Main Principles of Vitrectomy Using Intraocular Tamponades - A Basic Course in Surgery.

This article is intended to clearly present the basic principles for the use of intraocular tamponades in vitreous/retinal surgery in the event of retinal detachment and other pathologies using additional video footage. It examines the various gases, silicone oils and perfluorocarbon liquids with their indications, administration and in particular intraoperative handling including pitfalls and complications. Characteristic animations show the principles of use in surgery in a comprehensible way.

Spatial resolution and perception of patterns mediated by a subretinal 16-electrode array in patients blinded by hereditary retinal dystrophies.

Purpose: The perception of 11 persons blinded by hereditary retinal degeneration elicited by a subretinally implanted 16-electrode array used for light-independent direct stimulation of the retina is described. This device is part of the Tübingen retina implant, which also employs a light-sensitive, multiphotodiode array (MPDA). The ability to reliably recognize complex spatial percepts was investigated.

Different collagen types define two types of idiopathic epiretinal membranes.

Aims: To identify differences in extracellular matrix contents between idiopathic epiretinal membranes (IEM) of cellophane macular reflex (CMRM) or preretinal macular fibrosis (PMFM) type.

Methods And Results: Idiopathic epiretinal membranes were analysed by light and quantitative transmission electron microscopy, immunohistochemistry and Western blotting. Substantial differences between CMRM and PMFM were observed regarding the nature of extracellular fibrils.

The outcome of early surgical repair with vitrectomy and silicone oil in open-globe injuries with retinal detachment.

Purpose: To determine the functional and anatomic outcome of early surgical repair with vitrectomy and silicone oil in open-globe injuries with retinal detachment (RD).

Design: Retrospective consecutive interventional case series.

Methods: All patients with open-globe injuries with RD treated between 1997 and 2007 underwent primary repair including vitrectomy with silicone oil within 8 hours after presentation.

Subretinal electronic chips allow blind patients to read letters and combine them to words.

A light-sensitive, externally powered microchip was surgically implanted subretinally near the macular region of volunteers blind from hereditary retinal dystrophy. The implant contains an array of 1500 active microphotodiodes ('chip'), each with its own amplifier and local stimulation electrode. At the implant's tip, another array of 16 wire-connected electrodes allows light-independent direct stimulation and testing of the neuron-electrode interface.

Management of submacular hemorrhage with intravitreal versus subretinal injection of recombinant tissue plasminogen activator.

Aim: To compare the efficacy of pars plana vitrectomy (ppV) with intravitreal injection of recombinant tissue plasminogen activator (rtPA) and gas versus ppV with subretinal injection of rtPA and intravitreal injection of gas.

Methods: Nonrandomized, retrospective, interventional, comparative consecutive series including 47 patients with submacular hemorrhage. Eighteen patients were treated with ppV, intravitreal injection of rtPA and 20% SF6 gas [group A: mean age 78 years, mean duration of symptoms 6.

Maintenance of adult porcine retina and retinal pigment epithelium in perfusion culture: characterisation of an organotypic in vitro model.

The purpose of this study was to characterise an ex-vivo adult porcine retina-retinal pigment epithelium (RPE) perfusion organ culture model. Fresh porcine full-thickness retina-RPE-choroid tissue samples were clamped into tissue carriers and mounted in two-compartment containers. The retinal and choroidal sides were continuously perfused with culture medium.

Long-term safety and functional outcome of combined pars plana vitrectomy and scleral-fixated sutured posterior chamber lens implantation.

Purpose: To investigate the complication profile and the long-term functional outcome of combined pars plana vitrectomy and scleral-fixated sutured posterior chamber lens (PC IOL) implantation.

Design: Retrospective, consecutive, interventional case series.

Methods: The records of 63 patients (mean age, 67.

Ascorbic acid modulates proliferation and extracellular matrix accumulation of hyalocytes.

Ascorbic acid is known to influence proliferation and functional properties of several cell types and is therefore widely used in tissue engineering. In this study, the effect of ascorbic acid on the proliferation and functional properties of hyalocytes was evaluated. Hyalocytes were cultured with different amounts of ascorbic acid in classical two-dimensional (2-D) cultures and a three-dimensional (3-D) pellet culture system.

Retreatment of full-thickness macular hole: predictive value of optical coherence tomography.

Aim: To determine whether the efficacy of re-operation for idiopathic full-thickness macular hole (FTMH) remaining open after initial surgery with internal limiting membrane (ILM) peeling is correlated with macular hole configuration as determined by optical coherence tomography (OCT), macular hole size, macular hole duration before the first operation, or type of tamponade (gas or silicone oil).

Methods: A retrospective consecutive interventional case series of 28 patients (28 eyes) with a persisting macular hole after vitrectomy, ILM peel, and gas tamponade. 28 patients underwent repeat surgery involving vitrectomy and gas (n = 15) or silicone oil tamponade (n = 12) or no tamponade (n = 1).

Surgical removal of idiopathic epiretinal membrane with or without the assistance of indocyanine green: a randomised controlled clinical trial.

Purpose: To carry out a prospective investigation of the functional and morphological outcome of idiopathic epiretinal membrane (IEM) surgery with or without the assistance of indocyanine green (ICG) in a randomised controlled clinical trial.

Methods: Sixty patients who underwent vitrectomy with removal of IEM combined with cataract surgery were randomly allocated to two groups: 27 patients were operated on with ICG 0.1% in glucose 5%, 33 patients without ICG.

Optical coherence tomography findings in idiopathic juxtafoveal retinal telangiectasis.

Purpose: To describe optical coherence tomography (OCT) findings in patients with juxtafoveal retinal telangiectasis (JRT).

Methods: Fourteen consecutive patients (28 eyes) with JRT (12 patients with JRT type II, one with JRT type I and one with JRT type III) were examined using fluorescein angiography (FA) and OCT.

Results: Despite prominent leakage in FA, macular oedema was absent in all 26 eyes with type II JRT.

Safety testing of indocyanine green in an ex vivo porcine retina model.

Purpose: 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.

Methods: The retinal surface of fresh porcine retinal tissue was exposed to ICG 0.1% and 1% dissolved in glucose 5% for 1 and 30 minutes with and without concomitant illumination.

Fundus autofluorescence before and after photodynamic therapy for choroidal neovascularization secondary to age-related macular degeneration.

Background And Objective: To describe fundus autofluorescence patterns in choroidal neovascularization secondary to age-related macular degeneration before and after photodynamic therapy (PDT).

Patients And Methods: Sixty-eight consecutive eyes were indicated for PDT after standard fluorescein angiography, which showed completely classic choroidal neovascularization (CNV) (n=52), occult with no classic CNV (n=7), and predominantly classic CNV (n=9). Standardized PDT was performed and patients were examined 2 to 3 months later.

Keratocyte density in the retroablation area after LASEK for the correction of myopia.

Purpose: During excimer laser photoablation keratocyte cell death is induced in the retroablation area. Afterwards this area is repopulated by keratocyte mitosis and migration from the adjacent stroma. The aim of this study was to investigate keratocyte density in the retroablation area and in the posterior stroma during the first year after LASEK for the correction of myopia.

Correlation between optical coherence tomography and autofluorescence in acute posterior multifocal placoid pigment epitheliopathy.

Purpose: To report a case of bilateral acute posterior multifocal placoid pigment epitheliopathy (APMPPE) evaluated by optical coherence tomography (OCT), fundus autofluorescence (AF) and microperimetry, both in the acute phase and after resolution of symptoms.

Methods: Complete ophthalmological evaluation, including fluorescein angiography, OCT, AF, and microperimetry upon presentation and 1 month later, after lesions have subsided. An attempt to correlate the findings on presentation and changes after resolution is performed using the results of these new investigational techniques.

Preferential Hyperacuity Perimeter (PreView PHP) for detecting choroidal neovascularization study.

Purpose: To assess the ability of the Preferential Hyperacuity Perimeter (PreView PHP; Carl Zeiss Meditec, Dublin, CA) to detect recent-onset choroidal neovascularization (CNV) resulting from age-related macular degeneration (AMD) and to differentiate it from an intermediate stage of AMD.

Design: Prospective, comparative, concurrent, nonrandomized, multicenter study.

Participants: Eligible participants' study eyes had a corrected visual acuity of 20/160 or better and either untreated CNV from AMD diagnosed within the last 60 days or an intermediate stage of AMD.

[The influence of ionizing radiation on the development of posterior capsule opacification in vitro].

Background And Purpose: Histologically, the posterior capsule opacification (PCO) corresponds to regenerative tissue of transformed lens epithelial cells (LECs) with extracellular matrix production. In this study, the influence of ionizing radiation on proliferating LECs and the development of PCO was investigated in vitro.

Material And Methods: Each four and 14 pork lenses, respectively, were irradiated with 6 MeV electrons with single doses of 8, 10, 12, and 20 Gy.

Von Willebrand's disease type I as a cause for subvitreal, retinal and subretinal haemorrhages.

Background: Young patients with vitreous, retinal and subvitreal haemorrhages without neovascularisation or prior trauma are a diagnostic challenge for the physician. In this case report, a patient is presented who developed unilateral, spontaneous, subvitreal, retinal and subretinal haemorrhages and was diagnosed with von Willebrand's disease.

Case Report: A 33-year-old Caucasian woman presented at our clinic with unilateral subvitreal, retinal and subretinal haemorrhages.

Fundus autofluorescence in acute and chronic-recurrent central serous chorioretinopathy.

Purpose: Central serous chorioretinopathy (CSC) affects mostly young and middle-aged adults. Typically, a serous retinal detachment occurs with a focal leakage point in fluorescein angiography. Fundus autofluorescence (AF) is related to the lipofuscin within the retinal pigment epithelium (RPE).

Retinal replacement--the development of microelectronic retinal prostheses--experience with subretinal implants and new aspects.

Background: Progress in the field of microelectronics has led to the development of visual prostheses for the treatment of blinding diseases. Different concepts of retinal replacement are currently under investigation. The aim of the retinal prostheses is to replace the function of lost photoreceptors in degenerative diseases, such as retinitis pigmentosa.

Clinical findings on the use of long-term heavy tamponades (semifluorinated alkanes and their oligomers) in complicated retinal detachment surgery.

Background: Heavy tamponades for pathologies in the lower part of the retina are a new development, and different tamponades have recently come into clinical use: semifluorinated alkanes (F(6)H(6), F(6)H(8)) and their oligomers (OL62HV).

Method: Nine patients had been operated on using F(6)H(8) (n=5) and by OL62HV (n=4). In all cases the reasons for using the tamponades were complicated retinal detachments in the lower part.

What is the meaning of threshold in laser injury experiments? Implications for human exposure limits.

The derivations of human exposure limits for laser radiation rely heavily upon experimental ocular injury studies. The limits are derived by committees of ophthalmic experts through a review of all available threshold data and an understanding of mechanisms of laser/tissue interaction. A major point of discussion in this derivation process relates to the level of uncertainty of the threshold of injury.