Metin Unlu

Effect of corneal cross-linking on contact lens tolerance in keratoconus

The aim was to investigate changes in corneal sensation and rigid gas‐permeable (RGP) contact lens tolerance after corneal cross‐linking (CXL) on patients with keratoconus.

Congenital glaucoma as an ophthalmic manifestation of Frank–Ter Haar syndrome

We report on a patient with Frank–Ter Haar syndrome that is associated with high intraocular pressures. A 21-day-old male patient was referred to our clinic for surgical treatment of congenital glaucoma. On ophthalmic examination, he had buphthalmos, mild corneal edema and high IOP readings in both eyes. The patient underwent uneventful trabeculotomy surgery, bilaterally. Marked bilateral anterior iris insertion was noted during the surgery. Childhood glaucoma may be associated with Frank–Ter Haar syndrome.

The effect of systemic erythropoietin treatment on retinal nerve fiber layer parameters in patients with chronic renal failure undergoing peritoneal dialysis.

Purpose:To evaluate the effect of erythropoietin (EPO) treatment on retinal nerve fiber layer (RNFL) parameters in patients with chronic renal failure (CRF) undergoing peritoneal dialysis (PD). Methods:Fifty-eight eyes of 29 patients with CRF undergoing PD were evaluated. Fifteen patients have been treated with EPO (group 1), 14 patients without EPO treatment (group 2), and 30 eyes of 15 age-matched normal control subjects were assessed in group 3. A complete ophthalmologic examination and RNFL measurements were performed for each patient after PD. Anemia parameters were also measured. RNFL thickness protocol was used to acquire circular scans of 3.4 mm in diameter around optic nerve. RNFL thicknesses were evaluated in 4 quadrants. Only the left eyes were recruited for statistical analysis. The mean and quadrantal RNFL thickness values in group 1 were compared with those of groups 2 and 3. Results:The mean RNFL thickness values in patients undergoing PD were statistically lower than the control group at superior, inferior, nasal, and temporal quadrant, respectively (P=0.03, 0.04, 0.04, and 0.03). Differences between the RNFL thickness values in group 1 and group 2 were statistically significant only in the temporal quadrant (P=0.02). Conclusions:In patients with CRF undergoing PD, RNFL thickness parameters were found to be significantly reduced. The effect of EPO on RNFL parameters was statistically significant only in the temporal quadrant.

The role of intraoperative bevacizumab for prevention of postoperative vitreous hemorrhage in diabetic vitreous hemorrhage.

Purpose To assess the effect of intravitreal bevacizumab (IVB) on the incidence of postoperative recurrent vitreous hemorrhage (VH) in eyes operated for diabetic VH when injected at the end of the surgery. Methods A prospective, comparative clinical trial was conducted on a consecutive series of patients requiring vitrectomy for diabetic nonclearing VH. Intravitreal bevacizumab (2.5 mg/0.1 mL) was injected at the completion of surgery. Patients underwent best-corrected visual acuity (VA), applanation tonometry, and biomicroscopic anterior and posterior segment evaluation for VH grading. Postoperative visits were performed at the first day, first week, first month, third month, and sixth month. The VH was graded at each visit, and the rate of postoperative VH and VA improvement and potential complications were evaluated and compared between the groups. Results A total of 72 eyes of 66 patients were included. Thirty-four eyes were enrolled in the IVB group and 38 eyes were enrolled in the control group. The rate of postoperative VH did not differ significantly between the groups at any postoperative visit (p>0.05). Three eyes (8.8%) in the IVB group and 5 eyes (13.1%) in the control group had postoperative VH throughout the follow-up period and only one eye from each group underwent a second surgery. Postoperative VA significantly increased in both groups but did not differ significantly between the groups at any postoperative visit (p>0.05). Conclusions Intravitreal bevacizumab does not seem to have any beneficial effect on the incidence of postoperative VH in eyes operated for diabetic VH when injected at the end of surgery.

Neuroprotective effect of systemic and/or intravitreal rosuvastatin administration in rat glaucoma model.

AIM To evaluate the neuroprotective effect of rosuvastatin, in a rat experimental glaucoma model. METHODS Ocular hypertension was induced in right eyes of Long-Evans rats (n=30) by cauterization of three episcleral veins. Left eyes were defined as controls. Rats were divided into five groups: oral rosuvastatin, intravitreal rosuvastatin, oral+intravitreal rosuvastatin, intravitreal sham and glaucoma without intervention. Rats were sacrificed at day 14. Retinal ganglion cell (RGC) number was assessed by histopathological analysis. Terminal deoxynucleotidyl transferase-mediated dUTP-nick end-labeling (TUNEL) staining and the expression of glial fibrillary acidic protein (GFAP) in RGC layer was also examined. RESULTS A significant intraocular pressure (IOP) elevation was seen (P=0.002). Elevated IOP resulted in a significant decrease in number of RGCs in group 5 (70.33±8.2 cells/mm(2)) when compared with controls (92.50±13.72 cells/mm(2); P=0.03). The RGC number in group 1 (92.4±7.3 cells/mm(2)) was significantly higher than group 5 (P=0.03). The numbers of RGC in groups 2, 3 (57.3±8.2 cells/mm(2), 60.5±12.9 cells/mm(2)) were comparable with that of group 5 (P=0.18 and P=0.31). The apoptosis rates with TUNEL staining were also parallel to RGC number. Animals with experimentally induced glaucoma showed an increase in retinal GFAP immunoreactivity. CONCLUSION Decrease in RGC loss and apoptosis suggest the neuroprotective potential of oral rosuvastatin treatment in a rat model of ocular hypertension. However intravitreal rosuvastatin showed a contrary effect and further studies are required.

The Effects of Anti-Vascular Endothelial Growth Factor Drugs on Retinal Pigment Epithelial Cell Culture

Objectives: To assess the effects of anti-vascular endothelial growth factor (VEGF) drugs on retinal pigment epithelium cell culture. Materials and Methods: Aflibercept (0.5 mg/mL), bevacizumab (0.3125 mg/mL), and ranibizumab (0.125 mg/mL) were applied to retinal pigment epithelium cell cultures isolated from the enucleated eyes of New Zealand white rabbits. Viability, apoptosis, proliferation, and senescence of the cells were evaluated in control and drug-treated cultures at the end of 72 hours. Results: Cells treated with aflibercept showed increased viability and decreased apoptosis compared to the control culture and both the bevacizumab- and ranibizumab-treated groups (p<0.05). Statistically increased apoptosis and decreased viability were found in the bevacizumab and ranibizumab-treated groups compared with the control group (p<0.05). There were no statistically significant differences in cell proliferation and senescence between the groups (p>0.05). Conclusion: Anti-VEGF drugs did not affect senescence or proliferation of retinal pigment epithelium cells. Aflibercept was found to decrease apoptosis and increase cell viability, while ranibizumab and bevacizumab increased apoptosis and reduced cell viability in retinal pigment epithelium culture.

Correlations among multifocal electroretinography and optical coherence tomography findings in patients with Parkinson’s disease

To assess the correlation between functional and anatomical evaluations with multifocal electroretinography (mfERG) and spectral-domain optical coherence tomography (SD-OCT) in patients with Parkinson’s disease (PD). This cross-sectional study involved 116 eyes of 58 patients with PD and 30 age- and sex-matched control subjects. All study participants underwent a comprehensive neuro-ophthalmic examination, retinal single-layer thicknesses and volumes, and peripapillary retinal nerve fiber layer (pRNFL) measurements with SD-OCT, and the patients’ mfERG recordings were evaluated. The macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), outer nuclear layer (ONL), retinal pigment epithelium (RPE), and photoreceptor layer (PR) thicknesses, and mRNFL, RPE, and PR volumes were found lower in PD compared to those of controls, while outer plexiform layer (OPL) volumes were increased (p < 0.05). We found delayed implicit times and decreased amplitudes in the mfERG of PD patients versus those in control subjects (p < 0.05). We found significant correlations between outer macular volumes, PR thicknesses, and N1 amplitudes of rings 2 and 3and P1 amplitudes of rings 3, 4, and 5. Our study revealed thinning of both inner and outer retinal single layers, increased OPL volume, and delayed implicit times and decreased amplitudes in the mfERG of PD patients versus control subjects and correlation between structural and functional parameters. Our findings point out that SD-OCT and mfERG could both serve as non-invasive tools for evaluating ophthalmic manifestations of Parkinson’s disease.

Ocular complications of severe corneal abrasions after cosmetic blepharopigmentation

ABSTRACT A 53-year-old woman with hemiparesis and poor dexterity, underwent cosmetic blepharopigmentation on the both upper eyelids in the dermatology clinic of a private hospital. She was not asked for any information on her medical history and no informed consent was obtained and the procedure was performed without any protective ocular shields. The patient experienced severe lacrimation, discomfort, and increased sensitivity to light during and after the procedure. She also noticed blurred vision after the procedure. Ophthalmologic examination revealed tender and oedematous eyelids and corneal abrasions in both of her eyes. Topical antibiotics and preservative-free lubricants were able to recover her from her signs and symptoms at 1-week follow-up. It is recommended that cosmetic blepharopigmentation should be applied cautiously with patient’s informed consent after obtaining a thorough medical history and with protective ocular shields to avoid potential complications.

Ocular complications after cosmetic periocular diode laser application to the eyelids

ABSTRACT A 25-year-old woman underwent diode laser application on the both upper eyelids in the dermatology department of a private hospital to obtain a cosmetic healing of the reddish look on her eyelids without any protective lenses. The patient experienced severe uveitis, atonic pupils, raised intraocular pressure, and increased sensitivity to light in her eyes on the following day of the procedure. Topical steroids and pressure-lowering agents were able to treat the acute uveitis and glaucoma, unfortunately the patient suffered from irreversible atonic and atrophic pupils and photosensitivity. It is recommended that cosmetic laser application on the periocular area should be avoided, and if it is still to be performed, it should be applied cautiously and the patient should be informed of the potential ocular complications.

Autologous serum eye‐drops and enhanced epithelial healing time after photorefractive keratectomy

The aim of the study is to test whether use of autologous serum eye‐drops can provide earlier epithelial healing following the application of photorefractive keratectomy.