Umay Güvenç

Dr. Umay Güvenç

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 March 2025 in Medicina
Verified
Journal Article
Open access
PDF file
GSGülizar Soyugelen
Gülizar Soyugelen
UGUmay Güvenç
Umay Güvenç
ABAyşe Burcu
Ayşe Burcu
Background and Objectives: The search for less invasive and more effective methods in the surgical treatment of glaucoma continues. For advanced glaucoma, all surgical options carry a high risk of complications and vision loss. The aim of this study was to evaluate the outcomes of gonioscopy-assisted transluminal trabeculotomy (GATT) surgery in advanced glaucoma. Materials and Methods: In this retrospective study, advanced open-angle glaucoma (OAG) patients were followed up on the 1st day, 1st week, and 1st month, then monthly for 6 months and then every 3 months after GATT surgery. Outcomes at 6 and 24 months were analyzed to evaluate early and long-term surgical success. Surgical success was defined as a ≥20% intraocular pressure (IOP) reduction from baseline, final IOP ≤21 mmHg, and no need for additional glaucoma surgery. Pre- and postoperative measurements included IOP, retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT), peripapillary vessel density (VD) via optical coherence tomography angiography, and visual field (VF) tests. Results: Among 44 advanced glaucoma patients (61.4% pseudoexfoliative glaucoma), surgical success was 81.8% at 6 months and 76.5% at 24 months. Mean IOP decreased from 26.9 ± 10.4 mmHg preoperatively to 13.8 ± 8.3 mmHg at 3 months (40.36% reduction, p < 0.001) and 13.9 ± 4.0 mmHg at final follow-up (42.12% reduction, p < 0.001). Disease progression was absent in 66% of patients. BCVA initially declined (0.61 ± 0.36 to 0.41 ± 0.33 logMAR at 3 months, p = 0.011) but returned to baseline (0.59 ± 0.35 logMAR at final follow-up, p = 1.00). Glaucoma medications decreased by 66.2%, and peripapillary VD remained stable (p > 0.05). The most common complication was mild hyphema (34.1%), which resolved without intervention; only one patient (2.3%) experienced vision-threatening complications (wipe-out phenomenon in degenerative myopia). Conclusions: GATT is a safe and effective alternative to trabeculectomy for advanced glaucoma, achieving significant IOP reduction with stable VD and low rates of serious complications. This study provides novel insights by offering long-term (24-month) follow-up data, evaluating peripapillary VD stability, and specifically assessing GATT outcomes in an advanced glaucoma cohort. However, caution is advised in patients with additional ocular pathologies.

18 March 2024 in International Journal of Ophthalmology
Verified
Journal Article
Open access
PDF file
UGUmay Güvenç
Umay Güvenç
GÜGüner Üney
Güner Üney
SUSelma Uzman
Selma Uzman
AIM: To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma (NTG) who do not exhibit typical glaucoma manifestations. METHODS: A retrospective analysis was conducted on 90 atypical NTG patients who underwent cranial magnetic resonance imaging (MRI) due to atypical symptoms. The demographic characteristics, clinical parameters, and radiological findings were recorded. RESULTS: Among the patients, 66.7% had abnormal radiology results, with the most common findings being gliosis (34.4%), sequelae of cerebrovascular events and vascular malformations (14.4%), and benign intracranial mass lesions (11%). Non-glaucomatous visual field defects were more frequently observed in patients with abnormal neuroimaging results. However, there were no significant differences in intraocular pressure, optic disc parameters, retinal nerve fiber layer thickness, and visual field indices between patients with normal and abnormal radiological results. The mean age of the patients was 58.74y. Interestingly, there was a significant age difference, with the abnormal radiology group having a higher median age (P=0.021). CONCLUSION: The study highlights the importance of cranial imaging in older NTG patients to detect underlying pathologies and prevent misdiagnosis. It suggests that neuroimaging may be warranted in NTG patients with atypical visual field defects incompatible with glaucoma. However, routine neuroimaging in all NTG patients without classic neurological signs may not be necessary.

16 June 2025 in Korean Journal of Ophthalmology
Verified
Journal Article
Open access
PDF file
UGUmay Güvenç
Umay Güvenç
ZAZüleyha Yalnız Akkaya
Züleyha Yalnız Akkaya
ABAyşe Burcu
Ayşe Burcu
Pseudophakic corneal edema (PCE) remains a significant postoperative challenge despite advancements in cataract surgery, often delaying visual recovery and affecting refractive outcomes. This study investigates the relationship between keratometric and pachymetric changes during PCE resolution, evaluates factors influencing this process, and examines the efficacy of Coenzyme Q10 (CoQ10) as an adjunct therapy. A retrospective study was conducted on 88 patients aged 50 and above who developed PCE after uneventful phacoemulsification. Corneal assessments were performed using Pentacam HR, focusing on keratometric and pachymetric changes. Patients were monitored weekly until PCE resolution, defined as a return of central corneal thickness within ±30 microns of preoperative values. Patients received standard postoperative treatment, with a subset also receiving CoQ10 as an adjunct therapy. Postoperative visual acuity(VA) improved significantly (p < 0.001). Despite pachymetric normalization, persistent keratometric changes were observed, particularly a steepening of posterior curvature (p<0.001) and increased anterior asphericity (p = 0.047). CoQ10-treated patients exhibited faster edema resolution (p = 0.019), greater reduction in corneal thickness (p = 0.003), and improved transparency. Higher cumulative dissipated energy (CDE) correlated with increased edema severity (r = 0.419, p<0.001) and higher CDE was linked to slower recovery times. Diabetic patients had a prolonged recovery period compared to non-diabetics (p = 0.018), though pachymetric recovery rates were similar.. The Pachymetric Progression Index (PPI) was unreliable in edematous corneas. While VA and pachymetry improved in all patients, persistent topographic changes suggest incomplete structural normalization. Preliminary findings indicate that adjunctive CoQ10 use may support more efficient corneal edema resolution, as evidenced by faster recovery and favorable structural changes. Further prospective studies are warranted to confirm these observations.

18 September 2023 in International Journal of Ophthalmology
Verified
Journal Article
Open access
PDF file
UGUmay Güvenç
Umay Güvenç
NUNurten Unlu
Nurten Unlu
MAMehmet Akif Acar
Mehmet Akif Acar
DHDicle Hazırolan
Dicle Hazırolan
OCOzlem Candan
Ozlem Candan
AIM: To evaluate the retinochoroidal microvascular circulation and anatomical structure of diabetic and non-diabetic patients with epiretinal membrane (ERM) with the help of optical coherence tomography angiography (OCT-A) and compare them with healthy control subjects. METHODS: In this prospective, cross-sectional study, a total of 165 eyes were evaluated, including 50 eyes of patients with diabetic ERM, 54 eyes of idiopathic ERM (iERM) patients, and 61 eyes of healthy controls. Macula and disc angiography was performed by OCT-A. Macular vessel density (VD) ratio was evaluated by dividing the VD of the foveal region by the VD of the parafoveal region. Statistical calculations were evaluated at the 95% confidence interval. RESULTS: Macula superficial VD values of ERM cases were lower than that in the control group, while foveal VD was higher in ERM cases. Macula deep VD values of ERM cases were lower in all quadrants, except the fovea. The width of the foveal avascular zone (FAZ) area was significantly lower in the ERM groups, and the FAZ width was lowest in iERM group. Macula superficial VD ratio was significantly higher in the ERM groups, but there was no significant difference between ERM groups. Macula deep VD ratio was significantly higher in the iERM group than in the control group. CONCLUSION: Diabetic and idiopathic ERMs differ in their mechanism of formation and clinical presentation, as well as their effect on retinal vascular structures. If the relationship of increase of retinal thickness with vascular integrity can be demonstrated with OCT-A, then, OCT-A can be used as a guide for ERM prognosis.

30 June 2023 in International Ophthalmology
Verified
Journal Article
Closed access
PDF file
UGUmay Güvenç
Umay Güvenç
NÜNurten Ünlü
Nurten Ünlü
HYHüsniye Neşe Yaralı
Hüsniye Neşe Yaralı
NÖNamık Yaşar Özbek
Namık Yaşar Özbek

13 August 2025 in International Ophthalmology
Verified
Journal Article
Closed access
UGUmay Güvenç
Umay Güvenç
GÜGüner Üney
Güner Üney
NÜNurten Ünlü
Nurten Ünlü
ÖCÖzlem Candan
Özlem Candan
GOGözde Orman
Gözde Orman