Mustafa İlker Toker

The Prevalence of Demodex folliculorum in Blepharitis Patients and the Normal Population.

Purpose: Demodex folliculorum (DF), which is frequently found in patients with chronic blepharitis, is a well-known common inhabitant of eyelash follicles. In the present study, the prevalence of DF in seborrheic blepharitis patients and controls was investigated. In addition, the associations between the presence of DF and host factors (age, sex) were analyzed. Methods: A prospective, cross-sectional study was done involving 500 cases. In all, 6000 cilia from 170 patients with seborrheic blepharitis and 330 patients with normal eyes were examined for DF. Twelve eyelash samples were epilated from each patient and examined under the light microscope. Results: DF was found in 28.8% (49/170) of patients with blepharitis and in 26.7% (88/330) of controls. The difference between the two groups was not statistically significant. The overall prevalence was 27.4% (137/500) in all patients. Although the prevalence of DF increased with increasing age, no significant difference was found between the age groups. There was also no statistically significant difference for DF prevalence between males (28.9%; 71/246) and females (24.1%; 61/254). Conclusion: Our findings show a high DF prevalence in both blepharitis and control patients and no relationship was found between the presence of DF and host factors (age, sex).

Comparison of the effects of bevacizumab and ranibizumab injection on corneal angiogenesis in an alkali burn induced model.

AIM To investigate the effects of bevacizumab and ranibizumab on corneal neovascularization in an alkali burn-induced model of corneal angiogenesis. METHODS Fifteen Wistar albino rats were divided randomly into 3 groups after chemical cauterization of the cornea. The first group received a single dose of 0.1mL saline solution as a control group whereas second and third groups received a single dose of 2.5mg bevacizumab or 1mg ranibizumab by subconjunctival injection, respectively. After three weeks, the rat corneas were evaluated by biomicroscopy and corneal photographs were taken. The percentage of neovascularization area, length of the longest new vessel, corneal edema and corneal opacity scores were assessed. RESULTS The analysis of digital photographs showed that the percentage of neovascularization area to the total corneal area, the length of the longest new vessel, corneal edema and opacity scores were significantly lower in both study groups compared to the control group (P<0.05). Additionally, the percentage of corneal neovascularization area, the length of the longest new vessel and corneal opacity score were less with bevacizumab than ranibizumab. CONCLUSION Subconjunctival bevacizumab and ranibizumab treatments may be effective methods in reducing corneal neovascularization. Furthermore, bevacizumab is more effective than ranibizumab in the inhibition of corneal neovascularization.

The effect of propolis in experimental Acanthamoeba keratitis

Purpose:  To examine the effect of propolis in a rat model of Acanthamoeba keratitis and to determine its in vitro cytotoxicity in cultured corneal epithelial cells.

Total oxidative stress, paraoxonase and arylesterase levels at patients with pseudoexfoliation syndrome and pseudoexfoliative glaucoma

AIM To investigate the oxidative stress status of the aqueous humor and serum of patients with pseudoexfoliation (PEX) syndrome and pseudoexfoliative glaucoma (PEG) and to measure paraoxonase (PON) and arylesterase (ARE) levels. METHODS A total of 78 patients were enrolled in the study, with 26 patients in each separate group. The patients were divided into three groups: the first group entailed PEX syndrome patients, while the second group consisted of patients with PEG and the third group involved patients with no additional systemic diseases, other than the diagnosis of cataract as control. Total oxidative stress (TOS), total antioxidant capacity (TAC), PON, and ARE levels in aqueous humor and serum were measured. RESULTS TAC, PON and arylesterase levels in aqueous humor and serum of the PEX syndrome and PEG patients were significantly decreased compared with control group (P<0.05). TOS values were higher in patients with PEX syndrome and PEG than controls (P<0.05). TAC, PON and ARE levels of aqueous humor did not differ significantly between the PEX syndrome and PEG groups. CONCLUSION These findings are potentially of significance and add to the growing body of evidence for oxidative stress in PEX syndrome and PEG. Decreased antioxidant defense and increased oxidative stress system may play an important role in the pathogenesis of PEX syndrome and PEG.

The Association between Diabetic Retinopathy and Levels of Ischemia-Modified Albumin, Total Thiol, Total Antioxidant Capacity, and Total Oxidative Stress in Serum and Aqueous Humor.

Purpose. To investigate the oxidant and antioxidant status of patients with type 2 diabetes mellitus and nonproliferative diabetic retinopathy (DRP). Methods. Forty-four patients who had cataract surgery were enrolled in the study. We included 22 patients with DRP in one group and 22 patients in the control group. Samples of aqueous humor and serum were taken from all patients. Serum and aqueous ischemia-modified albumin (IMA), total thiol, total antioxidant capacity (TAC), and total oxidative stress (TOS) levels were compared in two groups. Results. Median serum IMA levels were 44.80 absorbance units in the DRP group and 40.15 absorbance units in the control group (P = 0.031). Median serum total thiol levels in the DRP group were significantly less than those in the control group (3051.13 and 3910.12, resp., P = 0.004). Mean TOS levels in the serum were 2.93 ± 0.19 in the DRP group and 2.61 ± 0.26 in the control group (P = 0.039). The differences in mean total thiol, TAC, and TOS levels in the aqueous humor and mean TAC levels in the serum were not statistically significant. Conclusion. IMA, total thiol, and TOS levels in the serum might be useful markers in monitoring the risk of DRP development.

Effect of latanoprost/timolol and dorzolamide/tiomolol on intraocular pressure after phacoemulsification surgery

AIM To evalaute the effect of fixed-combination latanoprost 0.005%/timolol maleate 0.5% and dorzolamide hydrochloride 2%/timolol maleate 0.5% on postoperative intraocular pressure after phacoemulsification cataract surgery. METHODS This study is a prospective, randomized, double-masked and placebo-controlled. The study included 90 eyes of 90 patients which were scheduled to have phacoemulsification surgery. Patients were randomly assigned preoperatively to 1 of 3 groups (30 eyes of 30 patients). Two hour before surgery, the patients received one drop latanoprost/timolol (group 1), dorzolamide/timolol (group 2) and placebo (group 3, control group). The IOPs were measured at preoperative and postoperative 4, 8, and 24 hours. RESULTS The preoperative mean intraocular pressure was not statistically significant between both drug groups and control group. In group 1 and 2, the postoperative mean IOP [group1: (14.03±3.15)mmHg and group 2: (14.16±4.43)mmHg] at 24 hours were significantly lower than the control group [(16.93±3.70)mmHg, (P<0.05)]. In addition, the postoperative mean IOP of group 1 [(14.90±3.69)mmHg] at 8 hours was significantly lower than the control group [(17.70±3.89)mmHg, (P<0.05)], but there was no significant difference between group 2 [(16.16±5.23)mmHg] and control group at 8 hours (P>0.05). CONCLUSION When compared with placebo, the use of preoperative fixed combination of latanoprost/timolol and dorzolamide/timolol is an effective method for preventing intraocular pressure elevation in 24 hours after phacoemulsification surgery, but did not completely prevent IOP spikes.

Nifedipine Enhances the Relaxant Effects of Cyclo-Oxygenase Inhibitors on the Bovine Ciliary Muscle

BACKGROUND/AIMS The inhibition of cyclo-oxygenase (COX) enzymes and the blockade of Ca (2+) channels play an important role in the regulation of smooth muscle relaxation. This study was designed to investigate the relaxant effects of celecoxib, DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone), and indomethacin, cyclo-oxygenase (COX-1 and -2) inhibitors, in the absence or presence of a nifedipine, L-type Ca(2+) channel blocker, on bovine ciliary muscle. METHODS Ciliary muscle strips (n = 12) were mounted in organ baths and tested for changes in isometric tension in response to celecoxib, DFU, and indomethacin. The relaxant effects of celecoxib, DFU, and indomethacin on carbachol-induced contractions in the presence or absence of nifedipine were investigated. RESULTS Celecoxib (10(-7)-10(-4) M), DFU (10(-7)-10(-4) M), indomethacin (10(-7)-10(-4) M), and nifedipine (10(-7)-10(-4) M) inhibited the carbachol-induced contractions in a concentration-dependent manner. The E(max) value of indomethacin was significantly higher than the E(max) values of celecoxib and DFU in ciliary muscle (P < 0.05), with no significant change in pD(2) values (P > 0.05). The relaxation responses by celecoxib, DFU, and indomethacin were significantly increased in the presence of nifedipine (10(-6) M). There were no significant differences between pEC50 and values of celecoxib, DFU, and indomethacin in the absence of nifedipine (10(-6) M) (P > 0.05), but E(max)values were significantly increased (P < 0.05). CONCLUSIONS These results suggest that the celecoxib, DFU, and indomethacin cause relaxation in ciliary muscle precontracted with carbachol. Blockade of calcium channels with nifedipine in ciliary muscle may increase the relaxant effect of celecoxib, DFU, and indomethacin. The topical or systemic use of celecoxib, DFU, and indomethacin with nifedipine can cause blurred near vision due to ciliary muscle relaxation, and in ocular pain conditions caused by ciliary spasm, the pain can be decreased more easily by combined use of these drugs.

Association of neutrophil/lymphocyte ratio and retinal vein occlusion

Purpose To evaluate the association between neutrophil/lymphocyte ratio (NLR) and the development of retinal vein occlusion (RVO). Methods Forty patients were included in the study. Forty age- and sex-matched healthy volunteers were recruited as the control group. The RVO diagnosis was made clinically, based on the findings of fundus examination. The NLR and file records of the patients and the control group were compared. Results The mean age of patients was 64 ± 12 years. Neutrophil levels were higher in RVO patients compared to the control subjects (5.1 ± 1.9 vs 3.6 ± 1.0, p<0.001). Lymphocyte levels were lower in RVO patients compared with the control subjects (2.0 ± 0.7 vs 2.6 ± 0.9, p = 0.005). The NLR was significantly higher in RVO patients compared with the control subjects (3.0 ± 2.7 vs 1.5 ± 0.3, p<0.001). According to the receiver operator characteristics curve analysis, the optimal cutoff value of NLR to predict RVO was >1.89, with 72.5% sensitivity and 100% specificity. Conclusions The current study demonstrated that higher NLR was associated with the development of RVO. The NLR may be used as a predictive tool for identifying risk for RVO.

Apoptotic effects of topical antiglaucoma medications on conjunctival epithelium in glaucoma patients.

Purpose In this study, we aimed to investigate the apoptotic effects of topical antiglaucoma medications on the conjunctival epithelium. Methods A total of 65 patients were included in the study. Thirty patients were included in the first group who had received antiglaucomatous therapy before trabeculectomy. In the second group, 20 patients who had received no drugs before trabeculectomy were included, while the third group underwent only cataract surgery as control. During the surgery, 2 × 4 mm conjunctival samples were harvested from the upper bulbar conjunctiva. The mean apoptosis rate was calculated by determining apoptosis at conjunctival epithelium using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) method. Results The mean apoptosis rate was 0.537 ± 0.369 (0.026 ± 0.962) in group 1, 0.139 ± 0.162 (0.005 ± 0.676) in group 2, and 0.078 ± 0.035 (0.035 ± 0.142) in the control group (group 3). The mean apoptosis rate was significantly higher in the first group than the other 2 groups (p = 0.0001). Conclusions Apoptotic effects of topical antiglaucoma drugs on the conjunctival epithelial cells were found. However, our results revealed that the number of medications, duration of medication, and type of glaucoma had no effect on the apoptotic effect.

Evaluation of Choroidal Thickness in Patients with Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma

Purpose. To compare the macular and peripapillary choroidal thickness in eyes with pseudoexfoliation (PEX) syndrome and PEX glaucoma with the normal eyes of healthy controls. Materials and Methods. In this prospective study, 30 eyes of 30 patients with PEX syndrome, 28 eyes of 28 patients with PEX glaucoma, and 30 eyes of 30 age-matched healthy subjects were enrolled. Choroidal thicknesses in the macular and peripapillary areas were measured by using spectral domain optical coherence tomography. Results. Gender, age, and axial length did not significantly differ between the groups (all, p > 0.05). The mean values of choroidal thickness in the macular and peripapillary areas (except the superior quadrant) in the patients with PEX syndrome and PEX glaucoma were lower compared with controls (all p < 0.05). The mean values of the macular and peripapillary choroidal thickness in the PEX glaucoma group were lower compared with PEX syndrome group; however this difference was not significant. Conclusions. The findings of this study revealed that macular and peripapillary choroidal thicknesses were decreased in PEX syndrome and PEX glaucoma cases. The role of choroid in the development of glaucomatous damage in patients with PEX syndrome remains unclear.