Adnan Aksoy

The results of switching between 2 anti-VEGF drugs, bevacizumab and ranibizumab, in the treatment of neovascular age-related macular degeneration.

Purpose To report the results of switching from intravitreal bevacizumab to ranibizumab or vice versa in the treatment of choroidal neovascularization (CNV) due to age-related macular degeneration. Methods Twenty eyes of 18 patients that underwent switch from intravitreal bevacizumab to ranibizumab and 10 eyes of 8 patients that underwent switch from ranibizumab to bevacizumab were retrospectively analyzed. The results were compared with 41 eyes of 37 patients treated with ranibizumab only. All eyes initially received 3 injections of ranibizumab or bevacizumab, which were repeated as needed (PRN dosing). Anti–vascular endothelial growth factor therapies were switched because of general health insurance applications and cost problems. The main outcome measures were best-corrected visual acuity (BCVA), injection number, and central macular thickness (CMT) obtained by optical coherence tomography. Results Once all patients evaluated together at the final visit, the mean BCVA improved and CMT decreased. When switching groups were taken into consideration, switching yielded improved BCVA and reduced CMT following switching. After switching, BCVA continuously improved in the bevacizumab to ranibizumab group, but stayed stable in the ranibizumab to bevacizumab group. The CMT was reduced at the switching time in both groups, but did not change after the switch. Final visual acuity improved or stabilized in all eyes in the ranibizumab-only group. The BCVA worsened in 20% of eyes in the bevacizumab to ranibizumab group and in 40% of eyes in the ranibizumab to bevacizumab group. Conclusions The ranibizumab-only group and the switching from bevacizumab to ranibizumab group seemed superior to the ranibizumab to bevacizumab group.

Zinc administration modulates radiation-induced oxidative injury in lens of rat

Background: The aim of this study was to evaluate the antioxidant role of zinc (Zn) against radiation-induced cataract in the rat lens after total cranial irradiation with a single 5 Gray (Gy) dose of gamma irradiation. Materials and Methods: Twenty-one Sprague-Dawley rats were used for the experiment. The control group did not receive Zn or irradiation but received 1-ml saline orally plus sham-irradiation. The irradiation (IR) group received 5 Gy gamma irradiation to the total cranium as a single dose plus 0.1 ml physiological saline intraperitoneally. The IR plus Zn group received irradiation to total cranium plus 10 mg/kg/day Zn intraperitoneally. Biochemical parameters measured in rat lenses were carried out using spectrophotometric techniques. Results: Lens total (enzymatic plus non-enzymatic) superoxide scavenger activity (TSSA), glutathione reductase (GRD), and glutathione-S-transferase (GST) activities significantly increased in the IR plus Zn groups when compared with the IR group. However, TSSA, GRD and GST activities were significantly lower in the IR group when compared with the control group. Lens non-enzymatic superoxide scavenger activity (NSSA) in the IR plus Zn group was significantly increased compared to that of the IR group. Lens xanthine oxidase (XO) activity in the IR group significantly increased compared to that of both the control and IR plus Zn groups. Conclusion: Zn has clear antioxidant properties and prevented oxidative stress by scavenging free radicals generated by ionizing radiation in rat lenses.

Retinal fiber layer thickness in children with thalessemia major and iron deficiency anemia.

ABSTRACT Purpose: We aimed to measure peripapillary retinal nerve fiber layer (RNFL) thickness in children with thalassemia major (tha-major), children with iron deficiency anemia (IDA), and children in a healthy control group. Materials and Methods: A total of 47 children with tha-major and 22 children with IDA were selected from two pediatric hematology outpatient clinics as our experimental groups, while 35 healthy children were randomly selected from a primary school to act as a control group. After a complete eye examination was conducted and intraocular pressure measurements were obtained, RNFL measurements were performed using optical coherence tomography, and the information was recorded for statistical analysis. Results: The mean age of the participants was 9.65 ± 4.13 years in the tha-major group, 9.14 ± 2.53 years in the IDA group, and 9.13 ± 3.29 years in the control group, respectively, with no statistically significant difference among the three groups (p > 0.05). Mean peripapillary RNFL thickness was 119.38 ± 35.49 microns in the tha-major group, 184.00 ± 31.14 microns in the IDA group, and 187.73 ± 27.36 microns in the control group. It was significantly thinner in all quadrants in the tha-major group vs. the other two groups (p < 0.01), and in only the inferior quadrant in the IDA group (p < 0.05). Average RNLF thickness correlated positively with mean hemoglobin value (r = 0.488; p < 0.001) and negatively with mean ferritin level (r = −0.544; p < 0.001), but no correlations with mean number of transfusions and mean visual acuity were observed (p > 0.05). Conclusion: The study revealed that peripapillary RNFL is thinner in tha-major in all quadrants and in only the inferior quadrant in IDA. Thinning of the RNLF correlated with hemoglobin value and ferritin level, but not with number of transfusions and visual acuity.

Comparison of Wide Conjunctival Flap and Conjunctival Autografting Techniques in Pterygium Surgery

Pterygium is an abnormal fibrovascular tissue extending on the cornea which is a degenerative and hyperplastic disorder. A stromal overgrowth of fibroblast and blood vessels is accompanied by an inflammatory cell infiltrate and abnormal extracellular matrix accumulation. The surgical excision is the main treatment method of pterygium, but recurrence is the most common postoperative complication. In the present study, we aimed to compare the wide conjunctival flap and the conjunctival autografting techniques in pterygium surgery according to time of operation, safety, and effectiveness. Results showed that the effect of wide conjunctival flap techniques on primary pterygium surgery was found close to the conjunctival autograft techniques. In addition, the flap technique has a shorter surgical time, the surgery does not require extreme experience, feeding of the flap is provided with own vessels since the vascular structure is protected on the upper temporal conjunctival area, reverse placement of the flap is not seen, it needs fewer sutures, so that suture disturbances may reduce, and it is less traumatic than autograft technique during conjunctival transport. Therefore, this technique may be preferred in suitable cases.

The pain experience and cooperation of patients in consecutive cataract surgery.

Purpose The aim of this study was to investigate the pain experience and the cooperation of patients during consecutive cataract surgery. Methods In this prospective, randomized study, 60 consecutive adult patients with bilateral senile cataracts were recruited. All operations were performed with clear corneal phacoemulsification (phaco) technique under topical and intracameral anesthesia without sedation. The first surgery was performed in the eye with high-grade cataract. The other eye was operated within 3 months. Every patient was graded using a visual analogue scale (VAS) from 0 (no pain) to 10 (unbearable pain) after the surgery. The cooperation of the patient was graded from 0 (no event) to 3 (marked eye and head movement and lid squeezing) by the surgeon. The VAS scores and cooperation of patients were the main outcome measurements. Results The mean VAS score was 1.50± 0.81 in the first surgery and 2.15±0.79 in the other eye surgery (p<0.001). The patient cooperation score was 1.50±0.81 in the first surgery and 2.18±0.77 in the other eye surgery (p<0.001). The VAS and patient cooperation scores were positively correlated (r=0.633, p<0.001) in the study group. The VAS and patient cooperation scores were similar based on sex and laterality. Conclusions Patients who previously underwent phaco surgery in one eye experience more pain and have worse cooperation during the other eye phaco surgery.

The radioprotective effect of Nigella sativa on nitrosative stress in lens tissue in radiation-induced cataract in rat.

Abstract Objective: The aim of this study was to investigate the antioxidant and radioprotective effects of Nigella sativa oil (NSO) and thymoquinone (TQ) against ionizing radiation-induced cataracts in lens after total cranium irradiation (IR) of rats with a single dose of 5 gray (Gy). Materials and methods: Seventy-four Sprague-Dawley rats were used for the experiment. The rats were randomly divided into six groups. Group A received total cranium IR plus NSO (1 g kg–1 d–1) orally through an orogastric tube. Group B received total cranium IR plus TQ (50 mgkg–1 d–1) daily by intraperitoneal injection. Group C received 5 Gy of gamma IR as a single dose to total cranium plus 1 ml saline. Group D1 just received 1 ml saline. Group D2 just received dimethyl sulfoxide. Group D3 did not receive anything. Results: At the end of the 10th d, cataract developed in 80% of the rats in IR group only. After IR, cataract rate dropped to 20% and 50% in groups which were treated with NSO and TQ, respectively, and was limited at grades 1 and 2. Nitric oxide synthase activity, nitric oxide and peroxynitrite levels in the radiotherapy group were higher than those of all other groups. Conclusions: The results implicate a major role for NSO and TQ in preventing cataractogenesis in ionizing radiation-induced cataracts in the lenses of rats, wherein NSO were found to be more potent.

Ocular findings in children with thalassemia major in Eastern Mediterranean.

AIM To investigate ophthalmologic findings in children with thalassemia major (TM) and compare the findings with healthy controls. METHODS In a cross-sectional study, 43 children with thalassemia major from pediatric hematology outpatient clinics from two university hospitals and age/sex matched 47 healthy children were included in the study. After a complete ophthalmic examination, tear function tests including the Schirmer test, fluorescein tear break-up time (BUT), ultrasound pachymetry, and axial length measurement were performed. Obtained data was recorded for statistical analysis and the values of right eyes were compared between groups. RESULTS The mean best corrected visual acuity was 1.34±0.75 in TM and 1.08±0.28 in controls. It was found lower than 0.1 logMAR unit in 10 (23.2%) children with TM and 2 (4.2%) in controls, and the difference was statistically significant (P<0.05). The mean central corneal thickness was 540±26.95 in children with TM and 536.98±20.45µm in controls (P>0.05). The mean axial length was 22.53±0.50 in TM and 22.57±0.43mm in the control group. The mean Schirmer test score was 19.94±6.91 in TM and 24.22±3.95mm in the control group (P<0.01). The mean BUT score was 9.62±1.28 in TM and 9.73±0.6s in the control group (P>0.05). CONCLUSION In TM, while corneal thickness, axial length, and BUT are close to controls, the Schirmer scores are less than normal. The study revealed that TM may be affected by the tear function and visual acuity.

Differences of the Anterior Segment Parameters in Children with Down Syndrome

Abstract Purpose: The study was undertaken to investigate whether anterior segment findings are different in children with Down syndrome (DS) to normal children and to focus on its clinical significance. Methods: A cross-sectional case control study was conducted in a total of 38 children with DS and 42 healthy children. This is the first report in the literature stating that. All subjects underwent ophthalmologic examination including slit-lamp biomicroscopy, cycloplegic refraction, intraocular pressure measurement and Scheimpflug imaging measurement. Customized software for Pentacam was used to analyze structural indices of anterior segment parameters. The mean anterior segment values of right eyes were compared between the groups. Results: The mean anterior chamber parameters of patients with DS and controls were measured respectively: Corneal thickness was 502.31 ± 40.5 and 541.8 ± 37.42 mm (p < 0.001), corneal volume was 56.63 ± 4.5 and 61.02 ± 4.3 mm3 (p < 0.001), corneal radius curvature was 7.41 ± 0.29 and 7.67 ± 0.34 mm (p < 0.001), iridocorneal angle was 39.7 ± 6.2 and 39.5 ± 6.4° (p = 0.944), anterior chamber volume was 181.65 ± 27.38 and 185.77 ± 32.53 mm3 (p = 0.528), anterior chamber depth was 3.08 ± 0.24 and 3.02 ± 0.31 mm (p = 447), pupil size was 2.95 ± 0.48 and 3.29 ± 0.45 mm (p < 0.05). Conclusion: The majority of the anterior segment parameters were found to be different in children with Down syndrome. While pupil size, corneal thickness, corneal volume and corneal curvature in DS were less than normal, iridocorneal angle, anterior chamber depth and anterior chamber volume were close to controls. The most important parametric differences in children with DS were seen on the cornea.

Lens capsule-related problems in patients undergoing phacoemulsification surgery

Purpose This study aimed to compare lens capsule-related problems in mature versus non-mature senile cataracts in patients undergoing phacoemulsification surgery. Methods A total of 295 patients with senile cataract were divided into two groups according to lens maturation: 105 patients with mature senile cataract comprised Group 1 (study group) and the remaining 190 with non-mature senile cataract comprised Group 2 (control group). Prior to surgery, ophthalmological examination was undertaken. Patients’ best-corrected visual acuity and intraocular pressure were measured and a slit-lamp examination and funduscopy performed. All examination data were recorded and any capsule-related problems during surgery were also recorded. Patient files were reviewed retrospectively and compared between groups. Fisher’s exact test was used in the statistical analysis. Results In Group 1, the capsule-related problems found were: inability to complete capsulorhexis (seven eyes [6.6%]), posterior capsular perforation (three eyes [2.8%]), and conversion to extracapsular surgery (one eye [0.9%]). A posterior capsular perforation was seen in one eye (1%) in the control group. An intraocular lens was inserted into the sulcus in six eyes (5.7%) and one anterior chamber (0.9%) in Group 1 and into the sulcus in one eye (0.5%) of Group 2. The lens was inserted into the capsular bag in all other patients. Conclusion Delaying surgery in patients with cataracts creates a high risk for capsule-related surgical complications. Although capsule dyes make capsulorhexis easier, capsulorhexis is the most problematic phase of phacoemulsification in mature cataracts.

Ophthalmic findings in acute mercury poisoning in adults: A case series study.

The aim of this study is to report ophthalmic findings of acute mercury poisoning in 48 adults referred to emergency department. Full ophthalmologic examination including the best corrected visual acuity, external eye examination, reaction to light, a slit-lamp examination, funduscopy, intraocular pressure measurements, and visual field (VF) and color vision (CV) tests were performed at the presentation and repeated after 6 months. The parametric values of VF test, the mean deviation (MD), and pattern standard deviation (PSD) were recorded in order to compare patients and the 30 healthy controls. The mean parameter of color confusion index in patients was found to be statistically different than controls (p < 0.01). The MD and PSD in patients were different from controls statistically significant (p < 0.01 and p < 0.01, respectively). There was no correlation between the ocular findings and the urine and blood mercury levels. Methyl mercury, held in the school laboratory for experimental purpose, may be a source of poisoning. In this case series, we showed that acute exposure to mercury had hazardous effect on the visual system, especially CV and VF. We propose that emphasizing the public education on the potential hazards of mercury is crucial for preventive community health.