Objective Visual Quality Research Articles

Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile.

The study aims to evaluate visual acuity and objective visual quality before and after the monocular bi-aspheric ablation profile for correction of presbyopia surgery. This prospective self-control study included 20 cases and 38 eyes of patients who underwent monocular bi-aspheric ablation profile correction of myopia with presbyopia at the Eye Hospital of Shandong University of Traditional Chinese Medicine from January 2023 to January 2024. These patients were selected for observation, and each patient's preoperative and postoperative uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), spherical aberration (SA) (within 6 mm), horizontal and vertical coma (within 6 mm), and corneal aspheric index (Q-value) (within 6 mm) were evaluated. Statistical data analysis was performed at different time points before and after the operation. There were statistically significant differences in UDVA between dominant and non-dominant eyes before and after surgery (Z = -3.784, p < 0.001; Z = -3.817, p < 0.001). Post-operatively, 90% of the non-dominant eyes achieved UNVA of J1 and above, and 95% of the bilateral eyes achieved UNVA of J1 and above. Significant differences were found in the SA of the dominant eyes, which showed a positive increase (Z= -3.784, p < 0.001); however, compared with the dominant eye, the SA of the non-dominant eye was negatively increased, but the difference was not statistically significant (p = 0.08). There was a significant difference in the vertical coma of the dominant eye before and after the operation, but there was no significant difference in non-dominant eyes. There was no significant difference in the change of binocular horizontal coma before and after the operation. There were significant changes in the Q value of both eyes before and after the operation (Z = -3.923, p < 0.001; Z = -3.51, p < 0.001). After the monocular bi-aspheric ablation profile, the cornea of the non-dominant eye showed a prolate shape, negative SA increased, and the UDVA and UNVA improved after the operation.

Comparison of objective visual quality between SMILE and FS-LASIK in moderate-to-high myopia.

This study aims to compare the changes in the corneal wavefront aberrations and the objective visual quality resulting from two types of eye surgery-small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK)-in patients with moderate-to-high myopia. A prospective analysis was performed on 98 eyes of 51 patients who underwent SMILE. Additionally, 88 eyes of 45 patients who underwent FS-LASIK were analyzed. All patients underwent ocular examination preoperatively and at 1 day, 1 week, 1 month, and 3 months postoperatively. Corneal aberrations and objective visual quality were measured using the Optical Quality Analysis System II (OQAS II) and Optical Path Difference Scan III (OPD-Scan III). At postoperative 1 day and 1 week, there was a statistically significant difference in uncorrected distance visual acuity (UDVA) between SMILE and FS-LASIK (P < 0.05). Postoperative spherical (S), cylinder (C) and spherical equivalent refraction (SE) were similar between the two groups (P > 0.05). In both groups, the absolute magnitude of total higher-aberrations (tHOA), piston, vertical tilt, vertical coma, and spherical aberration (SA) increased after surgery compared to preoperative values (P < 0.05). There was no significant difference in Δhorizontal tHOA, Δhorizontal tilt, Δhorizontal coma, and Δhorizontal trefoil between the two groups (P > 0.05), and the FS-LASIK had higher Δvertical trefoil and ΔSA (P < 0.05) but lower Δpiston, Δvertical tilt, and Δvertical coma than the SMILE group (P < 0.05). There was a rise in objective scattering index (OSI) and a decline in both modulation transfer function (MTF) cutoff and Strehl ratio (SR) after surgery compared to preoperative values in both groups (P < 0.05). There was a statistically significant difference in the OSI at 1 day and 3 months between the two groups (P < 0.05). Postoperative MTF cutoff and SR were similar between the two groups (P > 0.05). Postoperative OSI was positively correlated with corneal tHOA (0.261 ≤ R ≤ 0.483, P < 0.05) and was negatively correlated with vertical tilt and vertical coma (-0.315 ≤ R ≤ -0.209, P < 0.05) in both groups. While both SMILE and FS-LASIK can effectively correct moderate-to-high myopia, there is an increase in corneal aberrations and a postoperative delay in objective visual quality. The cornea may require a longer recovery period in the SMILE. OPD-Scan III combined with OQAS II is a useful supplementary inspection for assessing the optical quality following refractive surgery.

Clinical efficacy evaluation of the implantation of a diffractive trifocal intraocular lens in high myopia eyes: Two-year follow-up.

To evaluate the long-term subjective and objective visual quality after implantation of a diffractive trifocal intraocular lens (IOL) in high myopic eyes. A total of 53 eyes from 38 patients with high myopia who underwent phacoemulsification and trifocal IOL implantation were investigated. The visual acuity, contrast sensitivity, diopter, defocus curve, and objective visual quality at 1 month, 3 months, 1 year, and 2 years after surgery, as well as the satisfaction questionnaire and VF-14 scale, were statistically analyzed. The average age was 53.14 ± 4.70 years. The average preoperative spherical equivalent was -10.77 ± 3.98 D. Two years after surgery, 94.3% of the patients achieved an uncorrected distance visual acuity of 0.1 (LogMAR), and 84.9% and 94.3% of the patients had SE within ±0.50 D and ±1.0 D, respectively. The defocus curve was smooth and at a high value within the range of 0 D to -2.50 D. In CS or objective visual quality, there was no significant difference at 3 months, 1 year, and 2 years after operation (all P > 0.05). The rate of spectacle independence was 100%. The proportion of patients with moderate or severe glare and halo was 10.5% and 13.2%, respectively. Furthermore, 23.7%, 26.3%, and 18.4% of the patients had difficulties in reading small font, doing delicate tasks, and driving or riding at night, respectively. The diffractive trifocal IOL implantation provided good distance, intermediate, and near uncorrected visual acuity for patients with cataracts and high myopia. It was safe, effective, predictable, and stable. It provided long-term good visual quality after surgery, with high spectacle independence and high patient satisfaction.

Efficacy of orthokeratology lens with the modified small treatment zone on myopia progression and visual quality: a randomized clinical trial

BackgroundTo evaluate the long-term effectiveness of orthokeratology (ortho-K) lenses with small treatment zone (STZ) or conventional treatment zone (CTZ) in controlling axial elongation in children with myopia as well as the impact on visual quality. We also sought to determine the effect of retinal visual signal quality on axial elongation.MethodsThis is a prospective randomized controlled study. A total of 140 participants (age ranging from 8 to 12 years) were randomly assigned to wear either STZ or CTZ ortho-K lenses. STZ ortho-K lenses design was achieved by changing the depth of reverse zone and the sagitta height of the optical zone. Using the IOL-Master 500, axial length (AL) was measured at baseline and after 6, 12 and 18 months of ortho-K treatment. Spherical aberration (SA) and corneal topographic parameters were obtained by the Pentacam anterior segment analyzer at baseline and the 1-month follow-up visit, and optical qualities were assessed by optical quality analysis system-II (OQAS-II) at baseline and after 1 month of lens wearing. Optical quality parameters mainly included the modulation transfer function (MTF) cutoff, Strehl ratio (SR), objective scattering index (OSI), and predicted visual acuity (PVA).ResultsA total of 131 participants completed the study, including 68 in the STZ group and 63 in the CTZ group. The STZ group had significantly reduced AL elongation compared to the CTZ group after treatment (12 months: 0.07 ± 0.11 mm vs. 0.14 ± 0.12 mm, P = 0.002; 18 months: 0.17 ± 0.15 mm vs. 0.26 ± 0.16 mm, P = 0.002). The topography in the STZ group showed a smaller treatment zone (TZ) diameter (2.50 ± 0.23 mm vs. 2.77 ± 0.18 mm, P < 0.001), a wider defocus ring width (2.45 ± 0.28 mm vs. 2.30 ± 0.30 mm, P = 0.006), and larger values of total amount of defocus (119.38 ± 63.71 D·mm2 vs. 91.40 ± 40.83 D·mm2, P = 0.003) and total SA (0.37 ± 0.25 μm vs. 0.25 ± 0.29 μm, P = 0.015), compared with the CTZ group. Objective visual quality decreased in both groups (P < 0.001). This was evidenced by a greater decrease in MTF cutoff (− 14.24 ± 10.48 vs. − 10.74 ± 9.46, P = 0.047) and SR values (− 0.09 ± 0.07 vs. − 0.06 ± 0.07, P = 0.026), and an increase in OSI value (0.84 ± 0.72 vs. 0.58 ± 0.53, P = 0.019). PVA9% decreased significantly in the STZ group but not the CTZ group. A statistically significant negative correlation was found between the changes in total SA and MTF cutoff values (r = − 0.202, P = 0.025). AL changes were associated with sex, change of MTF cutoff value, increment of total SA and TZ area.ConclusionsCompared with CTZ ortho-K lenses, STZ ortho-K lenses significantly inhibited axial elongation in children with myopia while moderately reducing their objective visual quality. Axial elongation was affected by retinal visual quality, and it may be a possible mechanism for ortho-K slowing myopia progression.Trial registration This trial is registered at Chinese Clinical Trial Registry on November 5, 2019 with trial registration number: ChiCTR1900027218. https://www.chictr.org.cn/showproj.html?proj=45380

Evaluation of visual quality and refractive outcomes of myopia with presbyopia after laser blended vision surgery

Objective: To investigate the postoperative outcomes and visual quality following laser blended vision (LBV) surgery for the correction of myopia with presbyopia. Methods: This is a prospective study. A total of 50 patients (100 eyes) who underwent LBV surgery for myopia with presbyopia at Beijing Tongren Hospital, Capital Medical University, between August 2021 and March 2022 were included. Uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), best-corrected distance visual acuity (BCDVA), manifest refraction spherical equivalent (MRSE) were measured preoperatively and at 1, 3, 6, 12, and 24 months postoperatively for the dominant eye, non-dominant eye, and both eyes. Effectiveness Index (EI) and Safety Index (SI) were calculated to evaluate refractive outcomes. Accommodation function and contrast sensitivity were assessed to evaluate functional vision. Objective visual quality was assessed using higher-order aberrations (HOAs) and a dual-channel visual quality analysis system. Subjective visual quality was evaluated using a questionnaire. Results: At 24 months postoperatively, the EI and SI for the dominant eye were 1.04±0.23 and 1.14±0.14, respectively, while for the non-dominant eye, they were 0.85±0.21 and 1.06±0.08, respectively. Although there were statistically significant differences in UNVA between the eyes at 1 and 3 months postoperatively (all P<0.05), no significant differences were observed from 6 months onward (all P>0.05). At 6 months postoperatively, the UNVA for the dominant and non-dominant eyes were 0.07±0.13 and 0.03±0.13, respectively, with no significant difference (P>0.05). MRSE showed no significant differences at any follow-up time points up to 24 months. Accommodation function did not decrease compared to preoperative levels at any postoperative follow-up. Increases in HOAs were primarily due to spherical aberrations, and there were no significant differences in objective visual quality before and after surgery. Contrast sensitivity improved significantly at 24 months postoperatively compared to preoperative levels. At 24 months postoperatively, 11 out of 12 patients reported good visual quality in the questionnaire. Conclusions: LBV surgery gradually achieves good binocular blended vision within 6 months postoperatively and demonstrates good safety, efficacy, and stability at 24 months. It maintains good functional vision and visual quality with high postoperative patient satisfaction.

Comparison of long-term visual quality after keratorefractive lenticule extraction and implantable collamer lens V4c for high myopia.

To compare the long-term refractive outcomes and visual quality after KLEx and EVO-ICL implantation for high myopia. Eye & ENT Hospital of Fudan University, Shanghai, China. A retrospective study. This study included 31 KLEx-treated patients (31 eyes, spherical equivalent: -7.62D ± 1.22) and 32 ICL-treated patients (32 eyes, spherical equivalent: -8.22D ± 1.18). Refractive outcomes and objective visual quality were examined. Subjective visual quality was evaluated by a customized questionnaire. Patients' satisfaction was graded. Five-year postoperatively, the efficacy (KLEx: 0.96 ± 0.20; ICL: 1.03 ± 0.20; P = 0.164) and safety indices (KLEx:1.12 ± 0.20; ICL: 1.21 ± 0.19; P = 0.067) were comparable. Statistically higher proportions of ICL-treated eyes achieved a postoperative UDVA of 20/20 or better (P = 0.035). Refractive predictability was similar between the two groups (P = 0.947), whereas more KLEx-treated eyes had myopic refractive errors (P < 0.001). Total coma was significantly higher after KLEx (P = 0.020), and greater total trefoil was observed after ICL implantation (P = 0.006). Haloes were the primary visual disturbance in both groups (KLEx: 64.5%; ICL: 93.8%). The incidences of haloes (P < 0.001), glare (P = 0.004), and starbursts (P = 0.043) were notably higher after ICL implantation. The patient's satisfaction scores were similar (KLEx: 9.10 ± 1.27; ICL: 9.10 ± 1.27; P = 0.894). For high myopia, EVO-ICL yielded better long-term refractive outcomes than KLEx. Haloes were the chief complaint in both groups, with a significantly higher incidence after ICL implantation.

Comparison of Objective Visual Quality Following SMILE and SmartPulse Technology-Assisted TransPRK at a 1,050-Hz Ablation Frequency for Moderate-to-High Myopia.

To compare the objective visual quality of moderate-to-high myopia corrected by small incision lenticule extraction (SMILE) and transepithelial photorefractive keratectomy (TransPRK) at a 1,050-Hz ablation frequency, assisted by Smart-Pulse technology (SCHWIND eye-tech-solutions). This study involved 123 patients (123 eyes) with moderate-to-high myopia between July 2020 and January 2021. They were categorized into the SMILE group (67 patients, 67 eyes) and the TransPRK group (56 patients, 56 eyes). Follow-ups were conducted at 6 months postoperatively to record the logarithm of the minimum angle of resolution visual acuity, and the Strehl ratio and higher order aberrations were measured using the Sirius anterior segment analysis device (SCHWIND eye-tech-solutions) under a 6-mm pupil diameter at various postoperative intervals. At 1 week and 1 month postoperatively, the uncorrected distance visual acuity (UDVA) in the SMILE group was superior to that in the TransPRK group (P < .05 for both). At 1 week and 1 month postoperatively, the Strehl ratio value in the SMILE group was higher than that in the TransPRK group (P < .05 for both). At 1, 3, and 6 months postoperatively, coma was greater in the SMILE group than in the TransPRK group (P < .05 for all). Spherical aberrations were lower in the SMILE group than in the TransPRK group at 3 and 6 months postoperatively (P < .05). At 6 months postoperatively, UDVA was -0.09 ± 0.08 and -0.11 ± 0.05 logMAR in the SMILE and TransPRK groups, respectively, which exceeded their preoperative corrected distance visual acuity of -0.05 ± 0.04 and -0.09 ± 0.08 logMAR (all P < .001). Compared with preoperative values, the Strehl ratio, total higher order, coma, and spherical aberration differences were significantly increased postoperatively in both groups (all P < .001). Both surgical methods improved UDVA and each had its advantages. The visual quality of SMILE was superior at 1 week and 1 month postoperatively (Strehl ratio values were higher than those of the TransPRK group), and its spherical aberration was lower than that of the TransPRK group at 3 and 6 months; TransPRK with SmartPulse technology with a 1,050-Hz ablation frequency showed that coma was significantly lower than that of the SMILE group at 1, 3, and 6 months postoperatively. [J Refract Surg. 2024;40(7):e490-e498.].

Effect of low-degree astigmatism on the objective visual quality.

To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System (OQAS). This study enrolled 46 participants (aged 23 to 30y, 90 eyes) with normal or corrected-to-normal vision. The cylindrical lenses (0, 0.5, 0.75, 1.0, and 1.25 D) were placed at the axial direction (180°, 45°, 90°, and 135°) in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism. OQAS was used to detect the objective visual quality, recorded as the objective scattering index (OSI), OQAS values at contrasts of 100%, 20%, and 9% predictive visual acuity (OV100%, OV20%, and OV9%), modulation transfer function cut-off (MTFcut-off) and Strehl ratio (SR). The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters. Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed. The increase of OSI per degree of astigmatism at 180°, 45°, 90°, and 135° axis were 0.38 (95%CI: 0.35, 0.42), 0.50 (95%CI: 0.46, 0.53), 0.49 (95%CI: 0.45, 0.54) and 0.37 (95%CI: 0.34, 0.41), respectively. The decrease of MTFcut-off per degree of astigmatism at 180°, 45°, 90°, and 135° axis were -10.30 (95%CI: -11.43, -9.16), -12.73 (95%CI: -13.62, -11.86), -12.75 (95%CI: -13.79, -11.70), and -9.97 (95%CI: -10.92, -9.03), respectively. At the same astigmatism degree, OSI at 45° and 90° axis were higher than that at 0° and 135° axis, while MTFcut-off were lower. Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

The Impact of Back Optic Zone Design in Orthokeratology on Visual Performance.

To evaluate the visual performance in adolescents undergoing orthokeratology (OrthoK) treatment with two different optical zone diameters (OZDs). This randomized, double-masked, self-controlled prospective study was conducted at Tianjin Eye Hospital (Tianjin, China) in June 2022. Thirty-six eligible schoolchildren were enrolled and fitted with corneal refractive therapy lenses with two sizes of OZDs (5 mm [5OZ] and 6 mm [6OZ]). Each participant was randomized to wear the 5OZ in one eye and the 6OZ in the contralateral eye. Subjective visual quality was assessed using visual acuity, refraction, contrast sensitivity function, and visual symptoms, and the objective optical quality was assessed using ocular higher order aberrations (HOAs) and modulation transfer function (MTF). Thirty-five myopic children completed a 1-month follow-up visit. The 5OZ lens induced significantly smaller treatment zone diameters than the 6OZ lens (P < 0.001). Subjective visual quality did not differ significantly between the two groups. Compared to baseline, aberrations of Z40, coma-like, spherical-like, and total HOAs in both groups increased significantly (P < 0.05). For the 3-mm pupils, spherical aberration in the 5OZ group was significantly higher than that in the 6OZ group (P < 0.05). The MTF value of the 6OZ group was significantly higher than that of 5OZ group for 0.3 and 1.5 cycles per degree for the 3-mm pupils (P = 0.006 and P = 0.026, respectively). However, HOAs or MTF did not differ significantly between the two groups for the 5-mm pupils. The difference induced by varying OZD was significant only in the smaller pupil condition. The selection of OZD in OrthoK designs in real-world patient management should be done while considering individual pupil size. This study revealed that the objective visual quality of small OZD lenses was only slightly affected for the small pupil size.

Effectiveness of toric intraocular lens implantation for correcting irregular corneal astigmatism in cataract eyes

A retrospective cohort study was conducted to observe the correction effect of Toric intraocular lens (IOL) implantation in cataract eyes with specific types of irregular corneal astigmatism. Thirty-four eyes with either the "asymmetric bow-tie" pattern (Type I) or the "angled bow-tie" pattern (Type II) were included. Corneal topography was assessed using Pentacam HR, and changes in preoperative corneal astigmatism, visual acuity, manifest refraction, and objective visual quality were measured and compared. The average uncorrected distance visual acuity improved significantly from 0.86 ± 0.40 logMAR to 0.22 ± 0.15 logMAR (P < 0.001). Preoperative corneal astigmatism of 2.05 ± 0.90 D was corrected to a postoperative residual astigmatism of 0.78 ± 0.57 D (P < 0.001), with 32% of eyes within 0.50 D. The residual astigmatism prediction errors in Type I and Type II cases were (0.97 ± 0.68 D) and (0.66 ± 0.37 D), respectively (P = 0.100). The mean spherical equivalent prediction error in Type II cases (0.07 ± 0.36 D) was significantly smaller than that in Type I cases (− 0.29 ± 0.52 D) (P = 0.030). This study concludes that Toric IOL implantation effectively corrects specific types of irregular corneal astigmatism in cataract surgery. Eyes with the "angled bow-tie" pattern show higher accuracy in refractive predictions compared to eyes with the "asymmetric bow-tie" pattern.

Comparative visual outcomes of the first versus second eye following small-incision lenticule extraction (SMILE)

BackgroundThis study aimed to compare the visual outcomes of the first operated eyes with those of the second operated eyes following small-incision lenticule extraction (SMILE).MethodsA total of 202 patients (404 eyes) underwent SMILE using the tear film mark centration method for myopia and myopic astigmatism correction. Baseline characteristics, objective optical quality, decentered displacement, induced corneal aberrations, and modulation transfer function (MTF) values were assessed. Linear regression analyzed the relationship between decentration and visual quality parameters, including corneal aberrations and MTF values.ResultsNo significant difference was observed in objective visual quality, efficacy, and safety indexes between the two groups (all P > 0.05). The average decentered displacement for the first and second surgical eyes was 0.278 ± 0.17 mm and 0.315 ± 0.15 mm, respectively (P = 0.002). The horizontal coma in the first surgical eyes were notably lower than in the second (P = 0.000). MTF values at spatial frequencies of 5, 10, 15, and 20 cycles/degree (c/d) were higher in the first surgical eyes compared to the second (all P < 0.05). Linear regression indicated that high-order aberrations (HOAs), root mean square (RMS) coma, spherical aberration, horizontal coma, vertical coma, and eccentric displacement were all linearly correlated. Furthermore, MTF values exhibited a linear relationship with eccentric displacement across these spatial frequencies.ConclusionsThere was no discernible difference in visual acuity, efficacy, or safety between the two operated eyes. Nonetheless, the first operated eyes exhibited reduced decentered displacement and demonstrated superior outcomes in terms of horizontal coma and MTF values compared to the second operated eyes following SMILE. The variations in visual quality parameters were linearly correlated with decentered displacement.

Visual outcomes and patient satisfaction after implantations of three types of presbyopia-correcting intraocular lenses that have undergone corneal refractive surgery

This prospective, non-randomized, comparative study aimed to compare the visual outcomes and patient satisfaction after implantations of three presbyopia-correcting intraocular lenses (IOLs) after myopic refractive surgery. It was conducted from January 2020 to December 2021 in Shanghai Heping Eye Hospital. Patients were divided into three groups based on the type of IOL implanted. The visual acuity, refractive stability, high-order aberrations, objective visual quality, spectacle independence, and visual function index 14 questionnaire scores of the three groups were compared. This study included 78 eyes of 39 patients: 26 eyes with 839MP, 26 eyes with MF30, and 26 eyes with ZXR00. Uncorrected distance visual acuity improved significantly for all three groups. For a pupil diameter of 4.0 mm, the spherical aberrations of the three groups were 0.33 ± 0.16 μ, 0.50 ± 0.08 μ, and 0.39 ± 0.10 μ, respectively. The spectacle independence for distance vision was over 90% in each group; for near vision, it was only 25% for the ZXR00 group. All three types of presbyopia-correcting IOLs improved visual quality in post-LASIK or PRK patients. However, the high incidence of photic phenomena after presbyopia-correcting IOL implantation in patients who have undergone myopic LASIK should not be neglected.

Effectivity and safety of trifocal intraocular lenses and capsular tension rings implantation for cataract patients with axial high myopia.

To assess effectivity and safety of trifocal intraocular lenses (IOLs) and capsular tension rings in treating cataract patients with axial high myopia. A prospective nonrandomized controlled clinical trial was conducted. Totally 98 eyes (74 patients) who underwent femtosecond laser-assisted cataract surgery (FLACS) with trifocal IOLs were enrolled in the study and followed up for 2y after surgery: 46 eyes (33 patients) with capsular tension ring implantation in the long axial lengths (AL) group (26<AL<29 mm) and 52 eyes (41 patients) in the normal AL group (22<AL<24.5 mm). Postoperative outcomes about effectivity and safety, including the subjective and objective visual quality, and postoperative complications were assessed. Uncorrected distance visual acuity at 5 m and uncorrected intermediate visual acuity at 60 and 80 cm in the long AL group were significantly worse than those in the normal AL group at 3mo postoperatively (P<0.05). The differences in reading speed, spectacle independence and potential visual complaints between the two groups were not statistically significant (P>0.05). The dysfunctional lens index and total modulation transfer function (MTF) average height were similar between the two groups. The postoperative internal coma aberrations in the axial high myopia eyes were significantly higher than that in the normal AL group (P<0.05). The total satisfaction score in the long AL group (91.32±2.76) was slightly higher than that in the normal AL group (90.36±3.47), but there was no difference (P=0.136). A statistically negative correlation was found between corrected distance visual acuity (CDVA) and dysfunctional lens index (r=-0.382, P=0.009), and between CDVA and the total MTF average height (r=-0.374, P=0.01). But there was no significant correlation between CDVA and total satisfaction score (r=0.059, P=0.696). Postoperative complications mainly presented as posterior capsular opacity (PCO), retinal detachment and cystoid macular edema. There was no difference in the incidence of fundus disease (6.5% vs 3.8%, P=0.663) or PCO (17.4% vs 7.7%, P=0.217) between the two groups at two years. The utilization of trifocal IOL and capsular tension ring implantation is beneficial for cataract patients with axial high myopia undergoing FLACS. This approach not only ensures excellent subjective feelings and objective visual quality, but also does not increase the incidence of postoperative complications.

Tolerance to induced astigmatism of patients with trifocal or extended depth of focus intraocular lens implantation.

Residual astigmatism is common after cataract surgery involving implantation of an intraocular lens, yet the tolerance of presbyopia-correcting intraocular lens to astigmatism of different magnitudes and axes is poorly understood. Here we compared visual acuity and quality in the presence of induced astigmatism after implantation of a trifocal or extended-depth-of-focus (EDOF) intraocular lens, the two widely used presbyopia-correcting intraocular lenses. At least 3 months after implantation of a TFNT00 or ZXR00 intraocular lens, patients were analyzed by slit-lamp examination, non-contact tonometry, subjective refraction, iTrace aberrometry, and corneal topography. After correction of residual astigmatism, astigmatism of different magnitudes on different axes was induced using cylindrical lenses, and overall visual acuity was measured, while objective visual quality was measured using the Optical Quality Analysis System II. Subjects were also asked about subjective visual quality using the Visual Function-14 questionnaire. Comparison of 18 individuals who received a trifocal lens and 19 who received an EDOF lens showed that objective visual quality was better in the EDOF group regardless of the magnitude or axis of the induced astigmatism. In both groups, astigmatism of at least -1.00 DC influenced distant vision more severely when the axis was 45° than 0° or 90°, meanwhile astigmatism of at least -1.50 DC influenced near and intermediate vision more severely when the axis was 45° than 0° or 90°. Trifocal or EDOF intraocular lenses are less tolerant of oblique astigmatism than astigmatism with or against the rule. EDOF lenses may provide better objective visual quality than trifocal lenses in the presence of astigmatism, regardless of its magnitude or axis.

Analysis of visual quality improvement after implantation of PanOptix trifocal intraocular lens in cataract patients with different axial lengths.

To assess the visual quality, both subjective and objective, of cataract patients with varying axial lengths (AL) after PanOptix trifocal intraocular lens (IOL) implantation and investigated the lens tilt and its correlation with visual outcomes. From July 2020 to June 2022, 70 patients (140 eyes) diagnosed with age-related cataracts and undergoing PanOptix implantation at Chongqing Eye and Vision Care Hospital, Aier Eye Hospital Group, were included. Patients were assigned to either the observation group (35 cases, 70 eyes with PanOptix trifocal IOL) or the control group (35 cases, 70 eyes with bifocal IOL). Patients were further subdivided based on AL into AL < 24 mm (observation group: 23 eyes; control group: 26 eyes) and AL ≥ 24 mm (observation group: 47 eyes; control group: 44 eyes). Postoperative follow-up lasted three months. Visual acuity (distant, intermediate, near), objective visual quality (Strehl ratio: SR, total eye modulation transfer function (MTF)), and visual aberrations were measured preoperatively and at 3 months post-operation. Postoperatively, all groups saw significant improvements in uncorrected distance visual acuity (UCDVA), uncorrected intermediate visual acuity (UCIVA), and uncorrected near visual acuity (UCNVA) compared to preoperative values (T0) (all P < 0.05). Notably, UCIVA was significantly better in the observation group than in the control group (P < 0.05). At three months (T1), reductions in total high-order aberration (tHOA), internal high-order aberration (iHOA), coma, and trefoil aberrations were observed in both groups compared to baseline, with more significant decreases in the observation group (all P < 0.05). Both SR and MTF cutoff showed marked improvement from T0 to T1, with the observation group experiencing greater enhancements (both P < 0.05). The defocus curve of the observation group showed a gentle slope between +0.5 D and -3.0 D, maintaining superior visual acuity compared to the control group (P < 0.05). Subjective visual quality scores at T1 were significantly higher than at T0 for both groups (P < 0.05), with patients in the observation group scoring higher than those in the control group across all AL categories (P < 0.05). Spearman correlation analysis indicated that the tilt after PanOptix trifocal IOL implantation was associated with tHOA (r = 0.273, P = 0.022), iHOA (r = 0.433, P < 0.001), Trefoil (r = 0.360, P = 0.002) and coma (r = 0.688, P < 0.001). PanOptix trifocal IOL implantation in cataract patients across different AL significantly enhances visual quality compared to bifocal IOLs, suggesting a strong case for its clinical adoption.

A Dataset and Model for the Visual Quality Assessment of Inversely Tone-Mapped HDR Videos.

To enhance the viewer experience of standard dynamic range (SDR) video content on high dynamic range (HDR) displays, inverse tone mapping (ITM) is employed. Objective visual quality assessment (VQA) models are needed for effective evaluation of ITM algorithms. However, there is a lack of specialized VQA models for assessing the visual quality of inversely tone-mapped HDR videos (ITM-HDR-Videos). This paper addresses both an algorithmic and a dataset gap by introducing a novel SDR referenced HDR (SD-R-HD) VQA model tailored for ITM-HDR-Videos, along with the first public dataset specifically constructed for this purpose. The innovations of the SD-R-HD VQA model include 1) utilizing available SDR video as a reference signal, 2) extracting features that characterize standard ITM operations such as global mapping and local compensation, and 3) directly modeling interframe inconsistencies introduced by ITM operations. The newly created ITM-HDR-VQA dataset comprises 200 ITM-HDR-Videos annotated with mean opinion scores, gathered over 320 man-hours of psychovisual experiments. Experimental results demonstrate that the SD-R-HD VQA model significantly outperforms existing state-of-the-art VQA models.

Comparison of visual performance with iTrace analyzer following femtosecond laser-assisted cataract surgery with bilateral implantation of two different trifocal intraocular lenses.

To compare the postoperative binocular visual performance with an iTrace analyzer following femtosecond laser-assisted cataract surgery (FLACS) combined with bilateral implantation of two different types of diffractive trifocal intraocular lenses (IOL). During this retrospective observational study, patients who received bilateral FLACS combined with implantation of two different types of diffractive trifocal IOLs were evaluated. According to the IOLs' different types and design, the patients were divided into AT LISA tri839MP group (tri839 group) and AcrySof PanOptix TFNT00 group (TFNT group). Study parameters included preoperative and postoperative uncorrected distance visual acuity (UDVA) at 5 m, uncorrected near visual acuity (UNVA) at 30 cm and 40 cm, uncorrected intermediate visual acuity (UIVA) at 60 cm and 80 cm, postoperative refractive status, objective visual qualities and total high order aberrations (HOAs) postoperatively. The postoperative complications were also recorded. Totally 56 eyes of 28 patients (tri839 group, n=26; TFNT group, n=30) were included. Preoperative baseline characteristics between groups were not statistically significantly different. UDVA was not significantly different between groups except for 1wk follow-up due to the postoperative corneal edema. TFNT group showed statistically significant better UNIA at 60 cm than tri839 group at the 1wk (0.05±0.19 vs 0.15±0.10 logMAR, P=0.013), 1mo (0.05±0.12 vs 0.15±0.09 logMAR, P=0.001) and 3mo (0.04±0.12 vs 0.15±0.11 logMAR, P=0.001) follow-up, while tri839 group showed statistically significant better UNIA at 80 cm than TFNT group at the 1d (0.14±0.15 vs 0.20±0.14 logMAR, P=0.041) and 1mo (0.09±0.07 vs 0.14±0.10 logMAR, P=0.042) follow-up. Postoperative refractive status showed stable at every visit. Modulated transfer function (MTF) values and strehl ratio (SR) values were improved and HOAs were lower significantly after surgery. FLACS with bilateral implantations of both tri839 and TFNT00 can achieve satisfactory natural whole-course vision, high postoperative refractive stability and good visual quality but without significantly difference. iTrace aberration instrument can accurately evaluate the visual quality under different status.

The dynamic changes and influencing factors of visual symptoms after small incision lenticule extraction

BackgroundTo investigate the dynamic changes and influencing factors of visual symptoms after small incision lenticule extraction (SMILE).MethodsThis was a prospective observational study. Visual symptoms including glare, haloes, starbursts, hazy vision, fluctuation, blurred vision, double vision and focusing difficulties were evaluated before and 1, 3, 6 months after SMILE using a questionnaire. Generalized linear mixed models were used to assess the effects of preoperative characteristics and objective visual quality parameters on postoperative visual symptoms.Results73 patients/146 eyes were enrolled. Preoperatively, the most common symptoms were glare (55% of eyes), haloes (48%), starbursts (44%) and blurred vision (37%). At 1 month postoperatively, the incidence and extent scores of glare, haloes, hazy vision and fluctuation rose significantly. At 3 months, the incidence and extent scores of glare, haloes and hazy vision restored to baseline. And at 6 months, the extent scores of fluctuation returned to baseline. Other symptoms (e.g., starbursts) did not change before and 1, 3, 6 months after SMILE. Preoperative visual symptoms were associated with postoperative symptoms, as patients with a symptom preoperatively had higher postoperative scores for that symptom. Age was related to postoperative extent of double vision (coefficient = 0.12, P = 0.046). There were no significant associations between postoperative visual symptoms and preoperative SE, scotopic pupil size, angle kappa (with intraoperative adjustment), postoperative HOAs or scattering indexes.ConclusionsThe incidence and extent scores of hazy vision, glare, haloes and fluctuation increased at the first month after SMILE, and recovered to baseline at 3 or 6 months. Preoperative visual symptoms were associated with the postoperative symptoms and should be fully considered before SMILE.

A 3-month comparison study of subjective and objective visual quality of small incision lenticule extraction and transepithelial photorefractive keratectomy in patients with low and moderate myopia.

To compare the subjective and objective visual quality between small incision lenticule extraction (SMILE) and transepithelial photorefractive keratectomy (tPRK) in patients with low and moderate myopia. Patients undertaking SMILE or tPRK for the correction of low and moderate myopia were consecutively recruited in this prospective cohort study with a 3-month follow-up period. Objective evaluation [visual acuity test, manifest refraction, wavefront aberrations, the total cut-off value of the total modulation transfer function (MTFcut-off), and Strehl ratio (SR)] and subjective evaluation of visual quality (quality-of-life questionnaire) were conducted before surgery and at days 1, 7, 30, and 90 after surgery. A total of 47 patients (94 eyes) with SMILE and 22 patients (22 eyes) with tPRK were enrolled. The uncorrected visual acuity (UCVA) was better in SMILE patients on day 7 after surgery (1.13±0.13 vs 0.99±0.17, t=4.85, P<0.001) but was comparable at days 30 and 90. At day 90, the SMILE group had a lower spherical equivalent (SE) than the tPRK group (0.04±0.31 vs 0.19±0.43, t=2.08, P=0.042). Total higher order aberrations (HOAs) were induced in both surgical types, which were more evident in the tPRK group with 3-mm pupil diameter (0.16±0.07 vs 0.11±0.05, t=4.27, P<0.001) and 5-mm pupil diameter (0.39±0.17 vs 0.36±0.11, t=2.33, P=0.022). The MTFcut-off and SR showed a trend of improvement in both SMILE and tPRK patients but were statistically better in the SMILE group with both pupil diameters. There was a significant improvement of contrast sensitivity (CS) over baseline levels at the spatial frequency of 18 cycles/degree (c/d) in the SMILE group (F=2.72, P=0.033) and at 3 c/d (F=3.03, P=0.031), 12 c/d (F=3.72, P=0.013), and 18 c/d (F=4.62, P=0.004) in the tPRK group. The subjective quality of life questionnaire showed a steady improvement in the SMILE group (F=8.31, P<0.001) but not the tPRK group. SMILE and tPRK are both safe and effective ways to correct low and moderate myopia. A generally better and quicker recovery of visual quality favors the application of SMILE in qualified patients.

A survey on visual quality assessment methods for light fields

Unlike traditional cameras, Light Field (LF) cameras are able to capture both the intensity and direction of light rays from the scene. This rich information demands a certain amount of memory and bandwidth for storage and transmission, and to alleviate this requirement, LF content is processed and compressed. These operations often add degradations to the LF content that can affect its visual quality, requiring the use of methods that can measure visual quality as perceived by the end consumer. For this reason, the area of visual quality of immersive media has been gaining a lot of attention. This paper provides a comprehensive survey of state-of-the-art visual quality assessment methods for LF contents. First, we discuss the LF quality datasets that have been introduced, which contain subjective quality scores. Second, we discuss subjective quality assessment methods followed by objective quality assessment methods. Then we present a statistical comparison of a set of objective visual quality assessment methods. Finally, we summarize this survey and present future research demands for LF contents.