Purpose: To evaluate the effectiveness and patient acceptance of multifocal vision simulation in patients with previous monofocal intraocular lens (IOL) implantation, and to explore their willingness-to-pay (WTP) and willingness-to-accept (WTA) based on the perceived advantages and disadvantages of multifocal vision. Methods: Seventeen patients with previous monofocal IOL implantation participated in this cross-sectional study. The SimVis Gekko device (2EyesVision SL) was used to simulate monofocal (Evaluation B) and multifocal (Evaluation C) visual experiences, compared to their existing vision (Evaluation A). Visual acuity at three distances and defocus curves were measured. Patients responded to inquiries about visual quality in each evaluation, bothersomeness of photic phenomena, probability to select the visual experience, and the monetary value they associated with enhanced WTP or diminished WTA visual quality. Results: The simulations underestimated the visual acuity reported for the IOL in existing literature by one or two lines, depending on the testing distance. This underestimation was more pronounced in defocus curves. However, 70.6% of patients were likely or very likely to opt for multifocal vision, indicating they perceived the benefits of multifocality. The WTP for multifocal vision was twice that of monofocal vision, and the WTP/WTA ratio exceeded 1, suggesting the perceived vision benefits outweighed potential drawbacks. Conclusions: Despite underestimating the expected postoperative visual performance, the multifocal simulation enabled patients to perceive the benefits of multifocal vision to some extent. This system could be beneficial in avoiding potential postoperative complaints, but the possible rise in false-positive results should be considered and evaluated in future research. [ J Refract Surg . 2023;39(12):831–839.]

Purpose: To assess agreement between a new all-in-one non-contact optical biometer based on optical low coherence reflectometry (SW-9000 µm Plus; Suoer) and a swept-source optical coherence tomography biometer (OA-2000; Tomey). Methods: Each eye was scanned three times in a row by each device at random. The measured ocular parameters included central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), axial length (AL), flat keratometry (Kf), steep keratometry (Ks), mean keratometry (Km), astigmatism, corneal diameter (CD), and pupil diameter (PD). The paired t test was used to show the differences between the SW-9000 and OA-2000. Bland-Altman plots and the 95% limits of agreement (LoA) were applied to assess the consistency of the measurements. Results: Sixty eyes from 60 healthy participants were examined, with a mean spherical equivalent refraction of −5.58 ± 2.31 diopters and a mean age of 30.40 ± 6.07 years. The Bland-Altman plots showed high agreement for AL, ACD, LT, Kf, Ks, Km, astigmatism, and CD measurements (95% LoA: −0.06 to 0.04 mm, −0.10 to 0.06 mm, −0.12 to 0.11 mm, −0.30 to 0.29 D, −0.35 to 0.38 D, −0.29 to 0.30 D, −0.30 to 0.34 D, and −0.50 to 0.06 mm, respectively), whereas the agreement for CCT and PD were moderate (95% LoA: 7.12 to 20.43 µm, −0.75 to 1.19 mm, respectively). Conclusions: The new all-in-one non-contact biometer had high agreement with the OA-2000 biometer on the AL, ACD, LT, Kf, Ks, Km, astigmatism, and CD measurements. For most of the ocular parameters assessed, they were clinically interchangeable. [ J Refract Surg . 2023;39(12):825–830.]

Purpose: To explore size, decentration, and eccentricity of effective optical zones (EOZs) in laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), and small incision lenticule extraction (SMILE) and correlate them to higher order aberrations (HOAs). Methods: This was a retrospective chart review of 188 eyes that underwent refractive surgery for compound myopia (61 LASIK, 84 PRK, 43 SMILE). EOZ measurements were determined using 1-year postoperative Pentacam (Oculus Optikgeräte GmbH) tangential difference maps. HOA data were measured using Pentacam wavefront aberration Zernike polynomials. Correlations between EOZs and HOAs were analyzed. Results: The EOZs of LASIK and PRK are smaller than SMILE at 19.54 ± 1.44, 19.39 ± 1.66, and 22.18 ± 2.61 mm 2 , respectively ( P < .001). No difference existed in absolute decentration from corneal vertex ( P = .078) or pupil center ( P = .131), but horizontal and vertical components differed significantly ( P < .001). Smaller EOZ areas were correlated with greater spherical aberration induction (rLASIK = −0.378, rPRK = −0.555, rSMILE = −0.501) and total HOA induction in all groups. Absolute decentration from corneal vertex positively correlated with total HOA (rLASIK = 0.396, rPRK = 0.463, rSMILE = 0.399) and directional vertical coma induction negatively correlated with vertical decentration from the corneal vertex (rLASIK = −0.776, rPRK = −0.665, rSMILE = −0.576) in all groups. Conclusions: SMILE results in a larger EOZ than LASIK and PRK, and absolute decentration remains comparable regardless of surgical reference center, despite horizontal/vertical differences. Surgical planning to ensure adequate EOZ size and centration may reduce induction of HOAs, including spherical aberrations and vertical coma. [ J Refract Surg . 2023;39(11):741–750.]

To investigate the eye rubbing habits of Chinese patients with keratoconus. This study was carried out from 2018 to June 2022 at Shandong Eye Hospital, Qingdao Eye Hospital, and Henan Eye Hospital. The study compared the number of patients who rubbed their eyes between medical records and second time questionnaires, eye rubbing of patients with myopia and patients with keratoconus, and disease severity between patients with keratoconus. A questionnaire survey of ophthalmologists was conducted to determine their degree of awareness that eye rubbing is a risk factor for keratoconus. The study assessed 799 patients with keratoconus and 798 control patients, and 97 ophthalmologists. The average proportion of patients with keratoconus who rubbed their eyes was 31.0% in the medical records with an increasing trend related to the increase in ophthalmologists' awareness, 66.6% after the second follow-up, and 25.4% among patients with myopia. After multivariate analysis, the following variables showed significant results: eye rubbing frequency more than 10 times/day (odds ratio [OR], 9.168; P < .001); rubbing with knuckles (OR, 9.804; P = .001); and prone sleep position (OR, 12.427; P < .001). The proportion of patients who rubbed their eyes with stage IV keratoconus was 71.9%, 18.9% higher than those with stage I, 4.8% higher than stage II, and 17.8% higher than stage III. The proportion of Chinese patients with keratoconus who rubbed their eyes was relatively high. The main reasons for the low proportions reported were lack of attention. Clinical attention should be paid to eye rubbing in patients with keratoconus who should be educated to avoid it. [J Refract Surg. 2023;39(10):712-718.].

To investigate the 12-month outcomes of small incision lenticule extraction (SMILE) with proper head positioning but no reference marking for correcting astigmatism. This was a retrospective cohort study of 3,541 patients (5,953 eyes) who underwent SMILE between July 2010 and April 2021. Patient positioning on the treatment bed was meticulously done in every patient to avoid face turn, head tilt, and chin-up or chin-down posture. The corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), manifest refraction, astigmatic outcomes, and adverse events were evaluated at 1, 3, and 12 months postoperatively. The mean preoperative manifest spherical equivalent and manifest cylinder were -5.15 ± 2.24 diopters (D) (range: -0.13 to -12.88 D) and -1.00 ± 0.77 D (range: -0.25 and -6.00 D), respectively. Of all eyes, 88.4% and 98.6% had the spherical equivalent within ±0.50 and ±1.00 D of emmetropia at 12 months. The percentage of eyes with UDVA of 20/20 or better was 92.5%. Six eyes (0.1%) lost two or more lines of CDVA at the 12-month visit. The predictability of cylinder correction was excellent, with 88.1% within ±0.50 D and 98.9% within ± 1.00 D of astigmatism correction at 12 months. The mean correction index (CI) at 12 months was 1.09 ± 0.45 (range: 0.17 to 4.99), indicating a slight astigmatism overcorrection. The high cylinder group tended to have undercorrection with greater residual astigmatism, whereas the low cylinder group was likely to have overcorrection with lesser residual astigmatism (P < .001). No serious adverse events were observed. SMILE with proper head positioning but no reference marking produces safe, efficient, predictable, and stable outcomes for astigmatism correction over a 12-month period. [J Refract Surg. 2023;39(10):683-692.].

To assess the clinical and aberrometric outcomes of a new Implantable Collamer Lens (EVO Viva ICL; STAAR Surgical) to correct moderate to high myopia and presbyopia. The study included 80 eyes of 40 patients who had bilateral EVO Viva ICL implantation. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, presbyopic add power, binocular through-focus visual acuity, total ocular spherical aberration (SA), coma aberration, and root mean square of ocular higher order aberrations (RMS HOAs) (i-Trace Aberrometer; Tracey Technologies) for a 4.5-mm pupil size were evaluated. The mean binocular postoperative UDVA and CDVA were 0.09 ± 0.19 and 0.02 ± 0.03 logMAR, respectively. The postoperative spherical equivalent was -0.61 ± 0.54 diopters (D). The presbyopic add power reduced from +1.31 ± 0.74 D preoperatively to +0.44 ± 0.58 D after surgery (P < .0001). The mean visual acuity was 0.1 logMAR or better (20/25 or better) across the vergence range from +0.50 to -1.50 D, better than 0.2 logMAR (20/32 or better) up to the vergence of -2.00 D, and remained better than 0.3 logMAR (20/40 or better) up to the vergence of -2.50 D. The total ocular aberrations induced by EVO Viva ICL were -0.34 ± 0.09 µm of SA, 0.24 ± 0.18 µm of coma, and 0.26 ± 0.12 µm of RMS HOAs. The outcomes support that the new ICL might be a good alternative for myopia and presbyopia correction in patients aged between 45 and 55 years. Further studies are needed to evaluate the threshold lens misalignment from which the patient´s visual quality would be affected. [J Refract Surg. 2023;39(9):589-596.].

To assess the effectiveness and characteristics of aspheric monofocal intraocular lenses (IOLs) with different anti-misalignment designs. Three types of anti-misalignment IOLs (with aspheric balance curve design, ZO optic design, and high-order optical aspheric surface design) and no anti-misalignment IOLs were involved. From each type of these IOLs, +8.00, +17.00, and +26.00 diopter (D) lenses were used for detection at the 3- and 4.5-mm apertures. The modulation transfer function (MTF) and 50% of the maximum value of the MTF (MTF50) were measured while IOLs were centered, decentered by 0.3, 0.5, and 0.7 mm, and tilted by 3, 5, and 7 degrees. Within the average clinical range of IOL malpositions (0.3-mm decentration or 3.00-D tilt), the anti-misalignment design slightly reduced the negative effect of decentration and tilt (P = .1845 and .6495, t test) on the optical performance of IOLs. Beyond the average range, the anti-misalignment design narrowed the reductions of MTF50 from 23.18% to 8.60% for decentration and from 40.31% to 27.96% for tilt (P = .0010, two-factor analysis of variance). The optical performance varied in anti-misalignment IOLs with different diopters, types, and degrees of malpositions at different aperture sizes. In both photopic and mesopic conditions and all probable misalignments, from the perspective of MTF50, better sharpness generally may be achieved with the 8.00-D ZO optic designed lens and 17.00-D high-order optical aspheric surface designed lens. For 26.00-D IOLs with different misalignments, the ABC design was more resistant to decentrations, whereas the high-order optical aspheric surface design was more resistant to tilts. Aspheric monofocal IOLs with an anti-misalignment design can effectively resist decentration and tilt. Anti-misalignment IOLs for complicated cataract could be selected according to diopter of IOL and types and degrees of probable IOL malpositions. [J Refract Surg. 2023;39(7):446-455.].

To investigate influencing factors of glare in patients with myopia after small incision lenticule extraction (SMILE). Thirty patients (60 eyes) aged 24.9 ± 4.5 years with spherical equivalent of -6.69 ± 1.10 diopters (D) and astigmatism of -1.25 ± 0.76 D who underwent SMILE were consecutively recruited in this prospective study. Visual acuity, subjective refraction, Pentacam corneal topography (Oculus Optikgeräte GmbH), pupillometry, and glare test (Monpack One; Metrovision) were measured preoperatively and postoperatively. All patients were followed up for 6 months. The generalized estimation equation was used to judge the determinants of glare after SMILE, and a P value less than .05 was statistically significant. Under mesopic conditions, the halo radii preoperatively and at 1, 3, and 6 months after SMILE were 207.72 ± 46.67, 216.17 ± 40.63, 200.67 ± 34.68, and 193.50 ± 40.75 minutes of arc (arcmin), respectively. Under photopic conditions, the glare radii were 79.10 ± 17.78, 87.00 ± 20.44, 78.00 ± 14.59, and 72.00 ± 15.27 arcmin, respectively. Compared with preoperative glare, no significant changes were detected in postoperative glare. However, glare at 6 months was statistically significantly improved compared to the values at 1 month (both P < .05). Under mesopic conditions, the main influencing factors of glare were sphere (P = .007), astigmatism (P = .032), uncorrected distance visual acuity (UDVA) (P < .001), and postoperative time (all P < .05). Under photopic conditions, the main influencing factors of glare were astigmatism, UDVA, and postoperative time (all P < .05). Glare improved with time during the early stages after SMILE for myopia. Less glare was found to be associated with better UDVA, and greater residual astigmatism and sphere translated to more obvious glare. [J Refract Surg. 2023;39(6):398-404.].