ALTERED BLOOD AND AQUEOUS HUMOR LEVELS OF ASPROSIN, 4-HYDROXYNONENAL, AND 8-HYDROXY-DEOXYGUANOSINE IN PATIENTS WITH DIABETES MELLITUS AND CATARACT WITH AND WITHOUT DIABETIC RETINOPATHY.

PURPOSE: Diabetic retinopathy (DRP) is the formation of edema and small vessels in the retina due to high blood glucose levels. Asprosin is a hormone that stimulates the release of glucose from the liver into the circulation. Considering the relationship between oxidative stress and DRP, our study aimed to determine the levels of the oxidative stress markers 4-hydroxynonenal (4-HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), as well as asprosin, in the blood and aqueous humor (Aq) of patients with and without DRP. METHODS: Thirty patients with single-eye DRP and cataract (DRP + C), 30 patients with diabetes mellitus and cataract without DRP (DM + C), and 30 healthy control (CON) participants were enrolled into this retrospective study. Except for healthy controls, Aq and blood samples were taken from these patients during their cataract operation. Asprosin, 4-HNE, and 8-OHdG concentrations were analyzed using enzyme-linked immunosorbent assays. RESULTS: In patients with DRP, the levels of asprosin, 4-HNE, and 8-OHdG were significantly higher in both Aq and blood samples compared with the group of patients without DRP. CONCLUSION: These findings suggest that the measurement of asprosin, 4-HNE, and 8-OHdG levels may support clinicians in determining the risk of DRP development.

Branch retinal vein occlusion associated with platelet activation

Background/aim: The aim of this study is to study subclinical platelet activation by detecting three important platelet activation parameters of mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) in patients with branch retinal vein occlusion (BRVO) in comparison to those in healthy control subjects. Materials and methods: This prospective study included 43 patients with BRVO (Group 1)and 40 control subjects (Group 2). The levels of MPV, PDW, and PCT were measured in both of the studied groups Results: The mean serum level of MPV value was 7.64 ± 0.64 in Group 1 and 7.39 ± 0.42 in Group 2. Mean serum level of PDW was 15.01 ± 1.56 in Group 1 and 14.43 ± 1.03 in Group 2. Mean serum PCT value was 0.19 ± 0.05 in Group 1 and 0.16 ± 0.04 in Group 2. MPV, PDW, and PCT levels were significantly increased in BRVO patients (P < 0.05). Conclusion: Subclinical platelet activation reflected by MPV, PDW, and PCT may have an impact on the genesis of vessel occlusion in BRVO. The results may be important for the clinical management of patients with BRVO

Increased levels of circulating CD34+ cells in neovascular age-related macular degeneration: relation with clinical and OCT features.

PURPOSE: To investigate the levels of circulating CD34+ stem cells in patients with neovascular type age-related macular degeneration (AMD) and its relation with clinical and optical coherence tomography (OCT) findings. METHODS: The study consisted of 55 patients: 28 patients (18 male and 10 female) with neovascular type AMD as a study group and 27 patients (12 male and 15 female) scheduled for cataract surgery as a control group. The level of CD34+ stem cells was measured by flow cytometry. Demographic and clinical data were recorded. RESULTS: The mean ages of patients in the study and control groups were 71 ± 8 and 68 ± 6 years, respectively. There was no statistically significant difference in terms of age, sex, or systemic disease association between study and control groups. However, smoking status was significantly higher in the study group (67.9% vs 37.0%; p = 0.02). Stem cell levels were significantly higher in the study group (1.5 ± 0.9 vs 0.5 ± 0.3; p<0.001), but there was no relation between stem cell levels and clinical and OCT findings. CONCLUSIONS: Increased circulating CD34+ stem cell levels were observed in patients with choroidal neovascular membrane associated with AMD, but no significant relation was found between cell levels and clinical and OCT findings.

Evaluation of biomechanical properties of the cornea in patients with primary hyperparathyroidism.

The purpose of this study is to compare the corneal biomechanical properties in primary hyperparathyroid patients and healthy control subjects. The study consisted of 31 patients with primary hyperparathyroidism (study group) and 31 healthy subjects (control group). Corneal biomechanical properties, including corneal hysteresis (CH), corneal resistance factor (CRF), and intraocular pressure (IOP) were measured with an ocular response analyzer (ORA). IOP was also measured using Goldmann applanation tonometry (GAT), and central corneal thickness (CCT) was measured with an ultrasonic pachymeter. The differences in ORA parameters and CCT between study and control group participants were analyzed. The mean CH in study and control groups was 8.7 ± 1.9 mmHg (5.3-13.7 mmHg) and 9.8 ± 1.5 mmHg (7.7-14.3 mmHg), respectively (p = 0.018). The mean CRF was 9.5 ± 1.8 (5.5-13.7) in the study group compared with 9.8 ± 1.5 (6.2-12.8) in the control group. The difference for CRF was not statistically significant (p = 0.41). In study and control group, corneal-compensated IOP (IOPcc) values were 18.2 ± 4.2 and 16.9 ± 2.7 mmHg, respectively (p = 0.12). Mean IOP measurement values with GAT were 16.3 ± 3.4 mmHg for study group and 16.5 ± 2.7 mmHg for control group (p = 0.71). The mean differences of IOPcc and IOPGAT in the study group eyes were higher than that of control group eyes (1.9 vs. 0.4 mmHg). CCT was 536.5 ± 25.4 µm (490-593 µm) in study group eyes compared with 534.2 ± 31.4 µm (472-602 µm) in control eyes (p = 0.75). Hyperparathyroidism could be associated with a decrease of CH. The differences between IOPcc and IOPGAT in these patients were higher than normal subjects. Underestimation of IOP readings with GAT may be a consequence of the lower CH in patients with hyperparathyroididsm.

Oxidant/antioxidant balance in the aqueous humor of patients with glaucoma.

AIM: To evaluate total antioxidant status (TAS), total oxidant status (TOS), and the oxidative stress index (OSI) of the aqueous humor (AH) in patients with glaucoma. METHODS: The prospective study was composed of a study group (n=31) and a control group (n=31). Fifteen patients in the study group were diagnosed with primary open angle glaucoma (POAG), and 16 patients were diagnosed with pseudoexfoliation glaucoma (PEG). The control group was composed of non-glaucomatous patients with cataracts. AH samples were collected and analyzed for TAS, TOS, and OSI levels. RESULTS: Mean AH TAS level was significantly higher in patients with glaucoma than that in the control group (P<0.01). Mean TOS and OSI levels tended to increase in patients with glaucoma. No significant differences in TAS, TOS, or OSI levels were observed between patients with POAG and PEG. CONCLUSION: High levels of TAS were observed in patients with glaucoma, which was likely a response to the increased oxidative stress observed in these patients.

Effects of commonly used intravitreal anti-vascular endothelial growth factor drugs on mesenchymal stem cells derived from the limbus and ciliary body.

BACKGROUND: To investigate the effects of commonly used intravitreal anti-vascular endothelial growth factor (anti-VEGF) antibodies on proliferation index and viability of mesenchymal stem cells derived from ciliary body and limbus (CB-MSC and LMSC). METHODS: CB-MSCs and LMSCs were isolated from newborn rats' eyes, and they were expanded in medium by the explant method. Intravitreally used anti-VEGF drugs, aflibercept, bevacizumab and ranibizumab were tested into the 16-well plates, respectively, at four different concentrations. After keeping them for 48 h, the proliferation indexes and viabilities of CB-MSCs and LMSCs were compared separately by Real-Time Cell Analyzer and Methylthiazoltetrazoli (MTT) test. RESULTS: Anti-VEGFs used at 5-times and 10-times of the standard clinical dosage caused statistically significant negative effects on proliferation indexes of CB-MSCs and LMSCs at the 24th hour compared to control group. Only the anti-VEGF group that had 10-times dosage of those used clinically had a statistically significant negative effect on the viabilties of CB-MSCs and LMSCs. CONCLUSION: Administrations of high doses or repeated standard doses of intravitreal anti-VEGF agents may affect the proliferation indexes and viabilities of CB-MSCs and LMSCs adversely. These novel findings deserve further in vivo investigations.

Isolated Microspherophakia Presenting with Angle-Closure Glaucoma.

We report a case of 13-year-old girl presenting to our clinic with blurred vision in both eyes. Ophthalmic examination revealed high myopia and angle-closure glaucoma due to pupillary block caused by small, spherical crystalline lenses. Treatment approaches to glaucoma in patients with microspherophakia are discussed in this case report.

Histopathological Analysis of Internal Limiting Membrane Surgically Peeled From Eyes with Epiretinal Membrane.

PURPOSE: To investigate histopathological changes of internal limiting membrane (ILM) in patients with epiretinal membrane (ERM) Materials and Methods: Forty-two eyes of 42 patients who were diagnosed as ERM and enrolled for vitreoretinal surgery were included in this study. Brilliant Blue G (BBG) was used to stain the ILM in all patients. ILM was peeled in all subjects and analyzed by light microscopy (methylene blue-Azur II × 40). ILM samples were then fixed in 2.5% glutaraldehyde solution and examined in JEOL-JEM 1400 and 2100F electron microscope and photographed by CCD camera (Gatan Inc., Pleasanton, CA). RESULTS: Remained ERM fragments were observed on 80% of ILM's. Vacuolization of ILM was observed in a patient with diabetic ERM. There were cells and cellular fragments observed mostly at retinal side of ILM which was likely to be a fragment of Muller cells of retina. CONCLUSIONS: Most of the ILM's had residual ERM tissue and contained cells and cellular fragments at retinal side of ILM's. ILM peeling might have a role in decreasing ERM recurrence by removal of residual ERM tissues.

The effects of commonly used intravitreal steroids on proliferation index of ciliary body-derived mesenchymal stem cells: an in vitro study.

AIM: To investigate the effects of commonly used intravitreal steroids on survival and proliferation (namely, proliferation index) of ciliary body-derived mesenchymal stem cells (CB-MSC). METHODS: CB-MSCs were isolated from newborn rats' eye, and they were expanded in the medium. Commonly used intravitreal steroids such as dexamethasone (Dex) and triamcinolone acetonide (TA) were added into the medium at commonly used concentration in clinical practice (0.1 mg/mL) and at lower concentration (0.01 mg/mL). Proliferation indexes of CB-MSCs were analyzed with the xCELLigence system at nine consecutive times (at 3rd, 6th, 21th, 30th, 45th, 60th, 75th, 90th and 100th h). RESULTS: Both TA and Dex at both 0.01 mg/mL and 0.1 mg/mL concentrations had negative effect on proliferation indexes of CB-MSC. Although negative effect of TA on proliferation index of CB-MSC at both concentrations was not statistically significant, statistically significant negative effect of Dex at 0.01 mg/mL concentration started 60th h (p = 0.017) and 0.1 mg/mL concentration started 30th h (p = 0.014). DISCUSSION: Even therapeutic doses of intravitreal corticosteroid agents might have negative effects on limited numbers of stem cells. Especially, Dex caused statistically significant toxic effects on CB-MSCs even at lower concentrations of those used clinically. These novel findings deserve further in vivo investigations.

23-gauge vitrectomy and silicone oil tamponade with and without phacoemulsification in rhegmatogenous retinal detachment.

The aim of this study is to assess clinical outcomes of 23-gauge vitrectomy and silicone oil (SO) tamponade combined with and without phacoemulsification (PE) in rhegmatogenous retinal detachment (RRD). The study included forty eyes of 40 patients that underwent 23-gauge vitrectomy and SO tamponade combined with and without PE. Twenty eyes of 20 cases, of whom underwent 23-gauge vitrectomy and SO tamponade combined with PE were allocated to the group 1. Likewise, 20 eyes of 20 cases that underwent 23-gauge vitrectomy and SO tamponade alone were allocated to the group 2. Best corrected visual acuity (BCVA) between two groups was compared. There was no significant difference in BCVA between the two groups during the 6 months (P = 0.3). Recurrent retinal detachments were observed in 2 cases (10%) in both groups. There was no statistically significant difference between two groups as a point of recurrent retinal detachments (P = 1). We have found higher rates of post-vitrectomy cataract progression (45%) in the eyes with RRD who underwent 23-gauge vitrectomy and SO tamponade. Combined vitrectomy and PE is safe and effective for the patients with RRD.

Evaluation of Optical Low Coherence Reflectometry Parameters in Patients with Exfoliation Syndrome.

Purpose. To evaluate optical low coherence reflectometry (OLCR) parameters in patients with exfoliation syndrome (EXS) undergoing cataract surgery. Methods. Forty-seven eyes of 47 patients with EXS (Group 1), and 55 eyes of 55 healthy subjects (Group 2) were included in the study. Anterior chamber depth (ACD), lens thickness (LT), axial length (AL), central corneal thickness (CCT), horizontal corneal length (HCL), and pupil diameter (PD) parameters were measured by OLCR (Lenstar LS 900, Haag-Streit) and compared between groups. Shapiro-Wilk test and Mann Whitney U tests were used for statistical analyses. Results. The mean ACD, HCL, and PD values were significantly lower in EXS group than in healthy subjects (P = 0.01, P = 0.04, and P < 0.001, resp.). The mean LT was significantly higher in EXS group than in healthy subjects (P = 0.007). There was no significant difference between groups in means of AXL and CCT. Conclusions. According to OLCR measures, eyes with EXS have shallower ACD, smaller PD, thicker LT, shorter HCL, and no significantly different CCT levels.

Idiopathic bilateral bloody tearing.

Bloody tear is a rare and distinct clinic phenomenon. We report a case presenting with the complaint of recurrent episodes of bilateral bloody tearing. A 16-year-old girl presented to our clinic with complaint of bloody tearing in both eyes for 3 months. Bloody tearing was not associated with her menses. A blood-stained discharge from the punctum was not observed during the compression of both nasolacrimal ducts. Nasolacrimal passage was not obstructed. Imaging studies such as dacryocystography and gradient-echo magnetic resonance imaging (MRI) of nasolacrimal canal were normal. Intranasal endoscopic evaluation was normal. We collected samples from bloody tears two times and pathological examination was performed. Pathological analysis showed lots of squamous cells and no endometrial cells; dysplastic cells were found. Further evaluations for underlying causes were unremarkable. No abnormalities were found in ophthalmologic, radiologic, and pathologic investigations. This condition is likely a rare abnormality and the least recognized aetiology for the idiopathic phenomenon.

Effect of allogeneic limbal mesenchymal stem cell therapy in corneal healing: role of administration route.

AIMS: To investigate whether allogeneic limbal mesenchymal stem cell (LMSC) therapy affects corneal healing after a severe chemical burn and whether the route of administration of LMSCs differs in its therapeutic effect in this respect. METHODS: A total of 60 Sprague-Dawley rats with clinically proven alkali injury were divided into four equal groups (n = 15) as follows: group 1: 2 × 10(5) cells/drop LMSCs, topically applied 6 times a day for 2 days; group 2: 2.4 × 10(6) cells in 0.5 ml LMSCs, subconjunctivally applied; group 3: 2.4 × 10(6) cells in 1 ml LMSCs, intraperitoneally applied, and group 4: no LMSC treatment. The groups were compared according to grades of corneal opacity (CO), corneal neovascularization (CNV) and corneal fluorescein staining (CFS). The migration of LMSCs into the cornea and the inflammatory characteristics of the groups were evaluated with BrdU (5-bromo-2'-deoxyuridine bromodeoxyuridine) immunostaining and histopathologically in a 4-week follow-up. RESULTS: There were statistically significant differences between the LMSC-treated and control groups in each week regarding mean CO scores and in the 3rd week regarding the mean CNV and CFS scores (p < 0.05). The statistical significance was due to the differences between the topical and the control group and between the subconjunctival and the control group. BrdU+ LMSCs were seen in the corneal epithelium of the all LMSC-administered rats, and fewer inflammatory changes were observed in these rats. CONCLUSION: Allogeneic LMSC treatment, especially topical and subconjunctival administration, seems to be helpful in affecting corneal healing after a severe corneal burn.

Comparison of ocular response analyzer parameters in primary open angle glaucoma and exfoliative glaucoma patients.

AIM: We sought to identify differences in the following measures of the ocular response analyser (ORA) between primary open angle glaucoma (POAG) and exfoliative glaucoma (EXG) patients: Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg). We also sought to relate these ORA measures with central corneal thickness (CCT). MATERIALS AND METHODS: This cross-sectional study was conducted on a total of 162 individuals (46 EXG patients, 66 POAG patients and 50 healthy subjects without any ocular and systemic disease). ORA measurements were performed, and a minimum of three readings were obtained from each test subject. Groups were compared according to their ORA parameters. RESULTS: The mean CH levels of the EXG, POAG and healthy subjects were 7.6 ± 2.1, 9.1 ± 1.9 and 9.6 ± 1.7 mmHg, respectively. CH was significantly lower in the EXG patients compared to the other groups (P < 0.001).The mean CRF levels of the EXG, POAG and healthy subjects were 9.0 ± 2.0, 10.1 ± 1.7 and 9.8 ± 1.8mmHg, respectively. CRF levels in the eyes of the EXG patients were significantly lower compared to those of either the POAG patients (P = 0.005) or the healthy subjects (P = 0.03), but there was no significant difference in CRF levels between the POAG patients and the healthy subjects (P = 0.59). There was a significant positive correlation between CH and CCT in the EXG patients and healthy subjects (P < 0.001), but this correlation was not present in the POAG patients (P = 0.70). CONCLUSIONS: In this study, CH and CRF were found to be significantly reduced in the eyes of EXG patients compared to both the POAG patients and healthy subjects. Reduced CH in EXG patients might result in decreased support of peripapillary scleral structure and increased damage to the optic nerve during IOP increase.

Efficacy of topical mesenchymal stem cell therapy in the treatment of experimental dry eye syndrome model.

Purpose. The current study was set out to address the therapeutic efficacy of topically applied mesenchymal stem cells (MSCs) on dry eye syndrome (DES) induced by benzalkonium chloride (BAC) in rats. Methods. Rats were divided into two groups just after establishment of DES. Eye drops containing either bromodeoxyuridine labeled MSCs (n = 9) or phosphate buffer solution (n = 7) were topically applied once daily for one week. Schirmer test, break-up time score, ocular surface evaluation tests, and corneal inflammatory index scoring tests were applied to all rats at baseline and after treatment. All rats were sacrificed after one week for histological and electron microscopic analysis. Results. Mean aqueous tear volume and tear film stability were significantly increased in rats treated with MSCs (P < 0.05). Infiltration of bromodeoxyuridine labeled MSCs into the meibomian glands and conjunctival epithelium was observed in MSCs treated rats. Increased number of secretory granules and number of goblet cells were observed in MSCs treated rats. Conclusion. Topical application of MSCs could be a safe and effective method for the treatment of DES and could potentially be used for further clinical research studies.

Disturbed oxidant/antioxidant balance in aqueous humour of patients with exfoliation syndrome.

PURPOSE: To establish the total oxidant status (TOS), total antioxidant capacity (TAC) and oxidative stress index (OSI) of the aqueous humour in patients presenting exfoliation syndrome (EXS) without glaucoma. METHODS: The TOS, TAC and OSI of the aqueous humour of patients with EXS (group 1, n = 17) and patients without EXS (group 2, n = 25) who underwent cataract surgery were evaluated. Samples were measured spectrophotometrically using a colourimetric method. The Mann-Whitney U, independent-samples t tests, Pearson correlation and analysis of covariance tests were used in the statistical analyses. RESULTS: The mean TOS in group 1 and 2 patients was 57.6 ± 32.4 and 30.4 ± 22.6 mmol/L, respectively, which is a statistically significant difference (p = 0.001). The mean TAC level in group 1 and 2 patients was 2.3 ± 0.7 and 2.5 ± 0.7 mmol/L, respectively, and although TAC was decreased in group 1 relative to group 2, the difference was not statistically significant (p = 0.55). The mean OSI in group 1 and 2 patients was 27.4 ± 17.1 and 12.5 ± 8.3 mmol/L, respectively, with the mean OSI level statistically higher in group 1 (p = 0.03). CONCLUSION: Our findings provide evidence that the aqueous humour of EXS patients is characterised by increased oxidative stress and a disturbed oxidant/antioxidant balance. The increased oxidative stress and decreased levels of antioxidants in ocular fluids of EXS patients may play a significant role in the pathogenesis and complications of EXS.

Comparison of prednisolone acetate and loteprednol etabonate for the treatment of benzalkonium chloride-induced dry eye syndrome in rats.

PURPOSE: The aim of the current study is to compare the effects of two corticosteroids, prednisolone acetate 1% (PA) and loteprednol etabonate 0.5% (LE), for the treatment of benzalkonium chloride (BAC)-induced dry eye syndrome (DES) in rats. METHODS: DES was established by topical administration of 0.2% BAC, a commonly used preservative in ophthalmic drugs, for 1 week. Rats were divided into 3 groups just after establishment of DES: PA-treated (Group 1, n=10), LE-treated (Group 2, n=10), and vehicle-treated (Group 3, n=10). Rats were treated by topical administration of PA, LE, or vehicle twice daily for 1 week. The Schirmer test, break-up time score, Fluorescein staining, Rose Bengal staining, and inflammatory index scoring (IIS) tests were performed at all weeks. After the end of the study, eyes of the rats were enucleated and analyzed using light microscopy. RESULTS: The mean aqueous tear volume was significantly increased in both PA- and LE-treated rats (P<0.05), although decreased in vehicle-treated rats (P>0.05). Histologically, diffuse inflammatory cell infiltration was observed in vehicle-treated rats, while inflammation induced by BAC was almost completely resolved in both PA- and LE-treated groups. CONCLUSIONS: In the current study, we showed that both PA and LE are effective treatments in a rat model of BAC-induced DES, which is commonly observed in clinics. No significant differences were observed between the 2 corticosteroids in the efficacy of BAC-induced type of DES treatment.

Presence of Dry Eye in Patients with Hashimoto's Thyroiditis.

Purpose. To evaluate the tear function tests in patients with Hashimoto's thyroiditis and to compare the results with healthy subjects. Methods. A hundred and ten patients with Hashimoto's thyroiditis and 100 healthy subjects were included in this study. The presence of thyroid-associated ophthalmopathy and tear function tests were evaluated clinically. The results were first compared between the patients and the control groups and then compared between patients with NOSPECS and patients without NOSPECS. Logistic regression analyses of the risk factors for dry eye including sex, gender, free plasma thyroxine, proptosis, upper eyelid margin-reflex distance, and duration of the disease were also evaluated. Results. The mean ocular surface disease index score was significantly higher and mean Schirmer and mean tear break-up time scores were significantly lower in patients compared to control subjects. Mean Schirmer and tear break-up time scores were found to be significantly lower in patients with NOSPECS when compared to the patients without NOSPECS. Both proptosis and free plasma thyroxine levels were significantly associated with dry eye. Conclusions. Patients with Hashimoto's thyroiditis tend to develop dry eye more common than healthy subjects. Proptosis and lower free plasma thyroxine levels were found to be risk factors for the presence of dry eye.

Changes of total antioxidant capacity and total oxidant status of aqueous humor in diabetes patients and correlations with diabetic retinopathy.

AIM: To measure changes of total oxidant status (TOS) and total antioxidant capacity (TAC) of aqueous humor (AH) in diabetic retinopathy (DR) patients, and to determine if there were any differences in TOS and TAC of AH in diabetic patients without retinopathy compared with non-diabetic patients. METHODS: One hundred and three eyes of 103 patients who were enrolled for cataract surgery were included in this study. Patients were grouped according to presence of diabetes and stage of DR. Prior to cataract surgery, 0.1mL to 0.2mL of AH was aspirated and analyzed for TAC and TOS level using a colorimetric method. RESULTS: TOS levels were highest among proliferative diabetic retinopathy (PDR) patients and lowest in patients with only cataracts. Results were statistically significant between all groups (P<0.05). Whereas result between diabetic without retinopathy patients and non-proliferative diabetic retinopathy (NPDR) patients was not statistically significant (P=0.757). TAC levels were highest in patients with only cataract and lowest among PDR patients and results were statistically significant between all groups (P<0.05). CONCLUSION: Aqueous humor TAC levels are low in diabetic patients and reduced further in DR patients, TOS levels are increased in diabetic patients and this is exacerbated in DR patients.