Laser in situ keratomileusis versus Artisan lens implantation in correcting ametropia after penetrating keratoplasty for keratoconus.

PURPOSE: To compare the long-term safety and efficacy of laser in situ keratomileusis (LASIK) with Artisan phakic intraocular lens implantation to correct refractive errors after penetrating keratoplasty (PK) for keratoconus. METHODS: This retrospective comparative interventional case series included a total of 33 consecutive keratoconus eyes that had previous PK and received subsequent LASIK (n = 16) or Artisan lens implantation (n = 17) were included in this study. Outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive error, and complications. RESULTS: Postoperatively, the UDVA of ≥20/40 was achieved in none of the LASIK group compared to 62.5% of eyes in the Artisan group (P < 0.001); the respective values for CDVA of ≥20/40 were 87.5 and 94.1% (P = 0.51). Spherical equivalent refraction decreased from - 6.97 ± 1.50 D preoperatively to - 4.20 ± 2.05 D postoperatively in the LASIK group (P < 0.001) and from - 10.79 ± 2.15 D preoperatively to - 2.13 ± 1.23 D postoperatively in the Artisan group (P < 0.001). There was no significant change in the refractive astigmatism in LASIK group (P = 0.30) or Artisan group (P = 0.11). The efficacy and safety indices were significantly better for Artisan (0.82 ± 0.34 and 1.13 ± 0.30, respectively) than for LASIK (0.22 ± 0.17 and 0.85 ± 0.24, respectively, P ≤ 0.006 for both comparisons). While refractive error changed significantly from postoperative year 3 to the final visit in the LASIK group, it remained stable in the Artisan group through follow-up period. No significant complications were observed in any group. CONCLUSION: Artisan lens implantation provided superior and stable visual outcomes compared to LASIK for the management of post PK refractive errors in keratoconus eyes.

Mechanical removal of epithelial hyperplasia leads to successful treatment of irregular astigmatism.

BACKGROUND: Corneal epithelium remodeling in response to changes in the anterior corneal surface (keratoconus, corneal refractive surgery) is well-documented in the literature. However, several conditions may induce a different behavior of the epithelium, in which focal areas of epithelial thickening induce irregular astigmatism. This case report presents a highly unusual case of irregular astigmatism induced by an epithelial hyperplasia of unknown etiology, which was treated by the mechanical removal of only the epithelium. CASE PRESENTATION: A 29-year-old woman underwent implantable collamer lens implantation to correct myopia. The patient provided written informed consent. The procedure was uneventful in both eyes. Twenty months later, she complained of decreased visual acuity in the left eye (uncorrected distance visual acuity (UCDVA) was 20/30; corrected distance visual acuity was 20/20 with + 1.00 -2.25 × 170). Corneal topography revealed a nasal steepening in the left eye. Although the corneal thickness map was normal, epithelial thickness mapping revealed a localized nasal area of epithelial hyperplasia in the left eye that matched the area of steepest curvature. Slit lamp examination showed a total clear cornea with no signs of abnormality. The patient´s medical history was unremarkable and a case of epithelial hyperplasia of unknown etiology, without active inflammation, was considered. The decision was made to perform a mechanical removal of the corneal epithelium after application of diluted alcohol. One month after the procedure, the topography of the epithelized cornea showed a regular bow tie pattern and UCDVA improved to 20/20. No recurrence of the epithelial hyperplasia was detected after twenty-one months. CONCLUSIONS: Focal epithelial hyperplasia may induce irregular astigmatism. Epithelial thickness mapping is a very helpful technological tool to assess cases with irregular topography. De-epithelization as an isolated procedure may be useful for the successful management of these cases. Further research is required to understand the mechanism that triggers the spontaneous development of a focal epithelial hyperplasia.

Corneal endothelial ring following the implantation of toric implantable collamer lenses with a central hole: a case report.

BACKGROUND: To report a case of a corneal endothelial ring after toric implantable collamer lens (TICL, V4C) implantation in the right eye of a patient. CASE PRESENTATION: A 36-year-old woman with refractive errors of -8.00 DS/-2.00 DC * 8° in the right eye and - 6.50 DS/-1.75 DC * 177° in the left eye developed a corneal endothelial ring in the right eye on the first day after receiving TICLs implantation for treatment of high myopic astigmatism, which has not been previously reported as a complication of ICLs implantation. At 1 day postoperatively, the uncorrected distance visual acuity (UDVA) was 20/16, the intraocular pressure as measured by non-contact tonometry was 16.9 mmHg, and the vault as measured by anterior segment optical coherence tomography was 1238 µm. The eye was quiet and there was no unusual anterior chamber reaction. However, slit-lamp examination revealed an endothelial annular lesion of approximately 0.4 mm in diameter in the central part of the cornea, which was gray-white in color. The shape of the ring was the same as that of the central hole of the TICL. Specular microscopy showed that the mean endothelial cell density (ECD) of the ring significantly decreased to 1442 ± 263 cells/mm2, while the other part was still normal (2852 ± 103 cells/mm2). After 9 days of corticosteroid treatment and intense lubrication, the patient had a clear cornea, increased ECD (1532 ± 653 cells/mm2), and a good UDVA (20/16). CONCLUSION: This case suggests that a few hours after ICL V4C implantation, with a large vault, corneal displacement caused by an air puff would make the endothelium close to or even contact the ICL, producing a corneal endothelial ring. After ruling out various possible factors, we speculated that the endothelial ring was developed due to the non-contact tonometer air puff before slit-lamp evaluation, and this phenomenon was recorded by Corvis, which confirmed that the cornea could come in contact with the ICL due to gas shock. This "contact" may cause transient corneal endothelial damage.

Changes in Vector Astigmatism After Superotemporal Versus Temporal Clear Corneal Incision Cataract Surgery.

PURPOSE: To investigate vector and refractive astigmatism changes after superotemporal versus temporal clear corneal incision cataract surgery. METHODS: Patients were diagnosed with age-related cataract with corneal astigmatism < 1.5 diopters (D) and were divided into two groups: superotemporal incision (R group) and temporal incision (L group). Uncorrected visual acuity, manifest refraction, corneal topography, anterior segment optical coherence tomography was performed pre- and six months postoperatively. Total ocular astigmatism, corneal astigmatism, vector of surgically induced corneal astigmatism (SICA), non-corneal ocular residual astigmatism (N-CORA), postoperative intraocular lens decentration and tilt were analyzed.  Results: Thirty-eight subjects were included: 21, R group; 17, L group. After surgery, the N-CORA decreased significantly from 1.17±0.72 D to 0.73±0.47 D in all patients (P=0.001), 1.03±0.52 D to 0.70±0.40 D in the R group (P=0.005) and 1.35±0.90 D to 0.78±0.55 D in the L group (P=0.033). Significant differences between t:he R and L groups were found in the postoperative meridian of anterior corneal astigmatism (75.95±52.50 vs 116.79±47.29; P=0.017), total corneal astigmatism (51.65±42.75 vs 95.20±57.32; P=0.011), J45 change vector of SICA in the anterior cornea (-0.10±0.18 vs 0.00±0.11; P=0.048) and total cornea surface (-0.14±0.17 vs 0.03±0.12; P=0.001).  Conclusion: The N-CORA decreased significantly after cataract surgery. Superotemporal and temporal incisions caused differences in the meridian components of oblique astigmatism in some patients but did not have a significant effect on the magnitude of corneal astigmatism.

[Optical properties of the cornea after different modifications of penetrating keratoplasty]. / Opticheskie svoistva rogovitsy posle razlichnykh modifikatsii skvoznoi keratoplastiki.

PURPOSE: Comparative analysis of optical properties of the cornea after different modifications of penetrating keratoplasty. MATERIAL AND METHODS: The study included 56 patients (56 eyes) divided into three study groups according to the surgery technique. Group I included 17 patients (17 eyes) after one-piece mushroom keratoplasty, group II - 21 patients (21 eyes) after two-piece mushroom keratoplasty and group III - 18 patients (18 eyes) after penetrating keratoplasty. In addition to standard examination methods, before surgery and in the course of the follow-up all patients underwent software-powered corneal densitometry on the anterior segment analyzer (Pentacam HR, "Oculus", Germany), as well as an assessment of the degree and regularity of postoperative astigmatism. RESULTS: Comparison of the obtained results revealed with a high degree of confidence higher values of the total specific light scattering after two-piece mushroom keratoplasty throughout the entire observation period (p<0.05). At the same time, there was no statistically significant difference in visual acuity between the three study groups (p>0.05). A statistically significant increase in the level of induced astigmatism was revealed after penetrating keratoplasty. CONCLUSION: The observed increase in light scattering after two-piece mushroom keratoplasty does not lead to a decrease in visual acuity. The interface in the optical zone of the cornea formed by a microkeratome does not affect the degree and regularity of induced astigmatism.

Factors affecting surgically induced astigmatism in manual small-incision cataract surgery.

Cataract is the most common cause of avoidable blindness in the world. While cataract surgery is continually evolving, manual small-incision cataract surgery (MSICS) still remains highly relevant, especially with the threat of the coronavirus disease 2019 (COVID-19) still looming large over the world. MSICS today has a renewed significance, since it does not involve the use of any advanced machinery and relies mainly on easily sterilizable instruments, thereby making it a safe and inexpensive option. A self-sealing valvular tunnel entry forms the basis of MSICS, and proper positioning and construction of the tunnel is imperative to the success of the surgery. With more and more people demanding spectacle independence after surgery, it becomes important to have a thorough understanding of the factors that may influence surgically induced astigmatism in MSICS. These include the incision location, size and shape, configuration of the sclero-corneal tunnel, pre-existing ocular pathology, role of sutures, amongst others. With proper knowledge, many of these factors can be modulated to achieve best results.

Postoperative astigmatic considerations in manual small-incision cataract surgery - A review.

Cataract remains a major cause of visual impairment worldwide including in India. The sutureless manual small-incision cataract surgery (MSICS) as an alternative to phacoemulsification, gives equivalent visual results at lower expenses. Still the procedure is often discredited for higher astigmatism due to the larger size of the incision. High astigmatism is an important cause of poor uncorrected visual acuity after cataract surgery. However, there are enough studies in the literature to prove that surgically induced astigmatism (SIA) can be minimized and also eliminated by adopting appropriate wound construction techniques during surgery. Even pre-existing astigmatism if any can be neutralized by changing wound architecture during surgery. Here, we review the various techniques of scleral tunnel construction described in the literature to care for postoperative astigmatism in MSICS.

Evaluation of scleral incisions and their effects on corneal curvature in manual small-incision cataract surgery.

Purpose: Incisions in cataract surgery can be modified in various ways in terms of size, shape, and axis to reduce or tailor astigmatism. This study was conducted to examine the effect of site (superior vs, temporal) and shape (frown vs. V-shaped, chevron) of scleral incisions for cataract surgery on corneal curvature. Methods: The prospective study was carried out on 200 consecutive patients with senile cataract and who were planned for surgery at a tertiary eye hospital in north India. The placement of the incision was decided by the steeper corneal meridian-whether superior or temporal-and then patients of these two groups were randomized for frown and V-shaped incision; in this way, four groups of 50 patients each were formed. Follow-up was done on day 1, at 2 weeks, 4 weeks, 8 weeks, and 12 weeks. At each follow-up, post-operative keratometry with routine postoperative examination was done. The results were statistically analyzed by using student's t-test, Chi-squared test, and the Pearson correlation coefficient. Results: In all the four groups, the difference of preoperative astigmatism and surgically-induced astigmatism was statistically highly significant. The analysis of uncorrected visual acuity (UCVA) was statistically significant (P < 0.05) on postoperative day 1 and at 2, 4, and 12 postoperative weeks; it was statistically insignificant (P > 0.05) at postoperative week 8. Conclusion: Temporal incisions result in lesser postoperative surgically induced astigmatism (SIA) than superior incisions. Chevron incisions result in minimal change in corneal curvature. This effect can be utilized to tailor the postoperative astigmatism.

Comparison of surgically induced astigmatism in chevron, straight, and frown incisions in manual small-incision cataract surgery.

Purpose: : The study was conducted to calculate and compare the surgically induced astigmatism (SIA) in chevron, frown, and straight incisions in manual small-incision cataract surgery (MSICS). Methods: A prospective, hospital-based study was conducted on 90 patients aged 50 years and above with nuclear sclerosis of grade 4 or more. Each group had 30 patients, divided into Group V (chevron incision), Group S (straight incision), and Group F (frown incision). Patients who had with-the-rule (WTR) astigmatism were operated on through a chevron or straight incision superiorly, while patients who had against-the-rule (ATR) astigmatism underwent MSICS through a temporal frown incision. The patients were followed up post-operatively on days 1, 7, 6 weeks, and 12 weeks, and at each visit, the uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and SIA were calculated and compared. Results: The mean age of all the patients was 66.22 ± 8.05 years. BCVA of at least 6/18 or better at 12 weeks post-operatively was achieved in 29 patients (97%) in Group V, 28 patients (93%) in Group F, and 29 patients (97%) in Group S. The mean SIA in Group V was 0.34D ± 0.22D, in Group S was 0.97D ± 0.29D, and in Group F was 0.575D ± 0.25D. Conclusion: SIA by chevron incision is the least followed by the frown incision and straight incision. The superiorly placed chevron incision in WTR astigmatism provided optimal results for the best UCVA and minimal SIA. The temporal frown incision in ATR astigmatism also had good results.

Study of changes in pre-existing against-the-rule astigmatism after temporal manual small-incision cataract surgery using frown, straight, and smile incisions.

Purpose: To assess the change in the amount of astigmatism caused by frown, straight, and smile incision in patients with pre-existing against-the-rule (ATR) astigmatism of more than and equal to 1 diopter. Methods: This is a prospective, comparative study conducted over 18 months on 60 patients. Twenty patients were allocated to each incision using simple random sampling. Demographic details, best-corrected visual acuity (BCVA), intraocular pressure (IOP), anterior and posterior segment evaluation, and A-scan were done. An average of three measurements of K horizontal (Khavg), K vertical (Kvavg), and difference between the two (Khavg - Kvavg) were taken using manual keratometry. All surgeries were performed by a single surgeon. All the data analyses were performed by using IBM Statistical Package for the Social Sciences (SPSS) version 20 software. Frequency distribution and cross tabulation were performed to prepare the tables. Results: In frown incision, Khavg - Kvavg was significantly decreased on day 45 from the preoperative value (P < 0.001), followed by straight incision (P < 0.001), and smile incision (P < 0.001). Maximum decrease was observed in frown incision (49.15%) followed by straight (37.75%) and smile (28.57%) incisions. Conclusion: Our results are consistent with reduction of pre-existing ATR astigmatism with temporal incisions, and frown incision seems to be the best approach.

Re-inventing the straight incision with a single central suture in manual small-incision cataract surgery to minimize surgically induced astigmatism.

Purpose: To calculate the surgically induced astigmatism (SIA) in MSICS through a superiorly placed straight scleral incision closed with a single, central, perpendicular 10-0 polyamide suture and to document any suture-related complaints and complications. Methods: A retrospective, hospital-based study was carried out in 50 cases of uncomplicated senile cataract (>50 year) with nuclear sclerosis ≥ grade 4, "with the rule" astigmatism who underwent MSICS through a superior, straight incision with a single, central, perpendicular 10-0 nylon suture. Patients with "against the rule" astigmatism, keratoconus, pre-existing corneal opacity, astigmatism >2D, distorted or oblique mires, and previous ocular surgeries and unwilling to participate were excluded. Results: The mean age of the patients was 64.81 + 2.824 years, with a male: female ratio of 1.38:1. The mean SIA at day 7, week 6, and 12 weeks was 0.539 + 0.118, 0.529 + 0.134, and 0.524 + 0.129, respectively. Only 6 patients (12%) complained of foreign body sensation. No patient developed any suture-related complications. Conclusion: SIA is significantly reduced in straight incision by applying a single, central, and perpendicular 10-0 polyamide suture, as compared to a straight incision without a suture.

Comparative study between conventional and 4 mm manual small-incision cataract surgery.

Purpose: Comparative study of intraoperative and postoperative complications, visual outcomes, and cost-effectiveness between conventional and 4-mm manual small-incision cataract surgery with MVR blade. Methods: In total, 600 patients having nuclear sclerosis grade I-IV were operated under peribulbar anesthesia and were divided into two groups of 300 each. In group A (300), conventional small-incision cataract surgery was done, whereas in group B (300), 4-mm manual small-incision cataract surgery was performed through a 4-mm sclerocorneal tunnel. A wire vectis was passed through the 4-mm incision below the nucleus to stabilize it, and a 20-G MVR blade was introduced from 11o'clock limbus and nucleus was bisected into two halves, which were removed through main incision. Cortical wash was given, and foldable IOL was implanted. Intraoperative and postoperative complications between the two groups were compared. Postoperative visual outcome and surgically induced astigmatism between the two groups was studied. Results: The most common intraoperative complication was hyphema (11.33%) and irido-dialysis (8.00%), whereas postoperatively, striate keratopathy (36.33%) and hyphema (19.33%) were common. Short-term complications such as striate keratopathy, hyphema, and irido-dialysis were significantly more in group B, and long-term results in terms of visual outcome and surgically induced astigmatism were significantly less in group B. Conclusion: Although intraoperative and short-term postoperative complications were observed more in 4-mm manual small-incision cataract surgery, it was found to be more effective in terms of surgically induced astigmatism and final visual outcome. In addition, it is cost-effective as compared to phacoemulsification.

Evaluation of cautery in manual small-incision cataract surgery.

Purpose: Manual small-incision cataract surgery (MSICS) has a major role in tackling cataract blindness in our country. Cauterization of sclera is one of the important steps performed in MSICS to have bloodless field during surgery. Only few studies have addressed the effect of cautery on post-operative astigmatism. The present study is designed to evaluate the effect of cautery on surgically induced astigmatism in Indian patients. Methods: The study was designed as a prospective randomized trial conducted in a tertiary health care institution over a period of 2 years. A total of 150 eyes were randomized into two groups. The study group (Group 1, n = 75) underwent MSICS with cauterization using wetfield bipolar cautery with 4 amperes power. In the control group (Group 2, n = 75), no cauterization was performed. Surgically induced astigmatism was calculated using Naesers polar value method and compared between these two groups up to 60 days post-operatively. Results: Data from 150 eyes were available for evaluation. The net post-operative astigmatic value was 1.01 ± 0.21, 1.04 ± 0.19, and 1.03 ± 0.22 D on the 1^st, 7^th, and 30^th post-operative days, respectively, showing a stable trend in patients undergoing cauterization. In Group 2, the net post-operative astigmatic values observed were 0.47 ± 0.11 D, 0.54 ± 0.10, and 0.54 ± 0.09 D on the 1^st, 7^th, and 30^th post-operative days, respectively. The mean value of surgically induced astigmatism at 2 months post-operatively with and without cautery was 0.60 ± 0.20 D at 90° and 0.47 ± 0.10 D at 90°. The difference was not statistically significant (P = 0.08). Conclusion: The results of this study show that the use of cautery in MSICS is not associated with a higher surgically induced post-operative astigmatism. The magnitude of surgically induced astigmatism decreases with time.

Visual outcome after manual small-incision cataract surgery by viscoexpression technique.

Purpose: Globally, cataracts have remained the major cause of blindness. Cataract accounts for 62.6% of blindness affecting 9-12 million people. The only treatment for cataracts is surgical removal of cataracts. The surgical procedures include phacoemulsification and extracapsular cataract extraction (ECCE). In India, there is a huge backlog of cataract patients. Phacoemulsification is preferred nowadays for early visual rehabilitation, but in developing countries like ours, where facilities are not widely available, small-incision cataract surgery (SICS) is a cost-effective alternative as no machine is required. Also, it provides early visual rehabilitation as it is sutureless when compared to ECCE. So, manual SICS has emerged as a substitute for phacoemulsification and ECCE. The aim of the study was to evaluate the visual acuity and surgically induced astigmatism in patients more than 40 years of age, undergoing manual SICS with nucleus management by viscoexpression technique. Methods: This was a prospective study that included 50 patients over the age of 40 years undergoing manual SICS at a tertiary health-care center in North India by viscoexpression technique. Only those patients whose functional visual disability could be attributed to cataracts were included in the study. Preoperative and postoperative astigmatism were analyzed in the first, fourth, and sixth weeks. Results: Fifty patients who were undergoing manual SICS were analyzed. Preoperative best-corrected visual acuity (BCVA) and astigmatism were compared to postoperative BCVA and astigmatism. Of 50 patients, 48 (96%) patients were able to gain good vision after 6 weeks. Conclusion: This study showed early visual rehabilitation with less surgically induced astigmatism following manual SICS by viscoexpression technique.

Regular and irregular astigmatism of bullous keratopathy using Fourier harmonic analysis with anterior segment optical coherence tomography.

Bullous keratopathy (BK) is known to present with corneal edema and Descemet's folds, which can cause corneal astigmatism. However, no report quantitatively evaluated BK astigmatism by separating it into regular and irregular astigmatism. This study investigated the regular and irregular astigmatism of the anterior and posterior corneal surface with Fourier harmonic analysis and anterior segment optical coherence tomography. Preoperative data from 43 eyes of 41 BK patients who received corneal endothelial transplantation were compared with the data from 43 eyes of 43 subjects without corneal disease. Anterior and posterior cylinder power, central corneal thickness (CCT) and thinnest corneal thickness were significantly greater in BK. With Fourier harmonic analysis, BK eyes were found to have significantly larger anterior and posterior regular astigmatism, asymmetry component and higher-order irregularity. Asymmetry component and higher-order irregularity that accounted for the posterior irregular astigmatism increased as CCT increased in BK. Higher-order irregularity in the posterior cornea also positively correlated with worsening best corrected visual acuity. Subgroup analysis found significant correlations between CCT and posterior higher-order irregularity for intraocular surgery and laser iridotomy, but not Fuchs endothelial corneal dystrophy. This study has significance in that it revealed the characteristics of the corneal posterior irregular astigmatism of BK.

DETERMINATION OF FACTORS ASSOCIATED WITH LONG-TERM ENDOTHELIAL LOSS AND REFRACTIVE RESULT IN PATIENTS WITH ARTISAN PHAKIC LENS.

PURPOSE: To determine the changes in endothelial cell density, refractive results, and risk factors associated with endothelial loss in patients with irisclaw phakic intraocular lenses for myopia/myopic astigmatism (Artisan). METHODOLOGY: Data collection was obtained from an existing database with information on patients with a phakic Artisan lens implant between 1998 and 2011 at the Virgilio Galvis Ophthalmology Centre, with at least 5 years of follow-up. As a second stage, an analysis was carried out to identify the change in endothelial cell density and its potential associated factors. RESULTS: A total of 80 eyes with myopic errors were included with a follow-up of 11.9 + 3.48 years. The percentage of total loss of endothelial cells was greater than 25% of the preoperative density in 43.8% of the eyes. A postoperative annual loss > 1.6% was found in 47.0% of the eyes with that information available. 41 eyes (51%) had final endothelial density < 2000 cells/mm2, and 7 (8.8%) eyes had endothelial cell density < 1000 cells/mm2. Among the variables studied, no associated factors for long-term endothelial loss were found. During the course of the study, 8 (10%) phakic intraocular lenses were explanted, including 3 with accelerated endothelial loss, and another 2 with cataract associated and a significantly low endothelial density. The last mean spherical equivalent was -0.81 (±1.01 D), and the final uncorrected distance visual acuity was 0.45 logMar (Snellen 20/56). CONCLUSION: Artisan-type phakic lenses are a good alternative for the correction of high myopic defects, with predictable refractive results in the long term. However, there is an increased loss of endothelial cells in the long term in a high percentage of patients. Strict postoperative follow-up, including endothelial evaluation, is required, and further studies are warranted.

Analysis of the Changes and Possible Reasons in Aberrations before and after Surgery in Patients with Concomitant Exotropia.

Objective: The objective is to observe the changes in aberrations before and after surgery in patients with common horizontal strabismus and to analyze the possible reasons for the changes. Methods: Forty eyes of 40 cases with concomitant exotropia who underwent strabismus correction at the Ophthalmology Department of Nantong University Hospital from October 2020 to July 2021 were included in this study, all of whom underwent unilateral lateral rectus recession combined with a medial rectus resection in the same eye. Aberration parameters were measured 1 day before surgery and 1 week, 1 month, 3 months, and 6 months after surgery. Differences in the indicators at each time period were compared by analysis of variance (ANOVA) of repeated measures data for a single factor, and data were analyzed using SPSS 25.0 statistical application software. Results: 5 mm pupil diameter: the preoperative and postoperative RMS of total aberration showed statistically significant difference (P < 0.01). Postoperation test (Bonferroni method) and preoperative comparison at each period after surgery showed statistically significant differences between 6 months after surgery (P=0.002) and preoperative comparison. The preoperative and postoperative comparison of RMS in LOAs was statistically significant (P < 0.01); postoperative test (Bonferroni method) and preoperative comparison showed that there were statistically significant differences between 1 week (P=0.033) and 6 months (P=0.002) after operation. The difference of RMS of defocus before and after operation was statistically significant (P < 0.01); postoperation test (Bonferroni method) and preoperative comparison showed that there was statistically significant difference between 6 months after operation (P=0.007) and preoperative comparison. There was statistically significant difference in preoperative and postoperative RMS of HOAs (P=0.013). Postoperative test (Bonferroni method) and preoperative comparison showed that there was statistically significant difference 6 months after surgery (P=0.03). The RMS of secondary astigmatism showed a statistically significant difference before and after operation (P=0.001), and the postoperation test (Bonferroni method) showed a statistically significant difference 6 months after operation (P=0.002). In 5 mm pupil diameter, the preoperative and postoperative RMS of total aberration showed statistically significant difference (P < 0.01), postoperative test (Bonferroni method) was used to compare each period after surgery with that before surgery, and there were statistically significant differences between 1 week after surgery (P=0.034), 3 months after surgery (P=0.033), and 6 months after surgery (P=0.003). The preoperative and postoperative comparison of RMS in LOAs was statistically significant (P < 0.01), postoperative test (Bonferroni method) was used to compare each period after surgery with that before surgery, and there were statistically significant differences between 1 week after surgery (P=0.04), 3 months after surgery (P=0.034), and 6 months after surgery (P=0.004). The difference of RMS of defocus before and after surgery was statistically significant (P=0.002), and the comparison between postoperation test (Bonferroni method) and preoperation showed that the difference was statistically significant 6 months after surgery (P=0.027). The RMS of astigmatism showed statistically significant difference before and after operation (P=0.002), and the postoperation test (Bonferroni method) showed statistically significant difference between 6 months after operation (P=0.009) and before operation. Conclusion: We found that horizontal rectus surgery had a transient effect on LOAs and almost no effect on HOAs. Long-term follow-up is recommended after strabismus surgery to observe eye position and binocular visual function. Because of the high prevalence of strabismus in adolescents, long-term observation of the eye axis and aberration is recommended.

Comparison of Ocular Biometric Parameters Between Hispanic and Non-Hispanic Ethnicities in White Adults Undergoing Cataract Surgery.

OBJECTIVES: To compare ocular biometric parameters between Hispanic and non-Hispanic White adult patients undergoing cataract surgery. METHODS: We included 433 adult patients undergoing surgery for senile cataract. Only patients with race and ethnicities of Hispanic and non-Hispanic White were included. The following parameters measured by the IOLMaster 700 were compared between Hispanic and non-Hispanic patients: mean keratometry, corneal astigmatism, anterior chamber depth (ACD), lens thickness, vitreous length, axial length, white-to-white diameter, and emmetropic intraocular lens power. RESULTS: There were 219 Hispanic patients and 214 non-Hispanic patients with a mean age of 70.1±7.7 years (range, 50-88 years), and 66.7% were women. Although sex distribution was similar between the two groups, Hispanic patients had a lower age compared with non-Hispanic patients (69.3±8.3 vs. 70.9±6.9 years, P=0.02). In biometric values, ACD was significantly lower in Hispanic patients (3.07±0.40 mm) than in non-Hispanic patients (3.16±0.37 mm, P=0.01). Such statistically significant difference persisted after adjustment for age and sex (P=0.01). No other significant differences were found in other ocular parameters measured. CONCLUSIONS: Anterior chamber depth is significantly shorter in Hispanic patients compared with non-Hispanic patients. Such ethnic difference should be considered when performing cataract and corneal surgeries because this ethnic difference may be associated with a higher risk of corneal endothelial injury.