Optical coherence tomography angiography parameters after cataract surgery.

PURPOSE: To evaluate the changes in macular blood flow after cataract surgery through optical coherence tomography angiography (OCT-A). METHODS: In this prospective case series, 50 patients who underwent uncomplicated cataract surgery by the resident were included. OCT-A images and complete ocular examinations were performed at baseline, 1 and 3 months postoperatively. The changes in OCT-A parameters including foveal avascular zone (FAZ) area, vessel density (VD) of superficial and deep plexus, and central macular thickness were assessed before and after surgery. Cataract grading, intraocular inflammation, and duration of surgery were analyzed. RESULTS: FAZ was significantly reduced from 0.36 ± 0.13 mm2 at baseline to 0.32 ± 0.12 mm2 at month 1 (P < 0.001) and this reduction continued until month 3. In the superficial layer, vessel density of the fovea, parafovea, and whole image significantly increased from 13.9 ± 6.8, 43.7 ± 4.7, and 43.2 ± 4.4 at baseline to 18.4 ± 7.9, 45.7 ± 4.9, and 44.9 ± 4.5 at month 1. The increase in the vessel density of the deep layer was similar to the superficial layer. Accordingly, CMT at the fovea was significantly increased from 240.5 ± 21.99 µm at baseline to 253.1 ± 23.2 microns at month 1 (P < 0.001) and the increase significantly continued and reached 259.5 ± 22.6 µm at month 3 (P < 0.001). Accordingly, the FAZ area significantly reduced one month postoperatively. In regression analysis, CMT changes positively correlated with cataract grading. FAZ area negatively correlated with intraocular inflammation on the first postoperative day. CONCLUSION: The present study shows that CMT and vessel density of the macula significantly increase after uncomplicated cataract surgery, while the FAZ area reduces. Postoperative inflammation could be the possible explanation for the findings of this study.

Association of Patient Satisfaction with Cataract Grading in Five Types of Multifocal IOLs.

INTRODUCTION: This study investigated patient satisfaction levels in five premium intraocular lenses (IOLs). A secondary aim was to determine whether patient satisfaction was associated with the cataract grade before lens surgery. METHODS: In this multicenter prospective comparative study, 164 patients from diverse backgrounds underwent cataract surgery and were assigned for identical bilateral implantation of multifocal IOLs. In addition to visual performance, quality of life was measured using the National Eye Institute Refractive Error Quality Of Life Instrument (NEI-RQL 42) scoring questionnaire. The Sirius Scheimpflug Analyzer was used to evaluate the posterior cornea and aberrations. Finally, the association of patient satisfaction reports with the Pentacam Cataract Grading Scale (PCGS) and Lens Opacities Classification System (LOCS III) was evaluated. RESULTS: A considerable subjective improvement was observed in uncorrected far, near (40 cm), and intermediate (60 cm) visual acuity in the five groups (P values < 0.001). A significant difference was observed in mesopic and photopic contrast sensitivity between Symfony, Trinova, and AT LISA at the spatial frequency of 12 cycles per degree, favoring Symfony (P < 0.001). PanOptix users had considerably lower mean coma values (P < 0.001), while AT LISA users had lower mean spherical aberrations (P = 0.009) compared to the other groups. No additional safety concerns relating to IOLs were recorded. Mean satisfaction had a high correlation with LOCS and Pentacam Nuclear Staging (PNS) in each lens group, e.g., correlation coefficient and P value for AT LISA were respectively r = 0.99, P < 0.001 and r = 0.97, P = 0.004. CONCLUSION: Despite discrepancies between groups of lenses, most patients who received multifocal IOLs reported satisfaction at more than 3 years after the initial operation. A growing number of patients with cataracts are seeking spectacle-free vision with presbyopia-correcting IOLs. Hence, the high satisfaction rate among patients with cataract could indicate the value of offering a wider range of available lenses.

Central anterior chamber depth changes after prophylactic laser iridotomy.

PURPOSE: To evaluate the effect of laser peripheral iridotomy (LPI) on biometric parameters including central anterior chamber depth (CACD) in primary angle closure suspect eyes. METHODS: Eyes classified as primary angle closure suspect were enrolled in this interventional case series. Biometry with Lenstar (Haag-Streit AG, Koeniz, Switzerland) was performed before LPI and 6 weeks afterward. Central anterior chamber depth, lens thickness, axial length, and central corneal thickness were measured before and after the intervention. RESULTS: Forty eyes of 40 patients with mean age of 56.5 ± 5.5 years were studied. Mean central anterior chamber depth was 2.07 ± 0.21 mm before and 2.08 ± 0.19 mm after LPI (p = 0.8). There was no significant change in lens thickness, axial length, and central corneal thickness after LPI. CONCLUSIONS: Central anterior chamber depth "measured by Lenstar" does not change after LPI in primary angle closure suspect eyes.

Clinical Outcomes of Femtosecond Laser-assisted Implantation of 325-Degree Versus 340-Degree Arc Length Intracorneal Ring Segments in Naive Keratoconic Eyes.

Purpose: To evaluate and compare clinical outcomes after femtosecond laser-assisted implantation of 325-degree versus 340-degree arc length intracorneal ring segments (ICRS) in eyes with keratoconus (KCN). Methods: In this prospective non-randomized interventional case series, 23 eyes of 21 patients diagnosed with KCN, underwent femtosecond laser-assisted implantation of two types of ICRS, which included a 325-degree ICRS (Group 325) and a 340-degree ICRS (Group 340). The primary outcome measures were uncorrected distance visual acuity (UDVA), and the secondary outcome measures included corrected distance visual acuity (CDVA), sphere, cylinder, mean refractive spherical equivalent (MRSE), keratometry, vectorial change in corneal astigmatism, and the location of maximum keratometry relative to the corneal apex. The study groups were compared using the primary and secondary outcome measures obtained at postoperative months six and 12. Results: Groups 325 and 340 consisted of 10 and 13 eyes, respectively. The two groups were comparable in terms of parameters measured preoperatively. On comparison to the baseline values, both study groups exhibited a significant increase in UDVA and CDVA measured at postoperative month six (Ps < 0.05) and a significant decrease in the sphere, cylinder, spherical equivalent refraction, and keratometry readings measured at postoperative months six and 12 (Ps < 0.05). No significant differences were observed between the two groups in terms of visual, refractive, and keratometric outcomes at any time point. No intraoperative or postoperative complications were observed in any of the study groups. Conclusion: Both the 325-degree ICRS and the 340-degree ICRS effectively and equally improved visual, refractive, and keratometric outcomes in keratoconic eyes.

Comparison of corneal tomography measurements using Galilei, Orbscan II, and Placido disk-based topographer systems.

PURPOSE: To evaluate agreement in keratometry readings and anterior and posterior elevation map measurements among the Galilei V4.01 (Ziemer), Orbscan IIz (Bausch & Lomb), and Corneal Map topographer (Costruzione Strumenti Oftalmici) systems. METHODS: This prospective comparative study comprised 184 eyes of 92 consecutive refractive surgery candidates who were simultaneously examined with the Galilei (dual Scheimpflug), Orbscan II (scanning-slit), and Corneal Map topographer (Placido disk-based) systems. Keratometry readings and anterior and posterior elevation map measurements were compared using analysis of variance and paired t test, respectively. RESULTS: Mean keratometry reading was 44.30 ± 1.49 diopters (D), 44.11 ± 1.47 D, and 44.60 ± 1.56 D with the Galilei, Orbscan, and Corneal Map topographer, respectively. Despite a significant difference in mean keratometry (P<.001), the correlation among these three systems was strong. The maximum mean difference between two sets in simulated keratometry and astigmatism was <0.50 D. In the evaluation of anterior best-fit-sphere (BFS) and posterior BFS, the correlation between Galilei and Orbscan II was found to be 0.960 and 0.947, respectively. Maximum anterior central elevation measured by Orbscan II and Galilei was 9.2 ± 5.1 µm and 3.2 ± 1.8 µm, respectively. Maximum posterior central elevation by Orbscan II and Galilei was 33.8 ± 9.3 µm and 6.8 ± 3.8 µm, respectively. CONCLUSIONS: Despite significant differences in mean keratometry readings and anterior and posterior elevation measurements among the three systems, the keratometry readings can be used interchangeably, as this difference is not clinically significant.

Systemic supplemental oxygen therapy during accelerated corneal crosslinking for progressive keratoconus: randomized clinical trial.

PURPOSE: To investigate the potential additive effect of systemic supplemental oxygen administered during accelerated corneal crosslinking (CXL) for progressive keratoconus (KC). SETTING: Academic center. DESIGN: Randomized clinical trial. METHODS: Eyes with progressive KC randomized to 3 different CXL protocols were included. The first group (OA-CXL) included 19 eyes that underwent an accelerated CXL protocol (9 mW/cm2 for 10 minutes) while receiving systemic oxygen at a rate of 5 L/min for 10 minutes. The second group consisted of 14 eyes undergoing the same accelerated CXL protocol without supplemental oxygen therapy (A-CXL). The third group (C-CXL) comprised 14 eyes undergoing conventional CXL according to the Dresden protocol. All subjects were followed up for at least 6 months. Visual acuity, keratometry and corneal biomechanical parameters including corneal hysteresis and corneal resistance factor (CRF) were measured preoperatively and 6 months postoperatively. RESULTS: Reduction in maximum keratometry (Kmax) was significantly greater in the OA-CXL group (P = .01). At baseline, the mean Kmax was 54.31 ± 3.64 diopters (D) in the OA-CXL group, 54.66 ± 4.99 D in the A-CXL group, and 56.03 ± 5.28 D in the C-CXL group (P = .58), which reached 53.58 ± 3.24 D, 54.59 ± 4.65 D, and 55.87 ± 4.73 D at 6 months in the 3 study groups, respectively (P = .115). The mean CRF increased significantly only in the OA-CXL group from a baseline value of 6.32 ± 2.12 mm Hg to 7.38 ± 1.88 mm Hg at 6 months (P = .009). CONCLUSIONS: This study suggests superior efficacy of an accelerated CXL protocol coupled with systemic oxygen supplementation when compared with the accelerated CXL protocol and the conventional protocol in eyes with progressive KC. In addition to greater reduction in Kmax as the primary outcome, improvement in corneal biomechanics was also observed at 6 months.

Topical 0.03% tacrolimus versus systemic mycophenolate mofetil as adjuncts to systemic corticosteroids for preventing graft rejection after repeat keratoplasty: one-year results of a randomized clinical trial.

PURPOSE: To compare the efficacy of topical 0.03% tacrolimus in combination with systemic corticosteroids versus systemic mycophenolate mofetil (MMF) and corticosteroids in preventing corneal allograft rejection after repeat keratoplasty. METHODS: This prospective, randomized clinical trial enrolled 63 consecutive eyes of 63 patients who underwent repeat keratoplasty after a failed penetrating keratoplasty. Group 1 (32 eyes) received MMF orally 1 g twice daily for the first 6 months and then 1 g daily for the next 6 months, and group 2 (31 eyes) received topical 0.03% tacrolimus four times a day for 12 months. All patients were treated with topical and oral corticosteroids postoperatively. The participants were observed closely for signs of graft rejection, and the rates of rejection-free graft survival were calculated and compared between the two groups at postoperative month 12. RESULTS: The groups were balanced in patient's age and risk factors for graft rejection (e.g., original diagnosis, number of previous grafts, and quadrants of corneal vascularization). Endothelial graft rejection occurred in 5 eyes (15.6%) of group 1 and 6 eyes (19.4%) of group 2 (P = 0.75). Irreversible endothelial graft rejection resulting in graft failure occurred in 3 eyes of each group (P = 0.99). The rate of rejection-free graft survival was 84.4% in group 1 and 80.6% in group 2 at postoperative month 12 (P = 0.74). CONCLUSION: Topical 0.03% tacrolimus was as effective as systemic MMF as adjuncts to topical and systemic corticosteroids in reducing endothelial graft rejection with 12 months follow up after repeat keratoplasty.

Trans-iris fixation of dislocated in-the-bag intraocular lenses.

PURPOSE: The aim of this article is to describe the safety and efficacy of trans-iris suture fixation for the management of late dislocation of in-the-capsular-bag intraocular lenses following uncomplicated cataract surgery. PATIENTS AND METHODS: Eleven eyes of 11 patients with late in-the-capsular-bag intraocular lens dislocation following uneventful phacoemulsification cataract surgery were recruited in the study. The dislocated intraocular lens-capsular bag complex was sutured to the iris at two points 180° apart using 9-0 polypropylene sutures on long needles. RESULTS: Mean patient age was 67 ± 6 years. Seven eyes had pseudoexfoliation syndrome, one eye had Marfan syndrome, and another eye had a traumatic cataract; no risk factor was identified for intraocular lens dislocation in two eyes. A capsular tension ring had been implanted during cataract surgery in four eyes. In six eyes, the posterior chamber intraocular lenses were one-piece foldable while the remaining were three-piece intraocular lenses. Compared to the preoperative value, corrected distance visual acuity was significantly improved postoperatively (p < 0.005). Intraoperative hyphema occurred in two eyes. Pupil ovalization was observed in all eyes. Mean endothelial cell count decreased by 4 ± 1.7% after intraocular lens fixation. The capsular bag-intraocular lens complex was stable and well-centered in the pupillary area in all eyes at the final follow-up examination which was performed 16 ± 4 months postoperatively. CONCLUSION: Trans-iris fixation is a simple and effective procedure for management of late intraocular lenses-capsular bag complex dislocation, without major complications.

Lower- and higher-order aberrations after photorefractive keratectomy with and without compensation of pupil centroid shift: fellow eye comparison.

PURPOSE: To study the effect of pupil centroid shift (PCS) compensation on lower- and higher-order aberrations (HOAs) after photorefractive keratectomy (PRK). SETTING: Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. DESIGN: Prospective intrasubject fellow eye study. METHODS: One hundred twelve eyes of 56 patients with simple myopia or myopic astigmatism scheduled for PRK were enrolled. Preoperatively, the amount of PCS was measured in the horizontal and vertical directions. All eyes received wavefront-optimized treatment with static cyclotorsion compensation. PCS compensation was turned on for the right eye of each subject (PCS-on group), and turned off for the left eye (PCS-off group). Postoperatively, refraction and corneal HOAs were compared between the study groups at 6 months. RESULTS: Mean preoperative myopia was -3.84 diopters (D) ± 2.41 (SD) vs -3.75 ± 2.27 D (P = .408), whereas mean preoperative cylinder was -1.18 D ± 1.15 (SD) vs -1.14 ± 1.16 D (P = .769) in the PCS-on and PCS-off groups, respectively. Mean absolute PCS values were 62.25 µm ± 41.82 (SD) vs 55.92 ± 37.47 µm (P = .45) in the horizontal direction and 65.04 ± 47.16 µm vs 58.40 ± 45.44 µm in the vertical direction (P = .29) in the PCS-on and PCS-off groups, respectively. The study groups were comparable in terms of postoperative refraction and root mean square of total corneal HOAs. CONCLUSIONS: Compensation of PCS did not affect lower- and higher-order aberrations after wavefront-optimized PRK with static cyclotorsion compensation in myopic or myopic astigmatic eyes.

Topical Umbilical Cord Serum for Corneal Epithelial Defects after Diabetic Vitrectomy.

PURPOSE: To evaluate the role of topical umbilical cord serum (TUCS) therapy in treating corneal epithelial defects (CEDs) after diabetic vitrectomy. METHODS: In this double-masked, randomized clinical trial, we included 80 eyes of 80 patients who were candidates for vitrectomy due to proliferative diabetic retinopathy complications. In cases of corneal edema obscuring the fundus view during surgery, the corneal epithelium was removed using a 6-mm trephine and a blade no.15. The day after the surgery, patients were randomly divided into two groups: (1) the TUCS group that received 20% TUCS six times/day in addition to the conventional treatment of CED and (2) the control group, which was prescribed artificial tears as placebo in addition to the conventional treatment of CED. The rate of healing of CEDs was measured via two maximum linear dimensions perpendicular to each other at the start of therapy and on postoperative days 1-5, 7, and 12. RESULTS: Of 80 eyes, 40 were assigned to each treatment group. The mean times to complete CED healing were 2.4 ± 0.7 and 3.8 ± 2.1 days in the TUCS and control groups, respectively (P < 0.001). Persistent CED occurred in two eyes in the control group but in no eyes in the TUCS group. CONCLUSION: TUCS therapy may be safe and effective in healing CEDs after vitrectomy in patients with diabetes.

Recurrent Peripheral Stromal Keratitis Following Corneal Collagen Cross-linking: A Case Report.

PURPOSE: Corneal collagen cross-linking (CXL) has become the standard initial intervention in eyes with progressive keratoconus (KC) that have not undergone keratoplasty. The prolonged exposure of the de-epithelialized cornea predisposes it to adverse complications, such as microbial keratitis and melting. Herein, we report a case of bilateral recurrent peripheral stromal keratitis following CXL. CASE REPORT: We present a 29-year-old woman who complained of ocular redness and discomfort in both eyes for 4 months, and had undergone bilateral CXL 10 months before. The best spectacle corrected visual acuity (BSCVA) was 60/200 in the right and 80/200 in the left eye. Both eyes showed moderate conjunctival hyperemia, dilation, and engorgement of the perilimbal episcleral vessels. There was a peripheral corneal stromal infiltration with thinning, and an overlying epithelial defect in the right eye with a lucid interval from the limbus. She was treated with lubricating eye drops and ointments and topical corticosteroids every 4 hours for 2 weeks then slowly tapered off. Afterwards, she experienced multiple recurrences in both eyes, which were successfully managed with topical corticosteroids and lubricants. After 2 years, her BSCVA was 20/30 with -3.00-5.50 * 90 in the right eye and 20/40 with -4.00-4.50 * 90 in the left. CONCLUSION: Although CXL is a safe method, studies with longer follow-ups are needed to investigate the risk of rare complications.

Goldmann applanation tonometer versus ocular response analyzer for measuring intraocular pressure after congenital cataract surgery.

PURPOSE: To compare intraocular pressure measured using the Goldmann applanation tonometer with that measured using the ocular response analyzer after congenital cataract surgery. METHODS: This study included 113 eyes of 64 patients who underwent lensectomy and vitrectomy. In all, 36 eyes remained aphakic after surgery. Intraocular lens implantation was performed at the time of surgery in 47 eyes and secondarily in 30 eyes. Corneal hysteresis, corneal resistance factor, and cornea-compensated intraocular pressure were measured. The influences of independent factors on the difference between the cornea-compensated intraocular pressure and intraocular pressure measured with Goldmann applanation tonometer were investigated using linear regression analyses. Agreement between the two tonometers was investigated using the Bland and Altman and 95% limits of agreement analysis. RESULTS: Central corneal thickness, corneal hysteresis, and corneal resistance factor were 591.2 ± 53.3 µm, 10.83 ± 2.27 mmHg, and 11.36 ± 2.14 mmHg, respectively. Cornea-compensated intraocular pressure (16.75 ± 4.82 mmHg) was significantly higher than intraocular pressure measured with Goldmann applanation tonometer (14.41 ± 2.27 mmHg, p < 0.001). Central corneal thickness (p = 0.02) and corneal hysteresis (p < 0.001) were identified as the main predictors of difference between cornea-compensated intraocular pressure and intraocular pressure measured with Goldmann applanation tonometer readings. A 95% limits of agreement for cornea-compensated intraocular pressure and intraocular pressure measured with Goldmann applanation tonometer was between -4.86 and 9.53 mmHg in the entire group. Cornea-compensated intraocular pressure showed the best agreement with intraocular pressure measured with Goldmann applanation tonometer in the primary pseudophakic subgroup as compared to the other subgroups. CONCLUSION: The Goldmann applanation tonometer and ocular response analyzer cannot be used interchangeably for measuring intraocular pressure after congenital cataract surgery. The difference between the cornea-compensated intraocular pressure and intraocular pressure measured with Goldmann applanation tonometer was primarily affected by central corneal thickness and corneal hysteresis. Among the subgroups, the primary pseudophakic subgroup had the thinnest cornea and the highest corneal hysteresis values and demonstrated the best agreement between the two tonometers.

Goldmann Applanation Tonometer Versus Ocular Response Analyzer for Measuring Intraocular Pressure After Descemet Stripping Automated Endothelial Keratoplasty.

PURPOSE: To evaluate agreement between IOP measured using the ocular response analyzer (ORA) versus using the Goldmann applanation tonometer (GAT) in patients treated by Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: This prospective, case-control study comprised 38 normal eyes and 37 post-DSAEK eyes. IOP was measured using the GAT (IOPGAT). The ORA was used to measure corneal biomechanics and cornea-compensated IOP (IOPCC). Corneal hysteresis (CH), corneal resistance factor, and IOP measurements of the 2 groups were compared. Intertonometer agreement was evaluated in each study group using Bland-Altman plots and 95% limits of agreement. Univariate analysis was used to evaluate the effect of independent factors on the difference between the 2 IOP readings (ΔIOP). RESULTS: The IOPCC and IOPGAT readings showed no significant intergroup differences. IOPCC was significantly higher than IOPGAT, with a mean difference of 3.0 ± 3.3 mm Hg in the normal group (P < 0.001) and 4.5 ± 3.1 mm Hg in the DSAEK group (P < 0.001). The 95% limits of agreement for the IOPCC and IOPGAT was between -3.4 and 9.5 mm Hg and between -1.6 and 10.6 mm Hg in the normal and DSAEK groups, respectively. CH (r = -0.57, P < 0.001) and donor thickness (r = 0.81, P = 0.04) were identified as the main predictors of ΔIOP after DSAEK. ΔIOP did not vary significantly with the central corneal thickness or corneal resistance factor. CONCLUSIONS: The IOPGAT and IOPCC were significantly different, which indicates that the GAT and ORA cannot be used interchangeably for measuring IOP after DSAEK. The difference between these 2 measurements was primarily affected by the variations in CH and donor thickness.

Effect of Cycloplegia on Corneal Biometrics and Refractive State.

PURPOSE: To determine changes in refractive state and corneal parameters after cycloplegia with cyclopentolate hydrochloride 1% using a dual Scheimpflug imaging system. METHODS: In this prospective cross-sectional study patients aged 10 to 40 years who were referred for optometric evaluation enrolled and underwent autorefraction and corneal imaging with the Galilei dual Scheimpflug system before and 30 minutes after twice instillation of medication. Changes in refraction and astigmatism were investigated. Corneal biometrics including anterior and posterior corneal curvatures, total corneal power and corneal pachymetry were compared before and after cycloplegia. RESULTS: Two hundred and twelve eyes of 106 subjects with mean age of 28 ± 5 years including 201 myopic and 11 hyperopic eyes were evaluated. Mean spherical equivalent refractive error before cycloplegia was -3.4 ± 2.6 D. A mean hyperopic shift of 0.4 ± 0.5 D occurred after cycloplegia (P < 0.001). The astigmatism power did not significantly change (P = 0.8), however, 26.8% of eyes with significant astigmatism experienced a change of more than 5 degrees in the axis of astigmatism. Changes in posterior corneal curvature were scant but statistically significant (P = 0.001). Moreover, corneal thickness was slightly increased in the central and paracentral regions (P < 0.001 and P < 0.001, respectively). CONCLUSION: Cycloplegia causes a hyperopic shift and astigmatism axis changes, along with an increase in central and paracentral corneal thickness and change in posterior corneal curvature. The effects of cycloplegia on refraction and corneal biometrics should be considered before cataract and refractive surgeries.

Accuracy of Various Intraocular Lens Power Calculation Formulas in Steep Corneas.

PURPOSE: To compare the accuracy of four different intraocular lens (IOL) power calculation formulas for eyes with mean keratometry values greater than 46 diopters (D). METHODS: Forty five eyes from 45 patients who were candidates for senile cataract surgery with mean keratometry values greater than 46 D were included. Calculation of the IOL power was performed by the Lenstar. The implanted IOL in all cases was Acrysof SA60AT. The average absolute value of the differences between the actual and predicted spherical equivalent (SE) of the postoperative refractive error (mean absolute error: MAE) was calculated using 4 formulas (Haigis, Holladay 1, Hoffer Q, and SRK/T) with optical IOL constants from the User Group for Laser Interference Biometry constants. RESULTS: The MAE was smallest in the SRK/T formula (0.39 D ± 0.35) followed by those of the Holladay 1 (0.44 D ± 0.32), Haigis (0.45 D ± 0.35) and Hoffer Q (0.5 D ± 0.38) formulas. However, there was no statistically significant difference between the MAE among different formulas. The SRK/T formula predicted more eyes within ± 0.5 D of the SE (77.8%) compared to other formulas. CONCLUSION: In eyes with steep corneas, there were no statistically significant differences among the accuracies of the four common IOL power calculation formulas.

Factors influencing intraocular pressure, corneal thickness and corneal biomechanics after congenital cataract surgery.

AIMS: This study aims to compare intraocular pressure (IOP), central corneal thickness (CCT) and corneal biomechanics among patients with aphakia, patients with primary and secondary pseudophakia and matched controls following congenital cataract surgery and to investigate the factors influencing these variables. METHODS: This study included 36 aphakic eyes, 47 primary pseudophakic eyes and 30 secondary pseudophakic eyes. Thirty-four normal eyes of matched volunteers were recruited for comparisons. Postoperative IOP measured with a Goldmann applanation tonometer (IOPGAT), CCT, corneal hysteresis (CH), corneal resistance factor (CRF) and cornea-compensated IOP (IOPCC) were compared among the groups. Univariate analyses and multiple linear regression analyses were used to investigate the influences of independent factors on IOPGAT, CCT, CH, CRF and IOPCC, considering all the operated eyes as one group. RESULTS: IOPGAT was 12.5±0.92, 14.7±1.9, 13.4±2.3 and 15.7±2.0 mm Hg in normal, aphakic, primary pseudophakic and secondary pseudophakic eyes, respectively (p<0.001). CCT was 559.5±42.7, 628.0±61.7, 566.8±35.3 and 585.2±41.1 µm, respectively (p<0.001). CH was 10.87±2.47, 10.42±2.20, 11.84±2.13 and 9.74±1.94 mm Hg, respectively (p=0.019). IOPCC was 15.91±3.74, 18.40±4.35, 14.58±4.36 and 19.05±4.54 mm Hg, respectively (p<0.001). There was no significant difference in CRF among the groups (p=0.06). Regression analyses revealed that the type of operation was significantly associated with IOPGAT (p=0.04), CCT (p<0.001) and CH (p=0.006). CONCLUSIONS: IOPGAT, CCT, CH and IOPCC were significantly different in treated eyes compared with normal eyes after congenital cataract surgery. These variables were primarily affected by the type of surgery. Primary intraocular lens implantation preserved corneal structure and function of the anterior chamber angle.

Aspheric versus wavefront-guided aspheric photorefractive keratectomy in eyes with significant astigmatism.

PURPOSE: To compare the refractive and higher-order aberrations (HOAs) outcomes after photorefractive keratectomy (PRK) in patients with significant astigmatism using aspheric versus wavefront-guided aspheric profiles. SETTING: Ophthalmic Research Center and Department of Ophthalmology, Shahid Beheshti University of Medical Sciences, Negah Eye Hospital, Tehran, Iran. DESIGN: Prospective randomized case series. METHODS: One eye of each patient with a refractive astigmatism more than 2.00 diopters (D) randomly received aspheric PRK. In the other eye, wavefront-guided and aspheric treatment was performed using a personalized treatment advanced algorithm. Visual acuity, refractive errors, and HOAs were compared between the 2 groups preoperatively and 12 months postoperatively. RESULTS: The study comprised 32 patients (64 eyes). The mean preoperative refractive astigmatism was -4.07 D ± 1.64 (SD) and -4.02 ± 1.55 D in the aspheric group and wavefront-guided aspheric group, respectively (P = .2). The mean postoperative astigmatism was -0.46 ± 0.37 D and -0.82 ± 0.53 D in the aspheric group and wavefront-guided aspheric group, respectively (P = .02). Postoperatively, the root mean square of total HOAs was significantly increased in both groups. However, compared with wavefront-guided aspheric PRK, aspheric PRK induced fewer HOAs (P = .003). CONCLUSIONS: In eyes with high astigmatism, post-PRK residual astigmatism was lower in the aspheric group than in the wavefront-guided aspheric group. The increase in HOAs was significantly higher in the wavefront-guided aspheric group than in the aspheric group.

Comparison of Loteprednol with Fluorometholone after Myopic Photorefractive Keratectomy.

PURPOSE: To compare the efficacy and side effects of loteprednol versus fluorometholone after myopic photorefractive keratectomy (PRK). METHODS: One hundred and twenty four eyes of 62 patients who underwent PRK were enrolled in this study. One eye of each subject was randomized to receive loteprednol 0.5% and the fellow eye was given fluorometholone 0.1%. Patients were followed up for three months. RESULTS: There was no significant difference in uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, corneal haze, intraocular pressure (IOP), and ocular discomfort and redness between groups at the final visit. At 3 months postoperatively, 20/25 or better UDVA was achieved in 95% of the loteprednol group and 92% of the fluorometholone group (P > 0.05). There was neither visually significant corneal haze nor ocular hypertension (IOP rise > 10 mmHg or IOP > 21 mmHg) in any group. CONCLUSION: The efficacy and side effects of loteprednol 0.5% and fluorometholone 0.1% after myopic PRK are comparable.

Changes in Corneal Biomechanical Properties After Descemet Stripping Automated Endothelial Keratoplasty for Pseudophakic Bullous Keratopathy.

PURPOSE: To compare corneal biomechanical properties and intraocular pressure (IOP) in eyes with pseudophakic bullous keratopathy (PBK) before and after Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: This prospective nonrandomized intrasubject comparative study was conducted on 44 eyes of 22 patients with the diagnosis of PBK who underwent DSAEK in one eye. IOP was measured by Goldmann applanation tonometer, and central corneal thickness was measured by ultrasound pachymetry. The ocular response analyzer was used to measure corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-related IOP, and cornea-compensated IOP. The same measurements were performed in the normal fellow eyes which served as controls. All measurements were performed preoperatively and 6 months postoperatively. RESULTS: The mean patient age was 67 ± 14 years. Mean preoperative CH and CRF values in the DSAEK group were 5.77 ± 2.94 and 6.39 ± 2.72 mm Hg, respectively, which were significantly lower than those measured in the control group (8.2 ± 2.47 and 8.43 ± 2.49 mm Hg, respectively, P = 0.001 for both comparisons). Postoperatively, CH and CRF demonstrated a significant increase (7.09 ± 3.68 mm Hg, P = 0.05 and 8.21 ± 3.84 mm Hg, P = 0.03, respectively) in operated eyes approaching the normal values measured in the control eyes. CONCLUSIONS: Corneal biomechanical parameters were significantly lower in PBK eyes than in the normal fellow eyes. These metrics significantly increased after DSAEK and reached values measured in the normal fellow eyes.