Retinal degeneration mainly include age-related macular degeneration, retinitispigmentosa and Stargardt’s disease. Although its expression is slightly different, its pathogenesis is photoreceptor cells and/or retinal pigment epithelial (RPE) cel1 damage or degeneration. Because of the 1ack of self-repairing and renewal of retinal photoreceptor cells and RPE cells, cell replacement therapy is one of the most effective methods for treating such diseases.The stem cells currently used for the treatment of retinal degeneration include embryonicstem cells (ESC) and various adult stem cells, such as retinal stem cells (RSC), induced pluripotent stem cells (iPSC). and mesenchyma1 stem cells (MSC). Understanding the currentbasic and clinical application progress of ESC, iPSC, RSC, MSC can provide a new idea for the treatment of retinal degeneration.
The retinal vessel changes are the primary and major features of retinal vascular diseases. The retinal vessel is part of systemic vessels with its own characteristics to sustain normal retinal function. These basic characteristics are important to the correct understanding and proper treatment of retinal vascular diseases. Always keep in mind that the retinal vessels is one part of the systemic vascular system, thus retinal vascular diseases may have systemic etiology, and systemic drug administration may have a profound effects to the whole body. However retinal vascular system also has its own structural and functional characteristics, thus retinal vascular diseases are also different from the systemic diseases. Finally the main function of retinal vascular network is to maintain the neuro-retinal function, thus we should balance the vision protection and treatments against abnormal retinal blood vessels. Over-treatments may damage the retinal vision.
Objective To observe the effects of subretinal transplantation of rat mesenchymal stem cells (rMSCs) on Sodium Iodate (SI)induced retinal degeneration. Methods One hundred and twenty BrownNorway (BN) rats were divided into three groups including SI injection group,rMSCs transplantation group and normal control group, each with 40 rats. The retinal degeneration was induced by caudal vein injection of SI. The retinal pigment epithelium（RPE）and neural retinal were evaluated by ocular fundus photograph, fluorescein fundus angiography (FFA)，electroretinogram (ERG) and histological approach, and TUNEL（terminal deoxynucleotidyl transferasemediated dUTP nick end labeling ）. CMDiIprelabeled primary rMSCs were transplanted into the subretinal space of SIinduced rats. The survival, integration, and differentiation of rMSCs were observed between 14 day to 60 day after the transplantation.Results The rat retinal function was gradually reduced after14 days of SI injection, with a timedependent manner. After the RPE cells were damaged，the outer segments of photoreceptors became disrupted and shortened until karyopyknosis. The nuclear morphology and positive TUNEL labeling indicated that the death of photoreceptor cells was apoptosis. After rMSCs transplantation, CMDiI labeled donor cells were observed to be scattered in the subretinal space and expressed RPE cell markers. Average amplitude of b wave and Ops (oscillation potential) in ERG improved 27.80%,59.38% respectively after rMSCs transplantation.Conclusions Transplanted rMSCs can survive in subretinal space and differentiate into RPE.
ObjectiveTo observe the application value and therapeutic efficacy of wide-field digital pediatric retinal imaging system (RetcamⅢ) fundus fluorescein angiograms (FFA) assisted photocoagulation on familial exudative vitreoretinopathy (FEVR). MethodsThe study included 46 eyes of 34 patients with staging 2 FEVR. All patients received color fundus photography and FFA under general anesthesia. The blood vessel reliability of color fundus photography and FFA was comparatively determined. Binocular indirect ophthalmoscope laser photocoagulation was applied to peripheral retina with abnormal leakage as indicated by FFA, the wavelength was 532nm, the duration was 0.25 s and the energy was 200-280 mW. After laser photocoagulation, fundus imaging and FFA was repeated. Further laser photocoagulation was immediately added to areas with vessel leakage but missing the photocoagulation. After treatment, the mean follow-up duration was 14.4 months. The follow up focused on neovascularization, exudative lesions, vitreous traction and merging of photocoagulation spots within 3 months, and on fibrosis membrane resulting in macular traction, tractional retinal detachment, vitreous hemorrhage or Coats disease-like retinal exudates after 3 months. ResultsIt was hard to identify the blood vessels based on the color fundus images and some avascular zone maybe missed. Neovascularization can't be determined by shape of the blood vessels. On the other hand, those new blood vessels can be easily recognized by FFA as leakage sites at the boundary of avascular zone. The surgeon could quickly and accurately locate the FEVR area guided by the color fundus images and FFA from same angle under binocular indirect ophthalmoscope. During the treatment, there was no retinal FEVR area missed laser photocoagulation for all patients. There was no neovascularization, exudative lesions, vitreous traction within 3 months, and no fibrosis membrane, tractional retinal detachment, vitreous hemorrhage or Coats disease-like retinal exudates after 3 months. There were no ocular and systemic complications during and after the FFA and laser photocoagulation. ConclusionWide-field RetcamⅢFFA can help retinal specialists to identify abnormal neovascularization, locate the lesion area, and thus increase the success rate of laser photocoagulation, reduce the ocular and systemic complications for FEVR.
In recent years, with the deepening of understanding of children's retinal diseases and the continuous updating of treatment techniques, the efficacy of children's retinal diseases has also been improved. Due to the particularity of the anatomical structure of the retina of children in the growth and development stage and the pathogenesis, clinical manifestations and outcomes of children's retinal diseases are different from those of adults, the principles of treatment of adult retinal diseases cannot be directly applied to children's retinal diseases. Cryotherapy, laser photocoagulation, intravitreal injection of anti-VEGF drugs, and vitreoretinal surgery are the main treatment methods for children's retinal diseases. However, there are still many problems in the selection of indications, equipment parameters, and treatment of complications. The treatment norms of the disease need to be further improved. Therefore, research on the treatment of children's retinal diseases, and the establishment of surgical standards and norms through expert consensus and other methods are helpful for the treatment of children's retinal diseases.