BCLA CLEAR Presbyopia: Definitions.

Presbyopia is often the first sign of ageing experienced by humans. Standardising terminology and adopting it across the BCLA CLEAR Presbyopia reports, improves consistency in the communication of the evidence-based understanding of this universal physiological process. Presbyopia can be functionally and psychologically debilitating, especially for those with poor access to eyecare. Presbyopia was defined as occurring when the physiologically normal age-related reduction in the eye's focusing range reaches a point that, when optimally corrected for far vision, the clarity of vision at near is insufficient to satisfy an individual's requirements. Accommodation is the change in optical power of the eye due to a change in crystalline lens shape and position, whereas pseudo-accommodation is the attainment of functional near vision in an emmetropic or far-corrected eye without changing the refractive power of the eye. Other definitions specific to vision and lenses for presbyopia were also defined. It is recommended that these definitions be consistently adopted in order to standardise future research, clinical evaluations and education.

Eyelid squinting improves near vision in against-the-rule and distance vision in with-the-rule astigmatism in pseudophakic eyes: an eye model experimental study.

BACKGROUND: To elucidate whether eyelid squinting improves near and distance vision in against-the-rule (ATR) and with-the-rule (WTR) simple myopic astigmatism in pseudophakic eyes. METHODS: A refraction-model eye was mounted on a wavefront analyzer. The eyelid fissure was simulated using a slit placed horizontally in front of the model eye. Four different refractive statuses [- 1.50 diopters (D) and - 3.00 D of both WTR and ATR simple myopic astigmatism] were set using cylindrical lenses. For each refractive status (emmetropia, - 1.50 D WTR, - 1.50 D ATR, - 3.00 D WTR, and - 3.00 D ATR astigmatism), wavefront aberrations were measured, both with and without the slit, 40 times each. RESULTS: The 2 mm horizontal slit caused a hyperopic focus shift (+ 6.69 µm) in - 1.50 D WTR astigmatism, whereas, in - 1.50 D ATR astigmatism, it caused a myopic focus shift (- 2.01 µm). The astigmatism was decreased in the ATR astigmatism groups and increased in the emmetropia and WTR astigmatism groups, respectively. Total aberrations were decreased in the emmetropia and WTR astigmatism groups and increased in the ATR astigmatism groups. When the reference plane was set to the near plane, total aberrations were decreased in the ATR astigmatism groups. CONCLUSION: As the horizontal slit was placed in front of the model eye, the focus moves nearer in ATR astigmatism and farther in WTR astigmatism. These effects of eyelid cause improvement of near vision of pseudophakic eyes with ATR astigmatism.

[Presbyopia and refractive surgery]. / Presbytie et chirurgie réfractive.

Presbyopia is the progressive loss of accommodation. Accommodation is a quick, precise and involuntary action which enables the eye to change the power of the young crystalline lens to see clearly at all distances. Presbyopia is and age-linked physiologic phenomenon: it results from aging of the lens, which loses its elasticity, gradually becomes rigid and loses the ability to accommodate. Presbyopia has attained a prevalence of 80% in Europe and is increasing regularly due to the aging of the population. Various surgical techniques can be proposed. Indications depend on age, ophthalmological exam, and any associated ametropia. The main techniques act by either changing the curvature of the cornea with laser or with an intrastromal inlay to create pseudoaccomodation, or by intraocular lens surgery with a multifocal or accommodating IOL. Once the surgical choice has been made, the information must be clearly conveyed and consent obtained.

Comparison of objective accommodation in phakic and pseudophakic eyes between age groups.

PURPOSE: To compare objective accommodation of phakic and pseudophakic eyes between two different age groups. METHODS: Eighty-three eyes (83 participants aged ≥ 40 years) with a visual acuity of 20/25 or better, and refractive error < spherical - 1.0 diopters (D) and cylindrical 1.0 D, were included. Forty-four patients had undergone phacoemulsification and monofocal intraocular lens implantation and were examined 6 months post-surgery. Participants were divided into groups 1 (pseudophakic, age < 60 years), 2 (pseudophakic, ≥ 60 years), 3 (phakic, < 60 years), and 4 (phakic, ≥ 60 years). Objective accommodation and pupil diameter to 2.0- and 3.0-D stimuli were measured with a binocular open-field autorefractor. RESULTS: The mean objective accommodation was 0.29 ± 0.47 D, 0.01 ± 0.21 D, 1.00 ± 0.88 D, and 0.01 ± 0.13 to a 2.0-D stimulus, and 0.26 ± 0.51 D, - 0.06 ± 0.21 D, 1.42 ± 1.21 D, and - 0.06 ± 0.21 to a 3.0-D stimulus in groups 1, 2, 3, and 4, respectively. For both stimuli, the values in group 1 exceeded those in groups 2 and 4, and were smaller than those in group 3, while the values in group 3 exceeded those in groups 2 and 4. The mean pupillary diameter was - 0.5 ± 0.8 mm, - 0.3 ± 0.8 mm, - 0.6 ± 0.5 mm, and - 0.6 ± 0.9 mm to a 2.0-D stimulus, and - 0.6 ± 0.8 mm, - 0.6 ± 0.8 mm, - 0.9 ± 0.5 mm, and - 1.0 ± 1.1 mm to a 3.0-D stimulus in groups 1, 2, 3, and 4, respectively. There was significant correlation between objective accommodation and changes of pupil size for both stimuli. CONCLUSION: Age seems to play a role in objective accommodation among relatively young pseudophakic patients.

[Wavefront and accommodation parameters under different conditions of correction in myopia and hyperopia]. / V.V., Parametry volnovogo fronta i akkomodatsii v raznykh usloviiakh korrektsii pri miopii i gipermetropii.

PURPOSE: To compare the wavefront and accommodation parameters without correction and in soft contact lenses (SCL) in natural and cycloplegic conditions in eyes with myopia and hyperopia. MATERIAL AND METHODS: A total of 142 myopic (mean -5.6±1.4 D) and 48 hyperopic (mean +3.5±1.1 D) eyes were examined in 95 patients aged 5-32 years (mean age 16.9±0.9 years) to compare the wavefront aberrations without correction and with different SCL before and after cycloplegia (two drops of cyclopentolate hydrochloride 1%). The device was set up for 4 mm zone for both narrow and wide pupils. To compare the accommodation parameters under different correction conditions, 85 patients aged 8-23 years (mean age 14.9±0.6 years) with average myopia of (-)5.27±1.4D (123 eyes) and average hyperopia of +3.53±1.2 D (46 eyes) were chosen from the study group. Among the measured parameters are objective accommodative response (OAR), relative accommodation reserves (RAR), pseudoaccumulation amplitude (PA), higher-order aberrations: RMSHOAs, 6-9 Trefoil, 7-8 Coma, spherical aberration (SA). RESULTS: In myopic eyes with SCL Coma 7 decreases, Coma 8 increases with transition to positive values, and Trefoil 9 increases. In hyperopic eyes, trefoil 6 decreases, Coma 7-8 go negative. In myopic or hyperopic eyes with SCL, SA goes from positive to negative. In both myopia and hyperopia, accommodation and PA rates are higher in SCL than in glasses. CONCLUSION: SCL change certain wavefront parameters for myopia and hyperopia in different ways. The accommodation parameters in SCL are elevated in both myopia and hyperopia. The negative spherical aberration induced by contact lenses improves the accommodative response. The revealed features should be considered in the development of correction methods that target refractogenesis.

Pseudo-accommodation in non-amblyopic children after bilateral cataract surgery and implantation with a monofocal intraocular lens: prevalence and possible mechanisms.

BACKGROUND: Some pseudophakic patients implanted with a monofocal intraocular lens (IOL) have good near visual acuity (VA) with their distance correction. The objective was to evaluate the prevalence of pseudo-accommodation in children after bilateral cataract surgery, without amblyopia, and to define its mechanisms. METHODS: Observational study that took place in a pediatric ophthalmology department, Paris, France. A total of 68 eyes were included, 40 from 23 children and 28 from 14 adults, with a corrected distance VA above 20/25 and a normal near VA (20/25) with +3 addition. Pseudo-accommodation was defined as a near VA better than 20/50 with the distance correction and without addition. Prevalence of pseudo-accommodation was calculated in each group. In order to determine the possible mechanisms of pseudo-accommodation in children, we compared children with pseudo-accommodation and adults without pseudo-accommodation regarding several parameters: refraction, axial length, corneal topography, aberrometry, pupillary diameter and IOL shift after cyclopentolate instillation. RESULTS: Among the children group, 36 (90 %) had pseudo-accommodation versus 2 (7 %) in the adult group. We found that spherical equivalent, implant power, corneal multifocality and corneal higher-order aberrations (mainly coma and trefoil) were significantly higher in the pseudo-accommodation group, while pupil diameter and implant shift were not significantly different. CONCLUSIONS: Pseudo-accommodation has a high prevalence among non-amblyopic pseudophakic children. Several possible mechanisms have been found to explain pseudo-accommodation in children: a high power of the IOL and a small axial length, maximizing the effect of the IOL shift, corneal multifocality and corneal higher-order aberrations.

Presbyopic correction on the cornea.

PURPOSE: The aim of this systematic review was to synthesize and appraise the evidence of the benefits of presbyopic correction on the cornea for visual function. SUMMARY: Comprehensive search was conducted in MEDLINE using keywords like "presbylasik", "presbyopic refractive surgery", "corneal pseudoaccommodation" and "corneal multifocality". We reviewed corrected and uncorrected visual acuities for distance and near (uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), distance corrected near visual acuity (DCNVA), corrected near visual acuity (CNVA)), along with the refractive outcomes in spherical equivalent (SE) and astigmatism comparing the differences observed between preoperative myopic and hyperopic patients, as well as among techniques. Thirty-one studies met the inclusion and quality criteria. Monovision provides excellent distance and near uncorrected acuities, but with a 17% retreatment and a 5% reversal rate. Initial multifocal ablations result in 12% loss of 2 or more lines of CDVA, and a 21% retreatment rate. Laser Blended Vision provides excellent UDVA, but with a 19% retreatment rate. Initial experiences with Supracor show moderate predictability and a 22% retreatment rate. Intracor results in 9% loss of 2 or more lines of CDVA. KAMRA provides excellent UDVA, with only a 1% retreatment rate, but a 6% reversal rate. Initial experiences with PresbyMAX provided excellent UNVA and DCNVA, showing excellent predictability and a 1% reversal rate. CONCLUSIONS: The findings have implications for clinicians and policymakers in the health-care industry and emphasize the need for additional trials examining this important and widely performed clinical procedure.

Comparisons of amplitude of pseudoaccommodation with aspheric yellow, spheric yellow, and spheric clear monofocal intraocular lenses.

PURPOSE: To determine the amplitude of pseudoaccommodation and higher-order aberrations with three types of implanted monofocal intraocular lenses (IOLs): aspheric yellow (IQ); spheric yellow (NT); and spheric clear (AT). SETTING: Department of Ophthalmology, Nara Medical University, Nara, Japan. METHODS: We studied 60 patients who underwent small incision phacoemulsification with the implantation of a monofocal IQ, NT, or AT IOL. The pseudoaccommodation was measured by the lens-loading method, and the postoperative ocular higher-order aberrations were measured with a Hartmann-Shack wavefront analyzer through natural and 4 mm pupils. RESULTS: Sixty eyes of 60 patients were studied. The average amplitude of the pseudoaccommodation was 0.45±0.24 D with the IQ IOL, which was significantly lower than that with the AT IOL at 0.81±0.37 D (Tukey's test; P<0.01). The differences in the amplitude of the pseudoaccommodation between the IQ and the NT IOLs, and between the NT and the AT IOLs were not significant (Tukey's test; P>0.05). The degree of spherical aberration was significantly different for the IQ, NT, and AT lenses (analysis of variance, P=0.016). The spherical aberration through the IQ IOL was significantly lower than that through the NT and the AT IOLs (Tukey's test; P<0.01). The fourth-order RMS (root mean square) aberration of the IQ lens was also significantly lower than that of the NT and AT IOLs (Tukey's test; P<0.01). CONCLUSION: Our results suggest that the spherical aberration and selective spectral transmission of IOLs may work together to increase the amplitude of the pseudoaccommodation.