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)
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)
Based on the pathogenic mechanisms of age-related macular degeneration (AMD), tremendous preclinical and clinical trials have demonstrated that cell transplantation which aim to replace impaired retinal pigment epithelium (RPE) with healthy RPE cells is a promising approach to treat AMD. So far, choices of cell sources mainly are autologous RPE, iris pigment epithelium, fetal RPE, human embryonic stem cell-derived RPE and human induced pluripotent stem cell-derived RPE, and some of them are undergoing clinical researches. Grafting manners in cell-based therapies are various including RPE sheet or RPE-choroid complex transplantation, RPE cell suspension injection, and RPE sheet transplantation with scaffolds. This review is limited to cell-based therapies for RPE that damaged first in the progress of AMD and focus on recent advances in cell sources, transplantation methods, preclinical and clinical trials, and the obstacles that must be overcome.
Objective lt;brgt;To evaluated the effect of transpupillary thermotherapy (TTT) on age-related macular degeneration (AMD). lt;brgt; lt;brgt;Methods lt;brgt;Sixty-two cases (62 eyes) of exudative AMD were managed with TTT. Before treatment, 58 cases underwent fundus fluorescein angiography(FFA),42 cases underwent simultaneous indocyanine green angiography (ICGA), and 56 cases underwent optic coherence tomography (OCT).TTT was delivered using a 810 nm diode laser with variable spot sizes 0.5-3.0 mm and power range 60-40 mW,60 seconds duration. Sixty-two cases were followed up for 1-10 months with 4.8 months average. lt;brgt; lt;brgt;Results lt;brgt;The visual acuities of last visit were compared with those before the treatment. The visual acuity was unchanged in 43 cases (69.3%), improved in 15 cases (24.2%), and declined in 4 cases (6.5%). OCT was re-done in 51 cases and compared with OCT images before TTT treatment. The height of macular edema was unchanged in 29 cases (56.9%), decreased in 18 cases (35.3%), and increased in 4 cases (7.8%). The amelioration of visual acuity was compatible with that of macular configuration in the majority of cases (74.5%). Only in 13 cases (25.5%) the amelioration of visual acuity lagged behind that of macular configuration. The re-treatment was performed in 18 cases (29.1%), probably due to insufficiency of laser power. No side-effect was found. lt;brgt; lt;brgt;Conclusion lt;brgt;TTT makes most of the cases of exudative AMD retaining or improving their visual acuity. The employment is secured. Further exploration is needed in order to obtain the parameters of the laser treatment. (Chin J Ocul Fundus Dis, 2002, 18: 180-183)
Objective To compare the clinical results of photodynamic therapy(PDT) and transpupillary thermotherapy (TTT) for patients with choroidal neovascu larization caused by exudative age-related macular degeneration. Methods Seventy cases (82 eyes) with exudative AMD were divided into PDT and TTT groups. Thirty-five cases (42 eyes) were treated with PDT. Nineteen eyes had occult or predominantly occult CNV. Twenty-three eyes had classic or predominantly classic CNV. Thirty-five cases (40 eyes) were treated with TTT. Twenty-five eyes had occult or predominantly occult CNV. Fifteen eyes had classic or predominantly classic CNV . Visual acuity, FFA, ICGA and OCT were evaluated before and after treatment. All cases were subfoveal or juxtafoveal CNV. The follow-up was 3-6 months. Results Visual acuity in 3 eyes (15.8％) of PDT group and 1 eye (4.0％) in TTT group increased at least 2 lines. The difference was no significant(P=0.1778), FFA showed cessation or reduction of fluorescein leakage from CNV in 15 eyes(78.9％) in PDT group and 13 eyes(52.0％) in TTT group. The difference was not significant (P=0 .0657). Three months after treatment, The visual acuity of 2 eyes(10.5％) in PDT group and 2 eyes (8.0％) in TTT group increased at least 2 lines. The difference was not significant (P=0.7728). FFA showed cessation or reduction of fluorescein leakage from CNV in 8 eyes(42.1％) in PDT group and 21 eyes(84.0％) in TTT group. The difference was significant (P=0.0037). Conclusion For classic CNV, the short-term effect of PDT is better than TTT concerning visual acuity. The effect of PDT is apparently better than TTT in cessation or reduction of fluorescein leakage one month after treatment. But there was no significant difference between PDT and TTT in cessation or reduction of fluorescein leakage three month after treatment. For occult CNV, there is no significant short-term difference between PDT and TTT concerning visual acuity. There was no significant difference between PDT and TTT in cessatin or reduction of fluorescein leakage one month after treatment. But three month after treatment TTT is apparently better than PDT in cessation or reduction of fluorescein leakage. We need more cases and longer follow-up to evaluate these two kinds of treatments in treating exudative age-related macular degeneration.(Chin J Ocul Fundus Dis，2004，20：285-288)
Age-related macular degeneration (AMD) has become one of the leading causes of irreversible blindness worldwide. With the advancement of stem cell technology, tissue engineering and biomaterials, cell-based therapy has been inspiring for many degenerative diseases. For its unique advantages, AMD has become one of the most promising fields for cell-based therapy, which involve retinal pigment epithelium (RPE) cells, induced differentiation of neural retina cells and related cytokine regulations. RPE cells can be derived from human embryonic stem cells (hESC) or Induced pluripotent stem cells (iPS). Recently hESC-derived RPE cells have been applied to patients with dry AMD with initial success in clinical trials. In terms of tissue engineering, studies are focused on factors affecting the long-term survival of transplanted cells, including tissue scaffolds, soluble hybrid materials and scaffold anchoring. This article briefly reviews the RPE differentiation, neural retina differentiation and related cytokines of cell-based therapy and scaffolds, materials, and cell-scaffolds interactions of tissue engineering in AMD treatment.
Objective To investigate the method and the effects of the surgical treatment of massive subretinal hemorrhage and vitreous hemorrhage associated with age-related macular degeneration. Methods A retrospective study of 14 consecutive patients underwent a complete pars plana vitrectomy. Retinotomy was carried out for removing subretinal hemorrhage by using balanced salt solution. Complete air-fluid exchange and gas or silicone oil tamponade were performed in all patients. The follow-up period was within 3～7 months. Results Atrophy of eyeball in 2 eyes (14.3%) postoperatively. Improvement of corrected final visual acuity and anatomical retinal reattachment were achieved in 12 (85.7%) of the 14 eyes postoperatively. Seven days after operation, muddy-sand-hemorrhage in anterior chamber occurred in 4(28.6%)of the eyes and paracenteses of anterior chamber were performed for these eyes. Conclusion Surgical intervention should be applied in the eyes with the massive subretinal hemorrhage associated with age-related macular degeneration in order to avoid the affected eyes becoming atrophic due to the subsequent complication of vitreous hemorrhage, anterior chamber muddy sand hemorrhage,ghost cell-glaucoma or retinal detachment. (Chin J Ocul Fundus Dis,2000,16:217-219)