Macular Degeneration: Du H

Zhang P, Wang Y, Hui Y, Hu D, Wang H, Zhou J, Du H. · Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, PR China. · Ophthalmologica. · Pubmed #17947829 No free full text.

Abstract: BACKGROUND: Vascular endothelial growth factor (VEGF) is upregulated by hypoxia and is a major stimulatory factor for choroidal neovascularization. The upregulation of VEGF expression in response to hypoxia occurs through hypoxia-inducible factor 1 (HIF-1), which is a transcription factor that regulates genes involved in the response to hypoxia. HIF-1 alpha is the inducible subunit of the HIF-1. AIMS: To further define HIF-1 function in angiogenesis and to explore novel approaches to modulate choroidal neovascularization in age-related macular degeneration. METHODS: In this study, we examined the response of human retinal pigment epithelium (RPE) cells to hypoxia and employed the small interference RNA technique to knock down gene expression of HIF-1 alpha in RPE cells. Results: We found that both the mRNA and protein levels of HIF-1 alpha in the RPE cells increased in response to hypoxia, followed by increasing expression of VEGF. Both the mRNA and protein levels of HIF-1 alpha and VEGF in the RPE cells were decreased dramatically after transfection with a HIF-1 alpha-specific small interference RNA vector. CONCLUSION: Our results suggest that HIF-1 may be involved in angiogenesis by controlling the expression of VEGF in vivo and provide a possible strategy for the treatment of angiogenesis by targeting the HIF-1 alpha in ischemic retinopathies.

Zhang CF, Dong FT, Chen YX, Li ZQ, Jia Y, Du H, Han BL. · Department of Ophthalmology, Peking Union Medical College Hospital, Eye Research Center of Chinese Academy of Medical Sciences, Beijing 100730, China. · Zhonghua Yan Ke Za Zhi. · Pubmed #16271171 No free full text.

Abstract: OBJECTIVE: To evaluate the efficacy of transpupillary thermotherapy (TTT) on circumscribed choroidal hemangioma. METHODS: Ten eyes of 10 cases with circumscribed choroidal hemangioma (age 16-48, average 34.4) were included in the present study. Six cases had previous green laser (4 argon and 2 krypton) photocoagulation, TTT as a primary treatment was used for other 4 cases without previous laser application. Fluorescein angiography, visual acuity, anterior segment and fundus examination, perimetry test, FFA/ICGA and ultrasonography were performed in all patients before the treatment. One to five infra red diode laser spots (810 nm with power of 800-1200 mW, diameter of 3 mm) were delivered on the surface of tumor with 60 seconds exposure, additional 10-20 seconds exposure was used in some cases. Second treatment was given 1-3 month later if there was active leakage demonstrated by fluorescein angiography. The followed-up period was 6-36 months (averaged 14.5 month). RESULTS: After transpupillary thermotherapy, 9 eyes (90%) showed partial regression of the tumor. Average visual acuity was 0.25 and 0.6 before and after TTT, respectively. Six patients showed improvement of vision acuity, but vision acuity in 4 patients with cystic macular degeneration remained unchanged. No recurrences were observed within follow-up averaged 14.5 months. Transpupillary thermotherapy did not associate with any significant complications. CONCLUSION: Transpupillary thermotherapy is effective to treat circumscribed hemangioma of choroid either as a primary treatment or supplementary therapy to previous laser photocoagulation.

Zhang CF, Jia Y, Li ZQ, Du H, Han BL. · Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Eye Research Center of Chinese Academy of Medical Sciences, Beijing 100730, China. · Zhonghua Yan Ke Za Zhi. · Pubmed #15733431 No free full text.

Abstract: OBJECTIVE: To evaluate the efficacy of krypton laser photocoagulation for treatment of age-related macular degeneration (AMD) complicated with mainly subfoveal classic choroidal neovascularization (CNV). METHODS: Seventeen eyes of 17 cases, aged 50 - 74 years (averaged 60.8 years) with mainly subfoveal classic choroidal neovascularization were treated with krypton laser at lower power setting. The treatment was completed in one session. Another course of treatment was given 4 weeks later if there was active leakage demonstrated at the CNV area. Visual acuity, anterior segment and fundus examination, perimetry test, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed before and after treatment. The follow-up period was 3.5 years on average (1 - 8 years). RESULTS: There was no immediately decrease of visual acuity after treatment. All treated eyes showed absorption of hemorrhages and/or exudates and diminished leakages. Visual acuity was stable in 8 eyes; improved in 6 eyes (>/= 2 lines), and decreased in 3 eyes (</= 2 lines). The central scotoma showed no significant changes after the treatment. Closure of CNV was confirmed on FFA/ICGA and no recurrence was found in 9 cases during 3 years follow-up. CONCLUSION: Krypton laser photocoagulation at low power setting is an effective treatment for AMD with mainly classic subfoveal choroidal neovascularization.

Zhang CF, Li ZQ, Du H, Han BL. · Eye research center Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 10073, China. · Zhonghua Yan Ke Za Zhi. · Pubmed #12921672 No free full text.

Abstract: OBJECTIVE: To investigate the natural course and the final visual acuity in patients of age-related macular degeneration with choroidal neovascularization. METHODS: Thirty five eyes of 29 patients diagnosed as AMD with occult choroidal neovascularization were studied. The eyes which had laser, radiation therapy or surgical treatment were excluded. Visual acuity, fundus examination, fluorescent angiography (FFA) and perimetry test were performed at the first time visit and 5 years following-up at an interval of 1 to 3 months. The average following-up period of time was 8 years (range from 5 to 16 years) which started in 1985 and ended in 2001. RESULTS: Initial visual acuity 0.1 or less was shown in 10 eyes (28.5%, only hands movement can be seen in 4 of 10 eyes), 23 eyes (65.7%) with visual acuity of 0.1 or less (14 eyes with vision acuity of hands movement) on the last visit. 7 of 35 eyes, the final visual acuity improved more than 2 lines, 12 eyes remained the same and 16 eyes had been lost vision more than two lines. At the baseline examination, 25 eyes had macular hemorrhages and 4 eyes had vitreous hemorrhages. The fundus hemorrhages occurred repeatedly 1 to 4 times in 23 eyes during following-up, the macular hemorrhages was detected in 7 eyes at the last visit. At the initial fundus examination, fibrotic membranes were found in 7 eyes; all 35 eyes had disc form scarring with various size in most recent following-up. CONCLUSION: The natural course of Age-related macular degeneration with choroidal neovascularization is prolonged and the final visual prognosis was poor especially in the cases with recurrent macular hemorrhages.