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Purpose: To compare the visual performance of prototype contact lenses which extend depth-of-focus (EDOF) by deliberate manipulation of multiple higher-order spherical aberration terms and a commercially-available center-near lens (AIR OPTIX Aqua Multifocal, AOMF). Methods: This was a prospective, cross-over, randomized, single-masked (participant), short-term clinical trial where 52 participants (age 45–70 years) were stratified as low, medium or high presbyopes and wore EDOF and AOMF on different days. Objective measures comprised high and low contrast visual acuity (HCVA/LCVA, log MAR), and contrast sensitivity (log units) at 6 m; HCVA at 70 cm, 50 cm and 40 cm and stereopsis (seconds of arc) at 40 cm. HCVA at 70 cm, 50 cm and 40 cm were measured as “comfortable acuity” rather than conventional resolution acuity. Subjective measures comprised clarity-of-vision and ghosting at distance, intermediate and near, overall vision satisfaction and ocular comfort (1–10 numeric rating scale) and lens purchase (yes/no response). Statistical analysis included repeated measures ANOVA, paired t-tests and McNemar's test. Results: Significant differences between lens types were independent of strata (p ≥ 0.119). EDOF was significantly better than AOMF for HCVA at 40 cm (0.42 ± 0.18 vs. 0.48 ± 0.22, p = 0.024), stereopsis (98 ± 88 vs. 141 ± 114, p

Purpose To evaluate the repeatability of power profiles measured on NIMO TR1504 (Lambda-X, Belgium) and investigate the effects of lens decentration on the power profiles for single vision (SV), bifocal (BF) and multifocal (MF) contact lenses. Methods Accuracy of the sphere power was evaluated using single vision BK-7 calibration glass lenses of six minus and six plus powers. Three SV and four BF/MF contact lenses – three lenses each, were measured five times to calculate the coefficients of repeatability (COR) of the instrument. The COR was computed for each chord position, lens design, prescription power and operator. One lens from each type was measured with a deliberate decentration up to ±0.5 mm in 0.1 mm steps. Results For all lenses, the COR varied across different regions of the half-chord position. In general, SV lenses showed lower COR compared to the BF/MF group lenses. There were no noticeable trends of COR between prescription powers for SV and BF/MF lenses. The shape of the power profiles was not affected when lenses were deliberately decentered for all SV and PureVision MF lenses. However, for Acuvue BF lenses, the peak to trough amplitude of the power profiles flattened up to 1.00 D. Conclusion The COR across the half-chord of the optic zone diameter was mostly within clinical relevance except for the central 0.5 mm half-chord position. COR were dependent on the lens type, whereby BF/MF group produced higher COR than SV lenses. The effects of deliberate decentration on the shape of power profiles were pronounced for lenses where the profiles had sharp transitions of power.

espanolObjetivo Comparar los perfiles de refraccion periferica y aberracion esferica en tres meridianos del campo visual de 16 lentes de contacto (LC) comerciales de prueba monofocales (VS), bifocales (BF) y multifocales (MF), con control de vision simple. Metodo Colocamos aleatoria y contralateralmente a cuarenta participantes [44,2±2,4 anos, SE: −0,5 a −4,5 D]: 6 LC monofocales [Air Optix Aqua (control), Acuvue Oasys, Biofinity, Clariti, Night & Day y Proclear], 3 bifocales [Acuvue Bifocal con adicion baja y alta, MiSight] y 8 MF [Proclear D & N con adicion de 1,5 y 2,5D; AirOptix, PureVision con adicion baja y alta]. Realizamos la refraccion periferica en los meridianos horizontal, oblicuo y vertical, con lentillas en un ojo utilizando el BHVI-EyeMapper. Se analizaron los vectores de potencia M, J0, J45 y el coeficiente de aberracion esferica. Se compararon los perfiles de refraccion periferica y aberracion esferica de las LC de prueba con los perfiles de las LC de control utilizando los coeficientes de curvatura y pendiente. Resultados En comparacion con el control, observamos un cambio hiperopico periferico relativo (M), un coeficiente de curvatura J0 menos negativo en el meridiano horizontal, un coeficiente de curvatura J0 menos positivo en el meridiano vertical, un coeficiente de curvatura J45 menos negativo en el meridiano oblicuo, y un coeficiente de curvatura de aberracion esferica mas positivo en la mayoria de meridianos con las lentillas Acuvue Bifocal y todas las lentillas multifocales de diseno centro-cerca. Para las lentillas multifocales centro-lejos la direccion de los coeficientes de curvatura de los mismos componentes de refraccion y aberracion fue opuesta a la de las lentillas centro-cerca. Las mayores diferencias en cuanto a coeficientes de pendiente, al compararse con el control, se encontraron en las lentillas Acuvue Bifocal y en todas las lentillas multifocales para el componente refractivo M y el coeficiente de aberracion esferica en el meridiano del campo visual horizontal, siendo las lentillas Acuvue Bifocal y las multifocales centro-cerca las que mostraron mas coeficientes positivos, y las lentillas centro-lejos las que reflejaron mas coeficientes negativos. Conclusion Al colocarse en un solo ojo, las diferentes lentillas comerciales producen diferencias en cuanto a direccion y magnitud de los perfiles de refraccion periferica y aberracion esferica en los diferentes meridianos del campo visual. Esta informacion puede ser relevante para el desarrollo refractivo y el control de la miopia. EnglishPurpose To compare the peripheral refraction and spherical aberration profiles along three visual field meridians of 16 commercial single vision (SV), bifocal (BF) and multifocal (MF) test contact lenses with a single vision control. Method Forty-four participants [24.2±2.4 years, SE: −0.50 to −4.50D] were randomly fitted, contra-laterally, with 6 SV's [Air Optix Aqua (control), Acuvue Oasys, Biofinity, Clariti, Night & Day and Proclear], 3 BF's [Acuvue Bifocal low and high add, MiSight] and 8 MF's [Proclear D & N in 1.5 and 2.5D adds; AirOptix, PureVision low & high adds]. Peripheral refraction was performed across horizontal, oblique and vertical meridians, with lenses on eye using the BHVI-EyeMapper. The power vectors M, J0, J45 and the spherical aberration coefficient were analysed. The peripheral refraction and aberration profiles of the test lenses were compared with the profiles of the control lens using curvature and slope coefficients. Results Compared to the control, a relative peripheral hyperopic shift (M), a less negative J0 curvature coefficient along the horizontal meridian, a less positive J0 curvature coefficient along the vertical meridian, a less negative J45 curvature coefficient along the oblique meridian and a more positive spherical aberration curvature coefficient along most meridians was seen with the Acuvue Bifocal and all center-near multifocal lenses. For the center-distance multifocal lenses the direction of the curvature coefficients of the same refraction and aberration components was opposite to that of the center-near lenses. The greatest differences in the slope coefficients when compared to the control were found for the Acuvue Bifocal lenses and all multifocal contact lenses for the refractive component M and the spherical aberration coefficient along the horizontal visual field meridian, with the Acuvue Bifocal and the center-near multifocal lenses having more positive coefficients and the center-distance lenses having more negative coefficients. Conclusion When worn on eye, different commercially available lens types produce differences in the direction and magnitude of the peripheral refraction and spherical aberration profiles along different visual field meridians. This information may be relevant to refractive development and myopia control.

Purpose: To compare the visual performance of prototype contact lenses designed via deliberate manipulation of higher-order spherical aberrations to extend-depth-of-focus with two commercial multifocals, after 1 week of lens wear. Methods: In a prospective, participant-masked, cross-over, randomized, 1-week dispensing clinical-trial, 43 presbyopes [age: 42–63 years] each wore AIROPTIX Aqua multifocal (AOMF), ACUVUE OASYS for presbyopia (AOP) and extended-depth-of-focus prototypes (EDOF) appropriate to their add requirements. Measurements comprised high-contrast-visual-acuity (HCVA) at 6 m, 70 cm, 50 cm and 40 cm; low-contrast-visual-acuity (LCVA) and contrast-sensitivity (CS) at 6 m and stereopsis at 40 cm. A self-administered questionnaire on a numeric-rating-scale (1–10) assessed subjective visual performance comprising clarity-of-vision and lack-of-ghosting at various distances during day/night-viewing conditions and overall-vision-satisfaction. Results: EDOF was significantly better than AOMF and AOP for HCVA averaged across distances (p ≤ 0.038); significantly worse than AOMF for LCVA (p = 0.021) and significantly worse than AOMF for CS in medium and high add-groups (p = 0.006). None of these differences were clinically significant (≤2 letters). EDOF was significantly better than AOMF and AOP for mean stereoacuity (36 and 13 seconds-of-arc, respectively: p ≤ 0.05). For clarity-of-vision, EDOF was significantly better than AOP at all distances and AOMF at intermediate and near (p ≤ 0.028). For lack-of-ghosting averaged across distances, EDOF was significantly better than AOP (p

Purpose: Myopia is considered to be the most common refractive error occurring in children and young adults, around the world. Motivated to elucidate how the process of emmetropization is disrupted, potentially causing myopia and its progression, researchers have shown great interest in peripheral refraction. This study assessed the effect of the myopia type, either refractive or axial, on peripheral refraction and aberration profiles. Methods: Using customized schematic eye models for myopia in a ray tracing algorithm, peripheral aberrations, including the refractive error, were calculated as a function of myopia type. Results: In all the selected models, hyperopic shifts in the mean spherical equivalent (MSE) component were found whose magnitude seemed to be largely dependent on the field angle. The MSE profiles showed larger hyperopic shifts for the axial type of myopic models than the refractive ones and were evident in -4 and -6 D prescriptions. Additionally, greater levels of astigmatic component (J180) were also seen in axial-length-dependent models, while refractive models showed higher levels of spherical aberration and coma. Conclusion: This study has indicated that myopic eyes with primarily an axial component may have a greater risk of progression than their refractive counterparts albeit with the same degree of refractive error. This prediction emerges from the presented theoretical ray tracing model and, therefore, requires clinical confirmation.

Purpose To compare the contributions of single vision (SVCL) and multifocal contact lenses (MFCL) to the relative peripheral refraction (RPR) profiles obtained via an autorefractor and an aberrometer in a pilot study. Methods Two instruments, Shin-Nippon NVision K5001 (SN) and COAS-HD, were modified to permit open field PR measurements. Two myopic adults (CF, RB) were refracted (cycloplegia) under eight conditions: baseline (no CL); three SVCLs: Focus Dailies® (Alcon, USA), PureVision® (Bausch & Lomb, USA) and AirOptix® (Alcon, USA); and four MFCLs: AirOptix® (Alcon, USA), Proclear® Distant and Near (Cooper Vision, USA), and PureVision® (Bausch & Lomb, USA). CLs had a distance prescription of −2.00D and for MFCLs, a +2.50D Add was selected. Five independent measurements were performed at field angles from −40° to +40° in 10° increments with both instruments. The COAS-HD measures were analyzed at 3 mm pupil diameter. Results are reported as a change in the relative PR profile, as refractive power vector components: M, J180, and J45. Results Overall, at baseline, M, J180 and J45 measures obtained with SN and COAS-HD were considerably different only for field angles ≥±30°, which agreed well with previous studies. With respect to M, this observation held true for most SVCLs with a few exceptions. The J180 measures obtained with COAS-HD were considerably greater in magnitude than those acquired with SN. For SVCLs, the greatest difference was found at −40° for AirOptix SV (ΔCF = 3.20D, ΔRB = 1.56D) and for MFCLs it was for Proclear Distance at −40° (ΔCF = 2.58D, ΔRB = 1.39D). The J45 measures obtained with SN were noticeably different to the respective measures with COAS-HD, both in magnitude and sign. The greatest difference was found with AirOptix Multifocal in subject RB at −40°, where the COAS-HD measurement was 1.50D more positive. In some cases, the difference in the RPR profiles observed between subjects appeared to be associated with CL decentration. Conclusion For most test conditions, distinct differences were observed between the RPR measures obtained with the two modified instruments. The differences varied with CL design and centration. Although the pilot study supports the interchangeable use of the two instruments for on- and off-axis refraction in unaided eyes or eyes corrected with low/no spherical aberration; we advocate the use of the COAS-HD over the SN for special purposes like refracting through multifocal CLs.