ABSTRACT
BACKGROUND: The aim of this work was to investigate the differences in corneal biomechanical parameters between healthy and exfoliation syndrome (EXS) and exfoliative glaucoma (EXG) patients. METHODS: Two hundred and forty-four eyes of 102 healthy, 64 EXS, and 78 EXG patients were included in the study. Corneal biomechanical parameters were measured using an ocular response analyzer (ORA). Central corneal thickness (CCT) was measured with an ultrasonic pachymeter. The differences in ORA parameters between study and control group participants were analyzed using Student's t test. RESULTS: In healthy subjects, EXS and EXG eyes mean corneal hysteresis (CH) values were 9.4 ± 1.4 mmHg, 8.5 ± 1.5 mmHg and 6.9 ± 2.1 mmHg, respectively. The difference in mean CH between the EXG and the other two groups were statistically significant (p < 0.01 for both comparisons). CH was significantly lower in EXS patients than that of healthy eyes (p < 0.001). Mean corneal resistance factor (CRF) values were 9.8 ± 1.6 mmHg, 9.3 ± 1.8 mmHg and 9.5 ± 2.6 mmHg, respectively. Except for the difference between the control and EXS eyes (p = 0.004), no statistically significant difference was found between the groups in relation to mean CRF. There were no significant differences in CCT between the control eyes and exfoliative eyes with or without glaucoma. CONCLUSIONS: In this study, CH was found to be significantly lower in eyes with exfoliation. Further studies are needed to establish the relationships between exfoliation, ocular biomechanics, and glaucoma.
Subject(s)
Cornea/physiology , Diagnostic Techniques, Ophthalmological/instrumentation , Elasticity/physiology , Exfoliation Syndrome/physiopathology , Glaucoma, Open-Angle/physiopathology , Aged , Biomechanical Phenomena , Cornea/diagnostic imaging , Cross-Sectional Studies , Female , Gonioscopy , Humans , Intraocular Pressure/physiology , Male , Tonometry, Ocular , UltrasonographyABSTRACT
PURPOSE: To evaluate the short-term effects of intravitreal bevacizumab on retrobulbar hemodynamics in patients with neovascular age-related macular degeneration (AMD). METHODS: This study was carried out at Ataturk Training and Research Hospital 1st Ophthalmology Clinic, Ankara. Fourteen patients with neovascular AMD, who were treated with intravitreal injection of bevacizumab, were included in this study. Peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistivity index (RI) were measured with colour Doppler imaging (CDI) in the ophthalmic artery, central retinal artery (CRA) and posterior ciliary artery. RESULTS: The mean age of the 14 patients was 78 ± 9 (64-87). Of the 14 patients, eight were men and six were women. Colour Doppler imaging measurements of EDV (p = 0.015) and RI (p = 0.009) parameters of CRA revealed statistically significant difference among all three periods. End-diastolic velocity values decreased at the end of the 1st week and returned close to preoperative values at the end of the 1st month after the procedure. Also, EDV of posterior ciliary artery (PCA) decreased at the end of the 1st week and returned close to preoperative values at the end of the 1st month after the procedure. Resistivity index of PCA showed a temporary increase at the end of the 1st week and returned close to preoperative values at the end of the 1st month after the procedure. CONCLUSION: Injection of bevacizumab decreased blood velocities of CRA and PCA and increased RI of CRA and PCA in the early postoperative period and returned to preoperative values at the end of the first month.
Subject(s)
Antibodies, Monoclonal/administration & dosage , Choroidal Neovascularization/physiopathology , Ciliary Arteries/physiology , Eye/blood supply , Macular Degeneration/physiopathology , Ophthalmic Artery/physiology , Retinal Artery/physiology , Aged , Aged, 80 and over , Angiogenesis Inhibitors/administration & dosage , Antibodies, Monoclonal, Humanized , Bevacizumab , Blood Flow Velocity/drug effects , Choroidal Neovascularization/diagnostic imaging , Choroidal Neovascularization/drug therapy , Female , Hemodynamics/physiology , Humans , Intravitreal Injections , Macular Degeneration/diagnostic imaging , Macular Degeneration/drug therapy , Male , Middle Aged , Ultrasonography, Doppler, Color , Vascular Endothelial Growth Factor A/antagonists & inhibitorsABSTRACT
PURPOSE: To investigate the effects of high-permeability silicone hydrogel contact lenses used for therapeutic purposes on limbal cells, inflammation, and neovascularization. METHODS: Bullous keratopathy was induced by injection of 0.05% benzalkonium chloride into the anterior chamber of 20 anesthetized rabbit eyes. Ten-millimeter diameter central epithelial erosions were produced, and silicone hydrogel contact lenses were applied onto 10 corneas. Nasal and temporal tarsorrhaphy was performed to leave the central corneal area open. On the 15th and 30th days, the corneas were extracted and examined under electron and light microscopy. RESULTS: Electron microscopy showed no prominent stress-induced findings in limbal cells in the contact lens group. Epithelial edema was reduced in this group, but on the 30th day, the epithelial edema was greater than that observed on the 15th day. Evaluation of polymorphonuclear and eosinophilic cell infiltration by light microscopy showed that inflammation was less in corneas without contact lenses and the inflammation grade was the same on the 15th and 30th days. Neovascularization was similar in both groups. CONCLUSIONS: The therapeutic use of silicone hydrogel lenses would probably have no effect or, at most, only a slight adverse morphologic effect on limbal area cells. However, when the effects on edema and inflammation were taken into consideration, a 15-day period of wear may be preferable to a 30-day period.
