Ismail Ersan

Protective Effect of Hesperetin and Naringenin against Apoptosis in Ischemia/Reperfusion-Induced Retinal Injury in Rats

Purpose. Hesperetin and naringenin are naturally common flavonoids reported to have antioxidative effects. This study was performed to investigate whether either hesperetin or naringenin has a protective effect against apoptosis on retinal ischemia/reperfusion (I/R) injury. Methods. Retinal I/R was induced by increasing the intraocular pressure to 150 mmHg for 60 minutes. Thirty-three male Wistar albino rats were randomised into 5 groups named control, I/R + sham, I/R + solvent (DMSO), I/R + hesperetin, and I/R + naringenin. Animals were given either hesperetin, naringenin, or the solvent intraperitoneally immediately following reperfusion. Thickness of retinal layers and retinal cell apoptosis were detected by histological analysis, tunel assay, and immunohistochemistry assay. Results. Hesperetin and naringenin attenuated the I/R-induced apoptosis of retinal cells in the inner and outer nuclear cells of the rat retina. Retinal layer thickness of the naringenin treatment group was significantly thicker than that of the hesperetin, sham, and solvent groups (P < 0.05). Conclusions. Hesperetin and naringenin can prevent harmful effects induced by I/R injury in the rat retina by inhibiting apoptosis of retinal cells, which suggests that those flavanones have a therapeutic potential for the protection of ocular ischemic diseases.

Quercetin protects the retina by reducing apoptosis due to ischemia-reperfusion injury in a rat model

PURPOSE This study aimed to investigate the effect of quercetin on apoptotic cell death induced by ischemia-reperfusion (I/R) injury in the rat retina. METHODS Twenty-four rats were divided into four equal groups: control, ischemic, solvent, and quercetin. I/R injury was achieved by elevating the intraocular pressure above the perfusion pressure. Intraperitoneal injections of 20 mg/kg of quercetin and dimethyl sulfoxide (DMSO) were performed in the quercetin and solvent groups, respectively, immediately prior to I/R injury, and the researchers allowed for the retinas to be reperfused. Forty-eight hours after injury, the thicknesses of the retinal ganglion cell layer (RGCL), inner nuclear layer (INL), inner plexiform layer (IPL), outer plexiform layer (OPL), and outer nuclear layer (ONL) were measured in all groups. Moreover, the numbers of terminal deoxynucleotidyl transferase dUTP nick-end-labeled [TUNEL (+)] cells and caspase-3 (+) cells in both INL and ONL were evaluated in all groups. RESULTS The administration of quercetin was found to reduce the thinning of all retinal layers. The mean thickness of INL in the quercetin and ischemic groups was 21 ± 5.6 µm and 16 ± 6.4 µm, respectively (P<0.05). Similarly, the mean thickness of ONL in the quercetin and ischemic groups was 50 ± 12.8 µm and 40 ± 8.7 µm, respectively (P<0.05). The antiapoptotic effect of quercetin in terms of reducing the numbers of both TUNEL (+) cells and caspase-3 (+) cells was significant in INL. The mean number of TUNEL (+) cells in INL in the ischemic and quercetin groups was 476.8 ± 45.6/mm2 and 238.72 ± 251/mm2, respectively (P<0.005). The mean number of caspase-3 (+) cells in INL of ischemic and quercetin groups was 633.6 ± 38.7/mm2 and 342.4 ± 36.1/mm2, respectively (P<0.001). CONCLUSION The use of quercetin may be beneficial in the treatment of retinal I/R injury because of its antiapoptotic effect on the retinal layers, particularly in INL.

Evaluation of Retinal Nerve Fiber Layer Thickness in Patients With Anisometropic and Strabismic Amblyopia Using Optical Coherence Tomography

PURPOSE To evaluate the retinal nerve fiber layer (RNFL) thickness of eyes with amblyopia using optical coherence tomography (OCT). METHODS RNFL thickness measurements obtained by time-domain OCT of amblyopic eyes of patients with strabismus (35 patients) and patients with anisometropia (30 patients) were compared with their fellow eyes and age- and gender-matched healthy eyes (40 participants). RNFL thickness values of the groups were also compared and the correlation between RNFL thickness and refraction was evaluated. RESULTS In the strabismic and anisometropic groups, there were no statistically significant differences in average RNFL thickness between amblyopic eyes and their fellow eyes (P > .05). Temporal RNFL quadrant in the hypermetropic anisometropic group, and superior RNFL quadrant in the myopic anisometropic group were significantly thinner in amblyopic eyes compared to their fellow eyes (P < .05). RNFL thickness did not differ between strabismic amblyopic, anisometropic amblyopic, and control eyes (P > .05). In the anisometropic group, a significant correlation was found between mean RNFL thickness and refraction (P < .05). CONCLUSION Amblyopia is not associated with a decrease in RNFL thickness in strabismic or anisometropic amblyopia. In the anisometropic group, the inter-eye differences in RNFL thickness parameters seemed to be related to the refraction differences between the amblyopic eyes and their fellow eyes.[J Pediatr Ophthalmol Strabismus 2013;50:113-117.].

Effect of Topically Applied Azithromycin on Corneal Epithelial and Endothelial Apoptosis in a Rat Model of Corneal Alkali Burn.

Purpose: To investigate the antiapoptotic effect of topically administered azithromycin (AZM) on corneal epithelial and endothelial cells in a rat model of corneal alkali burn. Methods: Twenty-four Wistar albino rats were divided into 4 equal groups as pseudovehicle (group 1), control (group 2), alkali burned (group 3), and treatment (group 4) groups. Alkali injury was induced only in the right corneas of rats belonging to groups 3 and 4 using 1N NaOH. The rats in group 3 and the rats in group 4 were respectively treated either with an artificial tear gel or with 1.5% AZM eye drops for 5 days. At the fifth day of the experiment, the apoptosis in the corneal epithelium and endothelium of all rats was assessed using a terminal dUTP nick-end labeling (TUNEL) assay. In addition, tumor necrosis factor-alpha (TNF-&agr;) density in the corneal epithelium was measured in all rats. Results: The mean numbers of TUNEL+ cells in the corneal epithelium and endothelium of rats in group 3 were 117.1 ± 23.8 and 34.6.± 11.3, respectively, whereas in group 4, they were 75.8 ± 15.7 and 14.7 ± 3.5, respectively. Also the mean TNF-&agr; densities in the corneal epithelium in group 3 and group 4 were 2.65 ± 1.3 and 1.65 ± 1.1, respectively. There was a significant decrease in the mean number of TUNEL+ cells in the corneal epithelium and endothelium and in the mean TNF-&agr; density in the corneal epithelium of rats in group 4, when compared with group 3. Conclusions: Topically applied AZM can decrease TNF-&agr;–induced apoptosis in corneal alkali burn.

Evaluation of Macular Ganglion Cell-inner Plexiform Layer and Choroid in Psoriasis Patients Using Enhanced Depth Imaging Spectral Domain Optical Coherence Tomography

ABSTRACT Purpose: To evaluate changes in the thickness of the central macula, macular ganglion cell-inner plexiform layer (mGCIPL), and subfoveal choroid in patients with psoriasis using spectral domain optical coherence tomography (SD-OCT). Methods: The measurements of macular, mGCIPL thicknesses and subfoveal choroidal thickness (SFCT) obtained by SD-OCT of psoriasis patients (n = 46). These measurements were compared with those of 50 healthy controls. Results: The macular, mGCIPL, and choroidal thicknesses did not differ between the controls and psoriatic subjects (p>0.05). When the patients were divided into two distinct groups, only the SFCT was significantly thicker in the severe psoriasis group compared with the mild psoriasis group (p = 0.003). Conclusions: These findings suggest that choroidal alterations are seen without macular changes in patients with psoriasis. Severe psoriasis appears to be related to increases in SFCT as a consequence of possible inflammatory cascades that are part of the disease’s pathogenesis.

The Effect of Dehydration and Fasting on Corneal Biomechanical Properties and Intraocular Pressure.

Purpose: To evaluate the changes in corneal biomechanical properties and intraocular pressure (IOP) during fasting period in healthy subjects. Methods: Seventy-two eyes of 72 fasting subjects (study group), and 62 eyes of 62 nonfasting subjects (control group) were enrolled in this prospective study undertaken at a single university hospital. All subjects underwent complete ophthalmologic examination including ocular biomechanical evaluation with ocular response analyzer. Ocular response analyzer measurement was performed on the right eyes of the subjects between 5.00 and 6.00 PM after approximately 14 hr of fasting for the study group and after a nonfasting period for the control group. The corneal hysteresis, corneal resistance factor, mean corneal compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) values were measured with a patented dynamic bidirectional applanation process. Results: Goldmann-correlated IOP and IOPcc measurements in the study group and the control group were found as 13.8±2.8 mm Hg, 14.6±2.6 mm Hg and 16.3±2.2 mm Hg, 15.7±2.4 mm Hg, respectively. There was statistically significant difference within the two groups in IOPg and IOPcc (P<0.001). In addition, corneal hysteresis and corneal resistance factor significantly decreased in study group compared with control group (P<0.001, P=0.012, respectively). Conclusion: Prolonged fasting causes a significant decrease in IOPg, IOPcc, corneal hysteresis, and corneal resistance factor in healthy subjects, altering the biomechanical properties of the cornea.

Intraocular lens explantation or exchange: indications, postoperative interventions, and outcomes

PURPOSE To analyze the indications for explantation or exchange of intraocular lenses (IOLs), which were originally implanted for the correction of aphakia during cataract extraction. METHODS All cases that involved intraocular lens explantation or exchange in one institution between January 2008 and December 2014 were analyzed retrospectively. RESULTS In total, 93 eyes of 93 patients were analyzed. The median time interval between implantation and explantation of the anterior chamber intraocular lenses (AC IOL) and posterior chamber intraocular lenses (PC IOL) was 83.40 ± 83.14 months (range: 1-276 months) and 55.14 ± 39.25 months (range: 1-168 months), respectively. Pseudophakic bullous keratopathy (17 eyes, 38.6%) and persistent iritis (12 eyes, 27.8%) in the AC IOL group and dislocation or decentration (30 eyes, 61.2%) and incorrect IOL power (nine eyes, 18.4%) in the PC IOL group were the most common indications for explantation of IOLs. The mean logMAR best corrected visual acuity (BCVA) improved significantly from 1.30 preoperatively to 0.62 postoperatively in the PC IOL group (p<0.001) but did not improve significantly in the AC IOL group (p=0.186). CONCLUSIONS The primary indication for IOL explantation or exchange was pseudophakic bullous keratopathy in the AC IOL group and was dislocation or decentration in the PC IOL group. PC IOL explantation or exchange is safe and improves visual acuity.

Simplified Technique for Sealing Corneal Perforations Using a Fibrin Glue-Assisted Amniotic Membrane Transplant-Plug

Purpose. To describe a surgical technique using amniotic membrane transplant (AMT) with fibrin glue (FG) for treating smaller corneal perforations more practically and appropriately filling the defect. Method. A patient with noninfectious central corneal perforation, in 1 mm in diameter, was treated with FG-assisted AMT-plug. An AMT was folded in on itself twice by using FG then a small piece of this FG-AMT mixture was cut to maintain an appropriate plug for the site of the corneal perforation. The FG-assisted AMT-plug was placed in the perforation area by using FG. An amniotic membrane patch was placed over the plug, which was then secured by a bandage contact lens. Result. Surgery to restore corneal stromal thickness without recurrence of perforation. Conclusion. The FG-assisted AMT-plug allowed a successful repair of 1 mm in diameter corneal perforation. This technique was easily performed, thus seeming to be a good alternative to treat corneal perforations with restoring corneal thickness.

The Effect of Smoking on Corneal Endothelial Cells

ABSTRACT Purpose: To investigate the effect of chronic cigarette smoking on the endothelial cells of the cornea via non-contact specular microscopy. Method: In this prospective, cross-sectional study, 25 eyes of 25 chronic smokers and 21 eyes of 21 age-matched, healthy non-smokers were enrolled. The Fagerström Test for Nicotine Dependence on Cigarettes was used to determine the nicotine dependency level. The level of cotinine, a major metabolite of nicotine, was measured in urine samples from the control group to detect whether they were passively affected by cigarette smoke. All participants underwent measurement of tear break-up time (TBUT), central corneal thickness (CCT), and axial length. Endothelial cell density and endothelial cell morphology were evaluated by non-contact specular microscopy. Results: On average, the cigarette smokers consumed 19.2 ± 8.3 cigarettes per day and had been smoking for 14.5 ± 6.8 years. The mean TBUT value was significantly lower in the smoker group compared to the non-smoker group (p < 0.05). No statistically significant difference was found in the mean CCT, mean endothelial cell density, or parameters of endothelial cell morphology between smokers and non-smokers. Conclusion: This study showed that cigarette smoking seems to affect the TBUT value but no effects were found on the parameters of corneal endothelial cells.

Non-invasive assessment of corneal and conjunctival deterioration in soft contact lens users using anterior segment optical coherence tomography

The aim was to evaluate the corneal and bulbar conjunctival thicknesses of soft contact lens (SCL) wearers using anterior segment optical coherence tomography (AS‐OCT).