Anterior Segment Surgery Research Articles

Artificial intelligence applications in cataract and refractive surgeries.

This review highlights the recent advancements in the applications of artificial intelligence within the field of cataract and refractive surgeries. Given the rapid evolution of artificial intelligence technologies, it is essential to provide an updated overview of the significant strides and emerging trends in this field. Key themes include artificial intelligence-assisted diagnostics and intraoperative support, image analysis for anterior segment surgeries, development of artificial intelligence-based diagnostic scores and calculators for early disease detection and treatment planning, and integration of generative artificial intelligence for patient education and postoperative monitoring. The impact of artificial intelligence on cataract and refractive surgeries is becoming increasingly evident through improved diagnostic accuracy, enhanced patient education, and streamlined clinical workflows. These advancements hold significant implications for clinical practice, promising more personalized patient care and facilitating early disease detection and intervention. Equally, the review also highlights the fact that only some of this work reaches the clinical stage, successful integration of which may benefit from our focus.

Presumed atypical late-onset toxic anterior segment syndrome after implantable collamer lens implantation: a case report

BackgroundToxic anterior segment syndrome (TASS) is a rare, noninfectious inflammation that occurs after anterior segment surgery. We report a case herein that developed presumed atypical late-onset TASS after V4c implantable collamer lens (ICL) implantation surgery.Case presentationA 26-year-old man underwent ICL implantation surgeries of both eyes on two separate days. The 1-day and 7-day postoperative routine follow-up visits revealed no abnormalities. However, one month after surgery, dense white spots attached to the posterior surface and scattered ones to the anterior surface of ICL in the left eye were noted on anterior segment examination. His uncorrected distance visual acuity (UDVA) was 20/16 in both eyes and the fundus examination was normal. Despite the absence of typical clinical manifestations, late-onset TASS was suspect and intense topical steroid was administered. After 6 weeks of tapering topical steroid therapy, the white spots disappeared and the patient had no subjective complains throughout the treatment period.ConclusionsThis case suggested that the traditionally considered acute and serious TASS could also present as delayed and insidious onset after ICL implantation surgery. Due to its variabilities, the awareness of TASS should be raised to ophthalmologists and regular follow-up visits should be emphasized to patients. Once TASS was suspected, intensive steroid therapy should be implemented in time.

Current state and future perspectives in the diagnosis of eyelid margin disease: clinical review.

The eyelid margin is vital to ocular surface integrity. Much peer-reviewed literature has been established in eyelid margin inflammation, better known as blepharitis. The purpose was to review and understand the impact of eyelid margin disease. Anterior blepharitis causes inflammation at the eyelash base, ciliary follicles, and the palpebral skin. Posterior blepharitis occurs when there is inflammation with the posterior eyelid margin disease. In common usage, the term "blepharitis" used alone almost always refers to anterior blepharitis. Classification of eyelid margin disease should be based on etiopathogenesis, location, primary vs secondary, and chronicity. Blepharitis has several etiopathologies (infectious, inflammatory, and squamous). Meibomian gland dysfunction (MGD) can refer to the functional and/or structural problems with the meibomian gland. Meibomitis (or meibomianitis) occurs when there is inflammation associated with the MGD. The presence of blepharitis and/or MGD (with or without inflammation) can affect the ocular surface and thereby affect anterior segment and cataract surgeries. This review article evaluates the differential diagnoses of eyelid margin disease, including various forms of blepharitis, MGD, and meibomitis.

Transforming the future of ophthalmology: artificial intelligence and robotics' breakthrough role in surgical and medical retina advances: a mini review.

Over the past decade, artificial intelligence (AI) and its subfields, deep learning and machine learning, have become integral parts of ophthalmology, particularly in the field of ophthalmic imaging. A diverse array of algorithms has emerged to facilitate the automated diagnosis of numerous medical and surgical retinal conditions. The development of these algorithms necessitates extensive training using large datasets of retinal images. This approach has demonstrated a promising impact, especially in increasing accuracy of diagnosis for unspecialized clinicians for various diseases and in the area of telemedicine, where access to ophthalmological care is restricted. In parallel, robotic technology has made significant inroads into the medical field, including ophthalmology. The vast majority of research in the field of robotic surgery has been focused on anterior segment and vitreoretinal surgery. These systems offer potential improvements in accuracy and address issues such as hand tremors. However, widespread adoption faces hurdles, including the substantial costs associated with these systems and the steep learning curve for surgeons. These challenges currently constrain the broader implementation of robotic surgical systems in ophthalmology. This mini review discusses the current research and challenges, underscoring the limited yet growing implementation of AI and robotic systems in the field of retinal conditions.

Clinical trial to test the safety of the EVA Nexus surgical platform

BackgroundThe EVA Nexus system offers several technical improvements over its predecessor. The newly designed Aveta cannula system for vitrectomy surgery avoids the need for removal of the valve from the infusion cannula. The chamfered leading edge of the cannula also reduces the insertion force needed. The new EquiPhaco needles in combination with SmartIOP provide excellent anterior chamber stability during phaco-emulsification surgery, enabling to work at lower infusion pressures, and the multiburst phaco mode allows easier removal of hard cataracts. The system offers a secondary active infusion line for independent control of pressure to the anterior and posterior chambers, monitoring of flow rate/reflux and warning of infusion bottle emptying. This study evaluated whether these technical improvements result in improved surgical safety.MethodsIn total, 250 eyes that underwent vitrectomy (53%) or phaco-vitrectomy (47%) using the EVA Nexus system were prospectively included. The occurrence of intraoperative adverse events was compared to that of historically operated eyes using the EVA system.ResultsThe average age of the patients was 63 years. A total of 33% of the patients were operated on for retinal detachment, 17% for macular pucker, 11% for treating floaters, 9% for removing silicone oil, 8% for macular hole repair and 22% for other diseases. In 75% of surgeries, 23 G instruments were used, and 27 G instruments were used in 25% of cases. Device issues that occurred included priming cycle issues (n = 4), eye pressure stability problems (n = 6) and vitrectome performance issues (n = 1), all of which in the first 100 patients who were included and were fixed with software updates. The frequency of surgical complications in the anterior segment was lower than that in the historically recorded surgical reports. Intraoperative events in the posterior segment included hemorrhage from retinal vessels, choroidal hematoma, iatrogenic retinal damage/tear, and subchoroidal infusion. Again, these events occurred rarely and less frequently than in the historical surgical reports.ConclusionsThe EVA Nexus provides a surgical platform that reduces the incidence of intraoperative adverse events and iatrogenic complications in both anterior and posterior segment surgery. This could increase surgical safety during cataract and vitrectomy surgery.Trial Registration number Clinicaltrials.gov: NCT05229094 Data 22/5/2021.

Evaluation of anterior segment parameters between pregnancy trimesters and postpartum with pentacam scheimflug ımaging: a prospective study

PurposeTo evaluate the effect of pregnancy on the anterior chamber, corneal parameter, and intraocular pressure measurements; and compare the results between trimesters, postpartum and non-pregnant healthy age-matched women.MethodsThis prospective study included 41 pregnant women and 53 non-pregnant women. Four measurements were taken from the pregnant women, in each trimester and postpartum third month, and once from the control group. Of the individuals included in the study, anterior chamber depth (ACD), anterior chamber volume (ACV), K1 (flat keratometry), K2 (steep keratometry), Kmean (mean value of K1 and K2), anterior chamber angle (ACA), central corneal thickness (CCT), thinnest corneal thickness (TCT), astigmatism value (AST), corneal volume (CV), biometry, axial length (AL), spherical equivalent (SFEQ), intraocular lens power (ILP), VA (visual acuity) datas were recorded.ResultsWe observed a statistically significant decrease in K2, CCT, ACD, AL and CV in the postpartum period (p = 0.025, p < 0.001, p = 0.029, p = 0.005, p = 0.004 respectively) and a statistically significant increase in ACV, CCT, and TCT as the gestational week progressed in the pregnant group (p = 0.007, p < 0.001, p = 0.025, respectively). A statistically significant decrease in IOP towards to the third trimester, and an increase in the postpartum period was observed (p < 0.001). We did not observe statistically significant changes in K1, Kmean, AST, ACA, VA, ILP, and SFEQ values.ConclusionIt is important to investigate the physiological changes that may occur during pregnancy, distinguish them from pathological changes, and avoid unnecessary treatment. We consider that it’s also important to guide the timing of anterior segment surgeries such as cataract and refractive surgery and to prescribe glasses/contact lenses.

Nontraditional approaches to sedation for anterior segment surgery: a narrative review.

Surgical and anesthetic technological advancement have made both cataract and noncataract anterior segment surgery significantly less invasive and time-intensive, facilitating the transition of some of these procedures from the operating room under monitored anesthesia care (MAC) to the office-based setting without MAC. This transition has been aided by the popularization of nonintravenous approaches to achieving patient sedation for these procedures. In this review, we discuss the literature surrounding traditional and nontraditional methods of achieving patient sedation for anterior segment surgery. Our survey of the literature suggests that nonintravenous (IV) approaches to sedation for these procedures may be just as safe, effective, and satisfactory to patients as traditional IV approaches. As anterior segment surgery becomes less invasive and less time-intensive, providers considering transitioning their cataract and anterior segment surgery out of the operating room and into the office-based setting without MAC anesthesia should consider the non-IV sedation options outlined in this review to achieve adequate patient sedation and comfort.

Long-Term Satisfaction of Oral Sedation versus Standard-of-Care Intravenous Sedation for Ocular Surgery.

Long-term patient satisfaction may influence patients' perspectives of the quality of care and their relationship with their providers. This is a follow up to a comparative effectiveness study investigating oral to intravenous sedation (OIV study). The OIV study found that oral sedation was noninferior in patient satisfaction to standard intravenous (IV) sedation for anterior segment and vitreoretinal surgeries. This study aims to determine if patient satisfaction with oral sedation remained noninferior long term. Patients were re-interviewed using the same satisfaction survey given during the OIV study. Statistical analysis involved t-tests for noninferiority of the long-term mean satisfaction score of oral and IV sedation. We also compared the original mean satisfaction score and the follow-up mean satisfaction score for each type of sedation and for both groups combined. Participants were interviewed at a median of 1225.5 days (range 754-1675 days) from their surgery. The original mean satisfaction score was 5.26 ± 0.79 for the oral treatment group (n = 52) and 5.27 ± 0.64 for the intravenous treatment group (n = 46), demonstrating noninferiority with a difference in mean satisfaction score of 0.015 (p < 0.0001). The follow-up mean satisfaction score was 5.23 ± 0.90 for oral sedation and 5.60 ± 0.61 for IV sedation, with a difference in the mean satisfaction score of 0.371 (p = 0.2071). Satisfaction scores did not differ between the original mean satisfaction score and the follow-up mean satisfaction score for the oral treatment group alone (p = 0.8367), but scores in the intravenous treatment group increased longitudinally (p = 0.0004). In this study, long-term patient satisfaction with oral sedation was not noninferior to satisfaction with IV sedation, unlike our findings with short-term patient satisfaction in our original study. Patient satisfaction also remained unchanged over time for the oral treatment group, but patients in the intravenous treatment group reported higher long-term satisfaction with their anesthesia experience compared to the immediate post-operative period.

Artificial intelligence, anterior segment and refractive surgery: Which relationship and association?

Aims/Purpose: The goal of our work is to synthesize the different fields identified by AI in refractive surgery.Methods: Research in the literature of the different manifestations of artificial intelligence related to refractive surgery.Results: Several articles including reviews reported several studies done in this direction. Lops and al introduced the PRFI (Pentacam Random Forest Index) using data from 3 different countries. The PRFI has a sensitivity of 85.2% and specificity of 96.6%. Xie and Co developed PIRSS (Pentacam InceptionResNetV2 Screening) for refractive surgery with a little number of false positive in identifying normal cornea, suspected irregular and keratoconic cornea. AI has also been used in recommending the appropriate refractive surgery and nomograms used, Kamiya and al developed an ML‐based algorithm to predict the postoperative posterior chamber phakic intraocular lens (IOL) vault using preoperative AS‐OCT images of patients undergoing phakic IOL implantation to predict the achieved vault. These examples of studies and discoveries open new horizons in refractive surgery using AI.Conclusions: AI has been successfully used in the prediction of diagnosis of various corneal disorders, including IK, keratoconus, pterygium, endothelial diseases, and corneal graft‐related complications but also in refractive surgery; certainly it has limits but next to telemedicine, 5G/6G networks, Quantum Communication Networks and Internet of Medical Things, AI is likely to form part of the new health care revolution.

Toxic posterior segment syndrome with retinal vasculitis likely caused by intraocular cotton fiber after vitreoretinal surgery – a case report

BackgroundIntraocular inflammation is common after anterior or posterior segment surgery. They typically manifest either as non-infectious inflammation of the anterior or posterior segment, known as toxic anterior or posterior segment syndrome (TPSS), or as sterile or infective endophthalmitis. In this report, we describe a rare case of TPSS following vitreoretinal surgery, presenting as hemorrhagic retinal vasculitis.Case presentationA 58-year-old male diagnosed with a left eye acute rhegmatogenous retinal detachment underwent an uneventful primary pars plana vitrectomy with silicone oil endotamponade on the same day of presentation. At presentation, there were no signs of intraocular inflammation, and his visual acuity in the affected eye was 20/200.ResultsThe retina was well-attached with silicone oil in place on the first post-operative day. Along the inferior retinal periphery, a hemorrhagic occlusive vasculitis was observed. Clinical examination revealed retained intraocular cotton fiber along the inferotemporal quadrant over the retinal surface. In addition to the standard post-operative medications, a course of systemic steroids (40 mg per day of Prednisolone tablets) was started. At the end of the first post-operative week, clinical signs of hemorrhagic retinal vasculitis were beginning to resolve, and by the end of the fourth post-operative week, they had completely resolved.ConclusionThis report describes an unusual diagnosis of TPSS after vitreoretinal surgery, most likely due to the presence of an intraocular cotton fiber. This excessive inflammation of the posterior segment usually responds to a course of topical and systemic steroids.

ROCK Inhibitors in Corneal Diseases and Glaucoma-A Comprehensive Review of These Emerging Drugs.

Rho kinase (ROCK) inhibitors have gained significant attention as emerging novel treatment options in the field of ophthalmology in recent years. The evidence supporting their efficacy in glaucoma and corneal pathology includes both in vitro and clinical studies. Among the available options, ripasudil and netarsudil have emerged as the leading ROCK inhibitors, and some countries have approved these therapeutic options as treatments for glaucoma. Various dosing regimens have been studied, including monotherapy and combination therapy, especially for patients with secondary glaucoma who are already on multiple medications. Another rising application of ROCK inhibitors includes their use as an adjunct in surgical procedures such as Descemetorhexis Without Endothelial Keratoplasty (DWEK), Descemet Stripping Only (DSO) to accelerate visual recovery, glaucoma surgeries to reduce scarring process and allow better intraocular pressure (IOP) control, or after complicated anterior segment surgery to treat corneal oedema. This article provides a comprehensive overview of the existing literature in the field, offering recommendations for prescribing ROCK inhibitors and also discussing patient selection, drug efficacy, and possible adverse effects.

The prophylactic value of TNF-α inhibitors against retinal cell apoptosis and optic nerve axon loss after corneal surgery or trauma.

Late secondary glaucoma is an often-severe complication after acute events like anterior segment surgery, trauma and infection. TNF-α is a major mediator that is rapidly upregulated, diffusing also to the retina and causes apoptosis of the ganglion cells and degeneration of their optic nerve axons (mediating steps to glaucomatous damage). Anti-TNF-α antibodies are in animals very effective in protecting the retinal cells and the optic nerve-and might therefore be useful prophylactically against secondary glaucoma in future such patients. Here we evaluate (1) toxicity and (2) efficacy of two TNF-α inhibitors (adalimumab and infliximab), in rabbits by subconjunctival administration. For drug toxicity, animals with normal, unburned corneas were injected with adalimumab (0.4, 4, or 40 mg), or infliximab (1, 10, or 100 mg). For drug efficacy, other animals were subjected to alkali burn before such injection, or steroids (for control). The rabbits were evaluated clinically with slit lamp and photography, electroretinography, optical coherence tomography, and intraocular pressure manometry. A sub-set of eyes were stained ex vivo after 3 days for retinal cell apoptosis (TUNEL). In other experiments the optic nerves were evaluated by paraphenylenediamine staining after 50 or 90 days. Loss of retinal cells and optic nerve degeneration were quantified. Subconjunctival administration of 0.4 mg or 4.0 mg adalimumab were well tolerated, whereas 40.0 mg was toxic to the retina. 1, 10, or 100 mg infliximab were also well tolerated. Analysis of the optic nerve axons after 50 days confirmed the safety of 4.0 mg adalimumab and of 100 mg infliximab. For efficacy, 4.0 mg adalimumab subconjunctivally in 0.08 mL provided practically full protection against retinal cell apoptosis 3 days following alkali burn, and infliximab 100 mg only slightly less. At 90 days following burn injury, control optic nerves showed about 50% axon loss as compared to 8% in the adalimumab treatment group. Subconjunctival injection of 4.0 mg adalimumab in rabbits shows no eye toxicity and provides excellent neuroprotection, both short (3 days) and long-term (90 days). Our total. accumulated data from several of our studies, combined with the present paper, suggest that corneal injuries, including surgery, might benefit from routine administration of anti-TNF-α biologics to reduce inflammation and future secondary glaucoma.

Visualization of surgical maneuvers using intraoperative real-time volumetric optical coherence tomography.

Ophthalmic microsurgery is traditionally performed using stereomicroscopes and requires visualization and manipulation of sub-millimeter tissue structures with limited contrast. Optical coherence tomography (OCT) is a non-invasive imaging modality that can provide high-resolution, depth-resolved cross sections, and has become a valuable tool in clinical practice in ophthalmology. While there has been substantial progress in both research and commercialization efforts to bring OCT imaging into live surgery, its use is still somewhat limited due to factors such as low imaging speed, limited scan configurations, and suboptimal data visualization. In this paper we describe, to the best of our knowledge, the translation of the fastest swept-source intraoperative OCT system with real-time volumetric imaging with stereoscopic data visualization provided via a heads-up display into the operating room. Results from a sampling of human anterior segment and retinal surgeries chosen from 93 human surgeries using the system are shown and the benefits that this mode of intrasurgical OCT imaging provides are discussed.

A comparative study: Changes in endothelial cell count in phacoemulsification with temporal clear corneal incision vs superior scleral incision in grade II &amp; III cataract

Endothelial cell loss is a key indicator of the quality of anterior segment surgery like cataract surgery. The amount and integrity of corneal endothelial cells are the two most essential factors determining corneal transparency.Aim of this study was to compare the endothelial cell loss between the superior scleral tunnel incision and the temporal clear corneal incision for phacoemulsification.Prospective observational study. This prospective observational study included 50 patients with grade II and III cataracts undergoing phacoemulsification with a temporal clear corneal incision and 50 patients with a superior scleral tunnel incision. Specular microscopy was used to count ocular endothelial cells before and one month after the surgery.The mean endothelial cell loss was significantly higher with temporal clear corneal incision (14.91% ± 5.13%) in comparison to the superior scleral tunnel incision group (6.58% ± 2.06%). A superior scleral tunnel incision is associated with less postoperative endothelial cell loss as compared to a temporal clear corneal incision and could provide a better visual outcome.

Urrets-Zavalia Syndrome after Penetrating Keratoplasty: A Case Report

Urrets-Zavalia syndrome is a dreaded complication of anterior segment surgery and the most common in patients undergoing corneal transplantation. Avoiding the prescription of mydriatic eye drops during the postoperative period is the mainstay of its therapy, which focuses on prevention. One month after having keratoplasty in the left eye, a 42-year-old man presented with Urrets-Zavalia syndrome and ocular hypertonia at 35 mmgh. Medical and surgical management were required in this situation.&#x0D; The purpose of our presentation is to describe a real-world instance of Urrets-Zavalia syndrome.

Topical Ripasudil for the Treatment of Segmental Corneal Edema: A Case Series.

Ripasudil, a rho-kinase inhibitor, has gained popularity as an adjunctive therapy after Descemet stripping only to hasten visual recovery. Ripasudil has been shown to increase corneal endothelial cell proliferation and intercellular adhesion, and decrease endothelial cell apoptosis. We present 4 cases in which persistent corneal edema after various anterior segment surgeries was successfully treated with topical ripasudil, and 1 case in which corneal edema did not improve with use of ripasudil. Retrospective chart review revealed 5 patients treated with topical ripasudil for persistent corneal edema that failed to improve with conventional, nonsurgical treatments. In each case, the patient had symptomatic, persistent, focal corneal edema which followed a surgical procedure in the anterior segment. The various etiologies of corneal edema included graft failure after Descemet stripping endothelial keratoplasty, a failed penetrating keratoplasty, and 3 cases of pseudophakic corneal edema. These patients experienced improved vision and partial or complete resolution of corneal edema after 2 to 4 weeks of topical ripasudil administered 4 times daily. One patient with pseudophakic bullous keratopathy had edema that initially improved on topical ripasudil, but after cessation of the medication, developed progressive corneal edema and required endothelial keratoplasty. In patients with focal corneal edema resulting from surgical trauma to the endothelium who failed to clear over time with conservative measures, topical ripasudil was shown to be an effective treatment option that in most cases improved vision and helped reduce the need for endothelial transplantation.

IOCT-Assisted DSAEK Tamponade for Spontaneous Corneal Perforation with Secondary Bleb Formation in Pellucid Marginal Degeneration

Intraoperative optical coherence tomography (iOCT) is used extensively in complex anterior segment surgery, providing increased precision and thereby more safety and improved clinical outcomes. In lamellar keratoplasty, the successful application of iOCT has already been described [1]. For example, the iOCT can be used for defining the cutting depth of deep anterior lamellar keratoplasty (DALK) or for visualization of potential fluid in the interface in Descemet stripping automated endothelial keratoplasty (DSAEK) [2], [3], [4]. Moreover, for the correct corneal graft positioning in Descemet membrane endothelial keratoplasty (DMEK), a marker was previously required. The iOCT allows recognition of the corneal graft orientation and further observation of the unfolding process of the graft without the need for marking [1], [5].

Commentary: Blockchain technology and its current importance in toxic anterior segment syndrome outbreak in India.

Commentary: Blockchain technology and its current importance in toxic anterior segment syndrome outbreak in India.

Surgical application of Ong speculum in simple limbal epithelial transplantation and pterygium surgery.

Ong speculum is used in glaucoma surgeries such as trabeculectomy to expose the superior part of the globe. The large inferior blade pushes the inferior conjunctival fornix, due to which the eyeball rotates downwards. It has not been used in other anterior segment surgeries before. We used this speculum in simple limbal epithelial transplantation (SLET) and pterygium surgery to expose superior bulbar conjunctiva for harvesting limbal and conjunctival grafts, respectively. As the superior conjunctiva and sclera become exposed, it facilitates the steps of harvesting limbal biopsy and conjunctival graft in SLET and pterygium surgery. This eliminated the need for a superior rectus suture or an assistant who would keep the globe rotated downwards. Its position could also be maneuvered to adjust the site of exposure when dissecting the area of pannus in SLET. Thus, it makes the superior conjunctiva more accessible.

Age-related changes in Scheimpflug corneal densitometry and their correlations with corneal topographic measurements in a healthy Chinese population.

Objective measurement of corneal densitometry (CD) values can be used to assess corneal transparency and health status, to investigate corneal diseases, and to review anterior segment surgeries. However, literature regarding the association between CD and corneal parameters in healthy adolescent and older individuals is limited. This study investigated age-related changes in Scheimpflug CD values and their correlations with age, sex, and corneal topographic parameters. This retrospective cross-sectional observational study included 347 eyes from 181 consecutive healthy Chinese participants aged between 5 and 90 years. They were divided into 9 age groups: 5-9, 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, and 80-90 years. CD and corneal topographic measurements were measured using the Oculus Pentacam. To evaluate CD, the cornea was divided into 3 layers according to depth (anterior 120 µm, central, and posterior 60 µm), and into 4 annular regions according to diameter (0-2, 2-6, 6-10, and 10-12 mm). CD across different depths and regions was positively correlated with age (all P values <0.001). Of the 3 layers of corneal thickness, CD was highest in the anterior 120 µm and lowest in the posterior 60 µm (all P values <0.05). Among the 4 annular regions spanning the corneal diameter, the lowest CD values were 6-10, 2-6, and 0-2 mm at 5-29, 30-69, and 70-89 years, respectively. The highest CD values were 10-12 mm at 5-79 years, and 6-10 mm at 80-90 years (all P values <0.05). CD values of 10-12 mm in the anterior 120 µm corneal layer were significantly lower in men than in women (Z=-2.353; P=0.019). CD of 0-10 mm in each layer was not significantly different between sexes (all P values >0.05). Corneal topographic measurements, including flat-axis keratometry (K1), steep-axis keratometry (K2), and spherical aberration, were slightly positively correlated with age and CD (all P values <0.05). However, central corneal thickness (CCT) and thinnest corneal thickness (TCT), and age or CD showed no correlation (all P values >0.05). With age, CD, keratometry, and spherical aberration gradually increased, while the corneal thickness did not change significantly.