated 3 months and 6 months after surgery. Spectacle independence and photic phenomena were reported 6 months after the surgery. Post-operative autorefraction was followed by manifest refraction and was done by using trial frames. The spherical equiva-lent was taken in to account and evaluated. Corneal astig-matism was measured by partial coherence interferometry (IOL Master, Carl Zeiss Meditec). The patients completed a subjective questionnaire to assess spectacle independence and photic phenomena. Spectacle independence was evalu-ated by asking patient if they use glasses for far and near distances, with the possible three answers being “yes”, “oc-casionally”, or “no”. The glare (explained as increased lu-

moksliniai tyrimai


minance) was assessed by asking patients if they see glare during the day and at night, with the possible three answers being “yes”, “occasionally”, or “no”. The halos (explained as light rings around light source) was assessed by asking if they see halos around lights, with the possible three answers being “yes”, “occasionally”, or “no”.

Statistical analysisThe SPSS statistics software package version 15.0 for

Windows was used for the statistical analysis. Statistical inspection (Kolmogorov-Smirnov testing) of these acuity data as entered in a spreadsheet and partitioned between each multifocal IOL type indicated in each case a Gauss-ian distribution: in the main, parametric procedures (in-cluding t-testing and analysis of variance, ANOVA) were relied upon for the statistical analysis of this material. Gen-eral linear models (GLM) using both the repeated meas-ures ANOVA (three time points) and the two-way mixed design ANOVA (three time points, four groups – M-flex, TECNIS, ReSTOR and AT.LISAtri ) were used to explore the longitudinal effect of VA (followed by Bonferroni post hoc pair-wise comparisons) and the effect of the multifocal IOL type on the VA (F test was reported). The compari-sons in different multifocal IOL types among postoperative periods were made by GLM univariate ANOVA followed by pair-wise comparisons. The F test was used to evaluate the effect of the multifocal IOL. The mean (±SD, standard deviation) is given for each analysed variable. When para-metric analysis was not possible, the Kruskal-Wallis test was used to compare the multifocal IOL groups. For post-hoc analysis, the Mann-Whitney test with the Bonferroni ad-justment was used to avoid an experimental error rate. A p-value of <0.05 was considered significant.

RESULTSThe study involved 170 eyes from 85 patients with a

mean age of 64±9 years (range 39 to 85 years). The M-flex group comprised 46 patients (92 eyes); the TECNIS group 12 patients (24 eyes); the ReSTOR group 12 patients (24 eyes); and the AT.LISAtri group 15 patients (30 eyes). During the study, there were no intraoperative major com-plications (anterior capsular tear or posterior capsular tear, vitreous prolapse, or iris trauma) and no multifocal IOL was explanted. All patients completed all of the follow-up measurements.

PATIENT CHARACTERISTICSTable 1 shows demographics and preoperative patient’s

characteristics. The UDVA of patients was 0.58 (0.00 to 1.60) and the CDVA was 0.45 (0.00 to 1.00); sphere (D) ranged from -18.00 to +6.75, while cylinder (D) ranged from 0 to 2.5; corneal astigmatism (D) ranged from 0.10 to 1.25.

Table 1. Preoperative patient characteristics

Characteristica ValueEyes (n) 170Age (y), mean ± SD 64 ( 9); 39 to 85Sex (F/M) 61/24 UDVA logMAR 0.58 (1.60); 1.60 to 0.00CDVA logMAR 0.45 (0.28); 1.00 to 0.00Keratometry(D) K1 43.52 (1.44); 39.15 to 46.62K2 44.14 (1.45); 39.75 to 47.27MIOL power (D) +20.22 (3.66); +6.0 to +32.0Corneal astigmatism (D) 0.62 (0.28); 0.10 to 1.25 Axial length, mm 23.69 (1.36); 20.77 to 30.58Sphere (D) -0.58 (3.01); -18.00 to +6.75Cylinder (D) -0.25 (0.50); -2.50 to 0.00IOP, mmHg 15.50 (2.43); 10.20 to 24.40

aValue is presented (except eyes and sex) as: mean (SD); range;UDVA, uncorrected distance visual acuity; CDVA, corrected distance visual acuity; MIOL, multifocal intraocular lens; n, number of eyes; K1, flattest meridian; K2, steepest meridian; IOP, intraocular pressure.

Table 2 shows the preoperative characteristics of pa-tients in the four multifocal IOL groups. There were sta-tistically significant differences between groups in sphere, cylinder, IOP and CDVA (all p=0.001), with a trend to-ward better CDVA in the AT.LISAtri group compared to the CDVA in the M-flex group. These differences were the result of the randomization process and do not represent selection bias.

POSTOPERATIVE OUTCOMESThe spherical equivalent was lower in the AT.LISAtri

group than in the M-flex group (p < 0.01) and TEC-NIS group (p < 0.05) at six months postoperatively. The ReSTOR group differs statistically significantly from the M-flex group (0.27±0.45; p < 0.01) (Table 3).

No statistically significant difference was found be-tween the groups in corneal astigmatism at 3 months and 6 months after surgery (Table 3). There were statistically significant differences between groups in IOP at 3 months and 6 months after surgery (both p < 0.001). Six months postoperatively, the ReSTOR group and AT.LISAtri group had significantly lower IOP than the TECNIS group (p < 0.01, Bonferroni test).

VISUAL ACUITY RESULTSVisual acuity results for distance and near vision dur-

ing the postoperative follow-up is presented in Table 4 and visualized in Figure 1 and Figure 2. All four multifocal IOL groups had a significant improvement in UDVA and CDVA after surgery between the 1 day and 3 month fol-low-up (all p < 0.01, repeated ANOVA). Regarding UDVA, CDVA and CNVA, there were no significant differences

moksliniai tyrimai


Table 2. Preoperative patient characteristics according to their multifocal IOL group

M-flex TECNIS ReSTOR AT.LISAtri pb

Characteristica n=92 n=24 n=24 n=301 2 3 4

Age (y) mean (SD) 64 (9) 66 (8) 60 (10) 63 (10) 0.35Range 39 to 85 51 to 76 45 to 77 45 to 81Sex(F/M) (eyes) 64/28 22/2 14/10 22/8 0.07UDVA logMAR 0.59 (0.27) 0.49 (0.33) 0.67 (0.48) 0.55 (0.37) 0.285Range 0.00 to 1.20 0.00 to 1.20 0.00 to 1.60 0.00 to 1.20Sphere (D) 0.16 (2.32)3 -0.87 (1.56) -2.92 (5.16)1,4 -0.39 (2.89)3 0.001Range -6.00 to 6.75 -4.50 to 1.25 -18.00 to 3.00 -6.00 to 5.50Cylinder (D) -0.43 (0.61)2,3,4 0.00 (0.00)1,4 0.0 (0.00)1,4 -0.07 (0.17)1,2,3 <0.001Range -2.50 to 0.00 0.00 to 0.00 0.00 to 0.00 -0.50 to 0.00CDVA logMAR 0.52 (0.25)4 0.42 (0.27) 0.40 (0.32) 0.28 (0.27)1 0.001Range 0.00 to 1.00 0.10 to 0.92 0.00 to 1.00 0.00 to 0.90K1 (D) 43.33 (1.61) 43.94 (1.22) 43.62 (1.29) 43.60 (1.04) 0.37Range 39.15 to 46.62 41.06 to 46.04 40.37 to 45.67 41.51 to 45.36K2 (D) 44.00 (1.61) 44.52 (1.29) 44.23 (1.32) 44.13 (1.06) 0.55Range 39.75 to 47.27 41.41 to 47.01 40.91 to 46.20 42.67 to 45.67Corneal astigmat (D) 0.65 (0.28) 0.57 (0.28) 0.62 (0.30) 0.55 (0.29) 0.28Range 0.11 to 1,25 0.17 to 1.13 0.24 to 1.22 0.10 to 1.16 IOP, mmHg 16.00 (2.19)4 14.75 (1.35) 15.24 (2.84) 14.63 (3.09)1 0.021Range 12.00 to 24.40 12.20 to 17.30 10.20 to 22.40 10.20 to 20.60Axial length, mm 23.69 (1.03) 23.11 (0.87)3 24.25 (2.43)2 23.71 (1.33) 0.018Range 21.42 to 27.16 22.21 to 25.33 20.77 to 30.58 20.95 to 26.07MIOL power (D) 20.16 (2.68) 22.04 (1.96)3 18.84 (6.28)2 20.02 (4.25) 0.024Range 14.0 to 25.00 18.00 to 25.00 6.00 to 29.50 12.00 to 32.00

aValue is presented (except sex) as mean (SD) bOne-way analysis of varianceNumbers in superscript sign MIOL type with significant (p < 0.05) different characteristic (Bonferroni post hoc pair-wise comparisons)Log MAR, Logarithm of the Minimal Angle of Resolution; UDVA, uncorrected distance visual acuity; CDVA, corrected distance visual acuity; MIOL, multifocal intraocular lens; K1, flattest meridian; K2, steepest meridian; IOP, intraocular pressure.

Table 3. Comparison of 3 and 6 months postoperative outcomes between multifocal IOL groups

Characteristica

M-flex n=92

TECNIS n=24

ReSTOR n=24

AT.LISAtri n=30 Pb

1 2 3 4Spherical equivalent (D)3 months 0.25 (0.47)3,4 0.23 (0.53)4 0.08 (0.22)1 -0.03 (0.08)1,2 <0.001Range -0.87 to 1.62 -0,5 to 1.50 -1.00 to 0.00 -0.25 to 0.006 months 0.27 (0.45)3,4 0.21 (0.55) -0.06 (0.19)1 -0.03 (0.08)1 <0,001Range -0.75 to 1.25 -0.75 to 1.25 - 1.0 to 0.00 -0.25 to 0.00Corneal astigmatism (D)3 months 0.57 (0.30) 0.50 (0.22) 0.52 (0.24) 0.45 (0.20) 0.185Range 0.00 to 1.19 0.16 to 1.07 0.00 to 1.00 0.00 to 1.006 months 0.57 (0.30) 0.50 (0.22) 0.53 (0.23) 0.45 (0.20) 0.167Range 0.00 to 1.17 0.16 to 1.07 0.00 to 1.00 0.00 to 1.00IOP (mm Hg)3 months 15.39 (2.28)3 16.42 (1.54)3,4 14.15 (1.81)1,2 13.93 (1.84)2 <0.001 Range 7.10 to 20.60 14.60 to 20.60 12.20 to 17.30 10.20 to 17.306 months 15.44 (2.25) 16.27 (1.90)3,4 14.25 (1.77)2 14.43 (1.93)2 <0.001Range 7.10 to 20.60 12.20 to 20.60 12.20 to 17.30 12.20 to 17.30

aValue is presented as mean (SD)bOne-way analysis of varianceNumbers in superscript sign MIOL type with significant (p < 0.01) different characteristic (Bonferroni post hoc comparisons); IOP, intraocular pressure.

moksliniai tyrimai


between groups after surgery 3 months later (p > 0.13) (Ta-ble 4). The CDVA 6 months after surgery was better in the TECNIS and M-flex groups than the ReSTOR group. The UNVA at 3 months was statistically significantly (p < 0.01) better in the ReSTOR and AT.LISAtri groups than in both M-flex and TECNIS groups (Table 4, Figure 2).

In all multifocal IOL groups, the visual outcomes did not change significantly between 3 months and 6 months post-operatively (p > 0.15, repeated ANOVA) (Figure 1, Figure 2).

Regarding UIVA (Figure 3), the groups did not change in UIVA over time between the 3-month and 6-month follow-up. The UIVA was statistically significantly (p < 0.01) better in the AT.LISAtri group than in all of the other groups.

Table 4. Comparison of the follow-up postoperative visual acuity between the multifocal IOL groups

Visual acuitya

M-flex n=92

TECNIS n=24

ReSTOR n=24

AT.LISAtri n=30 Pb

1 2 3 4UDVA1 day 0.14 (0.14)4 0.17 (0.14) 0.20 (0.17) 0.24 (0.21)1 0.022

-0.10 to 0.70 -0.02 to 0.50 -0.08 to 0.70 0.00 to 0.803 months 0.00 (0.10) 0.01 (0.14) 0.01 (0.09) -0.02 (0.08) 0.525

-0.22 to 0.30 -0.20 to 0.30 -0.18 to 0.20 -0.20 to 0.806 months 0.01 (0.11) 0.01 (0.13) 0.04 (0.11) -0.03 (0.08) 0.177

-0.20 to 0.30 -0.20 to 0.30 -0.12 to 0.40 -0.20 to 0.14CDVA1day 0.10 (0.12)4 0.16 (0.15) 0.18 (0.17) 0.21 (0.21)1 0.006

-0.14 to 0.60 -0.02 to 0.50 -0.08 to 0.70 -0.20 to 0.803 months -0.08 (0.27) -0.09 (0.14) -0.01 (0.08) -0.04 (0.09) 0.352

-1.80 to 0.14 -0.50 to 0.20 -0.18 to 0.20 -0.20 to 0.126 months -0.05 (0.09)3 -0.08 (0.13)3 0.02 (0.10)1,2 -0.05 (0.10) 0.006

-0.20 to 0.14 -0.50 to 0.20 -0.20 to 0.14 -0.20 to 0.14UNVA1day 0.37 (0.13) 0.36 (0.12) 0.37 (0.16) 0.44 (0.18) 0.093

-0.10 to 0.64 0.10 to 0.50 0.10 to 0.90 0.20 to 0.903 months 0.19 (0.14)3,4 0.21 (0.17)3,4 0.09 (0.07)1,2 0.08 (0.09)1,2 <0.001

-0.18 to 0.60 -0.18 to 0.50 -0.06 to 0.24 -0.12 to 0.246 months 0.20 (0.15)3,4 0.23 (0.16)3,4 0.10 (0.13)1,2 0.08 (0.09)1,2 <0.001

-0.18 to 0.60 -0.18 to 0.50 -0.06 to 0.60 -0.12 to 0.26CNVA3 months 0.104 (0.12) 0.117 (0.15) 0.065 (0.06) 0.057 (0.11) 0.133

-0.20 to 0.40 -0.18 to 0.40 -0.06 to 0.20 -0.20 to 0.246 months 0.116 (0.12) 0.092 (0.13) 0.080 (0.12) 0.072 (0.11) 0.300

-0.20 to 0.40 -0.18 to 0.38 -0.06 to 0.20 -0.10 to 0.26UIVA3 months 0.25 (0.09)2,3,4 0.46 (0.09)1,3,4 0.16 (0.16)1,2,4 0.07 (0.11)1,2,3 <0.001

0.00 to 0.46 0.34 to 0.64 -0.12 to 0.46 -0.10 to 0.286 months 0.26 (0.09)2,3,4 0.46 (0.09)1,3,4 0.17 (0.17)1,2,4 0.07 (0.10)1,2,3 <0.001

0.00 to 0.44 0.34 to 0.64 -0.12 to 0.46 -0.10 to 0.30

aValue is presented as mean (SD) and srangebOne-way analysis of varianceNumbers in superscript sign MIOL type with significant (p < 0.01) different characteristic (Bonferroni post hoc comparisons)

BILATERAL VISUAL ACUITY RESULTSTable 5 presents the bilateral visual acuity at the

3-month and 6-month follow-ups. There were no sta-tistically significant differences between 3 and 6 postop-erative months in the bilateral visual acuity in all groups. Three months postoperatively, the AT.LISAtri group and ReSTOR group had statistically significantly better bilater-al UNVA and UIVA than the M-flex and TECNIS groups (p < 0.01, Bonferroni test).

SUBJECTIVE ASSESSMENTOverall, patients with multifocal IOL didn’t show a

spectacle need for far distance. All patients in all groups

moksliniai tyrimai


UDVAFollow-up trend was different between IOL [F(3;166) = 5.8; p = 0.001]1 day: M-flex vs. AT.LISAtri, p = 0.0213 months: differences between groups not found6 months: differences between groups not found

CDVAFollow-up trend was different between IOL [F(3;166) = 4.36; p = 0.005]1 day: F(3;166)=4.3; p = 0.006M-flex vs AT.LISAtri p = 0.010 3 months: differences between groups not found6 months: F(3;166) = 4.3; p = 0.006;ReSTOR vs M-flex p = 0.019;and vs TECNIS, p = 0.005

Figure 1. The postoperative visual acuity (UDVA, CDVA) at follow-up, 1 day, 3 and 6 months

UNVAFollow-up trend was different between MIOL [F(3;166) = 10; p < 0.001]1 day: the differences between MIOL not found 3 months: F(3;166) = 9.5; p < 0.001;M-flex vs. ReSTOR, p = 0.003; and vs. AT.LISAtri, p < 0.001TECNIS vs. ReSTOR, p = 0.011; and vs. AT.LISAtri, p = 0.0026 months: F(3;166) = 8.4; p < 0.001;M-flex vs ReSTOR, p = 0.020; and vs AT.LISAtri, p = 0.001TECNIS vs ReSTOR, p = 0.013; and vs AT.LISAtri, p = 0.001

CNVAFollow-up trend was the same between MIOL F(3;166) = 2.34; P = 0.0753 months: F(3;166) = 1,9; p = 0.13;the differences between MIOL not found 6 months: F(3;166) = 8.3; p = 0.3;the differences between MIOL no found

Figure 2. The postoperative visual acuity (UNVA, CNVA) at follow-up, 1 day, 3 and 6 months

moksliniai tyrimai


Table 5. Bilateral visual acuity of patients during follow–up according to IOL type

Visual acuitya

M-flex n=46

TECNIS n=12

ReSTOR n=12

AT.LISAtri n=15 pb

1 2 3 4Bilateral UDVA3 months -0.05 (0.10) -0.05 (0.14) -0.01 (0.08) -0.06 (0.09) 0.771

-0.30 to 0.08 -0.22 to 0.40 -0.20 to 0.08 -0.20 to 0.086 months -0.04 (0.14) -0.03 (0.14) -0.01 (0.07) -0.67 (0.09) 0.433

-0.30 to 0.60 -0.22 to 0.28 -0.14 to 0.10 -0.20 to 0.08Bilateral CDVA3 months -0.09 (0.09) -0.07 (0.16) -0.04 (0.07) -0.08 (0.10) 0.263

-0.30 to 0.08 -0.22 to 0.40 -0.20 to 0.02 -0.20 to 0.086 months -0.10 (0.09) -0.07 (0.16) -0.02 (0.06) -0.09 (0.09) 0.018

-0.30 to 0.08 -0.22 to 0.40 -0.14 to 0.10 -0.20 to 0.08Bilateral UNVA3 months 0.15 (0.15)3,4 0.13 (0.15)4 0.04 (0.07)1 0.02 (0.08)1,2 <0.001

-0.18 to 0.60 -0.04 to 0.42 -0.08 to 0.20 -0.12 to 0.186 months 0.14 (0.14)3 0.13 (0.15)3 0.05 (0.07)1,2 0.02 (0.09) <0.001

-0.18 to 0.60 -0.04 to 0.42 -0.08 to 0.20 -0.12 to 0.24Bilateral CNVA3 months 0.06 (0.12)4 0.08 (0.13) 0.03 (0.07) 0.00 (0.11)1 0.042c

-0.28 to 0.30 -0.04 to 0.40 -0.08 to 0.20 -0.20 to 0.186 months 0.08 (0.12)4 0.04 (0.09) 0.04 (0.07) 0.00 (0.11)1 0.012

-0.28 to 0.30 -0.08 to 0.20 -0.08 to 0.20 -0.20 to 0.24Bilateral UIVA3 months 0.21 (0.10)2,3,4 0.41 (0.09)1,3,4 0.11 (0.15)1,2 0.04 (0.09)1,2 <0.001

-0.04 to 0.38 0.32 to 0.60 -0.10 to 0.42 -0.10 to 0.246 months 0.22 (0.09)2,3,4 0.40 (0.09)1,3,4 0.11 (0.15)1,2 0.04 (0.10)1,2 <0.001

0.00 to 0.38 0.32 to 0.60 -0.10 to 0.42 -0.10 to 0.28

aValue is presented as mean (SD) and rangebFor difference between IOL groupscMann-Whithney testNumbers in superscript sign IOL type with significant (p < 0.01) different characteristic (Bonferroni post hoc comparisons)

Figure 3. Changes in LogMAR UIVA levels by postoperative period in eyes according to different type of multifocal IOL

Figure 4. Spectacle dependence for near distance 6 months after surgery

denied that they need glasses for distance 6 months after surgery (100% answered “no”).

Figure 4 summarizes the need for reading glasses 6 months after surgery. Patients in the ReSTOR and AT.LISAtri groups needed reading spectacles less often than patients in the M-flex and TECNIS groups (c2 = 8.8 df = 3 p = 0.054). Patients in the ReSTOR group didn’t need reading glasses at all.

In all four groups, patients noticed glare during day and night time. The incidence of glare 6 months after sur-gery is presented in Figure 5 and Figure 6. Glare incidence rates at day time were significantly lower in the ReSTOR and AT.LISAtri groups (c2 = 13.2 df = 3 p = 0.040). Glare incidence rates at night time didn’t show any significant dif-ference between groups (c2 = 11.4 df = 3 p = 0.077).

moksliniai tyrimai


Figure 7 presents the information concerning the inci-dence rates of the halo seen around lights. All groups no-ticed halos around light sources at night, but no significant differences were found between the groups (c2 = 7.1 df = 3 p = 0.31).

DISCUSSIONMultifocal IOLs have been providing visual rehabilita-

tion for distance and near visual acuity for more than 30 years [19]. Multifocal IOLs were designed to improve vision at different distances by increasing the depth of perception in the eye [20]. The main goal of implanting this type of IOLs is to provide the best levels of spectacle independence [21]. The most frequently used designs of multifocal IOLs up to now have been refractive, diffractive or a combination of both (hybrid refractive-diffractive). In this clinical trial, we evaluated the visual function of four different designs of multifocal IOLs. Most multifocal IOL trials focus on one multifocal IOL design or a comparison of two multifocal IOL designs when assessing visual function.

There is a problem that arises when trying to compare results from different study settings and tools. There should be a more standardized evaluation of patients’ data and fol-low-up periods in order to better compare studies.

In this study, there was notable improvement in UDVA and CDVA after cataract removal and multifocal IOL implan-tation in all four groups. No statistical significant difference in UDVA was found between the four groups. We found that at six months after surgery, CDVA was better in the TECNIS and M-flex groups than in the ReSTOR group. We were not able to find an explanation in the available literature as to why CDVA in the TECNIS group and M-flex group was found to be better than in the ReSTOR group. Other studies of refrac-tive, diffractive or hybrid multifocal IOLs after six months also showed good UDVA and CDVA results [6, 22, 23] and these results compare favourably with ours.

The UNVA and CNVA were good and were able to pro-vide near visual acuity. Other studies also report good post-operative UNVA with multifocal IOLs [6, 22, 25]. There was a statistical difference in UNVA found between groups with the best results in both the ReSTOR and AT.LISAtri groups, followed by the M-flex and TECNIS groups. This could be explained by a lower spherical equivalent in the AT.LISAtri and ReSTOR groups and supports the opinion that even a small residual ametropia plays an important role on UNVA with multifocal IOLs [24]. However, there was no exact correlation with better UNVA and lower spherical equivalent between the M-flex and TECNIS groups, and this leaves some questions for further research. There was no significant difference in CNVA between the groups.

The UIVA was statistically significantly better in the AT.LISAtri group than in all other groups at 3 months and 6 months. In the ReSTOR group, UIVA was statistically significantly better than in both the M-flex group and the TECNIS group. This finding supports data from other studies that trifocal optics and apodized refractive-difractive optics provide better intermediate visual acuity [26, 27, 37].

Overall, visual acuity increased dramatically after 3 months compared with the first day follow-up in all four groups. This could be explained by the demand for a cer-tain period of time for ocular structures to be restored af-ter the cataract surgery, as the first post-op day is related Figure 5. Glare during the daytime 6 months after surgery

based on the questionnaire

Figure 6. Glare during the night 6 months after the surgery based on the questionnaire

Figure 7. Halos reported 6 months after the surgery based on the questionnaire

moksliniai tyrimai


with a higher incidence of corneal haze and increased IOP [36, 37]. There was no significant difference in visual acuity concerning 3-month and 6-month follow-ups in between the same group, and this shows stability in visual acuity 3 months after the surgery.

The improvement of distance and near visual acuity after the implantation of multifocal IOL in this study is strongly supported by twenty-nine other studies where im-provement in UDVA and UNVA visual acuities were re-ported. These results show the aggregate of studies report-ing a beneficial increase in UDVA and UNVA after using multifocal IOLs in cataract patients [28].

Bilateral visual acuity was better than unilateral visual acuity in all groups. This is the same as found in other stud-ies [29].

None of patients used any kind of distance glasses at all, and this provides us with information that the distance vi-sion is appropriate, as was found in other studies as well [28].

In this study, the ReSTOR and AT.LISAtri IOLs pro-vided better UNVA than M-flex and TECNIS multifocal IOLs, leading to less of a need for near spectacles. The re-fractive multifocal IOL design leads to a greater need for near spectacles. There are some studies supporting this proposition [30].

Corneal astigmatism of 1.25 D or more is prevalent in approximately 30% of eyes that have cataract surgery [31]. Studies have shown that postoperative astigmatism of 1.50 D or more leads to poor optical quality, compromised distance and intermediate visual acuity, and a greater halo effect in eyes with multifocal IOLs [24]. The inclusion cri-teria in this study were not to exceed a corneal astigmatism of 1.25 D, and we were attempting not to induce corneal astigmatism by making temporal corneal incision. The main incision sizes were between 2.2 and 2.4 mm. Studies on the corneal incisions in phacoemulsification have led to a conclusion that a superior location induces greater ker-atometric changes than a temporal incision and this effect could be intentionally used by the surgeon to avoid induc-ing or even reducing preexisting astigmatism [32]. Some studies report that a small, clear corneal incision of up to 2.75 mm induced little refractive change in eyes with low preoperative corneal astigmatism, regardless of where the incision site is [33]. This is why we don’t see significant keratometric changes after surgery in this study.

Some of patients answered “yes” when asked about ha-los, and some of them noticed moderate to severe glare. In terms of halo, the rates between different designs of mul-tifocal IOLs did not differ significantly. We found that tri-focal diffractive and hybrid apodized diffractive-refractive multifocal IOLs were less related with glare symptoms during daytime (we have not found data on this in the lit-erature to date). We did not find a significant relationship

between glare severity and visual acuity, but there was a tendency toward lower visual acuity and higher glare sever-ity during the day in M-flex and TECNIS groups, keeping in mind that visual acuity was tested under photopic con-ditions. Photic phenomena, such as halos and glare, have been reported by patients in previous studies of multifocal IOLs [6, 34, 35]. Results vary between publications, and this might be due to different severity grading scales, as well as different questions and answers on the questionnaires.

CONCLUSIONIn this study, we found that the four different multifo-

cal IOL designs provided very good visual acuity at a dis-tance. UNVA and UIVA were better in hybrid apodized refractive-diffractive and trifocal diffractive multifocal IOL designs than refractive and bifocal diffractive multifocal IOLs. The binocular visual acuity with all multifocal IOL designs was better then monocular visual acuity. There was no difference between halo incidence among the different multifocal IOL designs. Less glare was reported during the daytime with hybrid apodized refractive-diffractive and tri-focal diffractive multifocal IOL designs.

REFERENCES1. Becker KA, Martin M, Rabsilber TM, Entz BB, Reuland AJ,

Auffarth GU. Prospective, non-randomised, long term clinical evaluation of the foldable hydrophilic single piece intraocular lens: results of Centerflex FDA study. Br J Ophthalmol 2006; 90:971-974.

2. Vilaseca M, Arjona M, Pujol J, Issolio L, Guell JL. Optical qu-ality of foldable monofocal intraocular lenses before and after injection: comparative evaluation using a double –pass system. J Cataract Refract Surg 2009; 35:1415-1423.

3. Lane SS, Morris M, Nordan L, Packer M, Tarantino N, Wallace RB III. Multifocal intraocular lenses. Ophthalmol Clin North Am 2006; 19(1):89-105.

4. Bellucci R. Multifocal intraocular lenses. Curr Opin Ophthal-mol 2005; 16:33-37.

5. Lindstrom RL. Food and Drug Administration study update; one year results from 671 patients with the 3M multifocal intra-ocular lens. Ophthalmology 1993; 100:91-97.

6. Kohnen T, Allen D, Boureau C, Dublineau P, Hartmann C, Mehdorn E, Rozot P, Tassinari G. European multicenter study of the AcrySof ReSTOR apodized diffractive intraocular lens. Ophthalmology 2006; 113:578-584.

7. Alfonso JF, Puchades C, Fernandez-Vega L, Montes-Mico R, Valcarcel B, Ferrer-Blasco T. Visual acuity comparison of 2 models of bifocal aspheric intraocular lenses. J Cataract Refract Surg 2009; 35:672-676.

8. Montes – Mico R, Espana E, Bueno I, Charman WN, Menezo JL. Visual performance with multifocal intraocular lenses; me-sopic contrast sensitivity under distance and near conditions. Ophthalmology 2004; 111:85-96.

9. Leyland M, Zinicola E. Multifocal versus monofocal intraocular lenses in cataract surgery; a systematic review. Ophthalmology 2003; 110:1789-1798.

10. Woodward MA, Randleman JB, Stulting RD. Dissatisfaction after multifocal intraocular lens implantation. J Cataract Refract Surg 2009; 35:992-997.

11. Hofman T, Zuberbuhler B, Cervino A, Montes-Mico R, Haef-liger E. Retinal straylight and complaint scores 18 months after

moksliniai tyrimai


implantation of the AcrySof monofocal and ReSTOR diffracti-ve intraocular lenses. J Refract Surg 2009; 25:485-492.

12. Webers CAB, Montes-Mico R, Tahzib NG, Cheng YYY, de Bra-bander J, Hendrikse F, Nuijts RMMA. Long–term follow-up of a multifocal apodized diffractive intraocular lens after cataract surgery. J Cataract Refract Surg 2008; 34:1476-1482.

13. Cillino S, Casuccio A, Di Pace F, Morreale R, Pillitteri F, Cillio G, Lodato G. One-year outcomes with new-generation multifo-cal intraocular lenses. Ophthalmology 2008; 115:1508-1516.

14. Mester U, Junker B, Kaymak H. Functional results with two multifocal intraocular lenses with different near addition. Opht-halmologe 2011; 108:137-142.

15. Brown D, Dougherty P, Gills JP, Hunkeler J, Sanders DR, San-ders ML. Functional reading acuity and performance: Compa-rison of 2 accommodating intraocular lenses. J Cataract Refract Surg 2009; 35:1711-1714.

16. Hutz WW, Eckhardt HB, Rohring B, Grolmus R. Reading abi-lity with 3 multifocal intraocular lens models. J Cataract Refract Surg 2006; 32:2015-2021.

17. Ito M, Shimizu K. Reading ability with pseudophakic monovi-sion and with refractive multifocal intraocular lenses: compara-tive study. J Cataract Refract Surg 2009; 35:1501-1504.

18. De Vries NE, Nuijts RMMA. Multifocal intraocular lenses in cataract surgery: Literature review of benefits and side effects. J Cataract Refract Surg 2013; 39:268-278.

19. Agresta B, Knorz MC, Kohnen T, Donatti C, Jackson D. Dis-tance and near visual acuity improvement after implantation of multifocal intraocular lenses in cataract patients with presbyo-pia: a systematic review. J Refract Surg 2012; 28:426-435.

20. Belluci R. Multifocal intraocular lenses. Curr Opin Ophthalmol 2005; 16:33-37.

21. Toto L, Falconio G, Vecchiarino L, Scorcia V, Di Nicola M, Ballone E, Mastropasqua L. Visual performance and biocompa-tibility of 2 multifocal diffractive IOLs; six-month comparative study. J Cataract Refract Surg 2007; 33:1419-1425.

22. Vingolo EM, Granga P, Iacobelli L, Grenga R. Visual acuity and contrast sensitivity; AcrySof ReSTOR apodized diffractive ver-sus AcrySof SA60AT monofocal intraocular lenses. J Cataract Refract Surg 2007; 33:1244-1247.

23. Zelichowska B, Rekas M, Stankiewicz A, Cervino A, Montes-Mico R. Apodized diffractive versus refractive multifocal intra-ocular lenses: optical and visual evaluation. J Cataract Refract Surg 2008; 34:2036-2042.

24. Hayashi K, Manabe S-i, Yoshida M, Hayashi H. Effect of as-tigmatism on visual acuity in eyes with diffractive multifocal intraocular lens. J Cataract Refract Surg 2010; 36:1323-1329.

25. Chiam PJT, Chan JH, Haider SI, Karia N, Kasaby H, Aggarwal RK. Functional vision with bilateral ReZoom and ReSTOR in-traocular lenses 6 months after cataract surgery. J Cataract Ref-ract Surg 2007; 33:2057-2061.

26. Mojzis P, Pena-Garcia P, Liehneova I, Ziak P, Alio JL. Outcomes of a new diffractive trifocal intraocular lens. J Cataract Refract Surg 2014; 40:60-69.

27. Sheppard AL, Shah S, Bhatt U, Bhogal G, Wolffsohn JS. Visual outcomes and subjective experience after bilateral implantation of a new diffractive trifocal intraocular lens. J Cataract Refract Surg 2013; 39:343-349.

28. Argesta B, Knorz MC, Kohnen T, Donatti C, Jakson D. Dis-tance and near visual acuity improvement after implantation of multifocal intraocular lenses in cataract patients with presbyo-pia: a systematic review. J Refract Surg 2012; 28:426-435).

29. Jaccobi FK, Kammann J, Jacobi KW, Grobkopf U, Walden K. Bilateral implantation of asymmetrical diffractive multifocal in-traocular lenses. Arch Ophthalmol 1999; 117:17-23.

30. Alio JL, Grabner G, Plaza-Puche A, Rasp M, Pinero DP, Sey-eddain O, Rodriguez-Prats J, Ayala MJ, Moreu R, Hohensinn M, Riha W, Dexl A. Postoperative bilateral raeding performance with 4 intraocular lens models: Six-months results. J Cataract Refract Surg 2011; 37:842-852.

31. Hoffmann PC, Hutz WW. Analysis of biometry and prevalence data for corneal astigmatism in 23,239 eyes. J Catarct Refract Surg 2010; 36:1479-1485.

32. Tejedor J, Murube J. Choosing the location of corneal incision based on preexisting astigmatism in phacoemulsification. Am J Ophthalmol. 2005; 139:767-776.

33. Giasanti F, Rapizzi E, Virgili G, Mencucci R, Bini A, Vannozzi L, Menchini U. Clear corneal incision of 2.75 mm for cataract surgery indices little change of astigmatism in eyes with low pre-operative corneal cylinder. Eur J Ophthalmol. 2006; 16:385-393.

34. Kohnen T, Nuijits R, Levy P, Haefliger E, Alfonso JF. Visual function after bilateral implantation of apodized diffractive as-pheric multifocal intraocular lenses with a +3,0 D addition. J Cataract Refract Surg 2009; 35:2062-2069.

35. Lichtinger A, Rootman DS. Intraocular lenses for presbyopia correction: past, present, and future. Curr Opin Ophthalmol 2012; 23:40-46.

36. Arshinoff SA, Albiani DA, Taylor-Laporte J. Intraocular pressu-re after bilateral cataract surgery using Healon, Healon5, and Healon GV. J Cataract Refract Surg 2002; 28:617-625.

37. Moser CL, Martin-Baranera M, Garat M, de Miguel PV, Rubio M. Corneal edema and intraocular pressure after cataract sur-gery: Randomized comparison of Healon5 and Amvisc Plus. J Cataract Refract Surg 2004; 30:2359-2365.

38. Holladay JT. Proper method for calculating average visual acui-ty. J Refract Surg 1997; 13(4):388-91.

Gautas 2013 m. spalio 10 d., aprobuotas 2014 m. sausio 3 d.Submitted October 10, 2013, accepted January 3, 2014

results on the comparison of visual … 360-degree square edge to prevent lens epithelial cell...

Documents