Journal of refractive surgery最新文献

{"title":"Clinical Evaluation of the Stationary Scanning-Spot EX500 Excimer Laser System for Hyperopic LASIK in Patients With Hyperopia With and Without Astigmatism.","authors":"Karl Stonecipher, Jason Stahl, Michael Greenwood, Andrew Moyes, Paul Mann","doi":"10.3928/1081597X-20250520-04","DOIUrl":"10.3928/1081597X-20250520-04","url":null,"abstract":"<p><strong>Purpose: </strong>To collect additional safety and efficacy data in patients with and without astigmatism requiring hyperopic correction with planned bilateral laser in situ keratomileusis (LASIK) treatment using the WaveLight EX500 excimer laser (Alcon Laboratories, Inc).</p><p><strong>Methods: </strong>This was a prospective, single-arm, multicenter, interventional study of 60 eyes requiring refractive correction of hyperopia of +3.00 diopters (D) of sphere or less with or without astigmatism. Primary effectiveness endpoints were manifest refraction spherical equivalent (MRSE) within ±0.50 D at refractive stability (target > 50%) and within ±1.00 D at refractive stability (target > 75%). The primary safety endpoint was ocular adverse events.</p><p><strong>Results: </strong>With refractive stability established at 3 months postoperatively, MRSE within ±0.50 D of the intended target was achieved in more than 98% of eyes (> 96% at 12 months), manifest refraction sphere within ±0.50 D of target in 95% of eyes (> 98% at 12 months), and residual refractive cylinder of 0.50 D or less in 93% of eyes (100% at 12 months). No eyes had overcorrection or undercorrection of MRSE by greater than 1.00 D at refractive stability and subsequent time points. Postoperative manifest refraction sphere and residual manifest refraction cylinder were within ±1.00 D in 100% of eyes at 12 months. Safety and patient-reported findings were consistent with previous reports, with high safety profiles.</p><p><strong>Conclusions: </strong>The WaveLight EX500 excimer laser system was safe and effective for LASIK treatment of hyperopia with or without astigmatic refractive errors. <b>[<i>J Refract Surg</i>. 2025;41(7):e655-e661.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 7","pages":"e655-e661"},"PeriodicalIF":3.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing Plasma Formation and Minimizing Microcavitation to Enhance Clinical Outcomes in Keratorefractive Lenticule Extraction.","authors":"Soyoung Ryu, David S Y Kang, Kang Yoon Kim, Samuel Arba-Mosquera, Byunghoon Chung, Ikhyun Jun, Ahmed Elsheikh, Kyoung Yul Seo, Tae-Im Kim","doi":"10.3928/1081597X-20250509-05","DOIUrl":"https://doi.org/10.3928/1081597X-20250509-05","url":null,"abstract":"<p><strong>Purpose: </strong>To compare early postoperative visual outcomes and higher order aberrations (HOAs) between plasma and conventional keratorefractive lenticular extractions (P-KLEx and C-KLEx).</p><p><strong>Methods: </strong>In this retrospective case series, records of patients who underwent KLEx surgery using two protocols-C-KLEx (symmetric spot/track distance laser spacing, 100-nJ pulse energy, VisuMax 500; Carl Zeiss Meditec) or P-KLEx (asymmetric spot/track distance laser spacing, 85-nJ pulse energy, VisuMax 800; Carl Zeiss Meditec)-were reviewed. Both groups received an identical total energy dosage of 625 mJ/cm². Postoperative visual acuity and corneal higher order aberrations (HOAs) were analyzed at 1 day, 2 weeks, and 2 months.</p><p><strong>Results: </strong>Among 281 eyes, 136 and 145 were included in the C-KLEx and P-KLEx groups, respectively. At postoperative day 1, the mean uncorrected distance visual acuities (UDVAs) were 0.02 ± 0.04 and 0.01 ± 0.08 logarithm of the minimum angle of resolution (logMAR) in the C-KLEx and P-KLEx groups, respectively (<i>P</i> = .22); however, the P-KLEx group demonstrated significantly better mean UDVA at 2 weeks and 2 months postoperatively (both <i>P</i> < .05). At 2 weeks postoperatively, the mean UDVAs were -0.01 ± 0.04 and -0.04 ± 0.07 logMAR in the C-KLEx and P-KLEx groups, respectively, and at 2 months postoperatively, the mean UDVAs were -0.02 ± 0.04 and -0.04 ± 0.06 logMAR, respectively. The P-KLEx group showed less induction of total HOAs, coma, and spherical aberration than the C-KLEx group (all <i>P</i> < .05).</p><p><strong>Conclusions: </strong>P-KLEx, which minimizes microcavitation and creates a lenticule with near-pure plasma, shows more favorable outcomes than C-KLEx, yielding better early postoperative visual acuities and reduced induction of corneal HOAs. <b>[<i>J Refract Surg</i>. 2025;41(7):e635-e644.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 7","pages":"e635-e644"},"PeriodicalIF":2.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative Analysis of Posterior Staphyloma Using Foveal Angulation: Relationship to Leftover Astigmatism in Pseudophakic Eyes.","authors":"Richard Mackool, Li Wang, Maimunah Virk, Richard Mackool","doi":"10.3928/1081597X-20250520-01","DOIUrl":"https://doi.org/10.3928/1081597X-20250520-01","url":null,"abstract":"<p><strong>Purpose: </strong>To describe a method of measuring the amount of angulation of the foveal region of the macula in eyes with posterior staphyloma (PS) and then to determine whether or not those eyes manifest a refractive astigmatism as a result of the PS.</p><p><strong>Methods: </strong>Pseudophakic eyes with an axial length (AL) of 25 mm or greater were included in this retrospective study. Using vector analysis, \"leftover astigmatism\" (LOA) was calculated by subtracting total keratometric astigmatism (TKA) as measured with the IOLMaster 700 (Carl Zeiss Meditec AG) from the manifest refractive astigmatism (MRA) after vector subtraction of the astigmatic effect of a toric IOL, if present. The amount of LOA was analyzed to determine its relationship, if any, to the angulation of the fovea as measured by optical coherence tomography.</p><p><strong>Results: </strong>A total of 92 eyes of 58 patients (average age: 71.4 years) were enrolled. Eyes were separated into groups based on the degree of foveal angulation. No correlation was found (<i>P</i> > .05) between the amount of LOA and the degree of foveal angulation between all groups. There was no significant difference in LOA between the non-staphyloma (foveal angulation 10 degrees or less) and staphyloma (foveal angulation 11 degrees or greater) groups (<i>P</i> > .05), regardless of the amount of foveal angulation that was present.</p><p><strong>Conclusions: </strong>Foveal angulation can be used to objectively measure PS, a condition that does not contribute to refractive astigmatism. <b>[<i>J Refract Surg</i>. 2025;41(7):e667-e673.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 7","pages":"e667-e673"},"PeriodicalIF":2.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Transepithelial Corneal Cross-linking (CXL) Protocol Providing the Same Biomechanical Strengthening as Accelerated Epithelium-off CXL.","authors":"Nan-Ji Lu, Emilio A Torres-Netto, M Enes Aydemir, Sabine Kling, Nikki Hafezi, Léonard Kollros, Farhad Hafezi","doi":"10.3928/1081597X-20250515-09","DOIUrl":"https://doi.org/10.3928/1081597X-20250515-09","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the biomechanical strength of a new transepithelial corneal cross-linking (epi-on CXL) protocol without iontophoresis and additional oxygen, and to compare it to the most broadly used accelerated epithelium-off (epioff) CXL protocol.</p><p><strong>Methods: </strong>A total of 150 porcine eyes were assigned equally into three study groups: epi-on, epi-off, and control. For the epi-on and control groups, a penetration enhancer solution was applied to the corneal surface before soaking with 0.1% hypo-osmolar riboflavin without carrier. In the epi-off group, a manual abrasion was performed, followed by the application of the same 0.1% hypo-osmolar riboflavin solution. The epi-on and epi-off groups were irradiated at 365-nm ultraviolet-A (UV-A): in the epi-on group, 18 mW/cm² pulsed (1 second on-1 second off) UV-A was applied for 15 minutes (fluence 8.1 J/cm²) and in the epi-off group, 9 mW/cm² continuous UV-A for 10 minutes were used (fluence 5.4 J/cm²). Stress-strain extensiometry was performed to determine corneal biomechanics.</p><p><strong>Results: </strong>The mean elastic modulus (5% and 10% of strain) was 5.21 ± 1.59, 4.95 ± 1.50, and 4.10 ± 1.41 MPa in the epi-on, epi-off, and control groups, respectively. There were no significant differences in the elastic modulus between the two CXL groups (<i>P</i> = .386), but significant differences were found between both CXL groups and the control group (<i>P</i> < .001 and <i>P</i> = .005, respectively).</p><p><strong>Conclusions: </strong>This new epi-on CXL protocol provides a stiffening effect similar to the most used accelerated epi-off CXL and has the potential to clinically replace the latter, turning CXL into a real office-based procedure without the need for a sterile environment. <b>[<i>J Refract Surg</i>. 2025;41(7):e724-e730.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 7","pages":"e724-e730"},"PeriodicalIF":2.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seeing Without Light, A Mirror for My Aunt Rosi.","authors":"Raquel Maria Ruiz","doi":"10.3928/1081597X-20250530-01","DOIUrl":"https://doi.org/10.3928/1081597X-20250530-01","url":null,"abstract":"","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 7","pages":"e624"},"PeriodicalIF":3.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145212998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying Age-Related Anterior and Posterior Corneal Astigmatism Relationships: Insights for IOL Calculators and Topography-Guided LASIK Protocols.","authors":"Avi Wallerstein, Allison Bernstein, Mark Cohen, Michael Mimouni, Mathieu Gauvin","doi":"10.3928/1081597X-20250417-02","DOIUrl":"https://doi.org/10.3928/1081597X-20250417-02","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate the age-related interactions between anterior corneal astigmatism (ACA) and posterior corneal astigmatism (PCA) and their impact on total corneal astigmatism (TCA) using a high-resolution topographer in a large cohort of patients of all ages.</p><p><strong>Methods: </strong>A retrospective review of 19,317 eyes seeking refractive surgery was conducted. ACA, PCA, and TCA were measured using the Pentacam HR (Oculus Optikgeräte GmbH). Corneal data were categorized into astigmatism axes subgroups: with-the-rule (WTR), oblique, and against-the-rule (ATR), and analyzed across 10 age groups. ACA, PCA, and TCA (magnitudes and axes), along with Pearson correlation coefficients between ACA and PCA, were calculated for all groups. Correlations between \"TCA minus ACA\" and selected variables were also assessed.</p><p><strong>Results: </strong>ACA decreased by 37.6% from 18 to 65 years old, followed by a 9.8% increase after 72 years (<i>P</i> < .001). From 18 to 87 years, PCA consistently decreased by 33.3% with age (<i>P</i> < .001). TCA showed a 28% decrease from ages 18 to 59 years, followed by a 32.3% increase after 72 years (<i>P</i> < .001), which we termed a \"V-shaped\" trend. In WTR ACA eyes, the correlation between ACA and PCA decreased from <i>R</i> = 0.78 at 18 years to R ⩽ 0.48 in eyes 65 years or older. Oblique ACA eyes showed lower correlations, peaking at <i>R</i> = 0.51 at 24 years and decreasing to R = 0.02 after 72 years. ATR ACA eyes showed a mild positive correlation in midlife (<i>R</i> = 0.15; 41 years), switching to a moderate inverse correlation in older age (<i>R</i> = -0.3461; ⩾ 72 years). Higher ACA magnitude, WTR ACA axis, and young age showed strong likelihood of overcorrection if ignoring PCA in laser vision correction (LVC), intraocular lens (IOL), or phakic IOL (PIOL) refractive treatment (<i>P</i> < .0001), whereas lower ACA magnitude, ATR ACA axis, and older age were contrarily more likely to undercorrect if ignoring PCA (<i>P</i> < .0001).</p><p><strong>Conclusions: </strong>ACA versus PCA correlations are strongly age-dependent across all orientations. These findings demonstrate that incorporating age-specific correlations into modern IOL calculators could improve TCA prediction accuracy, thereby improving results in refractive IOL surgery. <b>[<i>J Refract Surg</i>. 2025;41(6):e520-e531.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 6","pages":"e520-e531"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Impact of Intraocular Higher Order Aberrations on Customized Refractive Surgery in Keratoconus.","authors":"Fengshuang Li, Bing Sun","doi":"10.3928/1081597X-20250417-01","DOIUrl":"10.3928/1081597X-20250417-01","url":null,"abstract":"","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 6","pages":"e622"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Refraction Predictability for a Capsulotomy-Fixated Intraocular Lens in Femtosecond Laser-Assisted Cataract Surgery.","authors":"Colya N Englisch, Karl T Boden, André Messias, Peter Szurman, Annekatrin Rickmann, Lisa J Müller, Anna Theresa Lorenz, Berthold Seitz, Achim Langenbucher, Philip Wakili","doi":"10.3928/1081597X-20250417-03","DOIUrl":"https://doi.org/10.3928/1081597X-20250417-03","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the predictability of postoperative refraction for a capsulotomy-fixated intraocular lens (IOL) after femtosecond laser-assisted cataract surgery (FLACS).</p><p><strong>Methods: </strong>Patients with age-related cataracts and no other eye disease who were implanted with the FEMTIS FB-313 IOL (Teleon Surgical BV) during FLACS were included. Using an IOLMaster 700 (Carl Zeiss Meditec), subjective refractive and biometric data were collected preoperatively and at a minimum of 3 months postoperatively. The prediction error (PE), defined as the actual minus predicted refraction, as well as IOL constant optimization and formula performance, were assessed, and the effect of preoperative biometry on the PE was investigated.</p><p><strong>Results: </strong>A total of 70 eyes from 48 patients were included. Hyperopic shifts resulted from applying the Haigis, Holladay 1, SRK/T, and Barrett Universal II formulas, whereas the Hoffer-QST, Pearl-DGS, Cooke K6, EVO, and Kane formulas yielded myopic shifts. The Barrett Universal II formula predicted refraction most accurately, with 48% of eyes within the limits of ±0.25 D. After constant optimization, the formulas displayed significantly lower PEs. Preoperative anterior chamber depth and lens thickness were significantly correlated with the PE. The corresponding positive parameter estimates before and after lens constant optimization were identical.</p><p><strong>Conclusions: </strong>Implantation of the capsulotomy-fixated FEMTIS IOL during FLACS is associated with increased systematic refractive PE, which is directly influenced by preoperative anterior chamber depth and lens thickness. IOL constant optimization enhances prediction accuracy. Relevant inaccuracies also persist in modern formulas, indicating that advancements beyond constant optimization might be crucial to enhance the predictability and accuracy of these calculations in clinical practice. <b>[<i>J Refract Surg</i>. 2025;41(6):e532-e541.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 6","pages":"e532-e541"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Pilot Study of Lyophilized Decellularized Storage of SMILE-Derived Lenticules.","authors":"Yiwen Fan, Xiaojun Hu, Xingtao Zhou, Meiyan Li","doi":"10.3928/1081597X-20250417-04","DOIUrl":"https://doi.org/10.3928/1081597X-20250417-04","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the feasibility and biocompatibility of a novel approach for preserving small incision lenticule extraction (SMILE) surgery-derived lenticules by integrating decellularization and lyophilization techniques.</p><p><strong>Methods: </strong>A total of 72 lenticules were divided into two distinct groups: the lyophilized decellularized storage group, which underwent treatment with Triton X-100 and sodium dodecyl sulfate, followed by freeze-drying and storage at -20°C for 24 hours; and the control group, which was stored in a sterile plastic vial at room temperature after extraction. Comprehensive analyses, including scanning electron and transmission electron microscopy, hematoxylin-eosin staining, transmittance measurements, and live/dead staining, were conducted on all lenticules to evaluate their preserved properties. SPSS v20.0 software (SPSS, Inc) was used for statistical analysis of quantitative data, and a <i>P</i> value less than .05 was considered statistically significant.</p><p><strong>Results: </strong>Histomorphology observed that the lyophilized decellularized lenticules effectively removed cellular components while preserving the structural regularity and integrity of the collagen fibers. After rehydration, the lenticules exhibited central thickening and peripheral thinning. The optical transmittance of all rehydrated lyophilized decellularized lenticules was significantly higher than that of lyophilized ones (all <i>P</i> < .05), but still lower than that of fresh lenticules (all <i>P</i> < .05). After 20 to 30 minutes of rehydration, the optical transmittance of the lenticules exceeded 80%, and both weight and optical transmittance stabilized (all <i>P</i> > .05). Furthermore, in vitro biocompatibility testing revealed relatively good morphology and comparable quantity of human keratocytes, with no detection of dead cells.</p><p><strong>Conclusions: </strong>Lyophilized decellularized storage of SMILE-derived lenticules effectively preserved the tissue morphology, optical transparency, and biocompatibility, suggesting potential for clinical application. <b>[<i>J Refract Surg</i>. 2025;41(6):e542-e550.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 6","pages":"e542-e550"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of Angle Alpha and Angle Kappa Chord Magnitude and Axes in Myopic and Hyperopic Refractive Surgery Candidates.","authors":"Yara Bteich, Hanadi Ibrahim, Karim Barake, Joseph Khalil, Jad F Assaf, Dan Z Reinstein, Timothy J Archer, Shady T Awwad","doi":"10.3928/1081597X-20250506-04","DOIUrl":"https://doi.org/10.3928/1081597X-20250506-04","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the distribution of angle alpha and angle kappa chord magnitudes, axes, and coordinates in myopic and hyperopic refractive surgery candidates.</p><p><strong>Methods: </strong>A total of 479 eyes were included and divided into myopic and hyperopic groups. Angle alpha and angle kappa chord magnitudes, chord axes, and coordinates were measured for both groups from the Galilei topographer (Ziemer Group) in addition to spherical equivalent refraction (SE) and refractive cylinder. Angle alpha and angle kappa parameters and distribution patterns were compared between groups and correlations with SE and cylinder were analyzed.</p><p><strong>Results: </strong>Angle alpha and angle kappa chord magnitudes were significantly larger in the hyperopic group (alpha: 0.52 ± 0.12 mm; kappa: 0.34 ± 0.12 mm) compared to the myopic group (alpha: 0.38 ± 0.12 mm; kappa: 0.23 ± 0.12 mm). All angle alpha chord axes and the majority of angle kappa chord axes were in the 90° to 180° and 180° to 270° quadrants, with a strong concentration in the 135° to 225° quadrant (angle alpha: 100% for hyperopia and 94% for myopia; angle kappa: 82.7% for hyperopia, 59.4% for myopia). Angle alpha x-component exhibited a positive correlation with hyperopic SE and a negative correlation with myopic SE. There was no correlation between angles alpha and kappa chord magnitudes and cylinder in both groups.</p><p><strong>Conclusions: </strong>Angle alpha chord magnitude is larger and has more consistent axis distribution than that of angle kappa. Chord magnitudes of both angles are larger in hyperopia and have stricter axis distribution compared to myopia. Understanding these relationships is key in planning laser and lens-based refractive procedures. <b>[<i>J Refract Surg</i>. 2025;41(6):e585-e593.]</b>.</p>","PeriodicalId":16951,"journal":{"name":"Journal of refractive surgery","volume":"41 6","pages":"e585-e593"},"PeriodicalIF":2.9,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}