Ring-Shaped Subretinal Fibrinous Exudate in Central Serous Chorioretinopathy

Purpose

To clarify the pathologic changes of the ring-shaped, grayish white subretinal fibrinous exudate in central serous chorioretinopathy (CSC), we examined patients with fluorescein angiography (FA) and optical coherence tomography (OCT).

Methods

Using OCT, we prospectively examined 13 consecutive patients (12 men, one woman) (13 eyes) with acute CSC. The fundi were scanned by OCT through the ring-shaped, grayish white lesion.

Results

FA showed focal dye leakage at the center of the ring-shaped, grayish white subretinal exudates. In the area of the exudates, OCT showed moderately or highly reflective masses bridging the neurosensory retina and the retinal pigment epithelium in all eyes. Because the area of the pellucid core of the ring-shaped exudate showed an optically clear space beneath the neurosensory retina, the subretinal reflective masses were separated on cross-sectional images in all 13 eyes. Pigment epithelium detachment was observed in the area of the grayish white lesion by OCT and FA in 7 of the 13 eyes.

Conclusions

In eyes with a ring-shaped, grayish white exudate in CSC, OCT and FA findings indicate that the pellucid core of the exudate is the route of the exudative fluid from the choroid into the subretinal space. A surrounding grayish white lesion seems to be fibrinous exudate that has accumulated in the subretinal space. Jpn J Ophthalmol 2005;49:516–519 © Japanese Ophthalmological Society 2005     

视网膜假体的研究进展

目前视网膜假体是所有视觉假体中研究最成熟、最广泛的一种,其研究目标是帮助失明患者恢复有用视力,尤其针对因视网膜色素变性和年龄相关性黄斑变性等致视力丧失者.依电刺激部位不同,视网膜假体分为视网膜上假体和视网膜下假体.前者通过玻璃体手术将微电极植入并固定于视网膜上;后者通过巩膜途径或玻璃体途径将微电极置于视网膜神经上皮层和视网膜色素上皮层之间.近年来对视网膜上假体的阵列电极、刺激电流等进行了改进;对视网膜下假体的芯片、供能方式等做了改进.有望为不可逆盲者提供帮助.     

Review of the Ocular Angiogenesis Animal Models

Increasing interest in developing reliable and reproducible models to study angiogenesis has emerged due to recent advances in the treatment of eye disease with pathologic angiogenesis. This review provides a summary of the principal ocular animal models for angiogenesis. Models of anterior segment neovascularization include the corneal micropocket assay, used to study the influence of specific molecules/proteins in angiogenesis, and corneal chemical and suture induced injury, which mimic more closely the complex nature of the human disease. Angiogenesis models of the posterior segment include the well-known laser-induced injury of the choroid/Bruch's membrane, as well as the oxygen induced retinopathy and models of injections of pro-angiogenic/inflammatory molecules. In addition, knockout or knock-in transgenic mice provide powerful tools in studying the role of specific proteins in angiogenesis.     

Development of a protocol for maintaining viability while shipping organoid‐derived retinal tissue

Retinal organoid technology enables generation of an inexhaustible supply of three‐dimensional retinal tissue from human pluripotent stem cells (hPSCs) for regenerative medicine applications. The high similarity of organoid‐derived retinal tissue and transplantable human fetal retina provides an opportunity for evaluating and modeling retinal tissue replacement strategies in relevant animal models in the effort to develop a functional retinal patch to restore vision in patients with profound blindness caused by retinal degeneration. Because of the complexity of this very promising approach requiring specialized stem cell and grafting techniques, the tasks of retinal tissue derivation and transplantation are frequently split between geographically distant teams. Delivery of delicate and perishable neural tissue such as retina to the surgical sites requires a reliable shipping protocol and also controlled temperature conditions with damage‐reporting mechanisms in place to prevent transplantation of tissue damaged in transit into expensive animal models. We have developed a robust overnight tissue shipping protocol providing reliable temperature control, live monitoring of the shipment conditions and physical location of the package, and damage reporting at the time of delivery. This allows for shipping of viable (transplantation‐competent) hPSC‐derived retinal tissue over large distances, thus enabling stem cell and surgical teams from different parts of the country to work together and maximize successful engraftment of organoid‐derived retinal tissue. Although this protocol was developed for preclinical in vivo studies in animal models, it is potentially translatable for clinical transplantation in the future and will contribute to developing clinical protocols for restoring vision in patients with retinal degeneration.     

Culture-Proven Candida Albicans Endogenous Endophthalmitis in a Patient with Onychomycosis

ABSTRACT

Purpose: To report a case of Candida albicans endogenous endophthalmitis in an immunocompetent patient with onychomycosis.

Methods: Retrospective case report.

Results: A 40-year-old man with onychomycosis presented with C. albicans subretinal abscess in the left eye. Systemic and intravitreal injections did not prevent further progression of the infection. The patient underwent pars plana vitrectomy. One month after surgery, the intraocular inflammation gradually subsided. However, his visual acuity stayed at counting fingers as a result of macular scarring.

Conclusion: The aim of this case presentation is to emphasize that endogenous fungal endophthalmitis can be seen in an immunocompetent patient. The use of systemic steroids in the past was the main reason for the progression of the disease in this case. In these situations, when the clinical findings suggest a fungal etiology, it should keep in mind that endogenous candida endophthalmitis can be a result of fungal infections from distant sites such as the toenails and systemic steroids should not be started before definite diagnosis.     

Subretinal delivery of erythropoietin alleviates the N-methyl-N-nitrosourea-induced photoreceptor degeneration and visual functional impairments: an in vivo and ex vivo study

Retinitis pigmentosa (RP) is a heterogeneous group hereditary retinal disease that is characterized by photoreceptor degeneration. The present study sought to explore the therapeutic effects of erythropoietin (EPO) on the N-methyl-N-nitrosourea (MNU)-induced photoreceptor degeneration. The MNU-administered mouse or normal control received a subretinal injection of EPO (at the dose of 10U). Twenty-four hours after EPO injection, the retinal EPO levels of experimental animals were quantified. Subsequently, the experimental animals were subjected to optokinetic tests, ERG examination, SD-OCT examination, histology assessment, and immunohistochemistry evaluation. The retinal superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and expression levels of several apoptotic factors were also quantified. The subretinal injection of EPO up-regulated the retinal EPO level in the retinas of MNU-administered mice. The optokinetic tests and ERG examination suggested the visual functional impairments in MNU-administered mice were ameliorated after EPO treatment. The SD-OCT and histological examination suggested the morphological devastations in MNU-administered mice were alleviated after EPO treatment. The cone photoreceptors in MNU-administered mice were protected from the MNU-induced detrimental effects. Moreover, the EPO treatment rectified the apoptotic abnormalities in MNU-administered mice, and enhanced the expression level of Foxo3, a critical mediator of autophagy. The EPO treatment also mitigated the MDA concentration and enhanced the retinal SOD activity, thereby counteracting the retinal oxidative stress in MNU administered mice. In ophthalmological practice, the subretinal delivery of EPO is a feasible therapeutic strategy to alleviate photoreceptor degeneration. These findings would enrich our pharmacological knowledge about EPO and shed light on the development of an effective therapy against RP.