To review binocular and accommodative disorders documented after corneal or intraocular refractive surgery, in normal healthy prepresbyopic patients. A bibliographic revision was performed; it ...included works published before 1st July 2017 where accommodation and/or binocularity was assessed following any type of refractive surgical procedure. The search in Pubmed yielded 1273 papers, 95 of which fulfilled the inclusion criteria. Few publications reporting binocular vision and/or accommodative changes after refractive surgery in normal subjects were found. The reduction in fusional vergence is the most frequently reported alteration. Anisometropia is an important risk factor for postoperative binocular vision‐related complaints. Most diplopia‐related visual complaints, irrespective of the surgical procedure, were in fact misdiagnosed preoperative disorders. The preoperative evaluation of patients seeking spectacle/contact lens independence should include a complete binocular and accommodation assessment where parameters such as the phoric posture, accommodative amplitude and facility, near point of convergence, fusional reserves and accommodative convergence/accommodation coefficient are measured. This would allow the identification of risk factors that could compromise the success of the refractive surgery and cause clinical symptoms.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Purpose
To implement a pure power vector method for monocular subjective refraction using a regular phoropter with the only modification being the inclusion of a Stokes lens. The proposed methodology ...was tested with three different Stokes lenses, and the results were compared with conventional clinical refraction procedures.
Methods
Power vector subjective refraction was performed by attaching a Stokes lens to the Risley prism holder. Stokes lenses allow for pure astigmatic compensation in the form of the J0, J45 components while the spherical lenses in the phoropter allow determination of the spherical component in the form of M (spherical equivalent). The proposed routine is presented step‐by‐step using three Stokes lenses having different astigmatic powers.
Results
Monocular subjective refraction was performed on 26 healthy subjects with a mean age of 44 ± 16 years, mean spherical equivalent of −0.56 D (range −5.50 to +2.38 D) and refractive astigmatism ≤1.50 D. No differences were found between the results obtained with the conventional technique versus the vector‐based procedure for the spherical equivalent (p = 0.28) or astigmatic components (p = 0.34). In addition, visual acuity (VA) was equivalent through the refractions measured with the conventional and vector procedures (p = 0.12). Repeatability coefficients for J0 and J45 with the new vector methodology were <0.38 D.
Conclusions
The proposed routine could be helpful for cases where it is difficult to get a valid starting point for conventional refraction (e.g., irregular corneas and media opacities), for testing facilities with limited resources/equipment and/or for motivated clinicians who wish to know about alternative methods of refractive error determination.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Purpose
To determine the long-term incidence of pseudophakic retinal detachment (PRD) after phacoemulsification and the weight of the main risk factors in the appearance of such complication in a ...large sample. To implement a customized formula and a software calculation program able to quantify the risk of suffering PRD applicable to all lens extraction patients.
Methods
Retrospective cumulative risk analysis conducted on 178,515 eyes operated under similar conditions in a group of refractive surgery clinics (Clínica Baviera SL) located in a relatively limited geographical area (Spain). A survival analysis was performed and the data were modelled using the Weibull regression to determine the risk over a period of 16 years and to estimate the association of different risk factors: sex, age, axial length (AXL) of the eye, intraoperative posterior capsule rents (PCR), and YAG laser capsulotomies. The resulting estimates were translated into a predictive equation for hazard rates and survival probabilities. Later, an application was developed to make prediction available for the clinical community in order to estimate the potential risk of any hypothetical case before lens surgery.
Results
Globally, 1521 (0.85%) cases of PRD were diagnosed during the period. The risk for PRD was significantly greater in males (5.48 2.94–10.2;
p
< 0.001), in long eyes (1.24 1.21–1.26;
p
< 0.001), and also after posterior capsule rents (13.97 11.61–16.82;
p
< 0.001). Posterior capsule rupture increased the risk of PRD up to fourteen times.
Conclusions
From weaker to stronger impact, age, axial length, sex, and intraoperative posterior capsule rent were significant risk factors for the appearance of PRD after lens extraction.
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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
To evaluate visual function after bilateral implantation of a zonal refractive aspheric multifocal intraocular lens (IOL).
Private practice surgery center, Valencia, Spain.
Cohort study.
Consecutive ...eyes with cataract had bilateral implantation of Lentis Mplus LS-312 multifocal IOLs. Distance, intermediate, and near visual acuities; contrast sensitivity; defocus curves; and a quality-of-vision questionnaire, including presence of halos or dysphotopsia, were evaluated 6 months postoperatively. A control group of age-matched monofocal pseudophakic patients was included to compare contrast sensitivity function.
In the multifocal group, the mean binocular corrected distance visual acuity (logMAR) was -0.04 ± 0.07 at 6 m, 0.11 ± 0.10 at 1 m, and 0.06 ± 0.07 at 40 cm. The defocus curve showed little intermediate vision drop off. Photopic contrast sensitivity for distance was similar to the monofocal IOL contrast sensitivity function, while photopic contrast sensitivity for near and mesopic contrast sensitivity for distance with or without glare was reduced at high frequencies. The mean patient satisfaction was 8.09 ± 1.30 (scale 0 to 10); 84.4% of patients were completely independent of spectacles. Moderate halos, glare, and night-vision problems were reported by 6.2%, 12.5%, and 15.6% of patients, respectively.
The new-generation multifocal IOL provided adequate distance, intermediate, and, to a lesser extent, near vision with high rates of spectacle freedom. Halos occurred, and other photic phenomena should be expected in a small percentage of patients.
No author has a financial or proprietary interest in any material or method mentioned.
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
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
To report the visual, refractive, and clinical outcomes of simultaneous topography-guided partial photorefractive keratectomy (PRK) and corneal collagen crosslinking (CXL) in eyes with keratoconus.
...Private practice surgery center, Dubai, United Arab Emirates.
Retrospective cohort study.
Refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, flat and steep keratometry (K) readings, and complications were evaluated 1, 3, 6, and 12 months postoperatively.
The study enrolled 31 eyes of 31 patients aged 21 to 42 years. All study parameters showed a statistically significant improvement at 3, 6, and 12 months over baseline values. At 12 months, the mean UDVA improved to 0.23 logMAR±0.33 (SD) from 0.79±0.36 logMAR (P<.001) and the CDVA improved to 0.06±0.07 logMAR from 0.28±0.20 logMAR (P<.001). The mean defocus decreased from 3.45±1.60 diopters (D) to 1.88±1.58 D (P<.001). The flat K and steep K readings showed significant flattening. The mean refractive astigmatism decreased from -2.77±1.47 D to -0.98±0.76 D (P<.001). The improvement in study parameters plateaued after 3 months.
Simultaneous topography-guided partial PRK and CXL was effective, safe, and stable in keratoconus patients.
No author has a financial or proprietary interest in any material or method mentioned.
To evaluate the impact on the ocular surface of a daily disposable hydrogel contact lens with high water content compared with two silicone hydrogel daily disposable lenses of lower water content.
...The hydrogel lens assessed was made from nesofilcon A and the silicone hydrogel lenses were made of delefilcon A and stenfilcon A. Contact lens thickness was measured to assess material stability during daily wear, and ocular surface parameters such as tear film osmolarity, tear meniscus area and central corneal thickness were also assessed. Optical quality was analysed for all cases by means of wavefront aberrometry.
The nesofilcon A was shown to be the thinnest lens (p < 0.001), while no differences in lens thickness were found between the two silicone hydrogel lenses (p = 0.495). No significant differences were found in tear film osmolarity, tear meniscus area, central corneal thickness or corneal aberrations, either as a function of the lens measured or time of use (p > 0.05).
In spite of having the thinnest lens and the highest water content, the hydrogel does not significantly impact on tear film and corneal swelling after one day of use in first-time wearers.
Deflectometry is an optical technique for determining properties such as power distribution, wavefront, etc., and measurement of the optical properties of an intraocular lens can provide relevant ...information for clinicians. The aim of the current study was to establish a protocol for measuring lens power maps and profiles of various optical designs of intraocular lenses with a deflectometer based on the phase-shifting Schlieren principle (NIMO TR1504, Lambda-X, Nivelles, Belgium). The results are discussed with respect to accuracy and repeatability, the influence of the use of filters, and whether to consider the intraocular lens as a thin or thick lens.
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.
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