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

Purpose: Quantify clinical differences between standard and Correcting Applanation Tonometry Surface (CATS) Goldmann prism intraocular pressure (IOP) measurements in myopic laser in situ keratomileusis (LASIK) subjects and validate the CATS prism's accuracy using manometric comparisons in myopic LASIK cadaver eyes.

Design: Prospective cross-sectional cohort study and in vitro cohort comparison. One hundred ninety-eight eyes were enrolled from 100 subjects previously having undergone myopic LASIK. Separately, 18 enucleated globes that previously had undergone myopic LASIK were examined.

Methods: LASIK subjects were enrolled from 3 investigative sites, obtaining IOP measurements by Goldmann with standard and CATS prisms per international standard organization (ISO) standardized procedures. Intraocular pressure measurements were taken using 18 enucleated LASIK globes at the manometric pressures between 5 and 50 mmHg.

Outcome measures: Statistically demonstrate the CATS prism IOP measurement is higher and more accurate compared to intracameral pressure in LASIK-treated cadaver eyes than the standard prism. Clinical validation of higher (CATS) IOP measurements compared to the standard prism in live LASIK subjects.

Results: In vivo, the mean IOP difference (CATS minus standard) was +1.50 ± 2.13 mmHg (p<0.0001), indicating standard prism underestimation post-LASIK. In cadaver eyes, the CATS prism consistently measured closer to true intracameral pressure (5-50 mmHg, p<0.0001), with mean differences ranging from +1.2 to +1.8 mmHg. No difference in prism measurement variability were noted (p>0.05).

Discussion: The CATS prism yields higher, more accurate IOP readings than the standard prism in myopic LASIK patients, aligning closely with intracameral pressure. Prior cadaver and clinical studies confirmed equivalence of the two prisms in healthy corneas (non-LASIK). Clinically, the CATS prism enhances ocular hypertension detection in LASIK patients, potentially reducing undiagnosed glaucoma risk.

Conclusion: Findings may extend to other refractive surgeries or thin-cornea populations, warranting further study. Adoption of the CATS prism could refine postoperative IOP monitoring, impacting practice guidelines and patient outcomes.

Précis: Standard Goldmann tonometry underestimates intraocular pressure (IOP) after myopic LASIK, while a CATS prism improves accuracy, validated by intracameral pressure in LASIK cadaver eyes.

Purpose: To examine the influence of patient demographic characteristics and ophthalmic practice composition on access to cataract surgery in the United States as measured by preoperative best-corrected visual acuity (BCVA).

Patient and methods: This retrospective cohort study analyzed data from the IRIS^® Registry (Intelligent Research in Sight) for patients age >50 who had at least one BCVA measurement in the six months preceding cataract surgery performed between January 1, 2016, and December 31, 2020. We used mixed-effects models to estimate the relationship between individual-level demographic factors and practice-level composition factors and preoperative BCVA.

Results: A total of 2,387,045 individuals met the inclusion criteria. The mean BCVA prior to surgery was 0.23 (SD: 0.32) logMAR. The worst pre-operative BCVA was observed in patients with Hispanic race and ethnicity, while White patients had the best [0.34 (SD: 0.43), 0.21 (SD: 0.30); p<0.001]. Grouping patients in terms of percentage of BCVA worse than 20/50 prior to surgery, Hispanic patients, active smokers, and uninsured patients had higher percentages of worse preoperative vision (33.7%, 23.5%, 34.9%). Analysis of compositional effects of race and ethnicity, smoking, and insurance status showed that, regardless of an individual patient's demographic, patients treated at practices serving higher proportions of White patients showed better BCVA (b = -0.008 per 10 percentage points, P <0.001), while patients at practices with higher percentages of actively smoking patients showed worse BCVA (b=-0.016 per 10 percentage points active smoking patients, P <0.001). There was no compositional effect of insurance status.

Conclusions and relevance: Overall differences exist with regard to the visual acuity at which cataract surgery is initiated at both the level of the individual patient and the composition of the practice in which they are treated.

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.