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The article discusses the artwork of Clara Forner Martinez, a 12-year-old winner of the Miradas Infantil 2023 art contest, who symbolizes the creation of Michelangelo through a colorful representation of an eye.

The article features artist Alejandro Martinez Garcia and his work showing the face of a blind man.

Photorefractive keratectomy (PRK) was the first excimer laser procedure developed to treat refractive errors. The safety and efficacy of PRK established it as one of the most performed corneal refractive procedures worldwide. With the introduction of laser in situ keratomileusis (LASIK), and more recently keratorefractive lenticule extraction (KLEx) procedures, many corneal surgeons favor these newer corneal procedures as the first choice due to faster visual rehabilitation and less discomfort during the early postoperative period. Importantly, however, PRK remains a viable alternative for most corneal refractive candidates and there are many situations in which PRK remains the refractive procedure of choice. This review addresses the technical evolution of PRK—mechanical epithelial debridement versus alcohol-assisted epithelial removal versus excimer laser-assisted epithelial debridement (transepithelial) PRK—and reports the PRK refractive outcomes compared to other keratorefractive laser procedures. The corneal wound response associated with each PRK technique and the indications, limitations, and complications of PRK are reviewed to aid refractive surgeons to best position PRK in their overall practice. [J Refract Surg. 2024;40(10):e754–e767.] [ABSTRACT FROM AUTHOR]

Purpose: To evaluate clinical outcomes following contralateral implantation of a diffractive extended depth of focus (EDOF) and a hybrid EDOF-multifocal intraocular lens (IOL) with a violet filter in a U.S.-based population. Methods: In this prospective, non-comparative study, 60 eyes of 30 patients aged 40 years and older underwent bilateral cataract surgery and implantation of a DXR00V IOL (Tecnis Symfony OptiBlue) in the dominant eye and a DFR00V (Tecnis Synergy) IOL in the non-dominant eye. Outcome measures included uncorrected (UDVA) and corrected (CDVA) distance visual acuity, distance-corrected intermediate (DCIVA, 66 cm), near and very near visual acuity (DCNVA, 40 and 33 cm), and patient-reported outcomes. Results: At 6 months postoperatively, binocular mean UDVA and CDVA were −0.10 ± 0.07 and −0.11 ± 0.05 logarithm of the minimum angle of resolution (logMAR), respectively. The mean DCIVA was 0.26 ± 0.08 logMAR in the DXR00V eyes and 0.23 ± 0.06 logMAR in the DFR00V eyes. The mean DCNVA at 40 and 33 cm were 0.28 ± 0.12 and 0.30 ± 0.15 logMAR, respectively, in the DXR00V eyes and 0.07 ± 0.08 and 0.07 ± 0.10 logMAR, respectively, in the DFR00V eyes. The mean binocular DCIVA and DCNVA at 33 and 40 cm were 0.18 ± 0.05, 0.06 ± 0.08, and 0.06 ± 0.07 logMAR, respectively. The percentages of patients achieving spectacle independence at far, intermediate, and near distances were 100%, 100%, and 81%, respectively. Conclusions: Contralateral implantation of the diffractive EDOF and a hybrid EDOF-multifocal IOL yielded excellent binocular visual acuity at all distances, as well as high patient satisfaction and functional performance on visual tasks. [J Refract Surg. 2024;40(10):e699–e705.] [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the impact of anterior chamber phakic intraocular lens (pIOL) on swept-source optical coherence tomography (SS-OCT) biometric measurements and IOL power calculation. Methods: This retrospective analysis of 67 eyes of 49 patients with previous anterior chamber pIOL implantation analyzed the accuracy of automatic segmentation of the anterior surface of the crystalline lens and its impact on anterior chamber depth (ACD, measured from epithelium to lens), lens thickness measurements, and IOL power calculation. The sample was divided into two groups: correct detection of the anterior surface of the crystalline lens and inaccurate detection. Segmentation of eyes from the inaccurate detection group was manually corrected and ACD and lens thickness were calculated using ImageJ software. IOL power was calculated using 7 formulas for both measurements. Results: The anterior surface of the crystalline lens was mis-identified in 13 (19.4%) eyes. ACD was underestimated (Δ −0.85 ± 0.33 mm, P <.001) and lens thickness was overestimated (Δ +0.81 ± 0.25 mm, P <.001). Manual correction changed the target spherical equivalent only in the Haigis formula (P =.009). After correction for segmentation bias, the Pearl DGS, Cooke K6, and EVO 2.0 formulas showed the lowest prediction error, with the Pearl DGS showing greatest accuracy within ±1.00 diopters of prediction error range (81.0%). Conclusions: SS-OCT biometry misidentifies the anterior surface of the crystalline lens in a significant proportion, resulting in significant IOL power calculation error in the Haigis formula. Manual proofing of segmentation is mandatory in every patient with anterior chamber pIOL implantation. After correct segmentation, the Pearl DGS, Cooke K6, and EVO seem to be the best formulas. [J Refract Surg. 2024;40(8):e562–e568.] [ABSTRACT FROM AUTHOR]

Purpose: To determine factors influencing patient satisfaction scores in recipients of refractive surgery. Methods: In this prospective survey-based study, patients who had refractive surgery at an outpatient refractive clinic completed a survey of selected questions from the Press Ganey survey and the National Eye Institute Visual Function Questionnaire-25. Correlation between patient-specific variables and survey questions were assessed using Student's t-tests. Results: Fifty-three patients were recruited over a 3-year period. Most were male (55%) and middle aged (mean age: 34 years). Eleven percent underwent photorefractive keratectomy surgery and the rest had laser in situ keratomileusis, with no complications. Twenty-four percent of surveyed patients reported mild to moderate eye pain postoperatively, with the rest reporting no pain. All patients reported a full score for overall satisfaction. Conclusions: This study found persistent high patient satisfaction score across a variation of characteristics, suggesting that optimal scores are mainstay after refractive surgery procedures with excellent visual outcomes, independent of patient clinical and sociodemographic characteristics. [J Refract Surg. 2024;40(8):e539–e543.] [ABSTRACT FROM AUTHOR]

Purpose: To assess the long-term (1-year) effect of myopic femtosecond laser–assisted in situ keratomileusis (FSLASIK) on clinical characteristics and tear film biomarkers. Methods: Eighty eyes from 80 patients who underwent FSLASIK were evaluated. Ocular surface symptoms and signs were evaluated using specific questionnaires and tests. The corneal nerves and dendritic cells were examined using in vivo confocal microscopy. Corneal sensitivity was evaluated using a Cochet-Bonnet esthesiometer. Tear inflammatory cytokines and neuropeptides were evaluated using Luminex immunoassay. These examinations were performed preoperatively and at 1, 3, 6, and 12 months postoperatively. Results: Seventy-three participants completed all follow-up visits. Following FS-LASIK, ocular symptoms and signs (except Schirmer I test) worsened at 1 month but corneal and conjunctival stainings improved by 3 months. The numbers of dendritic cells and activated dendritic cells increased at the 3-month postoperative visit and recovered to preoperative levels by the 6-month visit. Ocular symptoms and corneal sensitivity recovered to preoperative levels at the 12-month visit. Tear break-up time and corneal nerve morphology were not recovered to preoperative status at the 12-month visit. Interleukin (IL)-1β, IL-17A, tumor necrosis factor-α, and substance P tear levels significantly increased at all postoperative visits compared to preoperative levels. Corneal staining scores positively correlated with tear IL-1β and IL-17A levels, whereas corneal nerve morphology positively correlated with corneal sensitivity and negatively correlated with substance P levels. Conclusions: Although most clinical variables improved at 12 months postoperatively, some tear inflammatory cytokines and substance P remain altered beyond 12 months, indicating that ocular homeostasis is not completely recovered. [J Refract Surg. 2024;40(8):e508–e519.] [ABSTRACT FROM AUTHOR]

Purpose: To identify potential risk factors that increase the likelihood of re-treatment following keratorefractive lenticule extraction (KLEx) for myopia and myopic astigmatism. Methods: This was a retrospective study of patients with myopia and myopic astigmatism who underwent KLEx using the VisuMax 500 laser (Carl Zeiss Meditec) between April 2015 and December 2020. Patients were assigned to one of two groups: the control group and the re-treatment group (if they had additional refractive surgery within 2 years of the primary treatment). The effect of different preoperative, intraoperative, and postoperative parameters on the re-treatment rate was analyzed. Results: Overall 1,822 eyes of 938 patients were analyzed. In total, 2.96% of eyes (n = 54) underwent re-treatment. The re-treated patients were more likely to be women and have high myopia, high astigmatism, steep corneas, higher ocular residual astigmatism, and residual myopic and/or astigmatic refractive error. In contrast, no significant correlation was found between re-treatment rate and age, chord µ, type of astigmatism, and corneal thickness. Conclusions: Factors associated with higher rates of retreatment after KLEx included female gender, manifest refractive high myopia (> −5.00 diopters [D]), astigmatism (> 2.00 D), spherical equivalent (> 6.00 D), ocular residual astigmatism, steeper corneas, and postoperative residual myopic and astigmatic refractive errors. This study may help to preoperatively detect patients at risk for re-treatment, improve preoperative patient counseling, and optimize patient selection to reduce future re-treatment rates. [J Refract Surg. 2024;40(6):e362–e370.] [ABSTRACT FROM AUTHOR]

Purpose: To report on the prospective evaluation of photorefractive keratectomy (PRK) in experienced ametropic naval aviators that led to the approval of refractive surgery for military pilots. Methods: This was the first study evaluating refractive surgery in naval aviators. Return to flight status after PRK and clinical outcomes and subjective and objective flight performance were evaluated. Results: A total of 785 U.S. naval aviators were enrolled in the study. Average preoperative refraction was −2.92 ± 1.73 diopters (D) (range: +5.25 to −9.13 D). By 6 months, 85.9% of eyes were within ±0.50 D and 96.4% were within ±1.00 D of emmetropia. 94.4% of eyes achieved 20/20 or better, 74.3% had 20/16 or better, and 45.2% had 20/12.5 or better uncorrected distance visual acuity (UDVA) at 6 months. A total of 78.5% of aviators met return-to-flight criteria by 4 weeks, 83.3% by 8 weeks, and 90.8% by 12 weeks following PRK. All aviators eventually returned to full flight status. Cumulative flight experience included logging more than 48,000 flight hours and 19,500 landings in the 6 months following PRK. Psychometric questionnaire results showed that 78% reported improved ability to detect other aircraft and 92% reported improved ability to land on an aircraft carrier (82% significantly improved) compared to wearing corrective lenses. No one felt their vision was worse in these dynamic environments. All aviators indicated they would undergo the procedure again and would recommend it to a fellow aviator. Conclusions: This prospective study in U.S. naval aviators determined PRK to be safe and effective in a unique patient population operating in a visually demanding and hazardous environment. The program continues to be enthusiastically supported by aviators and PRK is now allowed in all branches of the military and for National Aeronautics and Space Administration astronauts. [J Refract Surg. 2024;40(6):e371–e380.] [ABSTRACT FROM AUTHOR]

PURPOSE: Recently, the authors presented a technique that allows corneal thickness measurements along any meridian from optical sections obtained using a rotary scanning system. This paper presents three-dimensional mapping of the corneal thickness and topography of both corneal surfaces, obtained with the rotary system. METHOD: Corneal thickness and topography are computed from optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens. This lens is provided with motor driven rotation to perform automated rotary scanning of the whole cornea. Two cameras are used to capture the images of the optical sections. RESULTS: With this system, it is possible to obtain measurements of corneal thickness, as well as corneal topography. Corneal thickness and elevation maps are shown. CONCLUSIONS: Although still under development, this new optical system allows measurement of the thickness of the whole cornea as well as topographical mapping of both corneal surfaces. [ABSTRACT FROM AUTHOR]

Purpose: To compare intraoperative performance and early postoperative outcomes following phacoemulsification with two systems using active fluidics and one using gravity-based fluidics. Methods: In this prospective randomized trial, 200 eyes were randomized to the traditional and Active Sentry groups (n = 80 eyes each) where the Centurion Vision System was used with traditional or Active Sentry (Alcon Laboratories, Inc) hand-pieces, respectively, or the Infinit group (n = 40 eyes) where the Infiniti Vision System (Alcon Laboratories, Inc) was used. Within the traditional and Active Sentry groups, there were two subgroups with low (30 mm Hg) or high (55 mm Hg) intraocular pressure (IOP) used. Outcome measures compared were: cumulative dissipated energy (CDE), percentage change in central corneal thickness (CCT) at 1 day, 1 week, and 1 month, anterior chamber cells at 1 day and 1 week, rate of rise and fall of IOP following occlusion break, corneal endothelial cell density (ECD), and macular thickness 6 months postoperatively. Results: CDE was significantly lower in group II compared to the traditional group (2.96 ± 1.4 vs 4.14 ± 2.2, P =.001). With 30 mm Hg IOP, the Active Sentry group had significantly less percentage change in CCT at 1 week postoperatively compared to the traditional handpiece group (0.01% vs 0.02%, P =.008). Incidence of anterior chamber cells less than grade 2 on day 1 was significantly higher in the Active Sentry group (82.9% vs 52%, P =.03). Percentage change in ECD was significantly lower in the Active Sentry group (−0.957 vs −0.98%, P =.005). Significantly faster rise of IOP to baseline following occlusion break was seen in the Active Sentry group. Conclusions: The use of Active Sentry handpiece was associated with lower CDE, less postoperative increase in CCT, fewer anterior chamber cells, and faster rise of IOP following occlusion break. [J Refract Surg. 2024;40(5):e304–e312.] [ABSTRACT FROM AUTHOR]

Purpose: To explore a potential functional classification of intraocular lenses (IOLs) based on monocular visual acuity defocus curves (VADCs) as a primary end-point. Methods: A systematic literature search was conducted using PubMed. Two independent reviewers screened the literature for inclusion and data extraction. Inclusion criteria were full-text primary clinical studies of IOLs, published in English from 2010 onward, involving patients undergoing cataract or refractive lens exchange. A cluster analysis was conducted to explore similarities in the range of field (RoF) and increase of visual acuity from intermediate to near (ΔVA). Results: A total of 107 studies were ultimately included from the 436 identified in the systematic search, with an additional 5 studies added through the snowballing technique search. The cluster analysis was conducted using 69 reports that included monocular VADCs. Two main categories were identified based on the achieved RoF for 0.2 and 0.3 logMAR: full (FRoF) and partial (PRoF) RoF IOLs. Three subcategories were identified for FRoF depending on ΔVA: continuous (FRoF-C), smooth (FRoF-Sm), and steep (FRoF-St). On the other hand, PRoF IOLs shared the characteristic of monotonous decrease in visual acuity and were subclassified into two subcategories depending on the achieved RoF: narrowed (PRoF-N) and extended (PRoF-Ex). An additional subcategory was added to PRoF, enhanced (PRoF-En), for 7 reports alternating between PRoF-N and PRoF-Ex depending on the use of 0.2 or 0.3 logMAR as a cut-off for calculating the RoF. Conclusions: IOLs can be functionally classified into six types depending on the RoF and shape of the monocular VADC. [J Refract Surg. 2024;40(2):e108–e116.] [ABSTRACT FROM AUTHOR]

Purpose: To individually evaluate the clinical outcomes for right and left eyes in the first 3 months after laser-assisted lenticule extraction for myopia and myopic astigmatism with the use of the new ATOS femtosecond laser system (Smart-Sight; SCHWIND eye-tech-solutions). Methods: A total of 331 eyes from 168 patients (166 right eyes and 165 left eyes) consecutively treated with SmartSight lenticule extraction were retrospective analyzed after a 3-month follow-up period. Patients' mean age was 26 ± 6 years (range: 18 to 47 years) and mean preoperative spherical equivalent (SEQ) was −5.07 ± 1.92 diopters [D] (range: −1.50 to −11.25 D) with a mean astigmatism of −1.04 ± 0.85 D (range: 0.00 to −4.00 D). At 3 months of follow-up, visual acuity, SEQ and cylinder, safety index, efficacy index, corneal higher order aberrations, and intraocular pressure (IOP) were analyzed. Furthermore, refractive and visual outcomes were also analyzed for the right and left eyes individually. All lenticule extraction treatments were performed with the SmartSight treatment method of the SCHWIND ATOS femtosecond laser. Results: At 3 months after surgery, mean SEQ was −0.12 ± 0.19 D and 98% of eyes were within ±0.50 D of the SEQ. All eyes were within ±1.00 D of the SEQ. Astigmatism of 0.50 D or less was achieved in 99% of eyes. The change in Snellen lines (difference between preoperative corrected distance visual acuity and postoperative uncorrected distance visual acuity) showed a gain of one or more lines in 13% and in 85% of the eyes the same was achieved. There was a loss of one or more lines at 3 months of follow-up in 1.6%. The safety index was 1.03 and efficacy index was 1.02. No significant difference between the right and left eyes was found. Conclusions: The 3-month follow-up data show that SmartSight treatment for correction of myopia and myopic astigmatism with the SCHWIND ATOS is a safe, efficient, and accurate procedure. It provided excellent results in terms of visual recovery, predictability, and higher order aberrations. [J Refract Surg. 2024;40(1):e30–e41.] [ABSTRACT FROM AUTHOR]

Presents a response by Malvina B. Eydelman, Bruce Drum, Jack Holladay, Gene Hilmantel, Guy Kezirian, Daniel Durrie, R. Doyle Stulting, Daniel Sanders and Bonita Wong to a letter to the editor about their article "Standardized Analysis of Correction of Astigmatism by Laser Systems that reshape the Cornea" in the 2006 issue.

PURPOSE: The optical quality of retinal images is dependent on the refracting elements of the eye including the nominally aspheric cornea and crystalline lens. This paper presents a retrospective theoretical analysis of the impact of corneal asphericity on the quality of retinal images. Clinical data are from the VISX Incorporated CustomVue IDE. METHOD: Topography, contrast sensitivity, and visual acuity data were collected from 278 myopic eyes before and after wavefront-guided laser surgery. The measured corneal surface of each eye was fitted to a conic, and a Q-value was computed for a 5.5-mm pupil. A model eye was used to simulate various amounts of optical asphericity. RESULTS: Preoperatively, most corneas exhibited negative conic shape constants. Postoperatively, corneas were about equally divided between positive and negative conics. There was no statistically significant correlation between the shape of the cornea and the subjects' perceptions of image quality including contrast sensitivity and visual acuity. Simulations showed that the corneal Q-value can vary from more to less prolate depending upon the shape of the internal surface. CONCLUSION: Following wavefront-guided laser in situ keratomileusis (LASIK), contrast sensitivity is usually good and is not dependent upon the corneal conic shape. Better visual outcomes are more likely with a customized shape than a standard best conic shape. [ABSTRACT FROM AUTHOR]

PURPOSE: This paper reviews the currently used visual function diagnostic metrics, acuity, refractive error, and contrast sensitivity, and suggests ways to create new metrics using the information that has recently become available due to advances in measuring the higher-order aberrations of the eye. Particularly, emphasis is placed on finding metrics that address certain aspects of vision rather than on general metrics. METHODS: Two metrics based on the modulation transfer function are introduced, the Visual Quality Factor (VQF), which is a value based on the modulation transfer function between the spatial frequencies of 3 and 12 cycles per degree (c/deg) giving a measure of the overall degradation of visual quality due to aberrations, and the Subjective Sharpness Factor (SSF), which is a value based on the modulation transfer function between the spatial frequencies of 15 and 40 c/deg, giving a measure of the decrease in perceived image "sharpness" due to aberrations. Two metrics based on the point spread function are suggested, Point Spread Quality (PSQ), which is a measure of the "compactness" of the point spread, and Multiplicity Factor, which is a measure of the multiplicity of perceived images by measuring the number of discrete peaks in the point spread function. RESULTS: The VQF and SSF values for both monochromatic and polychromatic cases are analyzed with regard to the number of acuity letters lost using data from a published study. CONCLUSIONS: The SSF is found to be the best overall correlate with acuity performance if the degradation of the letter stimuli is not excessive. [ABSTRACT FROM AUTHOR]

Focuses on the 5th International Congress of Wavefront Sensing and Optimized Refractive Corrections which took place at the Fairmont Chateau Whistler Resort, Whistler, British Columbia, Canada on February 21 to 24, 2004. Organizers of the meeting; Information on two review papers on ablation design; Hottest topic of the Congress.

Purpose: To provide a comprehensive analysis of the most highly cited modern articles in refractive surgery, those published between 2010 and 2020, and compare these results to a list of the most highly cited articles in refractive surgery from all timepoints. Methods: The Scopus database was searched for articles pertaining to refractive surgery using multiple search terms to identify the top 100 most cited articles in refractive surgery published between 2010 and 2020. Articles were reviewed for relevance and ranked based on total citations accrued. Results: The 100 most cited modern articles in refractive surgery were identified. The article with the most citations by Sekundo et al has garnered nearly 600 citations to date. Almost all articles (88%) included in the top 100 had 200 or more citations. Intraocular lens (34 articles), keratorefractive lenticule extraction (ie, small incision lenticule extraction) (27 articles), and laser in situ keratomileusis (17 articles) were the predominant topics. Aarhus University in Denmark generated the most articles (5), whereas numerous articles originated from multiple countries, including the United States (16), United Kingdom (10), France (8), Spain (8), China (7), and Germany (7). Conclusions: This list provides a comprehensive assessment of the most cited modern articles in refractive surgery and demonstrates key focuses and trends in the field over the past decade. Intraocular lens and keratorefractive lenticule extraction were the primary topics. There was a broader representation of procedures, topics, authors, and country of origin as compared to prior work. [J Refract Surg. 2023;39(11):784–790.] [ABSTRACT FROM AUTHOR]

The authors discuss the study "The Effects of Whole-Corneal and Whole-Eye Higher Order Aberrations on the Discrepancy Between Refractive and Corneal Astigmatism Between Refractive and Corneal Astigmatism in Otherwise Healthy Candidates for Refractive Surgery" by Kepa Balparda et al. They examine the effect of differential corneal higher order aberrations (HOAs) on axis discrepancy. They suggest that HOAs do not account for the difference between refractive and corneal astigmatism axis.

Purpose: To evaluate the levels of habituation and its influence on outcome satisfaction in patients who underwent bilateral multifocal intraocular lens (IOL) implantation. Methods: A total of 24 patients underwent bilateral multifocal IOL implantation surgery with the AcrySof IQ PanOptix trifocal diffractive IOL (Alcon Laboratories, Inc) following cataract extraction or for refractive purposes. Data were collected 3 and 6 months after surgery, which included subjective refraction, corrected and uncorrected visual acuity (distance, intermediate, near), a contrast sensitivity test, simulation with the Halo & Glare Simulator (Carl Zeiss Meditec AG), two visual quality surveys, and a slit-lamp examination by an ophthalmologist. Results: All patients were spectacle independent for distance vision and 92% (n = 22) needed no visual aid for near vision. Minor visual acuity improvement was detected between both examinations at monocular uncorrected distance visual acuity (P =.025). Improvements of presence, size, and intensity of visual disturbances were not statistically significant, but overall patient satisfaction (P =.009) and Weber-Contrast sensitivity under mesopic conditions (P =.029) increased significantly. Conclusions: Diffractive multifocal IOLs are a stable treatment for presbyopia and/or cataract with a high spectacle independence rate. Visual disturbances caused by their optics do not decrease significantly between 3 and 6 months after surgery. Habituation and neuroadaptation play a significant role in patient satisfaction and contrast sensitivity during and possibly beyond that period. [J Refract Surg. 2023;39(8):510–517.] [ABSTRACT FROM AUTHOR]

Purpose: To investigate clinical characteristics and tear film biomarkers of patients with chronic dry eye disease (DED) following femtosecond laser–assisted laser in situ keratomileusis (FS-LASIK). Methods: Patients were divided into the chronic DED after FS-LASIK (n = 36), DED without FS-LASIK (n = 39), and normal control (without FS-LASIK; n = 34) groups. Dry eye, pain, and psychological-related symptoms were evaluated using the Ocular Surface Disease Index (OSDI), Numerical Rating Scale (NRS), Neuropathic Pain Symptom Inventory Modified for the Eye (NPSI-Eye), and Hamilton Anxiety Rating Scale (HAMA) questionnaires. Ocular surface parameters, tear cytokines, and neuropeptide concentrations were evaluated with specific tests. Results: The DED after FS-LASIK group showed higher corneal fluorescein staining scores, but lower OSDI and NPSI-Eye scores than the DED without FS-LASIK group (all P <.05). Corneal sensitivity and nerve density decreased in the DED after FS-LASIK group (all P <.01). Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-17A, IL-23, alpha-melanocyte stimulating hormone (α-MSH), oxytocin, and substance P levels were highest in the DED after FS-LASIK group, followed by the DED without FS-LASIK and normal control groups (all P <.05). Interferon-γ and neurotensin levels were only significantly higher in the DED after FS-LASIK group (all P <.05). Conclusions: Patients with chronic DED after FS-LASIK showed milder ocular symptoms, greater epithelial damage, and higher levels of tear inflammatory cytokines and neuropeptides than patients with DED without FS-LASIK, indicating that the nervous and immune systems may play significant roles in FS-LASIK-related chronic DED development. [J Refract Surg. 2023;39(8):556–563.] [ABSTRACT FROM AUTHOR]

Presents a letter to the editor in response to the article "Standardized Analysis of Correction of Astigmatism by Laser Systems that reshape the Cornea," by M. B. Eydelman, B. Drum, J. Holladay, G. Hilmantel, G. Kezirian, D. Durrie, R. D. Stulting, D. Sanders and B. Wong in the 2006 issue.

Purpose: To provide a comprehensive analysis of the most highly cited articles and authors in refractive surgery. Methods: The Scopus database was searched for articles pertaining to refractive surgery using multiple search terms to identify the top 100 most cited articles in refractive surgery. A publicly available database of more than 100,000 scientists that provides standardized information on multiple variables resulting in a composite indicator (C score) was searched to identify refractive surgery authors. A refractive surgery–specific composite score was created using only the authors' publications that were directly related to refractive surgery. Results: The 100 most cited articles and 40 refractive surgery authors with the highest ranked C score were identified. The article with the most citations by Trokel et al has garnered nearly 800 citations to date. All articles included in the top 100 had 200 or more citations. The peak publication years were 1998 to 2001. Laser in situ keratomileusis (22), photorefractive keratectomy (18), and postoperative corneal ectasia and/or corneal biomechanics (16) were the most represented topics. Emory University generated the most articles (7) and the majority of publications (48%) originated in the United States. Steven E. Wilson, MD, had the highest refractive C score and Jorge L. Alió, MD, PhD, had the most refractive surgery articles and citations. Among all authors listed, the average number of refractive surgery publications was 97, with 35% of the group having more than 100 refractive surgery articles published. All authors on the list had more than 2,000 citations for their refractive surgery articles, whereas 38% had 4,000 or more citations. Conclusions: This list provides a comprehensive assessment of the most cited articles and authors in refractive surgery and demonstrates key focuses and trends in the field over time. [J Refract Surg. 2023;39(2):78–88.] [ABSTRACT FROM AUTHOR]

Purpose: To report the outcomes of PRESBYOND Laser Blended Vision LASIK (Carl Zeiss Meditec AG) in presbyopic commercial and military pilots requiring Class 1 aeromedical certification. Methods: This was a retrospective study of 23 consecutive pilots who underwent PRESBYOND Laser Blended Vision LASIK. Postoperative visits were conducted at 1 day and 1, 3, and 12 months. Standard outcomes analysis was performed using the data at 12 months. Objective quality of vision measures including mesopic contrast sensitivity (CSV-1000; VectorVision), Ocular Scatter Index (HD Analyzer; Keeler), and straylight (C-Quant; Oculus Optikgeräte GmbH) were determined before and 3 months after surgery. A questionnaire to assess the functional vision of pilots before and after surgery was derived to record subjective outcomes. Results: Of the 23 pilots treated, data were available at 12 months for 22 pilots (95.7%) and at 3 months for 1 pilot (4.3%). Median age was 55 years (range: 42 to 65 years). At 12 months, binocular uncorrected distance visual acuity was 20/20 or better in 100% and 20/16 or better in 52% of pilots. Binocular uncorrected intermediate visual acuity was J3 in 73%, J5 in 95%, and J10 in 100% of pilots. Binocular uncorrected near visual acuity was J1 or better in 78% and J2 or better in 100% of pilots. Mean postoperative spherical equivalent refraction relative to the target was −0.04 ± 0.34 diopters (D) (range: −0.63 to +0.63 D), with 93% within ±0.50 D. There was a statistically significant increase in contrast sensitivity at 3, 6, 12, and 18 cpd. C-Quant straylight was 1.07 ± 0.16 before surgery and 1.06 ± 0.16 at 1 to 3 months after surgery (P =.705). All pilots achieved Class 1 medical certification from the United Kingdom Civil Aviation Authority and resumed flying. All pilots reported improved functionality compared to the previous vision correction method. Conclusions: PRESBYOND Laser Blended Vision LASIK enabled presbyopic commercial pilots to continue to fly without the need for glasses. With consideration of the visually challenging cockpit environment, PRESBYOND Laser Blended Vision LASIK provides clear continuous vision for tasks at near, intermediate, and far distance. Class 1 pilots reported a subjective improvement in visual tasks and comfort following surgery. [J Refract Surg. 2023;39(1):6–14.] [ABSTRACT FROM AUTHOR]

Comments on the amalgamation of International Society of Refractive Surgery and the American Academy of Ophthalmology (AAO). Brief history of the organizations; Impact of the advent of radial keratotomy in the U.S. in the 1980s on the field of ophthalmology; Reason for the impetus to advance refractive surgery within the AAO in 2001.

PURPOSE: To develop a new ectasia risk model through artificial intelligence (AI) and machine learning, enabling the creation of an integrated method without a cut-off point per risk factor, and subsequently better at differentiating patients at higher risk of ectasia with normal topography. METHODS: This comparative case-control study included 339 eyes with normal preoperative topography, with 65 eyes that developed ectasia after laser in situ keratomileusis (ectasia group) and 274 eyes that did not develop ectasia (control group). The AI model used known risk factors to engineer 14 additional ones, totaling 20 features. In this methodology, no variable is used in isolation because its cut-off point is never considered. All separation between cases and controls is made through the interaction detected by the machine learning model that gathers the variables considered relevant. The ability to correctly separate ectatic cases identified as high risk, ectatic cases wrongly classified as low risk, and controls were illustrated by the diagram t-distributed stochastic neighbor embedding (t-SNE). RESULTS: Only two original variables (percent tissue altered and corneal thickness) and two derived from the feature engineering process (derivative percent tissue altered and age weighted value) were selected by the final AI model (ie, best performing AI-based model to separate patients at higher risk). The t-SNE visualization demonstrated the greater ability to differentiate between patients considered at risk by the AI-based model, without a cut-off point, compared to all other methods used alone (P <.0001). CONCLUSIONS: This study describes a new AI-based model that integrates different risk factors without a cut-off point, increasing the number of cases correctly identified as at higher risk. [J Refract Surg. 2022;38(11):716–724.] [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the 36-month clinical outcomes of under-flap stromal bed CXL (ufCXL) and report on its ability to stabilize post-laser in situ keratomileusis (LASIK) ectasia. METHODS: This case series included 20 eyes with diagnosed early post-LASIK ectasia treated with ufCXL. Inclusion criteria were early, mild post-LASIK ectasia, defined as new-onset postoperative manifest refraction cylinder of 1.50 diopters (D) or less, with new topographic inferior steepening consistent with ectasia, uncorrected distance visual acuity of 20/40 or better, and corrected distance visual acuity of 20/25 or better. The existing LASIK flap was lifted, 0.25% isotonic riboflavin was applied directly to the stromal bed, the flap was repositioned, and 18 mW/cm2 ultraviolet light was applied for 5 minutes to the corneal flap surface. Post-ufCXL ophthalmic data were compared to pre-ufCXL baseline measurements. RESULTS: Visual outcomes were maintained pre-ufCXL to 36 months post-ufCXL, with preserved safety index (P =.6545), efficacy index (P =.4980), spherical equivalent accuracy (P =.1536), defocus equivalent accuracy (P =.1032), central corneal thickness (P =.5196), and corneal irregularity indices at 3 mm (P =.8548) and 5 mm (P =.3399). Refractive astigmatism significantly decreased from 0.83 to 0.55 D pre-ufCXL to post-ufCXL (P =.0439), as did maximum keratometry from 42.40 to 42.00 D pre-ufCXL to post-ufCXL (P =.0420). The ufCXL demarcation line depth was 336 ± 21 µm post-ufCXL, with normal endothelial cell density (2,574 ± 203 cells/mm2). Only 1 of 20 eyes showed evidence of progression of 1.00 D in maximum keratometry. CONCLUSIONS: The ufCXL procedure shows promise in stabilizing early post-LASIK ectasia. Visual function, refractive astigmatism, maximum keratometry, and corneal irregularity indices were statistically maintained at 36 months postoperatively. [J Refract Surg. 2022;38(8):511–519.] [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate postoperative subjective quality of vision in patients who underwent Implantable Collamer Lens (ICL) (STAAR Surgical) implantation for correction of myopia and to identify potential predictive parameters. METHODS: In this single-center cross-sectional study, a total of 162 eyes of 81 patients (58 women, 23 men) who underwent ICL implantation were analyzed. The Quality of Vision (QOV) questionnaire was used to assess patient-reported outcomes. Baseline characteristics (eg, age), treatment parameters (eg, surgical corrected refraction), and refractive (eg, residual refraction) and visual (eg, uncorrected distance visual acuity) outcomes were analyzed regarding their effect on QOV. RESULTS: Mean age was 33.3 ± 7.0 years (range: 21 to 51 years) and mean preoperative spherical equivalent was −8.42 ± 2.49 diopters (D) (range: −3.25 to −14.38 D). After a mean postoperative follow-up period of 19 ± 14 months (range: 6 to 54 months), the safety index score was 1.23 ± 0.21 and the efficacy index score was 1.17 ± 0.22. The mean QOV scores were 35.5 ± 11.3, 32.2 ± 11.1, and 23.3 ± 16.1 for frequency, severity, and bothersomeness, respectively. The most frequently experienced symptoms were halos (90.1%) and glare (66.7%). Halos appeared in 66.7% of the patients "occasionally" and 5 of them (6.2%) experienced them "very often." Only 1 patient (1.2%) classified halos as "very bothersome." Patients older than 36 years reported visual symptoms more frequently (P <.05) and showed higher bothersomeness scores (P =.01). CONCLUSIONS: Halos are the most commonly perceived long-term visual disturbance after myopic ICL implantation with a central hole. Visual symptoms can persist more than 6 months postoperatively, causing only minor disturbances in most cases. Older patients seem more prone to experiencing these symptoms. [J Refract Surg. 2022;38(5):280–287.] [ABSTRACT FROM AUTHOR]

PURPOSE: To develop and apply a new evaluation device for testing excimer laser ablation that allows a three-dimensional test of the characteristics of the imparted ablation. METHODS: A specially designed PMMA hemisphere with a 43.00-D curvature was developed, and results obtained with different algorithms and profiles of curvature with the Nidek EC-5000 excimer laser were evaluated. Topography, OPD-scan, wavefront, and keratoscopy were performed before and after ablation. RESULTS: The test hemisphere proved to be a reliable tool, allowing repeatable ablation results, precise calibration results, as well as experimental evaluation and comparison of new profiles. CONCLUSION: This new PMMA hemisphere can be used to improve the understanding of commonly used ablation algorithms and profiles, as well as in the daily safety routine and the experimental development and evaluation of advanced treatment solutions in excimer laser refractive surgery. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the changes in tear neuromediators and corneal subbasal nerve plexus following small incision lenticule extraction (SMILE) and to study its association with different refractive power of corrections. METHODS: Thirty patients were included for tear neuromediator analysis (40 eyes) and corneal nerve analysis using in vivo confocal microscopy scans (20 eyes). Tear samples were collected preoperatively and 1 week and 1, 3, 6, and 12 months postoperatively and analyzed for the substance P, calcitonin gene-related peptide (CGRP), and nerve growth factor (NGF) concentrations using the enzyme-linked immunosor-bent assay (ELISA). RESULTS: Corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), and corneal nerve branch density (CNBD) decreased significantly postoperatively, then gradually increased from 3 months onward, but did not recover to the baseline levels at 12 months. Tear substance P and CGRP levels remained stable over 12 months. Tear NGF levels demonstrated a small peak at 1 week before decreasing significantly compared to preoperative levels at 6 months (P =.03) and 12 months (P =.007). The 1-month reduction in CNFL, tear substance P, and CGRP concentrations were significantly correlated with the corrected spherical equivalent (SE) (r = 0.71 for CNFL; r = −0.33 to −0.52 at different time points for substance P and CGRP, respectively, all P <.05). Compared to the low to moderate myopia group, the high myopia group (corrected SE greater than −6.00 diopters) had a significantly greater decrease in CNFD, significantly higher tear substance P concentrations at 1 week, 1 month, and 6 months, and significantly higher tear CGRP concentrations at 1 and 6 months. CONCLUSIONS: These results provide new insight into the neurobiological responses and their potential implications in corneal nerve damage and recovery after SMILE. High myopia treatment was associated with greater corneal denervation and neuroinflammation. [J Refract Surg. 2021;37(8):516–523.] [ABSTRACT FROM AUTHOR]

The purpose of this article is to review the current status of presbyopia amelioration with surgical and pharmacologic procedures that partially compensate for loss of accommodation in advance of cataract surgery and lens replacement. Over the last few years, several corneal surgical and topical pharmacological approaches for the treatment of presbyopia have been introduced to the marketplace or are in the developmental pipeline. The approaches vary in invasiveness, duration of effect, reversibility, risk/benefit ratio, and clinical results. The advantages and disadvantages for each are discussed. Corneal surgical interventions aim to provide improved near and intermediate vision in patients with presbyopia through refractive means that extend ocular depth of focus through shape modification. The use of miotic drops or corneal lamellar implants extend depth of focus with the "pinhole" aperture size reduction effect. Unlike in adults younger than 40 years, the refractive status of the patient with presbyopia is not stable. Hence, procedures that provide a permanent refractive change may not provide long-term full correction; eye drops or other treatments that are self-reversing in time or are easily reversible may be used as needed. On the horizon, procedures are being explored that may add years of functional lens accommodation by preserving the deformable gel properties of the lens. [J Refract Surg. 2021;37(6 Suppl):S20–S27.] [ABSTRACT FROM AUTHOR]

Presents an introduction to a series of articles published within the issue, regarding wavefront sensing and aberration-free refractive eye correction.