Browsing by Subject "central corneal thickness"

Now showing 1 - 6 of 6
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    Surgically induced changes in corneal viscoelastic properties after 23-gauge pars plana vitrectomy using ocular response analyzer
    (2013) Seymenoǧlu G.; Uzun Ö.; Başer E.
    Purpose: To evaluate surgically induced changes in corneal viscoelastic properties of patients undergoing 23-gauge transconjunctival sutureless vitrectomy (23-G TSV). Methods: The study group consisted of 29 eyes of 29 patients undergoing 23-G TSV. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), corneal compensated intraocular pressure (IOPcc) and central corneal thickness (CCT) were measured by ocular response analyser (ORA), preoperatively and 1 and 3 months postoperatively. Goldmann applanation tonometry (GAT) was also performed in the same time periods. The ORA measurements before and after the surgery were compared statistically. In addition, the ORA measurements of a control group comprising of 29 normal subjects were also compared with the preoperative measurements of the patient group. Finally the relationship between the CH values and the CCT and GAT values was also assessed. Results: The preoperative ORA measurements of the study group were similar to those of the control groups' (p > 0.05 for all). In the study group, mean CH decreased and mean IOPcc increased significantly at 1 month compared with their respective preoperative values (p = 0.04 and p = 0.03, respectively). However CH and IOPcc measurements at 3 months were similar to the preoperative measurements (p > 0.05). Mean CRF, IOPg, GAT and CCT measurements did not change significantly during the study period (p > 0.05). CH was weakly correlated with CCT preoperatively, 1 and 3 months postoperatively (r = 0.33, r = 0.33, r = 0.43, p < 0.05 for all, respectively). There was also a weak but significant correlation between CH and GAT preoperatively (r = 0.42, p = 0.008), 1 month postoperatively (r = 0.36, p = 0.03), 3 months postoperatively (r = 0.40, p = 0.01). Conclusion: Corneal viscoelastic properties are not significantly influenced in the late postoperative period by 23-G TSV which is a minimal invasive vitreoretinal surgical technique. © 2013 Informa Healthcare USA, Inc.
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    Influence of tamsulosin on the anterior segment parameters and central corneal thickness; [Tamsulosinin ön segment parametreleri ve santral kornea kali{dotless}nli{dotless}ǧi{dotless}na etkisi]
    (Turkiye Klinikleri, 2014) Palamar M.; Emre S.; Turna B.; Yaǧci A.
    Objective: To investigate the effects of tamsulosin (α-1 adrenergic receptor antagonist) on the main numerical parameters of anterior segment using Pentacam rotating Scheimmpflug camera, and on biomechanical parameters using Reichert Ocular Response Analyser (ORA) in patients with benign prostate hyperplasia. Material and Methods: In addition to full eye examination [best corrected visual acuity, keratometry, intraocular pressure (IOP) measured with Goldmann applanation tonometry], Pentacam [central corneal thickness (CCT), anterior chamber depth, anterior chamber volume, anterior chamber angle, pupil diameter] and ORA (corneal hysteresis, corneal resistance factor, corneal compensated IOP, Goldmann correlated IOP) measurements of 30 eyes of 15 male patients were performed before and one month after tamsulosin therapy. Paired t-test and non-parametric Wilcoxon test were used for comparisons. Results: Mean age in the study group was 61.50±6.10 (range 47-69) years. After tamsulosin treatment, CCT increased and this increment was statistically significant (p=0.002). None of the other parameters that were evaluated showed statistically significant difference after tamsulosin use. Conclusion: Tamsulosin leads to significant increment in CCT. The effects of tamsulosin on CCT should be taken into consideration for proper clinical interpretation in patients using tamsulosin. © 2014 by Türkiye Klinikleri.
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    A multimodal ophthalmic analysis in patients with systemic sclerosis using ocular response analyzer, corneal topography and specular microscopy
    (Springer, 2020) Mayali H.; Altinisik M.; Sencan S.; Pirildar T.; Kurt E.
    Purpose: To conduct a multimodal ophthalmic evaluation of systemic sclerosis (SSc) in patients using ocular response analyzer (ORA), Pentacam, and specular microscopy (SM). Methods: Thirty-one SSc patients and a group of age- and sex-matched controls were enrolled in this cross-sectional study. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with ORA. Anterior chamber depth (ACD), central corneal thickness (CCT), and corneal volume (CV) measurements were obtained using Pentacam. Corneal endothelial cell density (ECD) and CCT were evaluated by SM. Results: SSc patients had significantly lower CH, ACD, and ECD values compared to the control group (p = 0.018; < 0.001; < 0.001, respectively). There was no significant difference regarding CRF, IOP, CV, or CCT measurements acquired by Pentacam and SM. Regarding CCT, SM and Pentacam showed relatively better agreement in SSc patients. Conclusions: Multimodal imaging can provide more comprehensive and useful information regarding the ocular involvement of systemic diseases. The multimodal evaluation in our study demonstrated that the pathologic effects of SSc may manifest as reductions in ACD, corneal elasticity, and ECD before there are any detectable changes in corneal thickness or IOP. © 2019, Springer Nature B.V.
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    Comparison of central corneal thickness measurements by contact and non-contact pachymetry devices
    (Jaypee Brothers Medical Publishers (P) Ltd, 2021) Mayali H.; Altinisik M.; Diri I.; Ilker S.; Kurt E.; Kayikcioglu O.
    Aim and objective: To compare central corneal thickness (CCT) measurements obtained by handheld contact ultrasound pachymetry (HCUP) and non-contact pachymetry devices. Materials and methods: Ninety eyes of 90 patients (52 male and 38 female) were included in the study. Measurements from two non-contact devices, —specular microscopy (SM, Konan Medical, CA, USA) and Oculus Pentacam (Oculus Inc., Germany)—were compared against HCUP (Pachmate 2, DGH Technology, Inc, PA, USA). Ultrasound measurements were obtained 3 times by the same user and averaged. The differences were calculated by one-way ANOVA. Agreement between measurements were assessed by Bland–Altman plots and intraclass correlation coefficient tests. Coefficient of repeatability (%, CR) was defined as 1.96*standard deviations of the differences between pairs of measurements divided by the average of the means. Results: The mean age was 34.31 ± 14.39 (14–74) years, and the mean intraocular pressure was 16.48 ± 2.63 mm Hg (12–21). Mean CCT measured by HCUP, SM, and Pentacam was 557.76 ± 36.76 μm, 550.29 ± 43.74 μm, and 541.41 ± 35.7 μm, respectively (p < 0.05). In the Bland–Altman plot, 95% limit of agreements were 19.5 and 14.18 μm among HCUP measurements, 34.55 μm between HCUP and Pentacam, 41.49 μm between SM and Pentacam, and 46.98 μm between HCUP and SM. CR values (%) were 3.49, 2.54, 6.28, 7.68, and 8.47, respectively. Conclusion: There were significant differences between the mean CCT values of the measurement devices. Clinical significance: Contact and non-contact devices may not interchangeable in the clinical assessment of CCT. © Jaypee Brothers Medical Publishers. 2021 Open Access.
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    Multimodal ocular evaluation in hemodialysis patients
    (Springer Science and Business Media B.V., 2021) Mayali H.; Altinisik M.; Sarigul C.; Toraman A.; Turkoglu M.S.; Kurt E.
    Purpose: To evaluate choroidal thickness, intraocular pressure (IOP), axial length, central corneal thickness (CCT), lens thickness, anterior chamber depth, and ocular pulse amplitude (OPA) in hemodialysis patients. Materials and methods: The patients with end-stage renal disease and undergoing hemodialysis were included in the study. Immediately before and 1 hour after hemodialysis, all patients underwent measurement of choroidal thickness with spectral domain optical coherence tomography (SD-OC, Cirrus HD-OCT; Carl Zeiss Meditec Inc., Dublin, CA), IOP and OPA with Pascal dynamic contour tonometry (Ziemer Ophthalmic Systems AG, Port, Switzerland), and anterior chamber depth, lens thickness, and axial length with optical biometry (LenStar LS900; Haag-Streit AG, Koeniz, Switzerland). Data from the patients’ right eyes were included in the statistical analysis. Results: The patient group included 8 (36.4%) males and 14 (63.6%) females with a mean age of 56, 14 ± 9, 96 (40–70) years. The mean subfoveal choroidal thickness before and after hemodialysis was 255.21 ± 6.15 (245–263) µm and 234.95 ± 7.89 (220–247) µm, respectively (p < 0.001). Mean choroidal thickness at 1500 µm and 3000 µm nasal and temporal of the fovea also decreased significantly after hemodialysis (p < 0.001). Mean OPA values before and after hemodialysis were 2.14 ± 1.07 (0.6–4) mmHg and 1.6 ± 0.86 (0.5–3.2) mmHg, respectively (p < 0.001). There was a statistically significant correlation between OPA and choroidal thickness measurements (p < 0.001, R = 0.923). IOP increased from 15.11 ± 2.58 (11–20) to 15.99 ± 2.21 (13–20) mmHg, but the change did not reach statistical significance (p = 0.05). There was no statistically significant change in mean axial length, anterior chamber depth, lens thickness, or CCT after hemodialysis (p > 0.05 for all). Conclusion: Although choroidal thickness and OPA may be decreased immediately after hemodialysis, there may be no significant changes in IOP or avascular ocular structures such as the lens and cornea. © 2021, The Author(s), under exclusive licence to Springer Nature B.V.
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    Corneal endothelial damage in phacoemulsification using an anterior chamber maintainer compared with using an ophthalmic viscosurgical device
    (Lippincott Williams and Wilkins, 2021) Mayali H.; Baser E.F.; Kurt E.; Ilker S.S.
    Purpose: To compare the effects of phacoemulsification surgery (PE) using an anterior chamber maintainer (ACM) and conventional PE using an ophthalmic viscosurgical device (OVD) on corneal endothelial cells. Setting: Department of Ophthalmology, Celal Bayar University, Manisa, Turkey. Design: Prospective randomized controlled trial. Methods: Eyes in the OVD group (n = 50) underwent conventional PE, whereas eyes in the ACM group (n = 50) underwent PE using an ACM. Endothelial cell density (ECD), coefficient of variation (CV), hexagonality (HEX), and noncontact central corneal thickness (CCT) measurements were performed by specular microscopy before and at 1 month, 3 months, and 6 months after PE. Results: This study included 100 eyes of 97 patients undergoing PE. The mean age was 64.7 ± 10.6 years in the OVD group, 64.0 ± 12.6 years in the ACM group (P >.05). The groups did not differ significantly in preoperative ECD, CV, HEX, and CCT or total PE time (P >.05 for all). ECD was significantly lower in the ACM group compared with the OVD group at postoperative 1 month, 3 months, and 6 months (P =.002, P =.002, and P =.001, respectively). Similarly, ECD loss compared with preoperative value was greater in the ACM group at all postoperative timepoints (P =.003, P =.001, and P =.001, respectively). CV increased and HEX decreased in both groups postoperatively (P >.05 for both). CCT showed a transient increase of less than 10 m at postoperative 1 month in both groups (P =.296). Conclusions: PE with ACM was associated with greater corneal ECD loss compared with conventional PE. ACM should not be used during PE in patients with limited corneal endothelial reserve. © 2021 Elsevier Inc.. All rights reserved.