Purpose
To evaluate and compare the objective refractions obtained by autorefraction and aberrometry under different lighting conditions with an isofocal intraocular lens (Isopure, BVI medical, ...Liége, Belgium) compared to a monofocal control lens (Micropure, BVI medical, Liége, Belgium) with the same platform and material.
Methods
Prospective, comparative and randomized study on patients undergoing cataract surgery and bilateral isofocal or monofocal IOL implantation. A total of 44 subjects were randomly assigned to either the isofocal group (
n
= 22) or the Micropure (
n
= 22). Manifest refraction (MR) was always performed under the same lighting conditions for all the patients. For objective refraction the autorefractor KR8800 and the aberrometer OPD-Scan III (Nidek Inc., Tokyo, Japan.) were used. For each eye included in the study, six result sets were collected: MR, AR (autorefraction measured with the autorefractor), WF-P and WF-M (Zernike-coefficients-based objective refraction, photopic and mesopic pupil size), OPD-C and OPD-M (autorefraction measured with the aberrometer in photopic and mesopic conditions).
Results
The mean sphere for MR was 0.03 ± 0.32D for the Isopure group and 0.24 ± 0.22D for the monofocal group (
p
= 0.013). For the Isopure group, Friedman analysis showed statistically significant differences for sphere measured with WF-P (
p
= 0.035), WF-M (
p
= 0.018) and OPD-M (
p
= 0.000), and SE measured with OPD-M (p = 0.004). In the Micropure lens group, the Friedman analysis showed differences for all values studied (
p
< 0.05). Correlation coefficients showed that AR is the objective method with the strongest correlation values for all components of refraction for both groups.
Conclusion
The modification of the surfaces of the isofocal lens does not have a negative impact on the refraction obtained by AR compared to a standard monofocal intraocular lens.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
Intraocular lens designs are constantly evolving, trying to obtain more spectacle independence after cataract surgery. This advantage can be linked to some disadvantages, such as optical ...quality decrease. For that reason, it is important to assess, not only the amount of vision provided but also the quality of vision once they are implanted. The purpose of the present work was to compare the visual performance between two monofocal intraocular models: a standard model and a monofocal with enhanced intermediate vision lens.
Methods
Prospective, randomized, comparative study. Sixty adult subjects scheduled to undergo bilateral cataract surgery and IOL implantation were randomized to receive one of the two IOLs in both eyes at Miranza IOA, Madrid, Spain (group A: monofocal with enhanced intermediate vision lens and group B: standard monofocal lens). Monocular outcomes (right eyes) determined 1 and 3 months postoperatively were photopic corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), perceived halo, corrected intermediate-distance contrast sensitivity, and higher-order aberrations. The impact of the new IOL in the postoperative management with autorefraction devices was also evaluated.
Results
No differences were found in CDVA between the two groups. Significant differences were detected between the two lenses evaluated in both total HOA (
p
= 0.028) and internal HOA (
p
= 0.037). Contrast sensitivity and halometry results obtained at 1 month were similar across the two IOL groups.
Conclusion
In patients undergoing cataract surgery, monofocal with enhanced intermediate vision IOL offered similar distance performance and contrast sensitivity along with perceived HOA and halos compared with the standard monofocal IOLs tested.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
To evaluate the optical and aberrometric outcomes of an enhanced monofocal intraocular lens (ISOPure) compared with those of a standard monofocal lens (MicroPure) having the same platform and ...material.
Methods
A prospective, comparative and randomised clinical study. A total of 28 eyes of 28 patients were randomly assigned to either group. Monocular visual acuity (VA) was measured at distance and intermediate under photopic and mesopic conditions. Aberrometry was analysed for 3.0‐, 4.0‐, 4.5‐ and 5.0 mm pupils. The contrast sensitivity defocus curve was measured for 3.0‐ and 4.5‐mm pupils, while the modulation transfer function (MTF) and Strehl ratio (SR) were assessed with a double‐pass system. All measurements were performed monocularly 3 months after surgery.
Results
No significant differences were found for distance VA. Under photopic conditions, intermediate VA was better with the ISOPure lens, while no significant differences were found between the lenses under mesopic conditions. Internal and total aberrations were higher for the ISOPure lens. No significant differences were found for corneal aberrations. Additionally, both the contrast sensitivity defocus curve and optical quality showed similar behaviour for each lens, with the MTF cut‐off frequency exceeding 30 c/deg in both cases.
Conclusion
The isofocal ISOPure lens enhanced intermediate VA without affecting distance VA under photopic conditions. Moreover, there were no significant differences in visual quality between the ISOPure and MicroPure lenses, despite the former exhibiting higher internal and total aberrations than the monofocal model.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Purpose: To examine and assess the halos generated in distance vision by multifocal intraocular lenses (IOLs) using both in vitro objective and in vivo subjective methods.
Setting: The objective ...method was carried out in the optics laboratory of the Applied Optics and Image Processing Group (Universitat Politècnica de Catalunya -Barcelona). The psychophysical and subjective methods were carried out in the Instituto de Oftalmología Avanzada Madrid Innova Ocular.
Design: Optical bench results and prospective evaluation of consecutive cases.
Methods: The IOLs examined were TECNIS
®
one-piece bifocals with addition powers of +4.00 D, +3.25 D, and +2.75 D and the trifocals AT-LISA-tri
®
and FineVision
®
. In the objective assessment, we examined halos around the far focus images of a pinhole formed by each IOL in an optical bench. For the in vivo study, we recruited 100 patients who had been bilaterally implanted one month earlier with the IOLs under study. Participants were subjected to psychophysical halometry (Halo v1.0) on the eye with better, distance-corrected, visual acuity and were required to subjectively grade halos by responding to the question "How much do halos bother you?"
Results: The objective method revealed that the halo size increased with addition power and that the two trifocals gave rise to a double-halo pattern. Scores in the halometry also indicated a direct relationship between the halo size and addition power. The subjective results indicated fewer complaints about halos associated with the trifocal than bifocal IOLs.
Conclusions: The addition power of the tested IOLs affected both laboratory-measured and patient-perceived halos. Trifocal lenses generated fewer complaints about halos.
Precise: Multifocal intraocular lenses (MIOLs) give rise to halos observed by patients under conditions of dim lighting. This study compares laboratory characterized halos generated by five MIOLs with patient-perceived halos.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The purpose was to review and document the methods used to calculate the power of the intraocular lens (IOL) to be implanted in cataract surgery in the specific scenario of eyes with keratoconus. ...This review included all scientific articles published in English that focused on the parameters and formulas used to calculate the power of the IOL to be implanted in eyes with keratoconus undergoing cataract surgery. There are few publications that show in detail how IOL power is calculated in these particular cases. If the keratometric value used was based on the standard refractive index (1.3375), it resulted in a postoperative refractive error with a tendency to hyperopia. The SRK/T formula yielded the best outcomes. The greater the severity of keratoconus the greater was the deviation of the postoperative refractive status from the target outcome.
Purpose: To evaluate the agreement between the biometric measurements used to calculate the size of the implantable collamer lenses (ICL) with different technologies: swept-source optical coherence ...tomography, spectral domain optical coherence tomography, and Scheimpflug tomography. Methods: This retrospective observational study included subjects undergoing refractive surgery with posterior chamber phakic IOL implantation to correct their myopia. The anterior chamber depth (ACD) and the horizontal white to white (WTW) or the angle to angle (ATA) distance were measured with the following four devices: the IOLMaster 700 biometer (Carl Zeiss Meditec, Jena, Germany), based on swept-source optical coherence tomography; the Cirrus and Visante optical coherence tomographs (Carl Zeiss Meditec) based on low-coherence interferometry; and the Pentacam rotating Scheimpflug camera (Oculus, Wetzlar, Germany). Results: In the horizontal corneal diameter measurements, there were statistically significant differences between Pentacam-IOLMaster 700 pair (P < 0.001) and Pentacam-Visante pair (P < 0.001). WTW from CIRRUS showed the lowest correlation when paired with Pentacam and IOLMaster 700 (R2 = 0.452 and 0.385 for Visante and R2 = 0.494 and 0.426 for Cirrus). Regarding the linear correlation of the ACD measurements, all pairs of devices were statistically significant and all of them showed a very good correlation index. Conclusion: There is a good agreement between the different devices under evaluation for ACD measurements. As for WTW, the values measured with the different devices showed large discrepancies with low correlation levels, especially when comparing the tomographs with the other devices under evaluation.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To study the agreement between manifest refraction and objective refraction measured with two autorefractor models and an aberrometer in eyes implanted with a trifocal diffractive intraocular lens ...(IOL).
IOA Madrid Innova Ocular, Madrid, Spain.
Prospective comparative cohort study.
An autorefractor keratometer (KR-8800), based on a Scheiner double pinhole, and a 3-dimension wavefront topography aberrometer system (OPD-Scan III), based on the scanning-slit retinoscopy principle, were used to obtain objective refraction readings. In addition, lower-order Zernike coefficients (Z) were used to calculate objective refraction. A set of 7 different results was obtained in power vector notation (spherical equivalent SE, Jackson cross-cylinder, axes at 180 degrees and 90 degrees J0 and Jackson cross-cylinder, axes at 45 degrees and 135 degrees J45) for 7 different methods: manifest refraction, autorefraction obtained with the autorefractor keratometer, WF-P (Z-based objective refraction for the photopic pupil), WF-M (Z-based objective refraction for the mesopic pupil), WF-4 (Z-based objective refraction for a 4.0 mm pupil), OPD-C (autorefraction measured with the 3-dimension wavefront topography aberrometer system under photopic conditions), and OPD-M (autorefraction measured with the 3-dimension wavefront topography aberrometer system under mesopic conditions).
The study comprised 102 eyes from 51 cataract patients who underwent binocular implantation of a diffractive trifocal IOL (FineVision POD F). All 6 objective methods yielded more negative SE values than manifest refraction (P < .001). As for the astigmatism components (J0 and J45), only autorefraction (P = .003) and OPD-M (P < .001) differed significantly from manifest refraction. The best and worst correlation for the SE component were intraclass correlation coefficient (ICC) = 0.70 (for WF-M) and ICC = 0.48 (for WF-4).
Objective methods tend to yield more negative sphere values than manifest refraction.
Purpose:
To develop a new method that makes it easy to detect accuracy deficiencies of any intraocular lens (IOL) power calculation formulas and to test it on 9 different formulas.
Setting:
IOA, ...Madrid, Spain.
Design:
Retrospective observational case series.
Methods:
This study's first stage included 3519 eyes from 3519 candidates for cataract surgery for which frequency distributions for the following biometric eye parameters were computed: axial length (AL), anterior chamber depth (ACD), lens thickness (LT), white-to-white (WTW), and mean corneal radius (Rm). The resulting data for each parameter were fifth, 25th, 75th and 95th percentiles, which allowed definition of the corresponding normality range. In a second stage, the new graphic-representation method was tested for 9 different formulas in a sample of 70 eyes undergoing cataract surgery with multifocal IOL (mIOL) implantation.
Results:
Normality ranges (defined as the 25th to 75th percentile interval) were 22.84 to 24.42 mm for AL, 2.86 to 3.39 mm for ACD, 4.36 to 4.88 mm for LT, 11.64 to 12.19 mm for WTW, and 7.52 to 7.87 mm for Rm, with lower sizes in women. No significant differences were found among the 9 formulas for percentage of eyes in ±0.50 diopters (D) (
P
= .82) or ±1.00 D (
P
= .97). The graphical method showed less accuracy in ±0.50 D for ACDs from 2.46 to 2.85 mm (5th to 25th percentile) for several formulas (
P
< .05).
Conclusions:
Nine formulas showed nonsignificant differences in the general predictability for a sample of eyes that were candidates to mIOL implantation. Predictability in this sample decreased for short ACDs.
Purpose
In the event that any ocular parameter involved in the calculation of intraocular lens power could not be properly measured in one eye, it is important to know whether clinically relevant ...differences between both eyes can be expected. The aim of this work is to evaluate the symmetry of interocular biometric parameters.
Methods
This was a prospective, cross-sectional study involving 4090 subjects. Patients underwent consecutive swept-source optical biometry performed with an IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany). The biometric parameters that were evaluated were: axial length (AL), mean anterior curvature (Rm), anterior chamber depth (ACD), crystalline lens thickness (LT), central corneal thickness (CCT) and white-to-white (WTW). The Chang–Waring chord distance (CWC-D) and the Chang–Waring chord angle (CWC-A) were also evaluated.
Results
There is an excellent correlation between both eyes for almost all the biometric parameters under study, with the exception of the CWC. Agreement for AL was better for eyes shorter than 24 mm. The linearity of the OD-vs-OS relationship can be correctly assumed for all parameters (Cusum test:
p
> 0.05 in all cases).
Conclusion
There are no clinically significant interocular differences for the biometric parameters under study, although for all of them, except the LT, statistically significant differences did arise. In the case of AL, moderate differences can be expected in eyes larger than 24 mm.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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