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Purpose: To evaluate the effectiveness of previously applied successful accelerated corneal crosslinking (CXL) treatment in keratoconus stabilization during and after pregnancy., Setting: Ankara Yildirim Beyazit University, Ataturk Training and Research Hospital, Turkey., Design: Prospective clinical study., Methods: Patients with stable keratoconus (after having an accelerated CXL procedure) who became pregnant were included. Uncorrected (UDVA) and corrected distance visual acuity (CDVA), manifest astigmatism (MA), keratometry (K)1, K2, Kmax, central corneal thickness (CCT), thinnest corneal thickness (TCT), and anterior (AE) and posterior elevation (PE) were recorded at baseline (before CXL), before pregnancy (the last visit after CXL), during pregnancy (third trimester), and after pregnancy (the last visit after pregnancy)., Results: 24 eyes of 19 patients were included. The mean time between CXL and conception was 12.4 ± 5.1 months. The mean postpartum follow-up period was 27.6 ± 13.3 months. The mean UDVA, CDVA, MA, and PE values did not show any statistically significant differences during and after pregnancy compared with the post-CXL values (P > .05). The mean Kmax flattened significantly after the CXL procedure (P = .011); however, it increased during pregnancy (P = .037, after CXL vs pregnancy) and then decreased back to the prepregnancy level after pregnancy (P = .035, pregnancy vs after pregnancy). The mean K1, K2, AE, CCT, and TCT remained stable during pregnancy and significantly decreased after pregnancy (P < .05)., Conclusions: Keratoconus seems to progress during pregnancy in corneas that have previously received successful accelerated CXL treatment. However, this progress was mostly temporary, and generally, regression occurred after delivery., (Copyright © 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To compare the 36-month visual, refractive, and topographic results and the optical quality of the cornea between mechanical and transepithelial phototherapeutic keratectomy (PTK) epithelium removal techniques prior to the accelerated corneal cross-linking (CXL) procedure in patients with progressive keratoconus., Methods: Keratoconic eyes that received either mechanical epithelium removal or transepithelial PTK epithelium removal prior to accelerated CXL with 36 months of follow-up were included. The uncorrected (UDVA) and corrected (CDVA) distance visual acuity, spherical equivalent (SE), manifest astigmatism, flat keratometry (K1), steep keratometry (K2), maximum keratometry (Kmax) readings, thinnest corneal thickness (TCT), topographic astigmatism, point spread function (PSF), and aberrometric parameters including root mean square higher order aberrations (RMS HOAs), vertical coma, and spherical aberration (SA) were assessed preoperatively and 12, 24, and 36 months postoperatively., Results: One hundred ten eyes of 110 patients with keratoconus were included (mechanical epithelium removal group: 69 eyes, transepithelial PTK epithelium removal group: 41 eyes). After the CXL procedure, the mean UDVA, CDVA, manifest astigmatism, RMS HOAs, SA, vertical coma, and PSF improved significantly throughout the follow-up visits in both groups ( P < .05 for all variables). The improvement in the mean UDVA, CDVA, manifest astigmatism, K1, K2, Kmax, RMS HOAs, SA, vertical coma, and PSF were significantly better in eyes that underwent transepithelial PTK epithelium removal when compared to eyes that underwent mechanical epithelium removal during the follow-up period ( P < .05 for all variables)., Conclusions: Transepithelial PTK-assisted accelerated CXL seems to be more efficient in improving the visual acuity and the optical quality while stabilizing the cornea compared to the accelerated CXL with mechanical epithelium removal in patients with progressive keratoconus. [ J Refract Surg . 2022;38(3):191-200.] .

Purpose : To investigate the impact of long-term scleral contact lens (ScCL) wear on corneal curvature, corneal thickness, tear film function, and ocular surface in patients with keratoconus. Methods : Sixteen keratoconus patients wearing ScCLs for 6 months were enrolled in the study. Corneal topography, tear osmolarity test, Schirmer 1 test, tear film break-up time (TBUT) test, and impression cytology analysis were assessed at baseline and follow-up examinations. Results : There were no significant differences in visual acuity, keratometric and pachymetric values after 6 months of ScCL wear compared to baseline ( p >0.05 for all). Tear osmolarity, Schirmer 1 test, and TBUT test results showed no significant change during follow-up ( p >0.05 for all). Median goblet cell density and grade of squamous metaplasia did not differ significantly at 1-month. However, there was a gradual deterioration in goblet cell density and Nelson grade until the third-month visit compared to baseline ( p for goblet cell, p =0.003; p for Nelson grade, p =0.003). These impaired cytological features observed at 3-month visit persisted at 6-month visit ( p for goblet cell, p =0.008; p for Nelson grade, p <0.001). Conclusion : Six months of ScCL wear did not induce any changes in corneal curvature and thickness and also did not affect tear function tests in keratoconic eyes. The only significant changes observed were a decrease in goblet cell density and metaplastic changes in conjunctival epithelium in impression cytology analysis. Further investigations may be needed to better understand the cause of impairment in cytological features of ocular surface and its clinical implications.

Purpose: To assess the activity of xanthine oxidase (XO) enzyme in keratoconic corneal epithelium and to evaluate its relationship with the keratoconus (KC) severity., Methods: This prospective and randomized study included 66 eyes of 54 KC patients who received corneal collagen cross-linking treatment and 43 eyes of 32 patients who underwent photorefractive keratectomy due to their refractive error. During surgical procedures, the corneal epithelium was mechanically scraped and gathered to analyze the XO enzyme activity spectrophotometrically. The KC group was subdivided into three groups (stages 1, 2, and 3) according to the Amsler-Krumeich classification. The results were compared between the KC and the control group and in between KC subgroups., Results: No significant differences in age and gender were found between the KC and control groups (p = 0.064 and p = 0.296, respectively). The mean XO activity levels of the KC and control groups were 173.57 ± 87.61 and 223.70 ± 99.52 mIU/mg, respectively (p < 0.001). In KC group, 33 eyes were at stage 1, 19 were at stage 2, and 14 were at stage 3. No significant difference was observed between KC subgroups regarding XO activity levels (p = 0.681)., Conclusion: In this study, our findings revealed that ultraviolet-related pro-oxidant XO enzyme may have a role in the etiopathogenesis of KC. Further studies are needed to support our result., Clinical Trials Registration: When we started this study in 2018, we did not have a "Clinical Trials Registration." However, we have ethics committee approval (date: 21. 02. 2018/No: 22).

Purpose: To investigate the long-term effects that CXL has on the tear function and ocular surface in keratoconus., Methods: Twenty-one consecutive patients (24 eyes) with progressive keratoconus scheduled for CXL were included. All patients underwent the following procedures: conjunctival impression cytology analysis, ocular surface disease index (OSDI) score, tear osmolarity test, Schirmer test, tear film breakup time (TBUT), ophthalmic surface fluorescein (Fl) staining, and topographical corneal evaluation before as well as 3 and 18 months after accelerated CXL., Results: There was no change in the median OSDI score, tear osmolarity test, Schirmer test, and the Fl staining score after CXL. The median TBUT increased from 9.00 s at baseline to 12.00 s at 18 months postoperative (P < 0.001). The cytological features of the temporal and superior bulbar conjunctiva deteriorated at 3 months post-CXL (P < 0.001). An improvement in impression cytology analysis of the temporal conjunctiva was noted at 18-month follow-up (P < 0.001). Significant improvements in the median maximum keratometry and mean keratometry (K-mean) readings were also noted 18 months after CXL (P < 0.001). The changes in the K-mean correlated significantly with the changes in TBUT levels at 18-month follow-up as compared to baseline (r =  - 0.688, P < 0.001)., Conclusions: The improvement in TBUT, conjunctival squamous metaplasia, and the goblet cell density indicates a favorable effect of CXL on the ocular surface and tear film in keratoconus, presumably due to the reduced corneal irregularity after CXL.

Purpose: To investigate the elasticity of ocular structures in patients with rheumatoid arthritis (RA) without ocular involvement., Methods: The study included 56 RA patients (study group) and 24 healthy volunteers as the control group. The rheumatoid arthritis patients were divided into two subgroups as those in active phase (Group 1, n = 25) or in remission phase (Group 2, n = 31) according to the disease activity index (DAS 28) score. The elastography values of the ratio of orbital fat-sclera (ROF/S) were measured with real-time US elastography, and corneal mechanical values were measured with the Reichert Ocular Response Analyzer in each eye., Results: The mean ROF/S value was 5.2 ± 1.8 in Group 1, 0.7 ± 0.4 Group 2, and 0.6 ± 0.1 in the control group. There was a significant difference between the Group 1 and control group with regard to ROF/S (p < 0.001), but no significant difference was determined between Group 2 and control group (p > 0.05). The mean ROF/S value was a significant difference between the Group 1 and 2 (p < 0.001). ROF/S was significantly correlated with DAS-28 and C-reactive protein (CRP) (r = 0.816, p < 0.001 and r = 0.259, p = 0.006)., Conclusions: ROF/S was significantly increased in patients in the active phase of RA. Findings revealed that ocular tissue structural changes may occur in the active phase and these could be related to ocular complications as a prognostic factor.

Purpose: To evaluate the role of sex steroid hormone receptors in corneal epithelium in etiopathogenesis of keratoconus (KC)., Methods: Thirty patients with KC who were planned for corneal collagen-crosslinking and 20 patients who were planned for excimer laser for refractive errors included in this study. Corneal epitheliums were curated mechanically during surgeries. Right eyes were evaluated immunohistochemically and left eyes were evaluated by quantitative polymerase chain reaction (qPCR) to investigate estrogenα, estrogenβ, progesterone and androgen receptors., Results: Immunohistochemically, staining for progesterone and androgen receptors did not significantly differ between KC and control groups (p > 0.05). None of the cases had staining for estrogenα and estrogenβ receptors. qPCR showed that mRNA expressions of estrogenα and androgen receptors were significantly higher in the KC group (p < 0.001)., Conclusion: A significantly higher rate of estrogenα and androgen receptor expressions in corneal epithelium from patients with KC through qPCR supports a possible relation between KC and sex steroid hormones., (Copyright © 2018 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: To evaluate visual, refractive, topographic, and aberrometric outcomes of transepithelial phototherapeutic keratectomy (PTK) + corneal collagen crosslinking in the treatment of pellucid marginal degeneration., Methods: This retrospective study includes 20 eyes of 15 patients with pellucid marginal degeneration treated with transepithelial PTK + accelerated corneal collagen crosslinking. Visual acuity, refraction, topographic keratometry, pachymetry, and aberrations were recorded pretreatment and 6, 12, 24, and 36 months after treatment., Results: Stabilization in visual acuity was observed throughout the 36 months of follow-up (P > 0.05). The cylindrical value was significantly lower (P < 0.05) during the follow-up compared with the baseline (4.97 ± 2.00, 3.86 ± 2.01, 3.92 ± 2.27, 2.87 ± 1.70, and 3.28 ± 3.12 D at the baseline and postoperative 6th, 12th, 24th, and 36th month, respectively). Spherical equivalent was significantly lower at the 24th (P = 0.02) and 36th month (P = 0.01) follow-up intervals. A significant decrease (P < 0.05) in average keratometry readings was observed in all follow-up points (47.12 ± 4.66, 46.65 ± 4.38, 46.57 ± 4.57, 46.46 ± 4.81, and 46.27 ± 4.46 D, respectively). The maximum keratometry value remained stable (P > 0.05) in all visits (64.30 ± 10.70, 63.49 ± 10.05, 62.97 ± 9.50, 63.33 ± 10.06, and 62.27 ± 10.36 D, respectively). The Baiocchi Calossi Versaci index was significantly lower (P < 0.05) at all follow-up points compared with the baseline (3.21 ± 1.93, 2.99 ± 1.96, 2.96 ± 1.93, 2.82 ± 1.95, and 2.86 ± 1.99 μm, respectively). Central and minimum corneal thicknesses were significantly lower (P ≤ 0.01) compared with the baseline throughout the follow-up. Higher order aberration, trefoil, coma, and spherical aberration values remained stable during the follow-up compared with the baseline (P > 0.05)., Conclusions: The combination of transepithelial PTK with accelerated corneal collagen crosslinking seems to be an effective treatment in patients with pellucid marginal degeneration in the long-term.

Background and Objective: To evaluate changes in retrobulbar blood flow by using color Doppler ultrasonography (CDUS) after intravitreal ranibizumab injection in patients with neovascular age-related macular degeneration (AMD)., Patients and Methods: Eighteen patients who had undergone intravitreal ranibizumab (0.05 mg/0.05 mL) injection due to choroidal neovascular membrane (CNVM) were included in the study. Contralateral eyes of the patients were also analyzed. Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) were measured from the ophthalmic artery (OA), central retinal artery (CRA), lateral posterior ciliary artery (LPCA), and medial posterior ciliary artery (MPCA) for all patients pre-injection, and at 1 day, 1 week, and 1 month after ranibizumab injection., Results: The mean age of the 18 patients included in the study was 66.94 years (± 8.3 years). Of these 18 patients, eight were female and 10 were male. After Bonferroni's correction for multiple comparisons was carried out, there were significant differences only in some values of LPCA; these included the decrease in EDV and an increase in PI values of LPCA between the pre-injection and post-injection of the first month measurements in uninjected eyes (P = .002, P = .002), and a decrease in PI value of LPCA between post-injection first day and first week measurements in injected eyes (P = .004). There were no statistically significant differences in other parameters., Conclusion: Ocular blood flow velocities may change after intravitreal ranibizumab injection in patients with CNVM. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:437-443.]., (Copyright 2019, SLACK Incorporated.)

We aimed to investigate how orbital blood flow rates in patients with rheumatoid arthritis (RA) are affected by the active and remission phase of the disease. This prospective study included a total of 56 patients with RA (study group) and 24 control individuals (control group). All RA patients were divided into two groups, as active (Group 1) and remission (Group 2) according to the disease activity index (DAS 28) score. For each eye, retrobulbar vascular structures were evaluated [central retinal artery (CRA), posterior ciliary artery (PCA), and ophthalmic artery (OA)], respectively. The peak systolic velocity (PSV) and end-diastolic velocity (EDV) values were obtained for each artery and the vascular resistance index (RI) measurement was calculated. The median RI of the OA was 0.70 (0.57; 0.79) in the control group, 0.77 (0.55; 0.87) in group 1, and 0.73 (0.47; 0.87) in group 2. The median RI in the PCA was 0.70 (0.56; 0.82) in the control group, 0.76 (0.52; 0.88) in the group 1, and 0.74 (0.52; 0.86) in the group 2. The median RI of CRA was 0.73 (0.48; 0.81) in the control group, 0.71 (0.64; 0.81) in group 1, and 0.68 (0.61; 0.85) in group 2. The RI value was a significant difference between control and group 1 (p < 0.05). Active and remission RA patients had different effects on the flow rate of eye blood vessels.

Purpose: To report on a keratoconus (KC) patient with Axenfeld-Rieger syndrome (ARS) who developed sterile keratitis after accelerated corneal collagen cross-linking (CXL)., Methods: An 18-year-old patient with ARS and KC who had previously undergone intrastromal ring segment implantation underwent accelerated CXL (9 mW/cm 2  UVA intensity for 10 min)., Results: After uneventful surgery, the patient presented with severe photophobia, redness of the eye, and decreased vision 72 h following the procedure. Slit-lamp examination showed anterior multiple superficial stromal infiltrates in the central cornea with an overlying epithelium defect. Due to the lack of pain and absence of any pathogen from corneal samples, a diagnosis of sterile keratitis was considered. A combination of topical antibiotic and corticosteroid regimen was administered. Three months after CXL slit-lamp examination showed a mild stromal scar overlying the central cornea, which did not decrease visual acuity., Conclusions: The mechanism by which the sterile keratitis occurs following CXL remains unclear. For our case, the reason of post-CXL sterile keratitis could be considered as an immune response due to the staphylococcal antigens. Furthermore, the possible developmental disturbance of corneal stroma in ARS might have contributed to the development of post-CXL sterile keratitis.

Purpose: To compare heme oxygenase 2 (HO-2) enzyme levels detected by immunohistochemical staining methods in the cornea epithelium obtained from keratoconus patients and normal subjects., Materials and Methods: The keratoconus group included 69 eyes of 69 patients with keratoconus scheduled for cross-linking surgery. The control group included 52 eyes of 52 patients with refractive error scheduled for photorefractive keratectomy surgery. After a detailed ophthalmologic examination, corneal topographic maps of each patient were generated, and then the patients underwent surgery. The corneal epithelium was collected mechanically during the surgery, fixed with formalin, embedded in paraffin blocks, and sectioned by microtomes. HO-2 antibodies were applied to the samples for immunohistochemical evaluation. The intensity of the staining was identified as negative, weak, moderate or strong. The keratoconus group was classified as early (average keratometry (AvrK) ≤ 47 D), moderate (AvrK 47-55 D) and advanced keratoconus (AvrK ≥ 55 D). Finally, intergroup and intragroup comparison analyses were made statistically., Results: In the keratoconus group, 20 (29%) (14 weak and 6 moderate staining) of the 69 corneal epithelial specimens were identified with HO-2 expression. In the control group, 40 (76.9%) (16 moderate and 24 strong staining) of the 52 corneal epithelial specimens were identified with HO-2 expression. HO-2 expression in the corneal epithelial specimens was significantly less in the keratoconus group than in the control group (p < 0.001). There was no substantial difference among the keratoconus subgroups in terms of staining with the HO-2 antibody (p = 0.797)., Conclusions: The HO-2 enzyme staining using immunohistochemical methods was at lower amounts in the keratoconic corneal epithelial cells as compared with normal corneal epithelial cells. The HO-2 enzyme may play a role in the etiopathogenesis of keratoconus.

Purpose: The purpose of the study is to assess changes in optical performance of the cornea in patients with keratoconus following treatment with corneal collagen crosslinking (CXL)., Materials and Methods: One hundred and eleven eyes of 111 consecutive keratoconus patients with 12-month follow-up after CXL were included. The changes in the visual acuity, manifest refractive errors, and corneal topographic parameters were evaluated. Sirius dual-scanning corneal tomography was used to determine the effectiveness of CXL on each patient's total corneal optical quality; preoperative and 12-month postoperative measurements were analyzed over a 4-mm stimulated pupil and were compared with regards to higher order corneal aberrations (total amount of higher order aberrations [HOAs], vertical coma, horizontal coma, vertical trefoil, oblique trefoil, and spherical aberration), vertical and horizontal modulation transfer function (MTF), and Strehl ratio of point spread function (PSF)., Results: At 12 months, there was a significant improvement in mean uncorrected visual acuity (UCVA) (P < 0.001), best corrected visual acuity (BCVA) (P < 0.001), spherical equivalent refraction (P = 0.007), and manifest astigmatic refraction (P < 0.001). The corneal topographic measurements revealed a significant decrease in the mean simulated keratometry-1, simulated keratometry -2, and maximum keratometry compared with the baseline measurements (P < 0.001, for all). In addition, there were significant improvements in mean root mean square error values for corneal total HOA (P < 0.001), vertical coma (P < 0.001), and vertical trefoil (P = 0.008) following CXL. Mean MTF and Strehl ratio did not change after CXL (P > 0.05). The improvement in UCVA significantly correlated with the changes in vertical trefoil (r = -0.191, P = 0.044), and the improvement in BCVA and the changes in manifest astigmatic correction were also significantly correlated (r = -0.247, P = 0.009) 12 months after CXL., Conclusions: CXL treatment for keratoconus led to an improvement in visual, refractive, topographic, and most corneal HOAs outcomes at the 12-month follow-up. However, these improvements were not enough to increase corneal MTF and the Strehl ratio of PSF.

Objectives: To investigate the shifting of the line of sight (LoS) and the refractive, topographic, and aberrometric parameters that may be associated with the shifting of the LoS in eyes with tilted disk syndrome (TDS)., Methods: Eighty left eyes of 80 subjects with TDS (Study Group) and 70 left eyes of 70 subjects with myopia and astigmatism (Control Group) were included in this study. Line-of-sight coordinates on the horizontal (x) and vertical (y) axes, refractive, topographic, and aberrometric parameters were evaluated. All parameters were compared between groups, and correlations were analyzed for the study group., Results: In the study group, the LoS significantly shifted to the superotemporal direction compared with the control group (P=0.022 and P=0.008 respectively). The shift on y-axis was correlated with mean cylindrical refractive error (r=-0.283, P=0.011), total root mean square (RMS) (r=0.321, P=0.004), higher-order aberration RMS (r=0.300, P=0.007), vertical coma (r=0.430, P<0.001), and vertical trefoil values (r=-0.455, P<0.001)., Conclusions: Results demonstrated a superotemporal shifting of the LoS in eyes with TDS. As eyes with TDS have an important place among candidates for refractive and multifocal intraocular lens implantation surgeries, this shift must be accounted for to prevent decentralization and provide satisfactory outcomes.

Purpose: To compare the 24 month visual, refractive, topographic and aberrometric results of the accelerated and standard corneal collagen cross-linking (CXL) in pediatric keratoconus patients., Methods: 87 eyes of 64 consecutive keratoconus patients under 18 years old with 24 month follow-up period following standard or accelerated CXL were included. 38 eyes received standard CXL (3 Mw/cm 2 , 30 min), while 49 eyes had accelerated CXL (9 mW/cm 2 , 10 min). Changes in the uncorrected (UCVA) and best corrected visual acuity (BCVA), spherical equivalent (SE), manifest astigmatism (MA), corneal topographic parameters, and corneal aberrations such as spherical aberration (SA), high order aberrations (HOAs), horizontal and vertical coma were evaluated. Corneal haze was graded and progression rate was assessed., Results: The difference between baseline and 24 months postoperative UCVA, BCVA, SimK (keratometry)-1, SimK-2, Kmax, and the corneal aberrations were not significantly different between the two groups (p > 0.05 for all). The mean reduction in thinnest corneal pachymetry from baseline to 24 months after CXL was higher in accelerated CXL group (p = 0.007). The progression rate was 13.1% in standard and 16.3% in accelerated group (p = 0.754). There were no differences in the grade of corneal haze between the two groups (p = 0.249). No complications were observed in the both groups., Conclusion: The 24 month results of accelerated and standard CXL revealed that, the efficacy and safety of accelerated CXL were the same with standard CXL in pediatric keratoconus patients. As being a rapid procedure, accelerated CXL appears to be more benefical for pediatric patients., (Copyright © 2018 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Platelet-rich fibrin (PRF) is a natural biomaterial and has excellent biochemical and physical properties with a history of proven biocompatibility in the field of tissue engineering and regenerative medicine. Recent reports of fibrin-based matrices have offered new opportunities to apply PRF as a supplement for in vitro cell culture. Here, custom-modified human-derived PRF (HPRF) was produced via different centrifugation protocols, then, characterized by morphologically and chemically and utilized as a substrate and as a conditioned medium for limbal explant culture for the first time. It was found that the HPRF released significantly higher levels of growth factors which are essential for epithelial cell growth. The enhanced physicochemical properties of the HPRF were also proven in the limbal explant cultures in terms of cell growth, migration, viability, and stemness in comparison with the conventional limbal explant culture on human-derived amniotic membrane. Consequently, HPRF hydrogels are appealing natural biomaterials for the purpose of mimicking limbal niche and the discovery elucidates this new, xeno-chemical-free, completely human-derived biomaterial can be utilized as a supplement to promote epithelial cell behaviour in vitro., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose: To compare the 36-month outcomes of mechanical or transepithelial phototherapeutic keratectomy (PTK) epithelial removal before accelerated corneal crosslinking (CXL) for pediatric keratoconus., Setting: Atatürk Training and Research Hospital, Ankara, Turkey., Design: Retrospective case series., Methods: Eyes that had accelerated CXL after mechanical (Group 1) or transepithelial PTK (Group 2) epithelial removal were evaluated preoperatively and 12, 24, and 36 months postoperatively. The uncorrected (UDVA) and corrected distance visual acuities, spherical equivalent (SE), manifest astigmatism, and corneal tomographic and aberrometric parameters were assessed., Results: The study included 40 eyes of 35 consecutive keratoconus patients younger than 18 years with a 36-month follow-up. Group 1 comprised 15 patients, and Group 2 comprised 20 patients. Both groups had a significant improvement in UDVA (P = .001 and P = .02, respectively) and a significant decrease in maximum keratometry (K) and thinnest corneal thickness (all P < .001) 36 months postoperatively. The improvements in maximum K, topographic astigmatism, and spherical aberration were greater in Group 2 than in Group 1 at 12 months (P = .03, P = .01, and P = .04, respectively). After 12 months, the outcomes in the 2 groups were more similar., Conclusions: The initial visual and topographic outcomes of transepithelial PTK ablation were better than those of mechanical epithelium removal before accelerated CXL in pediatric patients with keratoconus. Over the long-term, the results were similar between the 2 groups., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the effects of dehydration and fasting on the intraocular pressure (IOP) and corneal biomechanics during Ramadan in healthy subjects., Methods: A total of 36 healthy fasting male volunteers with a mean age of 32.7 ± 5.1 years (range 28-38 years) were enrolled in the study. A Reichert Ocular Response Analyzer (ORA) was used to measure the corneal resistance factor (CRF), corneal hysteresis (CH), Goldman-correlated IOP (IOPg), and corneal-compensated IOP (IOPcc), additionally IOP with Goldmann applanation tonometer (IOP-GAT) was taken. All measurements were recorded at 8:00 am and 4:00 p.m. during Ramadan and during a 1-month follow-up after Ramadan was over., Results: Statistical analysis demonstrated no difference in the ORA measurements including CH, CRF, IOPcc, and IOPg; CCT and CV values between fasting and non-fasting periods or within a single day (diurnal changes). Nine volunteers (25% of total subjects) were excluded because eyedrops were believed to disrupt the Ramadan fast consequently IOP-GAT could not be measured from these subjects. No statistically significant difference was noted between IOP-GAT and IOPg measurements of twenty-seven subjects at the different periods and time points., Conclusions: Our results reveal that fasting during Ramadan does not profoundly affect corneal biomechanics and IOP values in healthy volunteers without ocular diseases such as glaucoma. When planning corneal refractive surgery and determining IOP, the ORA measurements can be done safely during a Ramadan fast. Moreover, ORA may be a better alternative for patients that refuse IOP measurement via GAT for examining the accuracy of IOP during fasting. Further studies are needed to better understand the role of these parameters on corneal disease and glaucoma during fasting.

A 32 year old female patient with CM 1 diagnosis was referred for the management of papilledema. Ophthalmologic examination revealed normal visual acuity (20/20 in both eyes), normal optic nerve function tests and normal slit-lamp biomicroscopic findings. Fundoscopy revealed bilateral irregular optic nerve heads with blurred margins. B scan ultrasonography (USG) and Spectral domain optical coherence tomography were performed and bilateral optic nerve heads were diagnosed as ODD. We concluded that the pseudopapilledema must be taken into account before making papilledema diagnosis in patients with CM 1 to protect the patients from redundant interventional procedures.

Objective: To investigate the alterations in the ocular surface and tear film parameters 3 months after accelerated corneal collagen cross-linking (A-CXL) in progressive keratoconus (KC) patients., Methods: Twenty-six patients (33 eyes total) with progressive KC were enrolled in this study. All patients were subjected to ophthalmic surface examination, such as OSDI (ocular surface disease index) scoring, the osmolarity tear test, Schirmer test, tear film breakup time (TBUT) analysis, rose bengal (RB) and fluorescein (Fl) ocular surface staining, and conjunctival impression cytology (IC) analysis, respectively. These tests were performed at baseline and 3 months after A-CXL. Nelson's grading system was used to evaluate the cell morphology and goblet cell density., Results: No statistically significant differences in the levels of tear osmolarity, TBUT, Schirmer test, OSDI scoring, and Fl and RB staining between pretreatment and 3 months postoperatively were observed (all P values >0.05). A statistically significant increase in superior (P=0.005) and temporal (P=0.006) IC grading was seen at the postoperative third month compared to pretreatment., Conclusions: Only metaplastic changes and a reduction in the density of the goblet cells were seen in conjunctival IC, which is probably because of the toxicity of ultraviolet-A 3 months after A-CXL. However, these results do not lead to deterioration in TBUT. In this study, A-CXL has no adverse effect on ocular surface and tear function, which are important for visual quality.

Purpose: The aim of this study was to evaluate the corneal biomechanical parameters in patients with ankylosing spondylitis (AS) and to compare them with the healthy subjects., Methods: Sixty patients with AS (study group) and 60 healthy subjects (control group) were enrolled in this prospective study. The study group was further classified as active (n:30) and inactive (n:30). After detailed ophthalmological examination including intraocular pressure (IOP) measurement with Goldmann applanation tonometer (IOPGAT), corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer (ORA). Central corneal thickness (CCT) was measured with the Spectral-Domain Optical Coherence Tomography (SD-OCT)., Results: The study group's mean CH, CCT, IOPg, and IOPGAT values were lower than the control group (p < 0.05 for all variables). The mean CH, CRF, CCT, IOPg, and IOPGAT values were higher in active patients when compared to the inactive ones (p < 0.001, p < 0.001, p = 0.013, p = 0.021, and p = 0.002, respectively)., Conclusions: AS patients have lower CCT, CH, IOPg, and IOPGAT when compared with healthy subjects. In the active stage of AS, patients present with higher levels of corneal biomechanical parameters with thicker corneas. IOPcc is a more accurate measurement than IOPGAT or IOPg in AS patients.

Purpose: To evaluate the thickness of the peripapillary retinal nerve fiber layer (RNFL), total macula, macular ganglion cell layer (GCL), inner plexiform layer (IPL), and choroid in pediatric migraine patients and compare the values with healthy subjects., Methods: This observational and cross-sectional study included 40 patients in the migraine group and 40 healthy control subjects. The thickness of the peripapillary RNFL, total macula, GCL, and IPL was analyzed with spectral-domain optic coherence tomography, while choroidal thickness was analyzed with the enhanced depth imaging protocol. All measurements of the migraine patients were taken in the attack-free period. Right eye selected per subject was included in the study., Results: There was no significant difference between the 2 groups in age or sex (p>0.05). The peripapillary RNFL thickness was not significantly different between the 2 groups in any quadrant. The total macula, GCL, and IPL thickness were also not significantly different in the 9 separate macular areas defined on the basis of the Early Treatment Diabetic Retinopathy Study (p>0.05). The choroidal thickness at 5 different measurement points was not statistically significantly different between migraine patients during the attack-free period and the healthy subjects (p>0.05)., Conclusions: Childhood migraine does not cause changes in posterior ocular structure parameters.

Purpose: To evaluate the change in the location of pupillary center with corneal tomography in keratoconic patients, and determine the correlation of pupillary offset with clinical and topographical features of keratoconus., Methods: Ninety-one eyes of the 54 patients with keratoconus in different stages and 39 eyes of 39 refractive surgery candidates with normal corneas were included in our study. Ocular aberrations and the pupillary offset parameters (x-offset and y-offset) over a 5 mm (undilated) pupil were measured with a Sirius corneal tomographer. A correlation analysis among the pupillary offset parameters and the possible determinative variables (topographical and tomographical parameters, corneal aberrations and best corrected visual acuity) was performed., Results: The mean pupillary offset was significantly greater in the keratoconic eyes compared with the controls (p = 0.003), and the difference was mostly due to the y-offset (p = 0.03). There was no significant difference between the groups in the mean horizontal pupillary offset value (p = 0.07). Both the vertical and the total pupillary offset values correlated significantly (p < 0.0001) with the keratoconus stage (r = 0.58 and r = 0.51, respectively). They also correlated with the corneal aberrations, and negatively correlated with the visual acuity., Conclusions: The pupillary offset seems to correlate with the clinical and topographic features of keratoconus. It may be important to quantify its magnitude and direction in order to ensure correct centralization of the corneal procedures.

The purpose of the study was to evaluate the outcomes and possible complications of CXL performed with customized epithelial debridement technique to keratoconic corneas with the thinnest pachymetry values less than 400 µm. Nineteen eyes of 19 patients were included. The uncorrected (UCVA) and best corrected visual acuity (BCVA), flattest and steepest keratometric (K) readings, central corneal thickness at the thinnest point (t-CCT), endothelial cell density (ECD) were assessed before and 12 months after CXL. The mean UCVA was increased (p = 0.001), while the mean BCVA did not show any difference (p > 0.05). The mean flattest and steepest K readings were decreased (p = 0.001). No change was observed in the mean t-CCT (p > 0.05). The mean ECD was decreased (p = 0.001). The mean pre-CXL and post-CXL percentages of polymegathism and pleomorphism did not show any significant difference (p > 0.05). CXL performed with customized epithelial debridement technique is successful in halting the progression of keratoconus in corneas thinner than 400 µm after 12 months of treatment. However, significant endothelial cell loss can occur after this procedure.

Purpose: To assess the preoperative patient characteristics that may predict outcomes of keratoconus 2 years after corneal collagen cross-linking (CXL) in pediatric patients with keratoconus., Methods: This retrospective study included 72 eyes of 52 consecutive patients with keratoconus under the age of 18 with 2-year follow-up after CXL. Subgroup analysis and cutoff values were determined as per age (<14 and ≥14 years), sex, baseline uncorrected and corrected distance visual acuities (UCVA, CDVA; <0.8 and ≥0.8 logMAR), topographic cone location (central and paracentral), maximum keratometry (K-max, <54 and ≥54 diopters), and corneal thickness at the thinnest point (thCT) (<450 and ≥450 μm) to evaluate the associations between preoperative patient characteristics and outcomes of CXL treatment in terms of K-max. Postoperative progression in K-max was defined as steepening of 1.0 diopter or more., Results: Average age of patients was 14.8 ± 2.2 (9-17) years. After 2 years, the mean UCVA significantly improved and the mean thCT significantly decreased in all patients (P = 0.023, P < 0.001, respectively). The K-max in patients with paracentral cones and/or with thCT less than 450 μm were more likely to progress (cone location: P = 0.023, odds ratio = 3.21, 95% confidence interval, 1.17-8.72; thCT: P = 0.008, odds ratio = 4.54, 95% confidence interval, 1.46-14.14). Age, sex, baseline UCVA, CDVA, and K-max did not present any significant effect on progression of CXL after treatment (P > 0.05 for all variables)., Conclusions: In pediatric patients with keratoconus, cone location and the baseline thinnest corneal thickness seem to affect the success rate of CXL treatment after 2-year follow-up.

Purpose: To report the clinical and histopathological results of a novel autologous scaffold grafting, platelet-rich fibrin (PRF) membrane, in cases with descemetocele., Methods: Three patients with severe corneal stromal melting and central descemetocele caused by neurotrophic keratopathy and infective keratitis underwent PRF membrane grafting on the central cornea for the prevention of imminent corneal perforation. After a quiescent 3-month period, penetrating keratoplasty and cataract extraction were performed for visual rehabilitation in 1 patient and host corneal tissue was examined histopathologically., Results: Pain was significantly relieved, conjunctival inflammation was markedly resolved, and the central descemetocele area became thicker with scar formation in all patients. Histopathological examination revealed fibrosis formation over the descemetocele area without any tissue gap. Newly formed tissue containing irregular corneal lamellae covered the fibrosis formation and accounted for the prevention of perforation., Conclusions: Temporary PRF membrane grafting may be an alternative intervention to avoid impending corneal perforation in cases with severe descemetocele.

Objective: To investigate corneal biomechanical properties among individuals with unilateral nonarteritic anterior ischemic optic neuropathy (NAION) compared to healthy gender- and age-matched subjects., Methods: The study subjects were separated into 2 groups: 66 eyes of 33 patients with unilateral NAION (study group) and 33 eyes of 33 healthy individuals (control group). Reichert ocular response analyzer (Reichert Ophthalmic Instruments) was used to assess corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated intraocular pressure values. Also, central corneal thickness was measured using Scheimpflug camera combined with a Placido disc corneal topographer (Sirius; Costruzioni Strumenti Oftalmici)., Results: Mean CH and median CRF values were significantly lower in the affected eyes (8.8 ± 1.8 mm Hg, 9.4 mm Hg, respectively) and contralateral unaffected eyes (9.1 ± 1.6 mm Hg, 9.8 mm Hg, respectively) of NAION patients than those in the control group (9.9 ± 1.3 mm Hg, 10.4 mm Hg, respectively; all P < 0.017). Mean IOPcc was significantly higher in the affected eyes of NAION patients (19.2 ± 3.5 mm Hg) than in the eyes of control group (17.1 ± 3.6 mm Hg; P = 0.002)., Conclusions: CH and CRF are significantly reduced in patients with NAION, possibly indirectly reflecting structural weakness in the lamina cribrosa.

Purpose: The aim of this study was to compare the biomechanical parameters of the cornea and intraocular pressure (IOP) before and after hemodialysis (HD) in patients with end-stage renal disease (ESRD) and also healthy subjects., Materials and Methods: Twenty-one patients with ESRD undergoing HD treatment (study group) and 21 healthy individuals (control group) were enrolled in this prospective study. Right eyes of each subjects were included. Central corneal thickness (CCT) were measured using Sirius Scheimpflug camera. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-related IOP (IOPg) were measured using ocular response analyzer. In the study group, measurements were taken just before HD and 30 minutes after HD., Results: The mean CCT, CRF, IOPg values did not differ between pre-HD, post-HD, and controls (P > 0.05). CH was found to be significantly higher in control group (10.6 ± 1.2 mm Hg) when compared with pre-HD (8.07 ± 1.8 mm Hg) and post-HD (8.8 ± 1.6 mm Hg) CH values (P = 0.0001). The mean IOPcc values did not differ pre-HD (18.5 ± 3.5 mm Hg) and post-HD (17.8 ± 3.9 mm Hg) (P = 0.39). The mean IOPcc values were lower significantly in control group (15.4 ± 2.8 mm Hg) when compared with pre-HD and post-HD values (P = 0.02 and 0.02, respectively). Significant correlations were seen between post-HD CRF and post-HD CCT (r = 0.6, P = 0.03); and post-HD IOPg and post-HD CCT (r = 0.51, P = 0.01)., Conclusions: ESRD may disrupt the biomechanical properties of the cornea. Changes in ocular response analyzer parameters should be kept in mind to evaluate accurate IOP measurements in patients with ESRD.

Ocular changes are commonly encountered in various endocrine disorders. However, only a few studies have reported ocular changes in patients with primary hyperparathyroidism (PHPT). Here, we examined the central corneal thickness (CCT), retinal thickness (RT), and intraocular pressure (IOP), and their relationships with serum intact parathyroid hormone (iPTH), calcium (Ca), and phosphorus (P) levels in patients with PHPT. Thirty-seven eyes of 37 PHPT patients were compared with 43 eyes of 43 age- and sex-matched normal subjects. A detailed ophthalmologic examination, including CCT, RT, and IOP, was performed. CCT and IOP in PHPT patients were significantly higher than controls (p = 0.024 and p = 0.038, respectively). No statistically significant difference was detected in RT between the two groups (p = 0.730). iPTH levels were positively correlated with CCT and IOP (r = 0.304, p = 0.006 and r = 0.249, p = 0.026, respectively). No significant correlation was found between iPTH levels and RT (p > 0.05), and between serum Ca levels, and RT, CCT, and IOP (all, p > 0.05). While there was a negative correlation between serum P levels and CCT (r = -0.264, p = 0.018), no correlation was observed between serum P levels, and RT and IOP (both, p > 0.05). Using multiple regression analyses, iPTH, serum Ca, and serum P levels were found to have no significant associations with CCT, IOP, and RT (all, p > 0.05). There was no significant association between PHPT, and CCT, RT, and IOP. We postulate that the identification of ocular aspects of PHPT is significant, and further studies related to this condition are required.

Purpose: To investigate the variations in biomechanical properties of the cornea in rheumatoid arthritis (RA) patients., Methods: A total of 53 RA patients, and 25 healthy individuals (control group) were enrolled. Rheumatoid arthritis patients were classified as in active phase (group 1; n=24) or in remission phase (group 2; n=29). Corneal biomechanical parameters including corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer. Topographical measurements, including central corneal thickness (CCT), anterior chamber depth, iridocorneal angle, and corneal volume were measured using a Sirius corneal topographer., Results: The mean CH was 9.43±1.17 mm Hg in group 1, 9.42±1.84 mm Hg in group 2, and 10.47±1.68 mm Hg in the control group (P=0.03). The mean IOPcc was 17.85±3.2 mm Hg in group 1, 17.95±3.49 mm Hg in group 2, and 15.36±3.11 mm Hg in the control group (P=0.008). The CH showed a significant positive correlation with CRF (P=0.000, r=0.809) and CCT (P=0.000, r=0.461), and a significant negative correlation with IOPcc (P=0.000, r=-0.469)., Conclusions: Decrease in the mean CH measurements indicates that ultrastructural changes in the cornea may occur in the active phase, and these changes persist in the remission period. In addition, IOPcc is significantly affected by the corneal biomechanical properties. In RA patients, it is important to control the corneal parameters and IOP measurements against the irreversible changes on the optic nerve.

Purpose: To compare the complications occurring within the first 3 months of corneal collagen crosslinking (CXL) performed with mechanical or transepithelial phototherapeutic keratectomy (PTK) epithelial removal in keratoconus patients., Setting: Yildirim Beyazit University Ataturk Training and Research Hospital, Ankara, Turkey., Design: Nonrandomized retrospective clinical study., Methods: Eyes of consecutive progressive keratoconus patients who had PTK or mechanical epithelial removal followed by CXL were included. All patients were examined regularly until epithelial healing. Detailed ophthalmologic examinations were performed preoperatively and 1 and 3 months postoperatively., Results: The study comprised 499 eyes (302 patients) that had transepithelial PTK (Group 1, 153 eyes) or mechanical epithelial removal (Group 2, 256 eyes) followed by CXL. Delayed epithelial healing occurred in 15.0% of eyes in Group 1 and 3.5% of eyes in Group 2 (P = .001). Epithelial hypertrophy occurred in 24.8% of eyes and 3.5% of eyes, respectively (P = .001). Salzmann-like epithelial nodules (2.6%), epithelial herpetic keratitis (1.9%), anterior uveitis (1.9%), and elevated intraocular pressure (1.9%) occurred in Group 1 only and infective keratitis (0.8%) in Group 2 only. Marked stromal edema and peripheral sterile infiltrates occurred at similar rates in both groups (P = .567 and P = .479, respectively). Grade 1+ corneal haze was significantly high in Group 2. Grade 2+ and 3+ haze was significantly high in Group 1 (P = .001)., Conclusions: Ocular surface healing disorders were the most common early complications of CXL. Short-term complications were higher with the transepithelial PTK epithelial removal technique than with mechanical epithelial removal., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Aim: To determine the effect of refractive error on temperament and character properties using Cloninger's psychobiological model of personality., Methods: Using the Temperament and Character Inventory (TCI), the temperament and character profiles of 41 participants with refractive errors (17 with myopia, 12 with hyperopia, and 12 with myopic astigmatism) were compared to those of 30 healthy control participants. Here, temperament comprised the traits of novelty seeking, harm-avoidance, and reward dependence, while character comprised traits of self-directedness, cooperativeness, and self-transcendence., Results: Participants with refractive error showed significantly lower scores on purposefulness, cooperativeness, empathy, helpfulness, and compassion (P<0.05, P<0.01, P<0.05, P<0.05, and P<0.01, respectively)., Conclusion: Refractive error might have a negative influence on some character traits, and different types of refractive error might have different temperament and character properties. These personality traits may be implicated in the onset and/or perpetuation of refractive errors and may be a productive focus for psychotherapy.

Context: There is a generalization that "antihypertensive (antiHT) therapy causes Dry Eye Syndrome", which has been claimed for years however most of the publications are epidemiological studies. We performed a clinical study to investigate the effects of antiHT agents on tear function., Objective: The aim of this article is to evaluate the effects of different classes of antiHT medications on tear osmolarity, ocular surface problems and dry eye symptoms., Materials and Methods: Prospective, non-randomized a clinical study. A total of 71 patients who would be initiated antiHT medication due to elevated systemic blood pressure were included in the study. Thirty of these patients were given antiHT drugs containing diuretic (diuretic +), and 41 of them were given diuretic-free drugs (diuretic -). While the number of the patients medicated in the group that received Angiotensin Converting Enzyme inhibitors (ACE inh)/Angiotensin receptor blockers (ARB) (ACE/ARB +) was 29, the number of those medicated in the ACE/ARB-free group (ACE/ARB -) was 42. Ocular surface disease index scores, tear osmolarity, Schirmer I test, tear film break-up time (TBUT), fluorescein (FL) and rose bengal corneal staining patterns of the patients were analyzed. The patients were examined through the repetition of all the tests in the 1st and the 3rd month., Results: The participants (n = 71) comprised 38 males and 33 females with a mean age of 51.8 ± 10.4. When the first (0-1st month) and the third month (0-3rd months) control measurements between diuretics (+) and diuretics (-) groups before and after antiHT therapies were compared, a statistically significant difference was not found in any of the tests applied. When the 0-1st month measurements of ACE/ARB (+) and ACE/ARB (-) groups were compared, it was observed that staining with FL in ACE/ARB (+) group decreased in a statistically significant manner (p = 0.035) and there was a significant increase in TBUT values (p = 0.022)., Discussion and Conclusion: The use of antiHT drugs containing diuretic had no adverse effect on the tear function tests, but using drugs that contain ACE/ARB could have a positive impact.

Purpose: The aim of this study was to compare topographic and biomechanical properties of corneas in patients with acromegaly with those of healthy individuals., Methods: Thirty-five patients with acromegaly (study group) and 35 healthy individuals (control group) were enrolled in this prospective study. Topographic measurements, including central corneal thickness (CCT), mean keratometry (K) value, K1, K2, surface asymmetry index, corneal volume (CV), and anterior chamber depth in the right eye of each participant were obtained using a Scheimpflug camera with a Placido disc topographer (Sirius; Costruzione Strumenti Oftalmici). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOP), and Goldmann-corelated intraocular pressure (IOPg) were measured using Reichert Ocular Response Analyzer (Reichert Ophthalmic Instruments)., Results: Mean CCT, CV, CH, CRF, and IOPg values were higher in acromegalic eyes (549.3 ± 30.2 μm, 59.1 ± 3.1 μm, 11.3 ± 1.2 mm Hg, 11.3 ± 1.2 mm Hg, and 17.5 ± 2.9 mm Hg, respectively) than in healthy eyes (531.4 ± 33.6 μm, 57.4 ± 2.7 μm, 10.4 ± 1.2 mm Hg, 10.2 ± 1.6 mm Hg, and 14.8 ± 3.1 mm Hg, respectively; CCT, P = 0.042; CV, P = 0.032; CH, P = 0.044; CRF, P = 0.035; IOPg, P < 0.001)., Conclusions: CCT, CV, CH, CRF, IOPg, and IOP with Goldmann applanation tonometry were significantly higher in acromegalic eyes. These corneal topographic and biomechanical properties, disease duration, and disease status should be considered when planning corneal refractive surgery and determining accurate intraocular pressure in patients with acromegaly.

Objective: To investigate the effects of corneal epithelium on corneal curvature in patients with keratoconus., Design: This is a prospective, nonrandomized study., Participants: Fifty-nine eyes of 47 patients diagnosed as keratoconus and for whom corneal collagen crosslinking (CXL) was recruited in this study., Methods: This study is a single-center clinical trial. Pregnancy, lactation, connective tissue disease, corneal thickness below 350 μm, severe dry eyes, or scar of corneal surgery were exclusion criteria. Before and during CXL procedure after removing the corneal epithelium, maximum values of corneal apical curvature, simulated keratometry 1 (Sim-K1), simulated keratometry 2 (Sim-K2), temporal and inferior curvature values, all of which are 1.5 mm from the corneal center, were calculated. These values before and after removal of epithelium were compared statistically., Results: Mean age of patients was 23.30 ± 5.5 (12-38) years. Twenty-eight (59%) were male while 19 (41%) were female. Mean values measured before and after removing the corneal epithelium were: apical curvature; 59.19 ± 7.2 (47.06-82.40) diopter (D) and 61.70 ± 8.8 (49.19-92.66) D (p = 0.001), SimK1; 47.57 ± 4.3 (39.14-64.57) D and 48.23 ± 4.3 (41.89-66.70) D (p = 0.001), SimK2; 52.04 ± 5.3 (43.56-69.34) D and 53.34 ± 5.6 (43.73-70.89) D (p = 0.001), inferior curvature; 53,85 ± 5.2 (43.47-76.56) D and 55.05 ± 5.8 (44.56-81.93) D (p = 0.002), temporal curvature 49.49 ± 5.1 (41.50-71.03) D and 51.53 ± 5.4 (41.58-73.34) D (p = 0.001), respectively., Conclusions: In keratoconus patients during CXL treatment, after removing the corneal epithelium, more steepness is detected in the curvature of the steeper area of the cornea. When evaluating patients with keratoconus, the masking effect of corneal epithelium on values of curvature should be taken into consideration.

Objective. To investigate the biomechanical characteristics of the cornea in patients with mitral valve prolapse (MVP) and the prevalence of keratoconus (KC) in MVP. Materials and Methods. Fifty-two patients with MVP, 39 patients with KC, and 45 control individuals were recruited in this study. All the participants underwent ophthalmologic examination, corneal analysis with the Sirius system (CSO), and the corneal biomechanical evaluation with Reichert ocular response analyzer (ORA). Results. KC was found in six eyes of four patients (5.7%) and suspect KC in eight eyes of five patients (7.7%) in the MVP group. KC was found in one eye of one patient (1.1%) in the control group (P = 0.035). A significant difference occurred in the mean CH and CRF between the MVP and control groups (P = 0.006 and P = 0.009, resp.). All corneal biomechanical and topographical parameters except IOPcc were significantly different between the KC-MVP groups (P < 0.05). Conclusions. KC prevalence is higher than control individuals in MVP patients and the biomechanical properties of the cornea are altered in patients with MVP. These findings should be considered when the MVP patients are evaluated before refractive surgery.

A 50 year-old male patient was referred to our clinic due to a floating mass in the right eye. The uncorrected visual aquity was 10 / 10 in both eyes.The patient did not have any systemic disorder and trauma history. His ophthalmological examination revealed an unremarkable anterior segment with no signs of inflammation. Indirect opthalmoscopy and posterior segment biomicroscopy performed with 90D lens was unremarkable in the left eye, while in the right eye a single oval cyst was identified floating freely in the vitreous. The cyst was partially masking the underlying retinal vasculature. B-scan ultrasound revealed an echo-free, round-shaped cyst that was free from surrounding vitreous strands or retina localised at the posterior vitreous. Fluorescein angiography (FA) ruled out the presence of intra and overlying vascularisation of the cyst. Indeed, FA showed a clear-edged hypofluorescence due to a pre-retinal masking effect. The indirect hemaglutinin tests of the patient for ecinococcus and cysticercosis were negative. Eosinophilia was not detected in the preripheral blood smear. Based on these findings the patient was diagnosed as primary vitreal cyst. The presented case was mild symptomatic so the patient was decided to be followed up without any treatment.

Purpose: To evaluate the oxidative stress status and anti-oxidative defence in patients with age-related macular degeneration (AMD)., Methods: A total of 22 patients diagnosed with AMD and 23 age-matched healthy controls were included in the present study. Serum levels of total oxidant status (TOS), total antioxidant status (TAS), total thiol status (TTS) and paraoxonase 1 (PON1) activity were investigated from samples., Results: Significant increase in TOS levels were observed in sera of AMD patients (25.3 ± 12.8) compared to controls (15.0 ± 4.4). TTS (404.3 ± 55.3) and serum PON1 enzyme activities (163.0 ± 65.5) were significantly lower in AMD patients (594.0 ± 64.2) relative to control groups (252.8 ± 132.7)., Conclusion: The results of the present study show that there is a significant increase in oxidative stress in AMD patients and significant decrease in antioxidant defence, in the total thiol level and in PON1 activity in AMD patients compared with controls. The increased oxidative stress and decreased antioxidant levels may have a synergistic role in AMD development.

Aim: To study the relationship between corneal white-to-white (WTW) distance and mesopic pupil diameter., Methods: This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis., Results: Mean pupil diameter was (6.39±0.80)mm (range: 3.70mm-7.73mm). Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was (11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R=0.598, R(2)=0.358 P=0.02)., Conclusion: This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.

Purpose: To evaluate changes in corrected distance visual acuity (CDVA) after photorefractive keratectomy (PRK) in amblyopic cases., Setting: Ankara Ataturk Training and Research Hospital 1st Ophthalmology Clinic, Ankara, Turkey., Design: Retrospective case series., Methods: The medical records of cases of anisometropic amblyopia treated by excimer laser PRK were reviewed. Inclusion criteria were no previous refractive correction, occlusion treatment, or chemical penalization before age 15 years. Anisometropic amblyopia was defined as a more than 2-line difference in CDVA and a refractive error difference greater than 3.00 diopters (D) between 2 eyes of the same patient. Final visual acuity measurements were performed at the end of the sixth postoperative month., Results: The study enrolled 16 hyperopic patients and 34 myopic patients with a mean age of 33.3 years. The mean preoperative spherical equivalent was -7.46 D ± 2.90 (SD) in myopic eyes and +4.15 ± 2.56 D in hyperopic eyes. The differences between the preoperative and postoperative uncorrected distance visual acuity and CDVA were statistically significant (P=.001). The mean CDVA was 0.47 ± 0.17 preoperatively and 0.61 ± 0.19 postoperatively. The CDVA decreased in 3 cases (6%), stayed the same in 12 cases (24%), and increased in 35 cases (70%). There was no statistically significant correlation between the severity of amblyopia and the increase in CDVA (r = 0.20, P=.165)., Conclusion: After PRK to eliminate and correct refractive errors in anisometropic amblyopia, visual acuity improved significantly in 70% of adult patients with no previous occlusion or chemical penalization treatment., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Background and Objective: To determine important factors causing decentration after laser-assisted subepithelial keratectomy (LASEK)., Patients and Methods: A total of 223 cases (446 eyes) were evaluated after LASEK using corneal topography to determine the amount of decentration. Decentration and pupillary offset values and their components on the nasal, temporal, superior, and inferior axes were analyzed with the t test and the two-way repeated measures analysis of variance test in patients with myopia or hypermetropia. Correlation analysis between the amount of decentration and the possible determinative variables (age, gender, spherical refractive error, magnitude of astigmatism, spherical equivalent, average keratometry, mesopic pupil diameter, decentration, and pupillary offset) were performed., Results: Although decentration up to 0.99 mm was observed, mean decentration was 0.26 ± 0.16 mm. Alternatively, pupillary offset values were higher and the mean pupillary offset was 0.28 ± 0.16 mm. In myopia, mean total decentration was significantly less than hyperopia (P = .001). The inferior component of decentration was higher than the other locations in both myopia and hypermetropia. The nasal component of pupillary offset was highest among others. When all cases were included in the analysis, Pearson correlation analysis showed a statistically significant correlation between decentration and presence of hyperopia (r = 0.162 and P =.001) and amount of pupillary offset (r = 0.296 and P = .001)., Conclusion: Mean decentration was higher in hyperopia than in myopia. Most of the decentration may be attributed to inferior decentration. Pupillary offset values were the factor most significantly correlated to the amount of decentration in all cases., (Copyright 2010, SLACK Incorporated.)

Objective: To evaluate the effects of injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative on the corneal endothelium in phacoemulsification cataract surgery., Methods: This retrospective study comprised 70 patients with age-related cataracts who had undergone phacoemulsification cataract surgery with intraocular lens (IOL) implantation without any surgical complications. In the adrenalin group, patients with intraoperative intracameral adrenalin use were included. The intracameral adrenalin was composed of 1 mL of 1:100,000 dilution adrenalin with sodium bisulfite preservative. The control group included patients who underwent surgery without any intracameral adrenaline use. There were 36 patients in the adrenalin group and 34 patients in the control group. Corneal endothelial density, endothelial cell morphology, and endothelial cell area were measured via specular microscopy both preoperatively and 3 months after surgery. The 2 groups were compared with regard to changes in specular microscopy measurements., Results: The mean (+/- standard deviation) age was 66.51 +/- 8.32 years in the adrenalin group and 67.58 +/- 7.83 years in the control group. The difference in age between the 2 groups was not significant (p = .611). The preoperative mean corneal endothelial cell density was 2,270 +/- 286 cells/mm(2) in the adrenalin group and 2,226 +/- 260 cells/mm(2) in the control group, and the difference between the 2 groups was not statistically significant (p = .550). In the adrenalin group, the postoperative mean corneal endothelial cell density was 2,191 +/- 268 cells/mm(2). Although the postoperative mean cell density was lower than the preoperative mean cell density, the difference between the 2 measurements was not statistically significant (p = .117). In the control group, the postoperative mean corneal endothelial cell density was 2,169 +/- 272 cells/mm(2), and the difference between the preoperative and postoperative measurements was not statistically significant (p = .161). Comparisons of postoperative specular microscopy measurements between the adrenalin and control groups with regard to cell density, cell sizes, and cell shapes showed that there were no statistically significant differences in comparison of all parameters between the 2 groups., Conclusions: Intracameral injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative is not toxic to corneal endothelium.

Purpose: To identify factors which affect mesopic pupil diameter in refractive surgery patients., Setting: This retrospective study was performed at the 1st Ophthalmology Clinic in Ankara Ataturk Training and Research Hospital, Ankara, Turkey., Methods: Medical records of 412 refractive surgery candidates who applied between 2006 and 2008 were reviewed. Detailed ophthalmological examination data were obtained from medical records. Pupil size measurements were performed with a COAS Ocular Wavefront analyzer in mesopic conditions. Relationship between mesopic pupil diameter and age, sex, spherical refractive error (D), magnitude of astigmatism (D), type of astigmatism, spherical equivalent, and average keratometry were analyzed by means of univariate and multivariate regression analyses., Results: Mean mesopic pupil diameter was 6.19 +/- 0.88 mm. Mean pupil diameter (mean +/- standard deviation) was 5.70 +/- 1.01 in hypermetropia, 6.04 +/- 0.79 mm in mixed astigmatism, and 6.33 +/- 0.82 mm in myopia. The difference in mean mesopic pupil diameters between myopes and hypermetropes was statistically significant (p = 0.001). However, differences with regard to mean pupil diameters between myopes and mixed astigmatism (p = 0.660) and between hypermetropes and mixed astigmatism (p = 0.109) were not significant. Mean pupil diameter was 6.00 +/- 0.99 mm in against the rule astigmatism, 5.96 +/- 0.84 mm in oblique astigmatism, and 6.27 +/- 0.84 mm in with the rule astigmatism. Mean mesopic pupil diameter in with the rule astigmatism group was higher than oblique astigmatism group. Spherical refractive error (r = -0.213, p = 0.001), cylindrical refractive error (0.197, p = 0.001), and age (r = -0.341, p = 0.001) showed correlation with pupil diameter., Conclusions: This study showed that age and magnitude of both spherical and cylindrical refractive error are the most determinative factors on mesopic pupil size.

Purpose: To evaluate the effectiveness and therapeutic range of laser-assisted subepithelial keratectomy (LASEK) without mitomycin-C (MMC) to treat high myopia., Setting: Isik Eye Clinic, Ankara, Turkey., Methods: This study comprised 31 highly myopic eyes (19 patients) that had LASEK. Before primary LASEK treatment and 1, 3, 6, 12, and 24 months after, all patients had a complete ophthalmic examination including visual acuity, refractive outcomes, and biomicroscopy., Results: The mean spherical equivalent (SE) was -9.01 diopters (D) +/- 2.66 (SD) preoperatively and -1.00 +/- 1.15 D at the end of follow-up. At 24 months, the mean SE was within +/-1.00 D of the intended correction in 23 eyes (74.19%). The median uncorrected visual acuity (UCVA) increased from 20/606 preoperatively to 20/28.6 at 24 months and the median best corrected visual acuity, from 20/25 to 20/22, respectively. Total higher-order and spherical aberrations increased significantly at the end of follow-up. All 14 eyes that had ablations greater than -8.62 D developed varying degrees of haze. Significant myopic regression (>1.00 D) leading to UCVA loss occurred in all eyes with a preoperative SE of -12.00 D or greater., Conclusions: The results of LASEK without MMC were excellent in eyes with up to -8.6 D of SE. All eyes with a preoperative SE between -8.6 and -12.0 D developed haze but had acceptable refractive and visual outcomes. Haze and myopic regression limited the success of LASEK in eyes with a preoperative SE of -12.0 D and greater.

Purpose: To evaluate the effectiveness of laser-assisted subepithelial keratectomy (LASEK) to treat residual refractive errors after laser in situ keratomileusis (LASIK)., Settings: Isik Eye Clinic, Ankara, Turkey., Methods: This retrospective study included 24 eyes of 15 patients who had retreatment by LASEK for residual refractive errors after myopic LASIK. All patients had examinations that included slitlamp biomicroscopy, subjective and cycloplegic refractions, uncorrected visual acuity (UCVA), best corrected visual acuity, corneal topography, and pachymetry preoperatively and postoperatively. Postoperative examinations were performed at 1 week and 1, 3, and 6 months., Results: The patient cohort comprised 9 men and 6 women. The median spherical equivalent (SE) of attempted correction for retreatment with LASEK was -1.25 diopters (D). The median follow-up after LASEK was 11.5 months (range 6 to 16 months). At the end of the follow-up, the median SE of the refractive error was -0.38 D. The median UCVA increased from 20/45 before LASEK to 20/25 at the last follow-up visit, which was statistically significant (P<.001). After LASEK, significant postoperative haze developed in 5 eyes. In all 5 eyes, the estimated ablation depth was more than 40 mum and the SE of attempted correction was -2.00 D or greater., Conclusions: Laser-assisted subepithelial keratectomy retreatment in eyes with myopic regression after LASIK resulted in a significant improvement in UCVA that was comparable to the improvement after flap lifting. An SE of attempted correction greater than -2.00 D was associated with a significant rate of haze.

Prostaglandin F2 alpha (PGF2 alpha) as its tromethamine salt was topically applied, and hypotensive and other ocular effects were studied, in glaucomatous human eyes. After baseline intraocular pressure (IOP) measurements, 100 micrograms PGF2 alpha tromethamine salt dissolved in 50 milligrams saline was applied to 23 glaucomatous eyes of 20 patients. The pretreatment diurnal IOP values of the same eye served as control group. It was found that in comparison with baseline values, PGF2 alpha caused significant but transient elevation in IOP in the first half-hour (mean 1.95 mm Hg, p < 0.01), but it decreased below baseline values at the first hour. A significant decrease in IOP from baseline was observed at the 2nd hour (p < 0.05), which became more prominent between the 4th and 24th hours (p < 0.001). PGF2 alpha produced a maximal IOP reduction of 10.21 mm Hg at the 12th hour (p < 0.001). The IOP differences between PGF2 alpha-treated and control groups were significant between the 4th and 24th hours (p < 0.001), with the maximal IOP difference of 9.21 mm Hg at the 12th hour (p < 0.001). PGF2 alpha caused marked conjunctival hyperaemia in all eyes. Aqueous flare and cellular response were not seen in any of the eyes. Half of the patients experienced ocular smarting or a foreign-body sensation, periocular pain and headache. PGF2 alpha reduced IOP effectively in glaucomatous human eyes.