Search

Purpose To compare the corneal hysteresis (CH) and the corneal resistance was increase force (CRF) of patients with age-related macular degeneration (ARMD) and control subjects. Methods The CH and the CRF were compared among 20 patients with ARMD (ARMD group: 10 with neovascular and 10 with non-neovascular ARMD) aged from 54 yrs to 78 yrs (68.9±15.9 yrs) and 20 age-matched control patients (control group). In ARMD and control group the eye's axial length was: 23.14 ±0.95 mm vs. 23.04 ±1.16 mm (p

Purpose To assess the expressibility of the meibomian gland we proposed a new diagnostic tool. We evaluated the use of the instrument by assessing the time of the meibomian gland expressibility and the intraocular pressure change in two groups of healthy patients. Methods We selected two groups of patients divided according to age. The first group consisted of 45 subjects aged between 20 and 30 years (mean 28 ±4.5 yrs) and a second group (group B) of 45 subjects aged between 40 and 50 years (mean 46±3.8 yrs). Meibomian gland evaluations were performed using a standardized technique with an evolved new diagnostic instrument patented in Italy. The instrument has a rectangular contact surface area of 40.57 mm2. The head surface is covered with a plastic film that is changed at each examination. The instrument exerts a constant pressure of 1.2 gr/mm2 under piezoelectric control. We evaluated the time to onset of fluid at the orifices of the meibomian glands and changes of intraocular pressure (IOP) after compression of the lower eyelid with applanation tonometry. Results In the group A and in group B the time to onset the fluid was 3.69±1.22 vs. 6.62±1.39 sec. (p

Purpose To assess corneal hysteresis (CH) and corneal resistance factor (CRF) in keratoconic eyes before and after corneal cross-linking (CXL) with riboflavin/ultraviolet-A and to evaluate the correlation between these biomechanics values and central corneal thickness (CCT). Methods 22 eyes of 12 patients (mean age 25.3±5.9) were evaluated before and 1, 6 and 12 months after CXL. At each visit best corrected visual acuity (BCVA), CCT , CH and CRF using ocular response analyzer-ORA (Reichert Ophthalmic Instruments, Buffalo, NY) were assessed. Data were analyzed using Friedman and Spearman tests. Results BCVA, expressed in LogMAR, significantly improved 1 year after CXL (0.31±0.05 vs 0.27±0.04, p

Purpose To investigate the status of blood-aqueous barrier and to evaluate the subfoveal choroidal thickness (SCT) in patients with chronic never treated hepatitis C virus (HCV) infection without any anterior or posterior ocular disease. Methods A total of 80 eyes of 20 naive HCV patients (M:F=12:8; mean age: 46.9±7.23 years) and 20 healthy controls (M:F=10:10; mean age: 48.2±8.71) were examined. Partecipants underwent a complete ophthalmologic examination. Aqueous flare was objectively quantified by using the non-invasive laser flare cell meter FC 1000 (Kowa, Tokyo, Japan), while SCT was evaluated by using enhanced depth imaging optical coherence tomography (Spectralis OCT; Heidelberg Engineering GmbH). An unpaired t test with Welch correction was performed to compare flare values and SCT between HCV patients and controls, considering significance a p

Purpose We decided to investigate the effects of an acute induced IOP elevation on the prelaminar tissue and on the lamina cribrosa in glaucomatous eyes and in healthy eyes by means of an high resolution Spectral Domain (SD) OCT. Methods We enrolled 10 patients (mean age 70.2 years) affected by primary open angle glaucoma (POAG) and 10 healthy subjects (mean age 70.8 years) as controls. All the subjects were scanned with a SD-OCT with real-time eye tracking at baseline and in the same exact position during IOP elevation performed with an ophthalmodynamometer. The IOP was measured with a Tono-Pen at baseline and during IOP elevation. The SD-OCT images acquired were processed with a computer graphical suite to determine the prelaminar tissue displacement (PTD) and the laminar displacement in the two groups. An analysis of variance was used for evaluating group differences considering statistically significant a P < 0.05. Results Baseline IOP was significantly different in the two groups, with higher values in patients compared to controls: 18.9(4.3) vs. 15.7(2.6) mmHg (P

Purpose Glaucomatous optic neuropathy (GON) is related not only to elevated intraocular pressure (IOP) but also to an insufficient ocular blood supply related to a vascular dysregulation. We evaluated peripheral vascular endothelial function in primary open-angle glaucoma (POAG) with a non-invasive endothelium flow mediated vasodilatation (FMD). Methods We studied 20 POAG patients. The diagnostic criteria for POAG was an IOP exceeded 22 mm/hg before treatment, open anterior chamber angle, cup/disc ratio >0.7 and optic nerve related visual field loss (MD>6 dB, SF>2.5 dB and CPSD>3 dB). Patients with systemic diseases such hypertension, heart failure and diabetes mellitus were excluded. All patients and 20 normal controls underwent measurement of FMD with high-resolution 2-dimensional ultrasonographic imaging of the brachial artery by a Philips ENVISOR echographic machine. To induce iperemia a sphygmomanometer cuff was inflated to 250 mm/hg for 5 minutes. The cuff then was deflated rapidly and at 60 seconds after cuff deflation 2-D images of the brachial artery were recorded for 5 seconds. A statistical analysis was made of the FMD in POAG and in normal control patients using the Student “t” test for unpaired data and the Pearson correlation test to show the correlation between the endothelial dysfunction and the visual field indexes. Results Patients affected by POAG exhibit lower values of FMD compared with healthy people In POAG patients we found an FMD 4,28%±2,49 vs. 8,66%±3,02 (p