Visual performance after implantation of corrective intraocular lenses for presbyopia


study design

This was a prospective randomized clinical trial conducted at the Department of Ophthalmology, Dar Alshifa Hospital, Kuwait between June 2019 and May 2020. The study was approved by the ethics committee of the hospital Dar Alshifa. All patients signed a written consent after explanation of the surgical procedure and vision problems of IOLs correcting presbyopia. The study followed the principles of the Declaration of Helsinki and adhered to the CONSORT guidelines for reporting clinical trials: and was registered on ID: NCT04907955. Unique Protocol ID: 02282021065727,

Inclusion/exclusion criteria

Patients diagnosed with bilateral senile cataract, motivated for spectacle independence but with imprecise vision tolerance, with scotopic pupil size

Exclusion criteria included pseudoexfoliation, traumatic cataract, history of eye surgery, glaucoma, low endothelial cell count 2high myopia (axial length > 25.5 mm) and hypermetropia (axial length 70 years old) due to probable difficult neuroadaptation to new optical conditions, history of stroke or dyslexia, unrealistic visual expectations, patients requiring precise vision, e.g. pilots, drivers, etc., patients satisfied with reading glasses, patients dissatisfied with progressive lenses.

Randomization and masking

Patients were randomly selected (https:// distributed for the bilateral implantation of one of the three non-toric IOLs correcting presbyopia; Acrysof IQ PanOptix TNFT00 (Alcon Laboratories, Inc., Forth Worth, USA) (Group A), AT LISA tri 839MP (Calr Zeiss MEditech, Germany) (Group B) and TECNIS Symfony ZXR00 (J&J Vision , Inc. , Santa Ana, USA) (Group C). The study was double-blind. The patients were masked with respect to the type of IOL implanted. All preoperative and postoperative evaluations were done by the same author, who was masked to the type of IOL implanted.

Intraocular lens criteria

Acrysof PanOptix

It is a one-piece aspherical IOL (negative asphericity of -0.10 μm), with a non-apodized diffractive design. It has a central part of 4.5 mm with 15 diffractive zones. It divides the light into three focal points, distant, intermediate (60 cm) and near (40 cm). The lens has an overall diameter of 13.0mm and an optical diameter of 6.0mm and is available in powers from +13.0D to +34.0D [3, 13].

AT LISA tri 839MP

It is a preloaded one-piece hydrophilic acrylic IOL with a hydrophobic surface and UV absorber. It has an aspherical diffractive design that compensates for corneal spherical aberrations. It has a central trifocal zone of 4.34 mm and a peripheral bifocal zone of 4.34–6.00 mm. The light is distributed asymmetrically between three focal points; distant (50%), intermediate (20%) and close (30%). The IOL has a near addition (addition) of +3.33 D and an intermediate addition of +1.66 D at 80 cm. Overall length is 11.0mm with an optical diameter of 6.0mm with diopter power from 0.0 to +32.0D in 0.5D increments [14].

TECNIS Symfony ZXR00

It is a hydrophobic acrylic biconvex aspheric IOL. It has a wavefront designed anterior aspherical surface (-0.27 µm negative spherical aberration) which compensates for corneal sharp positive spherical aberrations thus improving contrast sensitivity. The echelon design of the achromatic diffractive rear surface lengthens the depth of field and increases the viewing range rather than splitting the light into foci. This eliminates the halo effect generated by the overlapping of near and far images, formed by multifocal IOLs. The IOL has an overall diameter of 13.0 mm with an optical diameter of 6.0 mm. It has an intermediate added power of +1.75 D and available powers range from +5.0 to +34.0 D in 0.5 D increments [11, 15].

Preoperative evaluation

All patients had a complete ophthalmological examination. This included measurement of distance-corrected visual acuity (CDVA) using Early Treatment Diabetic Retinopathy Study (ETDRS) charts (ETDRS Standardized Viewer Model No. ESV 3000) at 4 m with 100% contrast in photopic conditions (85 candelas/m2), then the results were converted to logarithm of minimum angle of resolution (logMAR) for analysis. Manifest refraction was performed using the Topcon C5000 Digital Eye Examination System (Topcon, Canada) to provide Sphere, Cylinder, and Manifest Refractive Spherical Equivalent (MRSE). The examination also included slit lamp evaluation, Goldmann applanation tonometry, fundoscopy, keratometry, corneal tomography (Sirius, CSO, Italy) and optical biometrics (IOLMaster 500, Carl Zeiss Meditec AG) . Intraocular In the bag, IOL power calculation was performed using the SRK/T formula (for AL > 22.0 mm) or the Hoffer Q formulas (for AL

Surgical technique and postoperative care

All surgeries were performed by an experienced surgeon (YAA). All eyes underwent a standard 2.2 mm clear corneal incision phacoemulsification procedure with IOL implantation in the sac. The postoperative regimen included moxifloxacin 0.5%, prednisolone acetate ophthalmic suspension 1%, and nepafenac ophthalmic suspension 0.1%, every 4 hours for 2 weeks, then tapered over Three weeks. In all patients, the other eye was operated on 2 weeks after the first eye with implantation of the same IOL in both eyes.

Postoperative evaluation

All patients were examined on the first day, the first week, the first and the sixth postoperative month.

Visual acuity

The following visual acuities were assessed; monocular uncorrected distance visual acuity (UDVA) at 4 m, corrected distance visual acuity (CDVA) (4 m), uncorrected intermediate visual acuity at 60 cm (UIVA 60 cm) and at 80 cm (UIVA 80 cm), uncorrected near visual acuity (40 cm) (UNVA) and distance-corrected near visual acuity (DCNVA).

Distance-corrected binocular defocus curve

For the evaluation of the field of functional vision, binocular defocus curve obtained 6 months after the operation under photopic conditions (85 candelas/m2), with scope distance correction, using ETDRS cards at a distance of 4 m. Defocus lenses from +1.00 D to -4.00 D were introduced in 0.50 D steps.

Contrast sensitivity

Binocular contrast sensitivity at 4 meters was measured 6 months postoperatively with corrective glasses worn as needed. The CSV-1000 system (Vector Vision Inc. Greenville, USA) was used, under photopic and mesopic conditions without glare, with spatial frequencies of 3 to 18 cycles/degree.

Photic phenomena and independence of the spectacle

Patients were asked to answer a questionnaire on the frequency, severity and degree of discomfort of halos, glare and starburst and another Yes/No questionnaire on the independence of spectacles for distance, intermediate and distance vision. close. 16

Outcome measures

Main outcomes included Monocular AVUI at 80 and 60 cm and monocular UNVA and DCNVA at 40 cm, 6 months after second eye surgery.

Secondary outcome measures included Monocular UDVA and CDVA at 4 m, SE refraction, binocular distance corrected defocus curve, contrast sensitivity, photic phenomena and wearing glasses 6 months after second eye surgery.

Determination of sample size

For the sample size calculation, G*power software was used, based on the mean monocular VAUI at 80 cm, considering 0.36 LogMAR as a clinically significant difference with 0. 13 as standard deviation [16]. Therefore, for an alpha value of 0.05 and a power of 0.95, the calculated minimum sample size was 105 eyes. A 20% of this number was added to compensate for the tracking loss (21 eyes), hence the final sample size was 126 eyes (42 eyes per group).

statistical analyzes

Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 25 (version 22.0, IBM Corp.). The normality of the data was verified by the Kolmogorov-Smirnov test. Numbers and percentages were used to express qualitative data while means (±SD) or medians (first and third quartiles: Q1, Q3) were used to express quantitative data. Between-group comparisons were made using the one-way ANOVA test for normally distributed data and the chi-square test for binomial and ordinal data. Visual results were compared between IOL groups using the Kruskal-Wallis test, with Bonferroni’s adjustment for post hoc analysis. P a value ≤ 0.05 was considered statistically significant.


Comments are closed.