Visualising vitreous through modified trans-scleral illumination by maximising the Tyndall effect

Background: A new technique for visualisation of the vitreous base is described. It uses a standard lightpipe for scleral indentation and transillumination. Visualisation of the vitreous using low light levels can be achieved by enhancing the Tyndall effect. Discussion: Perfluorocarbon liquid (PFCL) is used to confine the aqueous environment to the anterior vitreous cavity and triamcinolone is added to increase light scatter. The technique clearly differentiates vitreous from PFCL and infusion fluid, and facilitates trimming of the vitreous base, draining of subretinal fluid and air/fluid exchange.published_or_final_versio

Transthyretin levels in the vitreous correlate with change in visual acuity after vitrectomy

Background/aim: Little is known about biochemical markers related to change in visual acuity after vitrectomy. The potential use of transthyretin (TTR), a carrier of the retinol/retinol-binding protein, as a biochemical marker protein, was investigated. Methods: TTR was measured using immunonephelometry in a group of patients (n = 77) in longstanding (> 1 week) retinal detachment (n = 29), fresh (< 1 week) retinal detachment (n = 17), macular holes (n = 20) or diabetic retinopathy (n = 11). Vitreous samples were taken at the start of every vitrectomy procedure. For reference values, cadaver specimens (n = 73) were used. Results: Reference values for vitreous TTR (median 18 mg/l; IQR 4 to 24 mg/l) comprised 2.2% of reference values for vitreous protein levels (median 538 mg/l; IQR 269 to 987 mg/l). Vitreous TTR values of patients were comparable in all disorders. Vitreous TTR values were higher in phakic (median 22.5 mg/l; IQR 10 to 27 mg/l) than in pseudophakic patients (median 12 mg/l; IQR 8 to 19 mg/l; p = 0.06). Postoperative change in visual acuity correlated well with vitreous TTR values found peroperatively (r(s) = 0.408; p = 0.012). Both change in visual acuity and lens status were the only variables which proved to explain the variance of TTR (multiple correlation coefficient: 0.494; phakic status: t = 2.767; p = 0.0084; and change in visual acuity t = 2.924: p = 0.0056). Conclusion: Vitreous fluid concentrations of TTR can be regarded as a biochemical marker for retinal function

The effect of a preoperative subconjuntival injection of dexamethasone on blood–retinal barrier breakdown following scleral buckling retinal detachment surgery: a prospective randomized placebo-controlled double blind clinical trial

textabstractBackground: Blood-retinal barrier breakdown secondary to retinal detachment and retinal detachment repair is a factor in the pathogenesis of proliferative vitreoretinopathy (PVR). We wished to investigate whether an estimated 700 to 1000 ng/ml subretinal dexamethasone concentration at the time of surgery would decrease the blood-retinal barrier breakdown postoperatively. Methods: Prospective, placebo-controlled, double blind clinical trial. In 34 patients with rhegmatogenous retinal detachment scheduled for conventional scleral buckling retinal detachment surgery, a subconjunctival injection of 0.5 ml dexamethasone diphosphate (10 mg) or 0.5 ml placebo was given 5-6 hours before surgery. Differences in laser flare photometry (KOWA) measurements taken 1, 3 and 6 weeks after randomisation between dexamethasone and placebo were analysed using mixed model ANOVA, while correcting for the preoperative flare measurement. Results: Six patients did not complete the study, one because of recurrent detachment within 1 week, and five because they missed their postoperative laser flare visits. The use of dexamethasone resulted in a statistically significant decrease in laser flare measurements at the 1-week postoperative visit. Conclusion: The use of a preoperative subconjunctival injection of dexamethasone decreased 1-week postoperative blood-retina barrier breakdown in patients undergoing conventional scleral buckling retinal detachment surgery. This steroid priming could be useful as a part of a peri-operative regime that would aim at decreasing the incidence of PVR

Characterization of the Primo-Vascular System in the Abdominal Cavity of Lung Cancer Mouse Model and Its Differences from the Lymphatic System

Cancer growth and dissemination have been extensively studied for a long time. Nevertheless, many new observations on anatomy and histopathology of cancer events are still reported such as formation of a vasculogenic-like network inside aggressive tumors. In this research, new kinds of micro-conduits, named primo-vessels, were found inside the abdominal cavity of NCI-H460 lung cancer murine xenograft models. These vascular threads were largely distributed on the surfaces of various organs and were often connected to peritoneal tumor nodules. Histological and immunofluorescent investigations showed that the primo-vessels had characteristic features that were distinctively different from those of similar-looking lymphatic vessels. They had multiple channels surrounded with loose collageneous matrices, which is in contrast to the single-channel structure of other vascular systems. The rod-shaped nuclei aligned longitudinally along the channels were assumed to be the endothelial cells of the primo-vessels, but LYVE-1, a specific marker of lymphatics, was not expressed, which indicates a clear difference from lymphatic endothelial cells. Taken together these findings on and characterization of the novel threadlike vascular structures in cancer models may have important implications for cancer prognosis and for therapy

Active removal of anterior segment-migrated dexamethasone implant (Ozurdex®)

Background: Ozurdex® (Allergan plc., Dublin, Ireland) is an intravitreal sustained-release dexamethasone (DEX) implant. The implant has been reported to migrate into the anterior chamber, potentially causing corneal decompensation. Prompt removal or relocation in the vitreous cavity is advised but troublesome due to its fragility. Several techniques exist, but elaborate setup and specialized surgical skills that are required may cause delay in treatment. We report a novel technique that avoids these shortcomings.Case presentation: A 59-year-old woman presented to the emergency department with visual loss due to an anterior chamber-migrated DEX implant and corneal edema. Using an ophthalmic viscosurgical device (OVD) and a bent 19-gauge needle, the implant has promptly been removed in a one-minute procedure under topical anesthesia.Conclusion: Aspirating an anterior chamber-migrated DEX implant using a 19-gauge bent needle is a cost-effective, time-efficient and safe technique, not requiring specialized surgical skills

Autologous full-thickness RPE-choroid graft to treat high-risk drusenoid pigment epithelial detachment without CNV

Objective: To report on the survival of a retinal pigment epithelium (RPE)-choroid graft translocated to treat a patient with drusenoid pigment epithelial detachment (DPED).Methods: We describe a patient with bilateral high-risk DPED where one eye was treated with RPE-choroid translocation surgery and followed up for more than two years.Results: The RPE-choroid graft surgery was straightforward and the fully perfused graft was able to support stable vision of 0.5 Snellen acuity for more than two years despite the development of a choroidal neovessel at the edge of the graft. The vision in the fellow eye dropped from 0.5 to 0.2 Snellen in the same period.Conclusion: RPE-choroid translocation may slow the progression of DPED to atrophy but it can also transform dry age-related macular degeneration (AMD) into neovascular AMD

Deferred laser photocoagulation of relaxing retinotomies under silicone oil tamponade to reduce recurrent macular detachment in severe proliferative vitreoretinopathy

Purpose This study sought to investigate whether, in patients with retinal detachment complicated by proliferative vitreoretinopathy, we can re-attach the retina with a posterior relaxing retinotomy and silicone oil tamponade while postponing laser retinopexy for several months. Methods In 13 consecutive patients we applied laser coagulation of the retinotomy edge 15 +/- 12 weeks after surgery. Silicone oil was removed 9 +/- 6 weeks after laser application. Results After the retinotomy without laser, some degree of central shifting was seen in all patients, followed by obvious curling in 10 patients. The total follow-up was 24 +/- 7 months after retinotomy and 13 +/- 9 months after oil removal. The retina was attached in 12 patients at the last visit, with the oil still in situ in three patients. Seven patients, however, required additional surgery. Function remained stable with a mean preoperative and postoperative Snellen visual acuity of 0.09. Conclusions Not anchoring retinotomy edges with a laser at the time of surgery allows inward curling and central slippage of retinal edges under silicone oil. This appears to compensate for the retinal fibrosis occurring in the weeks following surgery and may result in less macula-off re-detachments under oil, and potentially, in better visual outcome

Toxic effect of indocyanine green on retinal pigment epithelium related to osmotic effects of the solvent

PURPOSE: To investigate whether the toxic effect on cultured retinal pigment epithelial (RPE) cells after application of indocyanine green is related to the osmolarity of the solvent or to toxic effects of the dye and evaluate whether these changes also occur using infracyanine green. DESIGN: Experimental study with a direct live/dead cell staining technique using fluorescent dyes. METHODS: Cultured human RPE cells were exposed to various solutions and cell viability was confocally measured. RESULTS: Increased cell death was found in cultures incubated in the hypoosmotic solvent that is generally used for indocyanine green (P <.001, n = 12). Addition of indocyanine green did not alter this observation (P <.001, n = 12). In cultures exposed to a 5% glucose solution, no increased cell death was found (P =.94, n = 12), nor when infracyanine green was added (P =.13, n = 12). CONCLUSION: The observed toxicity of indocyanine green on RPE cells is probably related to the hypo-osmolarity of the solvent and may be avoided by using infracyanine green dissolved in glucose 5%.status: publishe