Atrophic age-related macular degeneration (AMD) does not show obvious loss of visual function in the early stage, so it is not easy to be taken seriously. In the advanced stage, most of the patients suffered from macular area retinal map atrophy, which affected night vision and central vision. Drugs currently used in clinical or clinical trials to treat atrophic AMD include drugs for improving choroidal perfusion, reducing the accumulation of harmful substances, preventing oxidative stress injury, inhibiting inflammatory reactions, as well as neuroprotectants and lipid metabolism drugs. Stem cell transplantation for atrophic AMD is currently the most promising treatment. In theory, it is feasible to replace atrophic AMD with retinal photoreceptor cells and RPE cells derived from human stem cell differentiation. However, there are still many problems to be solved, such as how to improve the efficiency of directional differentiation of seed cells and how to ensure the safe and effective RPE cell transplantation and survival after transplantation. At present, several studies have found that multiple locus mutations are associated with atrophic AMD, so gene therapy also plays an important role in the development of the disease.
Age-related macular degeneration (AMD) is a fundus disease characterized by degeneration of retinal photoreceptor cells, RPE cells and choroidal capillaries. The pathogenesis is not clear and there is no effective treatment. Cell therapies can slow or reverse the vision loss of AMD in animal models, which include implantation of bone marrow mesenchymal stem cells, pluripotent stem cells, RPE cells into the subretinal cavity. Therefore, cell therapy is a promising strategy for the treatment of AMD.
Vascular endothelial growth factor (VEGF), platelet derived growth factor (PDGF) and complements play key roles in the pathogenesis of age-related macular degeneration (AMD). Pegaptanib, the first therapeutic aptamer against VEGF165, has been approved by the Food and Drug Administration (FDA) of US for the treatment of exudative AMD. Another two aptamers E10030 and ARC1905, each target PDGF-B and complement C5 respectively, are undergoing clinical trials. Recent trends to treat AMD are combined therapies targeting multiple key molecules in the pathogenesis of AMD; aptamers against multiple targets may become the preferred drug for AMD.
ObjectiveTo summarize the clinical results and safety of photodynamic therapy (PDT) through 4 years after single and multi-treatments of patients with subfoveal choroidal neovascularization (CNV) caused by age-related macular degeneration(AMD). MethodsClinical data of 73 AMD cases (95 eyes) diagnosed through fluorescein angiography (FFA), indocyanine green angiography (ICGA) and optic coherence tomography (OCT), treated with PDT were reviewed and analyzed in this hospital from June 2000 to June 2004. The changes of best corrected visual acuity (BCVA), fundus pictures, FFA, ICGA and OCT were compared before and after PDT. Follow-up time varied from 3 months to 4 years (mean, 2 years). ResultsThe mean age of 73 patients was 67.8 years old. The BCVA was from CF/10 cm to 1.0. At the final follow up, the BCVA was improved (increase≥2 lines) in 39 eyes (41.1%), stabilized (±1 line) in 51 eyes (53.7 %) and decreased 2 lines in 5 eyes (5.3%). Fundus hemorrhage and exudation reduced after PDT. FFA and ICGA showed CNV complete closure in 58 eyes (61.05%), partial closure in 6 eyes (6.32%), CNV incomplete closure in 22 eyes (23.16% ) and recurrence in 9 eyes (9.47%). After once PDT of 12 eyes with early-stage AMD, the BCVA improved (from 0.6 to 1.5), CNV completely closed, and the OCT showed disappearance of macular edema and neursensory retinal deta chment. No CN V recurred in our four years follow-up observation and the BCVA of the patients remained stable. The mean number of PDT treatment was 1.8 per eye in 95 cases. No serious local or systemic complications were encountered. ConclusionsSingle or multiple sessions of PDT can acheive long-term safety and efficacy. For early-stage AMD patients with minimally classic CNV, PDT can completely make CNV closed and reduce the risk of visual loss.(Chin J Ocul Fundus Dis,2004,20:275-279)
Exudative or wet age-related macular degeneration (AMD) is characterized by the progressive growth of choroidal neovascularization (CNV). Anti-vascular endothelial growth factor (VEGF) drugs have been used in the control of the development of CNV and vision improvement, but there are still defects like frequent injections, drug resistance and so on. Radiotherapy can deactivate local inflammatory cell populations, and make CNV unstable in the absence of pericytes and VEGF stimulation, which induce apoptosis of the vascular endothelial cells. Therefore, radiotherapy is considered as a potential adjuvant treatment of anti-VEGF therapy. The current clinical approaches include epimacular brachytherapy (EMBT) and long-range stereotactic radiotherapy (SRT). SRT may be a preferred adjuvant treatment for patients receiving anti-VEGF therapy. Knowing the progress of radiotherapy for the treatment of exudative AMD may help us to fully understand the pathogenesis of wAMD in China
Purpose To evaluate shortterm visual acuity effects of a single photodynamic therapy(PDT) treatment with Visudyne (CIBA Vision Corp, Duluth, Ga) for choroidal neovascularization (CNV) in age-related macular degeneration (AMD). Methods Definitely diagnostic AMD patients with classic CNV were treated with PDT (5 cases, 7 eyes). The data of visual acuity testing, ophthalmic examination, color photographs, optic coherence tomography, fluorescein angiograms and indocyanine green angiogram before photodynamic therapy and 1 week ,1 month after it were used to evaluate the effects of a single treatment of PDT with Visudyne. Results The visual acuity of all the treated eyes at the follow-up examination at 1 month after PDT were not reduced. Distinct reduction of fluorescein leakage from CNV was noted in all patients by 1 week after PDT. Fluorescein leakage from a portion of the CNV reappeared by 1 month after treatment in 2 eyes. Conclusion PDT with Visudyne achieved short-term cessation of fluorescein leakage from CNV without loss of vision or growth of classic CNV in some patwo ients with AMD. (Chin J Ocul Fundus Dis,2000,16:213-216)