Vitrectomy is an ophthalmic microsurgical procedure that removes part or all of the vitreous humor from the eye. The procedure uses a vitreous cutter consisting of a narrow shaft with a small orifice at the end through which the humor is aspirated by an applied suction. An internal guillotine oscillates back and forth across the orifice to alter the local shear response of the humor. In this wo...

PURPOSE Vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, and growth hormone (GH) are major regulators of physical growth, as well as normal and pathologic retinal development. Ocular tissues are protected by the blood-ocular barrier. This study was conducted to test the hypothesis that the ontogenic profiles of VEGF, IGF-I, and GH in the rat serum, vitreous fluid, ...

PURPOSE This study was carried out to compare cytometric bead array (CBA) technology with conventional enzyme linked immunosorbent assay (ELISA) for the measurement of both vitreous and serum concentrations of interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), and angiogenin (ANG) in diabetic and non-diabetic patients. METHODS Measurement of vitreous and serum concentrations of ...

Posterior vitreous detachment is a fairly common condition in elderly people. Tractions exerted by the detached vitreous on the retina may result in retinal tears and detachments. We studied how these tractions can arise from saccadic eye movements. Numerical simulations have been performed on a two-dimensional model of the vitreous chamber within a rigid spherical sclera, subjected to prescrib...

AIM To localise the recently discovered glycoprotein opticin in the adult human eye. METHODS Polyclonal rabbit antisera were raised against two different opticin peptides. Isolated human vitreous collagen fibrils were extracted with 8 M urea and the extract analysed by SDS-PAGE and western blotting. Paraffin embedded sections from two normal eyes were subjected to immunohistochemical analysis...

The purpose of this study was to compare steroid hormone concentration levels in the vitreous and serum of vitreoretinal disease patients to elucidate the possibility of neurosteroid production in the retina. Serum and vitreous samples were collected from vitrectomy patients, and estradiol (E2) and testosterone (T) concentrations were measured using electro-chemiluminescence immunoassay. We mea...

The disposition of ISIS 2922, a phosphorothioate oligonucleotide for treatment of cytomegalovirus associated retinitis, was evaluated in rabbits. Vitreous humor and retina samples were collected from rabbits that received a single intravitreal injection of 66 microg [14C]-labeled ISIS 2922 and were analyzed using anion exchange HPLC. Four hr postdosing, the concentration of ISIS 2922 in vitreou...

PURPOSE Atrial natriuretic peptide (ANP) has been recently described as an endogenous inhibitor of the synthesis and angiogenic action of vascular endothelial growth factor (VEGF). Given VEGF's key role in promoting neovascularization in proliferative diabetic retinopathy (PDR), this study was designed to evaluate the possibility that ANP could be involved in the neovascular and fibrotic compli...

This retrospective observational case series on eyes from three patients was done to elucidate the developmental mechanism of spontaneous reattachment of rhegmatogenous retinal detachment (SRRRD). The study eyes of each patients showed evidence of retinal break and diffuse retinal pigmentary change. Ultrasound biomicroscopic examination revealed vitreous fibers attached to the area around the r...

purpose: to report the rate of vitreous loss during phacoemulsification and its contributing risk factors in patients operated on at labbafinejad medical center.  methods: this prospective comparative descriptive study included patients with cataract undergoing phacoemulsification by ophthalmology residents or cornea fellows from november 2006 to november 2007. all patients underwent a complete...