Investigative ophthalmology & visual science
-
Invest. Ophthalmol. Vis. Sci. · Nov 2006
The Impact of Vision Impairment Questionnaire: an evaluation of its measurement properties using Rasch analysis.
To explore the psychometric properties of the Impact of Vision Impairment scale (IVI) by using Rasch analysis. ⋯ The results provide support for the measurement properties of the Rasch-scaled 28-item version of the IVI and of its potential for assessing outcomes of low-vision rehabilitation. A raw score-to-Rasch person measure conversion is supplied.
-
Invest. Ophthalmol. Vis. Sci. · Nov 2006
Comparative Study Clinical TrialShort-term effects of latanoprost on anterior chamber depth in patients with glaucoma or ocular hypertension.
Prostaglandin F(2alpha) analogues, such as latanoprost, may cause a decrease in the extracellular matrices, such as collagen, and changes in fibrillin-1; both are components of the ciliary zonules. However, the mechanical effect of these changes on the dynamics of the ciliary zonules is unknown. This study was conducted to evaluate the effect of latanoprost 0.005% on anterior chamber depth (ACD), best corrected visual acuity (BCVA), lens thickness, and anterior chamber dynamics in patients with glaucoma or ocular hypertension. ⋯ These findings suggest that latanoprost decreases ACD in patients with glaucoma or ocular hypertension after 1 month of treatment.
-
Invest. Ophthalmol. Vis. Sci. · Nov 2006
Safety testing of indocyanine green in an ex vivo porcine retina model.
To assess retinal toxicity of indocyanine green (ICG) in a porcine ex vivo perfusion organ culture model, and to measure intraretinal penetration of ICG applied to the retinal surface. ⋯ ICG induced apoptosis but not necrosis in all nuclear retinal layers in a dose-dependent manner. Brief exposure to ICG 0.1% for 1 minute and illumination for 3 minutes simulated the intraoperative use of ICG. No retinal apoptosis or necrosis was observed. ICG briefly applied to the retinal surface gradually penetrated the entire retina.
-
Invest. Ophthalmol. Vis. Sci. · Sep 2006
Vascular endothelial growth factor upregulates expression of ADAMTS1 in endothelial cells through protein kinase C signaling.
ADAMTS1 (a disintegrin and metalloproteinase with thrombospondin motifs) has been demonstrated to inhibit angiogenesis in vivo and to suppress endothelial cell proliferation in vitro. The purpose of this study was to investigate the expression of ADAMTS1 in endothelial cells and in a mouse model of ischemia-induced retinal neovascularization and to study the regulation of ADAMTS1 expression in endothelial cells by vascular endothelial growth factor (VEGF). In addition, the potential function of endothelial cell-derived ADAMTS1 on cell proliferation was investigated. ⋯ These results indicate that VEGF significantly induces ADAMTS1 expression in endothelial cells in a PKC-dependent fashion. ADAMTS1 expression is also increased, along with VEGF expression, in vivo in ischemia-induced retinal neovascularization. In addition, ADAMTS1 appears to be an endogenous regulator of endothelial cell proliferation. Therefore, VEGF upregulation of ADAMTS1, a potent angiogenesis inhibitor, may represent a mechanism for feedback inhibition of angiogenesis and retinal neovascularization.
-
To measure the oscillation phase delay between retinal arterioles and venules in order to analyze pulse wave propagation in the ocular circulation of vasospastic and nonvasospastic subjects and a change thereof during the cold pressor test in another group of healthy subjects. ⋯ Retinal vessels in vasospastic subjects demonstrate an altered pattern of oscillation phase delay between arterioles and venules. Vessels in vasospastic subjects seem to conduct pulse waves faster and are thus stiffer than those in nonvasospastic subjects. The pattern of oscillation demonstrates changes during the cold pressor test in healthy subjects, indicating faster pulse-wave propagation.