Araştırmacılar(12)
Birim yayınları
77 →- ArticleAçık Erişim2026Comparison of the Syringe Preparation Time for Ranibizumab Prefilled Syringe versus Bevacizumab, Ranibizumab, and Aflibercept Vials
Uğurlu, Adem; Taşlı, Nurdan Gamze; Karakurt, Yucel; Somuncu, Ahmet Mehmet; Çiçek, İbrahim
Objective: To compare the syringe preparation time for ranibizumab prefilled syringe versus bevacizumab, ranibizumab, and aflibercept vials in routine retinal practice. Methods: The study was conducted retrospectively between July 2019 and February 2021 at the Ophthalmology Department of the Erzincan Binali Yıldırım University Faculty of Medicine, Türkiye. Syringe preparation times for 157 eyes were collected for the study. For each injection, one independent observer recorded the duration of each step required to prepare the syringe, starting with the removal of the ranibizumab prefilled syringe or bevacizumab, ranibizumab, and aflibercept vials from their respective packaging, and ending at the moment the dose was ready for injection. Injections were excluded if disruptions during the drug administration process were due to external factors or if other errors occurred in measuring preparation time. In addition to preparation time, formation of air bubbles during syringe preparation was qualitatively observed. Results: Forty-five eyes were treated with the ranibizumab prefilled syringe, while bevacizumab, ranibizumab, and aflibercept vials were used to treat 40, 36, and 36 eyes, respectively. The mean injection preparation time was 46.5±4.8 s for the syringe and 66.1±7.2 s, 64.2±5.1 s, and 74.7±8.5 s for the bevacizumab, ranibizumab, and aflibercept vials, respectively. Air bubble formation was more frequently observed in the vial groups, particularly in the aflibercept group, than in the prefilled syringe group. Conclusion: The ranibizumab-prefilled syringe required fewer preparation steps and had a lower incidence of bubble formation compared with other vials. Specifically, when preparing the aflibercept vial for injection, dose adjustment took longer than for the bevacizumab and ranibizumab vials, primarily due to air bubbles.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2026Pathophysiology of sildenafil-induced ocular toxicity in rats and treatment
Cicek, Ibrahim; Caliskan, Busra; Yavuzer, Bulent; Altuner, Durdu; Tastan, Tugba Bal; Coban, Taha Abdulkadir; Karatas, Ezgi; Suleyman, Halis
RESULTS: Sildenafil increased oxidant (malondialdehyde) levels and decreased antioxidant levels (total glutathione, superoxide dismutase, catalase) in rat ocular tissues and caused severe oxidative stress. In addition, sildenafil has been shown histopathologically to cause oxidative damage in retinal layers. ATP treatment suppressed oxidative stress and attenuated histopathological damage in the retinal layers. CONCLUSION: ATP protects retinal tissue against sildenafil-induced ocular oxidative damage in rats and may contribute to the development of novel approaches to prevent or treat this damage.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2026Optical Coherence Tomography Angiography–Based Evaluation of Foveal Avascular Zone and Macular Vessel Density in Prediabetic Patients
Utlu, Bahadır; Utlu, Elif Sedanur; Çinici, Emine; Akgöz, Hasan; Bayrakçeken, Kemal; Kozan, Betül Dertsiz
Background: To assess macular layer thickness, macular vessel density, and foveal avascular zone (FAZ) parameters in prediabetic patients compared with healthy normoglycemic controls using optical coherence tomography angiography (OCTA). Methods: Thirty prediabetic patients (group A; fasting plasma glucose 100-125 mg/dL, postprandial plasma glucose 140-199 mg/dL, glycated hemoglobin 5.7%-6.4%) and 30 age-matched normoglycemic subjects (group B) were included. The OCTA imaging was used to evaluate superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities, as well as FAZ area and perimeter. Participants with poor image quality, high refractive error, glaucoma, prior intraocular surgery, chorioretinal atrophy, or other ocular/sys-temic comorbidities were excluded. Results: The SCP and DCP perfusion densities (PDs) were lower in the prediabetic group, with significant reductions in the inferior and temporal quadrants of the DCP and the temporal quadrant of the SCP (P <.05). The FAZ area and perimeter were larger in the prediabetic group but not statistically significant (P >.05). Macular thickness was greater in all quadrants in group A, with significant thickening in the nasal and inferior quadrants (P <.05). Conclusion: Prediabetic patients demonstrated early microvascular and structural changes, including reduced macular PD, increased macular thickness, and FAZ enlargement. These findings suggest subclinical retinal involvement in prediabetes, warranting larger longitudinal studies.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2025Intrastromal Suturing Technique Compared With Interrupted Corneal Suturing Technique, Loose Suture and Knot Exposure: A Comparative Rabbit Study
Ozkan, Kaan; Aydın, Bahri; Ucgul, Ahmet Yucel; Bayrakceken, Kemal; Ozmen, Mehmet Cuneyt; Akata, Rustu Fikret
Purpose: This study aimed to assess the effectiveness of an innovative intrastromal suturing technique in an experimental rabbit model, comparing it to standard interrupted suturing, loose suture, and suturing with knot exposure. Methods: Fourteen adult male New Zealand White rabbits were included in this study. Each rabbit underwent suturing in both eyes, divided into four groups based on suturing techniques. The novel intrastromal suturing technique involved burying the entire suture material within the corneal stroma. Corneal neovascularisation (CoNV) areas were evaluated by image analysis and immune cell densities by in vivo confocal microscopy (IVCM). Results: The intrastromal suturing group demonstrated significantly smaller CoNV areas at both 1 week and 1 month post-suturing compared to other interventional groups, indicating effective mitigation of CoNV development and progression. Moreover, this group exhibited lower immune cell densities in the superficial stromal layer and endothelial layer, suggesting a reduced inflammatory response. Both the loose suture and the knot exposure groups exhibited significant levels of CoNV and heightened immune cell densities. Conclusion: This experimental study demonstrated effectiveness of intrastromal suturing technique in limiting CoNV and immune cell infiltration, common contributors to graft rejection and complications. Furthermore, the study revealed that loose sutures and those with exposed knots are likely to cause more severe CoNV and inflammation, compared to the traditional interrupted suturing technique and intrastromal suturing.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2025Potential effects of adenosine triphosphate and melatonin on oxidative and inflammatory optic nerve damage in rats caused by 5-fluorouracil
Somuncu, Ahmet Mehmet; Somuncu, Busra Parlak; Ozbay, Ahmet Duhan; Cicek, Ibrahim; Suleyman, Bahadir; Mammadov, Renad; Bulut, Seval; Tastan, Tugba Bal; Coban, Taha Abdulkadir; Suleyman, Halis
• AIM: To investigate the effects of adenosine triphosphate (ATP) and melatonin, which have antioxidant and anti-inflammatory activities, on potential 5-fluorouracil (5-FU)-induced optic nerve damage in rats. • METHODS: Twenty-four rats were categorized into four groups of six rats: healthy (HG), 5-FU (FUG), ATP+5-FU (AFU), and melatonin+5-FU (MFU). ATP (4 mg/kg) and melatonin (10 mg/kg) were administered intraperitoneally and orally, respectively. One hour after ATP and melatonin administration, rats in the AFU, MFU, and FUG were intraperitoneally injected with 5-FU (100 mg/kg). ATP and melatonin were administered once daily for 10d. 5-FU was administered at a single dose on days 1, 3, and 5 of the experiment. After 10d, the rats were euthanized and optic nerve tissues were extracted. Optic nerve tissues were biochemically and histopathologically examined. • RESULTS: ATP and melatonin treatments inhibited the increase in malondialdehyde (MDA) and interleukin-6 (IL-6) levels, which were elevated in the FUG. The treatments also prevented the decrease in total glutathione (tGSH) levels and the superoxide dismutase (SOD) and catalase (CAT) activities (P<0.001). This inhibition was higher in the ATP group than in the melatonin group (P<0.001). ATP prevented histopathological damage better than melatonin (P<0.05). • CONCLUSION: ATP and melatonin have the potential to be used in alleviating 5-FU-induced optic nerve damage. In addition, ATP treatment shows better protective effects than melatonin.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2025Anterior and Posterior Ocular Changes in Patients with Active and Inactive Ankylosing Spondylitis
Karakurt, Yücel; Aktaş, Nurdagül; Somuncu, Ahmet Mehmet; Uğurlu, Adem; Çiçek, İbrahim
Background: The 6-item Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) is a method for evaluating disease activity in ankylosing spondylitis (AS). This study included 78 patients with active and inactive AS and aimed to evaluate anterior and posterior segment ocular changes. Material/Methods: Seventy-eight patients and 70 control subjects were enrolled in this study. All participants underwent a complete ophthalmic evaluation. The patients were subdivided into 2 groups according to their BASDAI scores: the active group (BASDAI34) (n: 38) and the inactive group (BASDAI<4) (n: 40). Results: Endothelial cell density (ECD) and hexagonality (HEX) decreased, while coefficient of variation (CV) and average cell size (AVG) increased significantly in AS patients compared with the control cases (P 0.001). However, there was no statistically significant difference between active and inactive groups related to these parameters. Central corneal thickness (CCT) and corneal volume were significantly lower in AS patients (P 0.001, P 0.04), without any statistically significant difference between active and inactive groups. Tear break-up time (TBUT) and Schirmer test results were lower and the findings of corneal fluorescein staining and ocular surface disease index scores (OSDI) were higher in AS patients compared with the control cases, without any significant differences between the active and inactive groups (P 0.001). Choroidal thickness was significantly higher in all 5 points investigated – subfoveal (P 0.018), 1000 Nasal (N) (P 0.003), 2000 N (P 0.001), 1000 Temporal (T) (P 0.007), and 2000 T (P 0.013) in AS patients compared with the control group. Conclusion: AS can cause anterior and posterior changes, even in the absence of uveitis. Therefore, more attention should be paid to ocular surgery and follow-up of ocular diseases in AS patients.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2025Protective Effect of Exogenous Adenosine Triphosphate Against Ocular Toxicity of Linezolid in Rats
Esenulku, Cenap Mahmut; Cicek, Ibrahim; Somuncu, Ahmet Mehmet; Yavuzer, Bulent; Sezgin, Esra Tuba; Tastan, Tugba Bal; Yücel, Nurinisa; Karatas, Ezgi; Suleyman, Halis
Linezolid, a synthetic antimicrobial agent, may induce oxidative damage in ocular tissues, particularly in the optic nerve. Adenosine triphosphate (ATP) is involved in the production of antioxidants that scavenge and neutralize reactive oxygen species. This study aims to evaluate the potential protective effect of exogenous ATP against linezolid-induced ocular damage in rats, in comparison with methylprednisolone. Wistar-type rats were divided into five groups as follows: healthy (HG), ATP-only (ATPG), linezolid-only (LZDG), ATP + linezolid (ATLDG), and methylprednisolone + linezolid groups (MPLDG). Oxidative stress markers, antioxidant biomarkers, and proinflammatory cytokines were analyzed in isolated ocular tissues. Optic nerve tissue was also evaluated histopathologically. Linezolid administration increased the oxidative stress marker MDA and the proinflammatory cytokine TNF-α, while decreasing antioxidant parameters such as tGSH, SOD and CAT in rat ocular tissues, compared to the healthy group. However, it did not significantly alter serum troponin I levels. Histopathological analysis revealed that linezolid induced oxidative damage and inflammation in optic nerve tissue, with marked glial alterations. ATP administration reduced linezolid-induced oxidative stress in ocular tissue, as indicated by decreased MDA levels. It also enhanced antioxidant defenses by increasing tGSH, SOD, and CAT levels. In addition, ATP lowered proinflammatory cytokine levels, thereby alleviating inflammation. These effects collectively contributed to the restoration of biochemical parameters toward normal levels. In addition, ATP mitigated linezolid-induced optic nerve damage and glial alterations. The critical role of ATP in reducing oxidative stress, restoring antioxidant balance, and suppressing inflammation may represent a promising therapeutic approach for linezolid-induced ocular toxicity.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2024Lacidipine, thiamine pyrophosphate and their combination on the ocular ischemic syndrome induced by bilateral common carotid artery ligation
Cicek, Ibrahim; Somuncu, Ahmet Mehmet; Altuner, Durdu; Suleyman, Bahadir; Mammadov, Renad; Bulut, Seval; Coban, Taha Abdulkadir; Tastan, Tugba Bal; Suleyman, Halis
AIM: To investigate the effect of lacidipine, thiamine pyrophosphate (TPP) and the combination of lacidipine and TPP against oxidative and inflammatory eye damage induced by bilateral common carotid artery ligation in rats.. METHODS: Male albino Wistar rats were categorized as those who underwent sham surgery (SG), right and left common carotid cross-clamping and unclamping procedure (CCU), lacidipine+CCU (LCCU), TPP+CCU (TCCU), and combination of lacidipine and TPP (LTC)+CCU (LTCCU). One hour before anesthesia, the LCCU (n=6) received lacidipine (4 mg/kg, orally) and the TCCU (n=6) received TPP (20 mg/kg, intraperitoneally). The SG (n=6) and CCU (n=6) received the same volume of distilled water from the same route. After anesthesia (60 mg/kg ketamine, intraperitoneally), the necks of the rats were opened in the midline. Ischemia was created for 10min by placing clips on the right and left common carotid arteries. Rats in the SG only underwent subcutaneous incision. After 10min, the clips were removed and reperfusion was achieved for six days. Then, the animals were euthanized (120 mg/kg ketamine, intraperitoneally) and the levels of oxidant, antioxidant and proinflammatory cytokines in the eye tissues were determined. The retinal tissue of the eye was also examined histopathologically.. RESULTS: Lacidipine, TPP, and LTC significantly prevent the increase in malondialdehyde, tumor necrosis factor-alpha, interleukin-1β (IL-1β), and IL-6 levels, decrease in total glutathione levels, superoxide dismutase and catalase activities and histopathological retinal damage in eye tissue induced by bilateral common carotid artery ligation in rats. The impact of these drugs on protection is determined to be LTC>lacidipine>TPP.. CONCLUSION: As a result of the study, it is concluded that LTC may be more effective than lacidipine and TPP alone in treating ocular ischemic syndrome.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2023Short-term effect of latanoprostene bunod monotherapy on reducing intraocular pressure and altering macular microvasculature Latanoprostene bunod monotherapy on glaucoma
Bayrakçeken, Kemal; Akgöz, Hasan
Aim: In this study, we aimed to evaluate the effect of topical latanoprostene bunod (LBN) 0.024% on early intraocular pressure (IOP) and macular microvasculature. Material and Methods: This retrospective study included 46 eyes of 46 treatmentnaive participants with primary open-angle glaucoma disease (POAG) who were initiated on topical LBN 0.024%. IOP values of the patients were compared before and the first month after treatment. Macular and ganglion cell complex thicknesses were evaluated using optical coherence tomography (OCT), and macular vessel density parameters were evaluated using OCT angiography (OCTA). Pre-and post-treatment findings were compared with the paired-sample t-test. Results: At the time of the first presentation, the mean IOP value of the patients was 26.20 +/- 2.84 mmHg. After administration of LBN 0.024%, the mean follow-up IOP value decreased to 14.93 +/- 2.25 mmHg in the first month (p=0.00). When OCTA images taken before and the first month after treatment were compared, it was determined that the early treatment diabetic retinopathy study (ETDRS) value for the outer nasal section significantly increased (p=0.042). There was no significant difference in the remaining parameters showing macular vessel density. Discussion: LBN 0.024% is a topical ocular hypotensive agent effective in lowering IOP in the early period in patients with POAG.
RDL Kalıcı Kaydıİncele - ArticleYayıncıda açık erişim2023Evaluation of the effect of trypan blue on the corneal endothelium in cataract surgery
Bayrakceken, Kemal; Utlu, Bahadir
Aim: In this study, we aimed to evaluate the safety of 0.06% trypan blue applied to visualize the anterior capsule in cataract surgery. Material and Methods: This single-center, prospective, randomized controlled study included 40 eyes of 20 patients. While performing cataract surgery on the right eyes of the patients, trypan blue was not used, and these eyes were evaluated as the control group. For the left eyes, trypan blue was used during surgery. The endothelial cell density (ECD) values of the two groups were measured, recorded, and analyzed at baseline and one week and one month after surgery, and their central corneal thicknesses were evaluated at baseline and one month after surgery. Results: There was no statistically significant difference between the trypan blue and control groups in terms of the first-week (p=0.852) and first-month (p=0.881) ECD values and first-month pachymetry values (p=0.218). However, the ECD and pachymetry values significantly differed in both groups at one week and one month after surgery compared to the baseline (p<0.001). Discussion: Our results showed that trypan blue injection into the anterior chamber to achieve comfortable and safe capsulorhexis in cataract surgery does not cause any adverse effects on the corneal endothelium.
RDL Kalıcı Kaydıİncele
Tam Kayıt
| Alan | Değer | Dil |
|---|---|---|
| dc.date.accessioned | 2026-10-20T15:26:02.590567045Z | |
| dc.date.available | 2026-10-20T15:26:02.590567045Z | |
| dc.identifier.uri | https://rdlopen.rawdatalibrary.net/r/ebyu/22860 | |
| dc.rights | info:eu-repo/semantics/openAccess | |
| dc.title | Göz Hastalıkları Anabilim Dalı | tr |
| dc.title | Department of Ophthalmology | en |
| dspace.entity.type | OrgUnit | |
| organization.identifier.code | tip-goz | |
| organization.unitType | department | |
| rdl.unit.alias | ophthalm |