Clinical ophthalmology (Auckland, N.Z.)最新文献

Pseudoaccommodation is a critical yet often underappreciated factor influencing visual outcomes after cataract surgery. Despite the irreversible loss of true accommodation due to presbyopia or intraocular lens (IOL) implantation, many patients retain meaningful near and intermediate vision-a phenomenon driven by optical and anatomical contributors such as pupil size, astigmatism, and higher-order aberrations. This functional benefit, known as pseudoaccommodation, can be further enhanced pharmacologically through miotic agents like pilocarpine or surgically via multifocal and extended depth-of-field (EDOF) IOLs. However, these strategies may come with trade-offs, including dysphotopsia and reduced contrast sensitivity. Understanding the mechanisms and limitations of pseudoaccommodation is essential for optimizing IOL selection, managing patient expectations, and improving satisfaction. This comprehensive review synthesizes the current evidence on the anatomical, optical, pharmacologic, and technological factors that contribute to pseudoaccommodation, offering practical guidance for counseling both phakic and pseudophakic presbyopic patients.

Purpose: To quantify the clinical tolerance to induced with-the-rule (WTR, 90°) and against-the-rule (ATR, 0°/180°) astigmatism after implantation of an extended depth-of-focus (EDOF) intraocular lens (IOL), and to identify axis-specific trade-offs across the defocus curve.

Methods: In this non-randomized, comparative, cross-sectional study, nine pseudophakic patients (nine dominant eyes) implanted with a Tecnis Symfony^® EDOF IOL underwent monocular photopic testing (85 cd/m²) at 4 m using Early Treatment Diabetic Retinopathy Study (ETDRS) charts. Defocus curves were acquired from -5.00 D to +2.50 D in 0.50-D steps over best subjective refraction. Regular myopic astigmatism was optically induced with +1.00 D, +2.00 D, and +3.00 D positive cylindrical lenses at canonical axes (0°, 45°, 90°, 135°); analyses focused on WTR (90°) and ATR (0°/180°). Visual acuity (VA) was converted to logMAR. Repeated-measures ANOVA with Tukey post hoc testing assessed effects of cylinder magnitude, axis, and vergence (α=0.05).

Results: Distance VA remained functionally preserved with +1.00 D, while +2.00 D produced clinically meaningful deterioration and +3.00 D caused broad loss of acuity across vergences. Axis orientation modulated performance: WTR preserved distance acuity around plano, whereas ATR relatively favored intermediate and very near vergences (approximately -2.00 D to -3.50 D). ANOVA confirmed significant effects of cylinder magnitude and vergence (both p<0.01) and a significant axis-by-vergence interaction near plano and +0.50 D (p<0.05). These findings support a practical tolerance envelope of about +1.00 D for EDOF recipients, beyond which functional penalties become evident.

Conclusion: After EDOF implantation, regular astigmatism of ~+1.00 D is generally tolerated, while +2.00 D and +3.00 D compromise function across the defocus curve. Axis matters: WTR preferentially preserves distance VA and ATR relatively supports intermediate/near performance. These data provide actionable thresholds and axis-aware guidance for toric planning, residual-targeting, and patient counseling.

Background: Preoperative suboptimal correction (under/over-correction) is prevalent among myopic SMILE candidates. Existing studies lack data on its impact on early visual recovery and binocular function. This study aims to investigate the impact of preoperative suboptimal correction on early visual recovery in myopes undergoing SMILE and to compare these outcomes to normal values.

Methods: Visual results of 148 eyes with preoperative suboptimal correction were compared with 72 full-corrected eyes after SMILE. Assessments included uncorrected distance visual acuity (UDVA), refraction, visual quality parameters (strehl ratio (SR), the modulation transfer function (MTF) curves), and binocular visual function (perceptual eye position, vergence-divergence dynamic and stereovision) at baseline and 1 week, 1 month and 3 months postoperatively.

Results: UDVA improved significantly faster in the full-correction group (1-week follow-up) versus the suboptimal group (1-month follow-up). The full-correction group exhibited superior SR (P = 0.02) and MTF performance at 4-mm pupil (P < 0.05 at 5 and 10 cycles/degree) at 1 month. Horizontal perceptual deviation transiently increased at 1 month but normalized by 3 months in the suboptimal group. Convergence function decreased at 1 month but returned to baseline at 3 months in the suboptimal correction group, while improved at both 1-month and 3-month visits in the full-correction group. Divergence function improved in both groups with no intergroup differences (all P > 0.05).

Conclusion: Myopic subjects with preoperative suboptimal correction exhibit delayed visual recovery (notably UDVA and binocular function) compared to fully corrected peers after SMILE. These findings confirm SMILE's safety and efficacy even in eyes with suboptimal presenting visual acuity (PVA), while indicating the need for preoperative counseling to align patient expectations and targeted postoperative visual training to accelerate recovery-strategies that may enhance patient satisfaction.

Purpose: To investigate the effects of orthokeratology (ortho-K) lens decentration on ocular and biomechanical parameters and analyze the correlation of these parameters with decentration distance.

Methods: Thirty eyes of 30 myopic adult subjects, mean age 28.2 years who had worn ortho-K lens for two hours were recruited for this prospective study. Under both the central and eccentric lens fitting conditions, the subjects underwent two rounds of assessments with a week-long interval. The ocular parameters were measured by an IOL Master, whereas the biomechanical parameters were measured by a Corves ST. Differences between measurements were evaluated by one-way ANOVA and a post hoc test. Repeatability was analyzed based on within-subject standard deviation (Sw), repeatability coefficient (RC), intraclass correlation coefficient (ICC), and correlation of variation (CoV). Pearson correlation analysis was employed for correlation analysis.

Results: The ocular parameters showed no significant differences, whereas among the biomechanical parameters, the biomechanical corrected intraocular pressure (bIOP) (95% CI 15.8-16.7 mmHg, 14.7-15.6 mmHg, 14.5-15.5 mmHg for baseline, central and eccentric group) and stiffness parameter at first applanation (SPA1) (95% CI 111.7-122.4, 102.3-113.0, 103.9-115.1 for baseline, central and eccentric group) showed significant changes after ortho-K. In all groups, the ocular parameters showed good repeatability with ICC values greater than 0.95 and CoV values lower than 1.3%. By contrast, the biomechanical parameters showed poor repeatability with low ICC values (ie, below 0.7) for the length of flattened cornea at the first and second applanations (A1L and A2L, respectively) and for velocity of corneal apex at the second applanation (A2V) in the baseline group; for A1L, A2L, and bIOP in the central group; and for A1L and A2V in the eccentric group. The correlation analysis showed the positive relationship in A2L between central and eccentric groups.

Conclusion: Ortho-K lens decentration did not influence the ocular parameters. However, the biomechanical parameters, the bIOP and SPA1 related to corneal thickness changed after ortho-K.

The popularity of refractive surgery has grown significantly in recent years, yet concerns about its effects on glaucoma evaluation and progression remain unclear. Various techniques in both corneal and lens-based refractive surgery have been developed, necessitating different strategies for monitoring glaucoma. With the advent of advanced technologies and instruments, our ability to detect and monitor glaucoma in patients undergoing refractive surgery has improved. This review provides comprehensive information on glaucoma risk assessment and monitoring from preoperative to postoperative stages for different types of refractive surgery, highlighting key considerations at each stage of care. We aim to raise awareness and confidence among refractive surgeons handling cases involving glaucoma suspects or patients with glaucoma at any stage of refractive surgery. Based on updated evidence, we provide key recommendations that include conducting a comprehensive glaucoma risk assessment, ensuring vigilant monitoring of high-risk cases, and selecting the most suitable tonometer for precise intraocular pressure measurement.

Paediatricians are often the first to identify children with DS and their awareness on associated ocular comorbidities, play a critical role in ensuring timely referral to general ophthalmologists for diagnosis and management. Among these, keratoconus (KC) has a significantly higher prevalence among Down syndrome (DS) compared to the general population. The awareness and understanding of KC, is essential for preventing vision loss. This review summarizes the current understanding of KC in DS, on epidemiology, pathophysiology, diagnostic challenges, and management. The children with DS, have thinner and steeper corneas since birth, complicates the diagnostic and management protocols. Poor cooperation of the children for imaging, compromised scan qualities, need for sedation and repeatability of scans poses diagnostic challenges. Early intervention with corneal cross-linking (CXL) is shown to be effective in halting disease progression. The surgical options in advanced cases, carry higher risks in DS patients due to factors such as eye rubbing, increased infection rates, and challenges in postoperative compliance. Managing KC in DS requires a comprehensive approach involving early referral by Paediatricians, pre-emptive diagnosis, and timely intervention with CXL to prevent disease progression. Future research should focus on preclinical gene prediction and developing standardized screening protocols for KC among DS to prevent vision loss and thereby improve quality of life among them.

Purpose: This study aimed to compare the visual outcomes, safety and efficacy of myopic keratorefractive lenticule extraction treatments using the newer Zeiss VisuMax 800 system over its precursor, the VisuMax 500 system.

Patients and methods: A retrospective review conducted at a private clinic in Western Australia of myopic keratorefractive lenticule extraction treatments with the VisuMax 500 and the VisuMax 800 systems between July 2021 and February 2023. Pre-operative and 1-month post-operative data were compared between the two cohorts. Demographics, best corrected visual acuity, uncorrected distance visual acuity, mean refractive spherical equivalent, total suction time and complications were recorded.

Results: Fifty procedures for each system were identified. Eight eyes in the VisuMax 500 cohort (group 1) and five eyes in the VisuMax 800 cohort (group 2) were excluded due to non-attendance at the 1-month post-operative review. The average total suction time was 34 seconds vs 13 seconds respectively. A single case of suction loss occurred in group 1. The mean pre-operative mean refractive spherical equivalent of groups 1 and 2 were -6.02D (-3.63 to -9.00) and -5.56D (-2.75 to -8.88) (P = 0.20). The mean post-operative mean refractive spherical equivalent of the two groups were 0.08D (-1.00 to 1.25) and -0.03D (-2.25 to 1.00) (P = 0.31).

Conclusion: The VisuMax 500 and 800 systems have similar visual outcomes and no significant difference in safety profiles. The main advantage of the newer VisuMax 800 femtosecond laser is its speed and potential for less cases of suction loss. Larger studies over longer terms are required.

Purpose: To study the association between fundus changes and visual prognosis in central retinal artery occlusion (CRAO).

Methods: A total of 222 CRAO cases hospitalized at Hebei Eye Hospital between January 2013 and December 2016 were included in this study. Fundus photographs on admission were evaluated via dual independent image review. Retinal ischemic edema and cilioretinal arteries were graded. Logistic regression analysis was performed to explore the association between fundus findings and visual prognosis in CRAO.

Results: The main fundus changes in CRAO patients on admission included retinal ischemic edema (95.0%), cherry-red spot (89.6%), retinal arterial narrowing (65.3%) and venous narrowing (53.6%), cotton-wool spots (53.6%), optic disc margin blurring (36.0%) and pallor (35.1%), retinal venous dilation (21.2%), and retinal hemorrhages (12.6%). Upon admission, retinal edema grades were grade 0 in 11 eyes (5.0%), grade 1 in 23 (10.4%), grade 2 in 80 (36.0%); and grade 3 in 108 (48.6%). Forty-seven eyes (21.1%) showed fissure-like edema, while 164 eyes (73.9%) exhibited a diffuse pattern. Chi square test showed the grade and pattern of retinal ischemic edema, the border and size of the cherry-red spot, the presence of retinal hemorrhage and cotton wool spots, macular folds and retinal arterial narrowing were all significantly associated with the time from symptom onset to presentation. Multivariate logistic regression analysis identified visual acuity at presentation, retinal ischemic grade, optic disc margin clarity, cherry-red spot size, and the presence of a cilioretinal artery supplying the macula as predictive factors for visual prognosis in CRAO.

Conclusion: The fundus changes in acute CRAO were correlated with the visual prognosis. Visual acuity at presentation, grade of retinal ischemic edema, clarity of the optic disc margin, size of the cherry-red spot, and the presence of a cilioretinal artery supplying the macula could be predictive factors for visual prognosis in CRAO.