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Öğe Automatic detection of keratoconus on Pentacam images using feature selection based on deep learning(Wiley, 2022) Firat, Murat; Cankaya, Cem; Cinar, Ahmet; Tuncer, TanerToday, corneal refraction, height, and thickness data, which are required in the diagnosis of keratoconus, can be obtained with corneal tomography devices. Pentacam four map display presenting this data is one of the most basic options in the diagnosis of keratoconus. In this article, an artificial intelligence-based method using Pentacam images is proposed to distinguish keratoconus from healthy eyes. Axial/sagittal curvature, back elevation, front elevation, and corneal thickness map images of a total of 341 keratoconus and 341 healthy corneas obtained from Inonu University ophthalmology clinic as the data set were given as input to AlexNet, one of the deep learning models, and the feature vectors of each image were obtained and combined. The most effective features in the determination of keratoconus were determined by applying ReliefF, minimum-redundancy-maximum-relevance (mRMR) and Laplacian algorithms, which are widely used in feature extraction algorithms, to the obtained feature vector. These features are classified using the support vector machine (SVM) classifier, which has high performance in binary classification. The accuracy, specificity, and sensitivity of keratoconus detection with the proposed method were found to be 98.53%, 99.01%, and 98.06%, respectively. The developed model can support the clinician to evaluate the features of the cornea and to detect keratoconus, which is difficult through subjective assessments, especially in the subclinical and early stages of the disease.Öğe Bilateral Congenital Cystic Eye Posterior to the Lower Eyelid: Case Report(Ortadogu Ad Pres & Publ Co, 2012) Doganay, Selim; Alkan, Alpay; Cankaya, Cem; Firat, PenbegulOne day after delivery, an infant boy was referred to our clinic with the complaint of bilateral inferior eyelid bluish discoloration and absence of globe in orbital space. External ocular examination showed no globe in orbital space but a mild bulging of the right and left lower eyelid with an area of bluish discoloration. There were no other ocular or non-ocular abnormalities. Systemic evaluation was normal. Magnetic resonance imaging (MRI) confirmed presence of bilateral cystic eye and absence of ocular structures in orbital space. MRI at age of 14 months showed enlargement of the left cystic eye. A clear fluid (5 cc) was aspirated from the cyst to restore the globe size within the lower eyelid. Biochemical analysis of cystic fluid revealed no abnormalities.Öğe Coexistence of pituitary incidentaloma and primary hyperparathyroidism mimicking multiple endocrine neoplasia Type 1: A case report(2021) Gorgel, Ahmet; Tecellioglu, Mehmet; Cankaya, CemThe widespread use of imaging procedures has led to an increased discovery of incidental masses in the pituitary gland. Although the majority of pituitary incidentalomas are non-functioning benign adenomas but their increased prevalence poses a diagnostic and therapeutic challenge. These masses may cause various hormonal disturbances as well as they might also be a component of multiple endocrine neoplasia syndromes type 1 (MEN-1) or type 4 (MEN-4). In both syndromes, primary hyperparathyroidism frequently accompanies with pituitary adenomas. Herein we present a 56-year-old man with pituitary incidentaloma who is also detected primary hyperparathyroidism. Contrary to our expectations, any gene defects could be found related with neither MEN-1 nor MEN-4 in the genetic examinatioÖğe Corneal Endothelial Changes in Behcet's Patients with Inactive Ocular Involvement(Taylor & Francis Inc, 2018) Cankaya, Cem; Cumurcu, Tongabay; Gunduz, Abuzer; Firat, IlknurPurpose: The purpose of this article is to evaluate alterations in the corneal endothelial layer in Behcet's disease (BD) with inactive ocular involvement using specular microscopy.Materials and Methods: Thirty-three eyes of 33 BD patients who had at least one anterior segment involvement and no active inflammation in the last 3months were included in the study (group 1). Twenty-seven of the 33 BD patients had an anterior uveitis attack and six of them had a panuveitis (both anterior and posterior involvement) attack. Thirty-three eyes of 33 age- and sex-matched healthy subjects were enrolled in the control group (group 2). Corneal endothelial cell density (CD), coefficient of variation (CV), hexagonal cell ratio (HEX), and central corneal thickness (CCT) were measured using specular microscopy (Konan Medical, Nishinomiya, Japan), and the results were compared between groups.Results: The mean CD was 2739164.18 cells/mm(2) in group 1 and 2922 +/- 107.60 cells/mm(2) in group 2 (p=0.001). The mean CV was 32.9 +/- 4.76 in group 1 and 28.5 +/- 3.06 in group 2 (p=0.001). The mean HEX was 44.7 +/- 6.51 in group 1 and 49.7 +/- 6.10 in group 2 (p=0.019). The mean CCT was 545.75 +/- 40.89 in group 1 and 545.66 +/- 30.09 in group 2 (p>0.05).Conclusions: Ocular attacks in our BD patients may have caused permanent changes in the corneal endothelial layer. However, these changes did not lead to corneal decompensation, but further studies are necessary to confirm these results.Öğe Corneal endothelial changes in patients with vitamin D deficiency(Wolters Kluwer Medknow Publications, 2018) Cankaya, Cem; Cumurcu, Tongabay; Gunduz, AbuzerPurpose: The purpose of this study is to evaluate the effect of vitamin D deficiency on corneal endothelial layer using specular microscopy. Methods: Fifty-eight eyes of 58 patients whose vitamin 13 level was below 15 ng/ml and who had no ocular pathology were included in the study (Group 1). Forty eyes of 40 age-and sex-matched subjects were enrolled as control group (Group 2). Corneal endothelial cell density (CD), coefficient of variation (CV), hexagonal cell ratio (HEX), and central corneal thickness (CCT) were measured using specular microscopy (Konan Medical Inc., Nishinomiya, Japan). The obtained data were compared between the groups. Results: There was no significant difference between the groups in terms of age and gender (P = 0.344, P = 0.399, respectively). The mean CD value was 2772.79 +/- 202.21 cells/mm(2) in Group 1 and 2954.97 +/- 116.89 cells/mm(2) in Group 2 (P = 0.001). The mean CV value was 30.31 +/- 3.65 in Group 1 and 28.20 +/- 2.71 in Group 2 (P = 0.003). The mean HEX value was 46.56 +/- 6.32 in Group 1 and 51.07 +/- 5.28 in Group 2 (P = 0.001). The mean CCT value was 555.87 +/- 36.90 mu in group 1 and 549.0 +/- 37.39 mu in Group 2 (P = 0.96). Conclusion: Vitamin D deficiency may affect the corneal endothelial layer. Patients with vitamin D deficiency should be evaluated for endothelial parameters in particular before an intraocular surgery. Further studies are needed to confirm our results.Öğe Corneal tattooing for esthetic purposes in patients with corneal opacities(Wolters Kluwer Medknow Publications, 2020) Doganay, Derya; Doganay, Selim; Cankaya, CemPurpose: This study evaluated corneal tattooing for esthetic purposes in patients with corneal opacification. Methods: Eight eyes of eight patients were included in the study (four males and four females). Corneal tattooing was achieved by stromal puncture in five patients, femtosecond laser-assisted corneal tattooing in two patients, and femtosecond laser-assisted corneal tattooing and stromal needling (combined procedure) in one patient. In six of the patients, the entire cornea was stained black; in one patient, the center of the cornea (3 mm) was stained black and the periphery was stained dark brown; and in the last patient, the corneal periphery was stained dark brown. Patient satisfaction was evaluated on the first day after surgery and at the last visit as follows: Very satisfied (4), satisfied (3), moderately satisfied (3), and not satisfied (1). Results: The patients ranged in age from 11-80 years. The mean satisfaction score of the patients was 4 and 3.5 on the first postoperative day and at the last visit, respectively. No complication occurred during or after surgery. Conclusion: Corneal tattooing for esthetic purposes was successful in both blind eyes and seeing eyes.Öğe Correlation between corneal endothelial layer features and age-related macular degeneration severity(Springer, 2024) Ozturk, Emrah; Cankaya, Cem; Yildizli, YakupPurposeThis study aimed to investigate the relationship between corneal endothelial layer features and the severity of age-related macular degeneration (AMD).MethodsThe study included 119 patients, with 47 females and 72 males. Patients were categorized into four groups based on the AREDS grading system: no AMD (group 1), mild AMD (group 2), moderate AMD (group 3), and advanced AMD (group 4). Only the right eye of patients with both eyes suitable for the study was included. Corneal endothelial cell density (CD), coefficient of variation (CoV), hexagonal cell ratio (HEX), and central corneal thickness (CCT) were measured using specular microscopy (Konan Medical Inc., Nishinomiya, Japan).ResultsGroup 1 had 40 patients, group 2 had 27 patients, and groups 3 and 4 had 26 patients each. Significant differences were observed between the mean endothelial CD, CoV, and HEX values among the groups, while no significant difference was found in CCT values (p = 0.049, p = 0.002, p = 0.004, and p = 0.883, respectively). A mild negative correlation was observed between AMD severity and CD and HEX values, while a mild positive correlation was found between AMD severity and CoV.ConclusionIncreasing severity of AMD may negatively impact corneal endothelial layer values.Öğe Does Inferior Oblique Muscle Overaction Affect Ocular Vestibular Evoked Myogenic Potentials?(Pera Yayincilik Hizmetleri, 2023) Demir, Ismail; Yalcin, Muhammed Zeki; Cengiz, Deniz Ugur; Aydin, Sukru; Cankaya, Cem; Tekin, Ahmet MahmutObjectives: Inferior oblique muscle overaction (IOOA) is a common ocular motility disorder. Ocular Vestibular Evoked Myogenic Potentials (oVEMP) are tests that evaluate the reflex pathway between the utricular macula and the inferior oblique muscle to detect vestibular diseases. Our study is of great importance as it is the first study in the literature to evaluate the effect of inferior oblique muscle overaction on oVEMP parameters. Methods: Thirty-five patients with unilateral inferior oblique muscle overaction (IOOA group) and 18 healthy volunteers without any neurological or vestibulocochlear disease were included in this study. All patients and healthy volunteers were evaluated with oVEMP. Results: No statistically significant difference was found between the n1 latency, p1 latency, n1-p1 latency measurement values of the participants included in the study (p>0.05). A statistically significant difference was found between the n1-p1 amplitude measurement values of the participants in patient groups (non-squint eyes, squint eyes) and control groups (p-value was 0.038). Conclusion: In IOOA patients, vestibulo-ocular reflex pathway may be affected, vestibular symptoms may develop thus o-VEMP responses may be affected. A careful anamnesis should be taken in IOOA patients, and it should be kept in mind that n1-p1 amplitudes and asymmetries may be significantly higher when o-VEMP is performedÖğe The effect of apricots on the experimental cataract model formed by sodium selenite(Pergamon-Elsevier Science Ltd, 2013) Doganay, Selim; Duz, Cem; Firat, Penpe Gul; Cankaya, Cem; Kutukde, Derya; Cigremis, YilmazThis study was designed in order to investigate whether sun dried apricots have a preventive effect on the experimental cataract model formed by sodium selenite in rats. Fifty-nine Spraque-Dawley rat pups were divided into three groups. Group I (control group) consisted of twenty rat pups, born from the rats nourished ad libitum. Group 2 consisted of 18 newborn rats, born from the rats nourished ad libitum with 10% sun dried natural apricots. Group 3 consisted of 21 newborn rats, born from the rats nourished ad libitum. Subcutaneous (30 nmol/gr) sodium selenite injection was applied to all the newborn rats except the control group (Group 1) on postpartum day 10. Cataract development was graded by slit-lamp examination and photography. Encapsulated lenses were analyzed for reduced glutathione (GSH) and malondialdehyde (MDA), a marker of lipid per oxidation. Lenses were also analyzed for total nitrite (TN). The presence of oxidative stress in selenite cataract development and its prevention by sun dried apricots. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Effect of Fasting on Contrast Sensitivity in Healthy Males(Wolters Kluwer Medknow Publications, 2019) Gok, Zarife Ekici; Gunduz, Abuzer; Cankaya, CemPurpose: To evaluate the effect of fasting on contrast sensitivity (CS) in healthy male individuals during the month of Ramadan. Methods: This study included 45 healthy male individuals, aged between 20 and 40 years, working in the same environment. Functional acuity contrast testing (F.A.C.T) was performed using the Optec 6500 vision testing system. Measurements taken during a state of satiety one week before Ramadan were compared with those taken a minimum of 12 hours after the start of fasting in the first and fourth weeks of Ramadan. Results: Contrast sensitivity (CS) was increased at the spatial frequency of three cycles per degree (cpd) at the end of the first week of Ramadan in comparison to the CS measured before Ramadan (P = 0.03). The mean CS values were increased at the spatial frequencies of 3 and 12 cpd at the end of the last week of Ramadan in comparison to the mean values measured before Ramadan (P = 0.01 for both). Conclusion: Although we found statistically significant increases in CS at certain frequencies, we can conclude that Ramadan fasting has no negative effects on CS.Öğe Effect of inferior oblique anterior transposition in correcting vertical hyperdeviation in primary position(Canadian Ophthal Soc, 2019) Gunduz, Abuzer; Firat, Murat; Ozsoy, Ercan; Cankaya, CemObjective: To evaluate the effect of inferior oblique anterior transposition (IOAT) on improvement of vertical hyperdeviation in primary position. Methods: This study was a retrospective review and included 35 eyes of 33 patients (18 males and 15 females). Patients with dissociated vertical deviation were not included in the study. Preoperative and postoperative average follow-up was 11.46 +/- 11.73 and 11.43 +/- 9.73 months, respectively. The eyes were divided into 5 groups according to the amount of transposition. Inferior oblique muscle was transpositioned 2 mm posterior to the inferior rectus insertion in group 1; 1 mm posterior to the inferior rectus insertion in group 2; parallel to the inferior rectus insertion in group 3; 1 mm anterior to the inferior rectus insertion in group 4; and 2 mm anterior to the inferior rectus insertion in group 5. Results: The mean preoperative and postoperative vertical hyperdeviation were 16.52 +/- 5.54 and 0.97 +/- 2.34 prism diopters (PD), respectively. The mean preoperative vertical hyperdeviation in group 1, group 2, group 3, group 4, and group 5 was 11.0 +/- 4.24, 12.88 +/- 4.26, 16.63 +/- 3.50, 19.83 +/- 2.71, and 25.5 +/- 3.00 PD, respectively. Postoperatively, improvement in vertical hyperdeviation in group 1, group 2, group 3, group 4, and group 5 was 11.0 +/- 4.24, 11.63 +/- 3.20, 15.46 +/- 3.19, 18.17 +/- 2.23, and 25.5 +/- 3.00 PD, respectively. The vertical hyperdeviation had improved 100% in group 1; 90.2% in group 2; 92.9% in group 3; 91.59% in group 4; and 100% in group 5. Conclusion: IOAT surgery planned according to hyperdeviation amount has effective and predictable results in correcting vertical hyperdeviation in primary position.Öğe Effect of Vitamin D Deficiency on Contrast Sensitivity Function(Taylor & Francis Inc, 2020) Ozturk, Emrah; Cankaya, CemPurpose The purpose of this study is to investigate the effects of vitamin D (vit D) deficiency on contrast sensitivity (CS) function and retinal layers. Materials and methods Group 1 consisted of 42 patients aged between 18 and 50 years with vit D deficiency and Group 2 consisted of sex- and age-matched 34 healthy subjects with normal vit D levels. Functional acuity contrast testing (FACT) was performed using the Optec 6500 vision testing system. The average retinal nerve fiber layer (RNFL) thickness and macular thickness (MT) obtained from nine macular areas in the Early Treatment Diabetic Retinopathy Study were evaluated using SD-OCT (RS-3000; Nidek Inc., Fremont, CA, USA) following a detailed ophthalmologic examination. Measurements were performed on both eyes. Results A lower CS was found in Group 1 compared to Group 2 in all spatial frequencies. A statistically significant difference was observed between the groups in 6, 12 and 18 cpd spatial frequencies, respectively. (p = .004, p = .001, p = .042, respectively). There was no statistically significant difference between groups in terms of RNFL thicknesses (p = .200). There was an increase in MT in Group 1. However, this increase was statistically significant in the inferior inner area in the right eye, and in the inferior inner, temporal inner and outer macular areas in the left eye (p = .018, p = .003, p = .033, p = .040, respectively). Conclusion It was observed that vit D deficiency had negative effects on CS function and also caused thickness difference in certain segments of retinal layers.Öğe Estimation of angle kappa and pupil barycentre configuration in myopic tilted disc syndrome(Wiley, 2020) Cankaya, Cem; Ozsoy, Ercan; Demirel, Ersin Ersan; Polat, Nihat; Gunduz, AbuzerBackground To evaluate the angle kappa and pupil barycentre configuration in patients with myopic tilted disc syndrome (TDS). Methods Thirty-five eyes of 35 patients with TDS were included in the study. Thirty-five eyes of 35 age- and sex-matched healthy subjects were enrolled in the control group. All measurements were performed with the Lenstar LS 900. Angle kappa was calculated according to Pythagorean theorem using the x and y co-ordinates of the pupil centre. Pupil dx and pupil dy values (pupil dx: x co-ordinate of pupil centre relative to corneal apex, pupil dy: y co-ordinate of pupil centre relative to corneal apex) were used to evaluate the pupil barycentre configuration. Central corneal thickness, white to white (cornea diameter), pupil diameter, anterior chamber depth, lens thickness, and axial length were also measured. Results The calculated mean angle kappa distance was 0.27 +/- 0.15 mm in the TDS group and 0.29 +/- 0.23 mm in the control group (p = 0.42). The mean pupil dx was -0.01 +/- 0.24 mm in the TDS group and -0.17 +/- 0.14 mm in the control group (p = 0.006). The mean pupil dy was -0.02 +/- 0.13 mm in the TDS group and -0.05 +/- 0.22 mm in the control group (p = 0.65). Conclusions The pupil barycentre in TDS cases was statistically significantly closer to the corneal vertex on the horizontal plane compared to the control group. However, there was no statistically significant differences in terms of angle kappa and pupil dy values between the groups. According to our results, refractive surgery can be performed safely with respect to complications related to decentration of ablation zone and decentration of multifocal intraocular lenses in these groups of patients.Öğe Evaluation of Antimicrobial Activities of Topical Anesthetics(Ortadogu Ad Pres & Publ Co, 2011) Orman, Gozde; Cankaya, Cem; Doganay, Selim; Gunal, Selami; Otlu, BarisObjective: To investigate the antimicrobial activities of the drugs used as topical anesthetics. Material and Methods: Test drugs (oxybuprocaine 0.4%, proparacaine hydrochloride 0.5%, lidocaine 10%) were tested for Staphylococcus aureus (S. aureus) ATCC 29213, Streptococcus pneumoniae (S. pneumoniae)ATCC 27336, Pseudomonas aeruginosa (P. aeruginosa) ATCC 27853, standard strains of Escherichia coli (E. coli) ATCC 25922 and Candida albicans (C. albicans) using modified microplate alamar blue method (MABA) in different concentrations according to Clinical and Laboratory Standards Institute (CLSI) criteria. Results: S. Pneumoniae proliferated in none of the dilutions of three topical anesthetics. S. aureus proliferated in all dilutions of oxybuprocaine and lidocaine and in no dilutions of proparacaine hydrochloride. P. Aeruginosa proliferated in 0.2% dilution of oxybuprocaine and 2.5% and 5% dilutions of lidocaine and in all dilutions of proparacaine hydrochloride. C. albicans proliferated in 0.05% and 0.025 % dilutions of oxybuprocaine, 1.25% and 0.625% dilutions of lidocaine, 0.125%, 0.0625% and 0.0312% dilutions of proparacaine hydrochloride. E. Coll proliferated in all dilutions of oxybuprocaine, 0.625% dilutions of lidocaine and 0.125%, 0.0625% and 0.0312% dilutions of proparacaine hydrochloride. Conclusio: Topical anesthetics that are used before sample collection in superficial ocular infections can cause false results in cultures by inhibating proliferations of microorganisms. Thus, it is important to know the effects of topical anesthetics and dilutions on bacterial proliferation.Öğe Evaluation of corneal biomechanical properties after uneventful standard coaxial phacoemulsification surgery(2018) Cankaya, Cem; Ulas, Fatih; Doganay, Derya; Firat, Penpegul; Doganay, SelimAim: This study was designed to investigate the alteration of intraocular pressure measurements and biomechanical properties of the cornea in patients who underwent uneventful standard coaxial phacoemulsification cataract surgery through 2.75 mm corneal main incision with intraocular lens implantation. Material and Methods: 15 eyes of 15 patients admitted to our clinic because of the cataract problems in the study. Corneal hysteresis (CH), corneal resistance factor (CRF) measurements, Goldmann correlated (IOPg), and corneal compensated intraocular pressure (IOPcc) values were recorded by ocular response analyzer (ORA) before and 1 day, 1 week and 1 month after surgery. Results: The mean age of the patients was 64.3 ± 8.06 years. Preoperative mean CH, CRF, IOPg and IOPcc values were 8.23±2.10, 9.33±2.27, 18.54±3.42 and 19.66±3.22, respectively. The mean CH, CRF, IOPg and IOPcc values were 5.50±2.07, 8.69±2.04, 22.29±3.37 and 23.83±3.32, respectively on the first day after the surgery. The mean CH, CRF, IOPg and IOPcc values were 5.25±1.83, 8.29±2.10, 18.86±2.72 and 20.20±3.37, respectively of the first week after the surgery. The mean CH, CRF, IOPg and IOPcc values were 7.88±1.99, 8.37±1.83, 15.81±2.60 and 16.41±2.80, respectively in the first month after the surgery. Conclusion: These results revealed that the biomechanical properties of the cornea may change during the first one month period after uneventful standard coaxial phacoemulsification surgeryÖğe Evaluation of Pentacam-Scheimpflug imaging of anterior segment parameters in patients with pseudoexfoliation syndrome and pseudoexfoliative glaucoma(Wiley, 2012) Doganay, Selim; Tasar, Ahmet; Cankaya, Cem; Firat, Penpe Gul; Yologlu, SaimBackground: The aim was to evaluate anterior segment parameters in patients with pseudoexfoliation syndrome (PXS) or pseudoexfoliative glaucoma (PXG) with the Pentacam-Scheimpflug imaging system. Methods: Eighty eyes of 53 patients with PXS (Group 1), 80 eyes of 57 patients with PXG (Group 2) and 80 eyes of 45 control cases (Group 3) were included in the study. Anterior chamber depth, volume (ACV), angle (ACA) width, central corneal thickness (CCT), central 3.0, 5.0 and 7.0 mm corneal volumes and pupil diameters were compared between groups. Results: Although anterior chamber depths in the PXG group were significantly lower than the control group (p < 0.05), there was no statistically significant difference between the PXS group and the control group in means of anterior chamber depth values (p > 0.05). There were no statistically significant differences among PXS, PXG and the control group in mean values of ACV, ACA width, CCT, pupil diameters and central 3.0, 5.0 and 7.0 mm corneal volume (p > 0.05). Conclusions: The anterior chamber depths of PXG patients were lower than those of healthy individuals. Although the difference in anterior chamber depth between PXG patients and normal patients was statistically significant, this finding is unlikely to be of clinical significance. The anterior chamber depths of PXS patients were similar to those of healthy individuals. There were no significant differences in the means of ACV, ACA width, CCT, pupil diameter and corneal volume values on central 3.0, 5.0 and 7.0 mm among patients with PXS, PXG and healthy individuals.Öğe Evaluation of the effects of resveratrol and bevacizumab on experimental corneal alkali burn(Elsevier Sci Ltd, 2013) Doganay, Selim; Firat, Penpe Gul; Cankaya, Cem; Kirimlioglu, HalePurpose: To evaluate the effects of resveratrol and bevacizumab on experimental corneal neovascularization. Method: A corneal alkali burn was performed in 62 eyes of 31 male white Vienna rabbits. Resveratrol (group 1), dimethyl sulfoxide (group 2), bevacizumab (group 3) and 0.9% NaCl (group 4) were administered to both eyes of the rabbits by subconjunctival injection for 7 days. Corneal photos were taken at 15 days after alkali injury. Inflammatory index scores and neovascularization areas were calculated. Results: In bevacizumab group both inflammatory index scores and the calculation of the corneal neovascularization area was significantly less than the groups. Conclusion: The subconjunctival administration of bevacizumab inhibits corneal neovascularization effectively in the rabbit corneal alkali burn model. No effect of resveratrol to the corneal neovascularization on experimental model of the corneal alkali burn was seen at the doses of usage. (C) 2012 Elsevier Ltd and ISBI. All rights reserved.Öğe Increased frequency of Demodex blepharitis in rosacea and facial demodicosis patients(Wiley, 2020) Sarac, Gulbahar; Cankaya, Cem; Ozcan, Kubra Nur; Cenk, Hulya; Kapicioglu, Yelda KarincaogluBackground Rosacea is an inflammatory disease with 50% of ocular involvement rate. Primary demodicosis is an eruption caused by Demodex mites, and there is no data about the rate of ocular involvement in primary demodicosis. Aims In this cross-sectional study, it is aimed to reveal the frequency of Demodex blepharitis in rosacea and primary demodicosis patients. Methods In total, 58 rosacea, 33 primary demodicosis patients, and 31 healthy volunteers were included in the study. Four samples were obtained from eyelashes with a forceps and from facial skin by standardized skin surface biopsy. A positive result is described as detecting at least one Demodex mite on an eyelash or at five mites in the face. The patients were also examined by an ophthalmologist in terms of ocular involvement. Results Both rosacea and primary demodicosis patients had significantly more complaints like burning and stinging in the eyes compared to the control patients (P = .001). Primary demodicosis and papulopustular rosacea patients had the highest numbers of eyelash mites, respectively, and significantly a higher rate of blepharitis than the control group. Conclusion As a result, the Demodex count was significantly higher in the primary demodicosis and rosacea patients than the control group. We think that every Demodex-positive patients should be evaluated for also eyelash mites to prevent a possible chronic blepharitis.Öğe Is contrast sensitivity a physiological marker in attention-deficit hyperactivity disorder?(Elsevier, 2020) Donmez, Yunus Emre; Ozcan, Ozlem Ozel; Cankaya, Cem; Berker, Merve; Atas, Pamuk Betul Ulucan; Gunturkun, Pelin Nazli; Ceylan, Osman MelihAttention-deficit hyperactivity disorder (ADHD) is one of the most common childhood-onset psychiatric disorders. Although the etiology is complex and has not yet been clarified, dopamine is thought to play a role in the etiology. Methylphenidate (MPH) is a psychostimulant drug used as first-line treatment for ADHD and it inhibits dopamine and norepinephrine reuptake transporters. Dopamine also has an effect on retina and contrast sensitivity. Despite evidence indicating the effects of dopamine on contrast sensitivity, the results of studies examining contrast sensitivity in ADHD patients are inconsistent. Also, no studies have been encountered examining the possible effect of MPH on contrast sensitivity. The hypotheses of this study are that children with ADHD who have not used MPH will have lower contrast sensitivity levels than the members of the control group, that contrast sensitivity levels increase after the use of MPH, and that contrast sensitivity is a potential physiological marker for ADHD. The study was conducted with 30 children with ADHD and 30 children without ADHD. Psychiatric evaluations of the participants were conducted with the Schedule for Affective Disorders and Schizophrenia for School Age Children-Present and Lifetime-Turkish version, Conner's Parent Rating Scale-Revised Short form and the Turgay DSM-IV-based Child and Adolescent Behavioral Disorders Screening and Rating Scale. Photopic contrast sensitivity was measured using the Functional Acuity Contrast Test (FACT). Results showed that FACT mean values of the control group were significantly higher than those of the ADHD group (pre-treatment) in all spatial frequencies. In four spatial frequencies (CPD 1.5, 3, 12 and 18), the FACT mean values of the control group were significantly higher than the ADHD group (during the OROS-MPH treatment). At all spatial frequencies, the mean values of the ADHD group during the OROS-MPH treatment were significantly higher than before the OROS-MPH treatment. In conclusion, the present study showed that contrast sensitivity is low in children with ADHD and increases significantly after OROS-MPH medication, but still did not reach the levels of the children without ADHD. Our findings suggest that contrast sensitivity may be a potential physiological marker in ADHD.Öğe Outcomes after corneal crosslinking treatment in paediatric patients with keratoconus(Springer, 2024) Cankaya, Cem; Gungor, NurPurposeThis study aims to determine the efficacy and safety of accelerated corneal crosslinking in children with keratoconus.MethodsThe study enrolled 64 patients aged 16 years or younger, each contributing one eye for a total of 64 eyes for analysis. Participants underwent an accelerated form of corneal cross-linking with 15 min of ultraviolet A irradiation at a rate of 7 mW/cm2, resulting in a cumulative energy dose of 5.4 J/cm2. The primary outcome measures were best corrected visual acuity (BCVA) and corneal tomography at 6 and 12 months post-intervention. Parameters assessed included BCVA, spherical and cylindrical refraction, keratometry (K1 and K2), maximum keratometry (Kmax) and thinnest corneal thickness (TCT). These metrics were documented preoperatively and then again at 6 and 12 months postoperatively. In addition, any ocular or systemic conditions related to keratoconus were recorded for each participant.ResultsThe results showed an improvement in BCVA at 12 months after surgery. K1 showed a decrease at both post-operative follow-ups while K2 remained constant throughout the observation period. Kmax showed a notable decrease at the 12 month postoperative follow-up. Although the TCT showed an initial decrease, it reached a stable state after 12 months of crosslinking. Refractive values remained stable at all subsequent examinations. Notably, no complications such as corneal opacity, non-healing epithelial defects or corneal infections occurred during the follow-up period. The most common ocular comorbidity was allergic conjunctivitis (34.4%).ConclusionThe findings suggest that accelerated corneal crosslinking treatment is effective in slowing or halting the progression of keratoconus. Furthermore, there were no persistent overt complications observed at 12 months after the procedure.
