Microparticles are small vesicles that are released by budding of the plasma membrane during cellular activation and apoptotic cell breakdown. A spectrum of cell types can release microparticles including endothelial cells, platelets, macrophages, lymphocytes and tumor cells. Biological effects of microparticles mainly include procoagulant activity, inhibition of inflammation and cancer progression. The present study shows that vitreous microparticles isolated from proliferative diabetic retinopathy (PDR) stimulated endothelial cell proliferation and increased new vessel formation, promoting the pathological neovascularization in PDR patients. Oxidative stress induces the formation of retina pigment epithelium-derived microparticles carrying membrane complement regulatory proteins, which is associated with drusen formation and age related macular degeneration. Microparticles from lymphocyte (LMP) play an important role in anti-angiogenesis by altering the gene expression pattern of angiogenesis-related factors in macrophages. Besides, LMP are important proapoptotic regulators for retinoblastoma cells through reduction of spleen tyrosine kinase expression and upregulation of the p53-p21 pathway which ultimately activates caspase-3. However, how to apply the microparticles in the prevention and treatment of retinal diseases is a major challenge, because the study of the microparticles in the fundus diseases is still limited. Further studies conducted would certainly enhance the application of microparticles in the fundus diseases.
Objective To investigate the preoperative design and application of the minimum foveolar translocation distance and angle of macular translocation. Methods The fundus fluorescein and indocyanine green an giographies were performed on 53 eyes of 53 patients with classic subfoveal choroidal neovascularization （SCNV）, including 42 with exudative age-related macular degeneration and 11 with high myopic macular degeneration. The actual area of macular SCNV and the minimum foveolar translocation distance and angle were analyzed. Results The actual area of SCNV was 0.39~18.00 mm2 with the mean of (3.08±3.22) mm2. The designed minimum superior translocation distance was 67~2 240μm with the mean of (845.72±425.23) μm；the minimum designed minimum inferior translocation distance was 53~2 430 μm with the mean of (912.17±547.77) μm. The minimum designed superior translocation angle was 1~32°with the mean of (13.23±6.6 8)°；the minimum designed inferior translocation angle was 1~35°with the mean of (14.06±8.46)°. The individual difference of the minimum designed superior and inferior translocation distance was more than 500 μm in 16 eyes （30.19 % ）, and the difference of translocation angle was more than 10°in 11（20.75%）. Conclusion Preoperative design of minimum translocation distance and angle of macular translocation may be helpful to choose the operation program. (Chin J Ocul Fundus Dis，2004，20：75-77)
Objective To study the significance of detection the short-term fluctuation (SF) of macular light threshold detected by Octopus-123 automatic perimeter in suspected early age-related macular dege-neration (AMD). Methods SF of macular light sensitivity, Amsler chart and central visual acuity were examined in 51 patients(66 eyes) with suspected early AMD group and in 32 patients (40 eyes) in the control group. Results SF were significantly different in suspected early AMD group and control group. SF was more sensitive than the examination of central visual acuity and Amsler chart. SF was related to the quantity, location and quality of drusen. Conclusion Visual function of some suspected early AMD patients with drusen may be damaged, though the central visual acuity appears normal. (Chin J Ocul Fundus Dis, 2002, 18: 119-120)
The prevalence of diabetes mellitus in adults of China has reached 12.8%. Diabetic retinopathy (DR) accounts for approximately 1/4-1/3 of the diabetic population. Several millions of people are estimated suffering the advanced stage of DR, including severe non-proliferative DR (NPDR), proliferative DR (PDR) and diabetic macular edema (DME), which seriously threat to the patients’ vision. On the basis of systematic prevention and control of diabetes and its complications, prevention of the moderate and high-risk NPDR from progressing to the advanced stage is the final efforts to avoid diabetic blindness. The implementation of the DR severity scale is helpful to assess the severity, risk factors for its progression, treatment efficacy and prognosis. In the eyes with vision-threatening DR, early application of biotherapy of anti-vascular endothelial growth factor can improve DR with regression of retinal neovascularization, but whether it is possible to induce capillary re-canalization in the non-perfusion area needs more investigation. Laser photocoagulation remains the mainstay treatment for non-center-involved DME and PDR.
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)
Purpose To clarify the relationship between diabetic retinopathy (DR) and maculopathy (DM) and explore the clinical implication of independent graduation of DM. Methods Fundus fluorescein angiography and routine ophthalmological examination were performed on 582 cases of diabetes.Their ocular fundi and macular impairments were graded. Results In general,the severity of diabetic macular impairment was accompanied by retinal involvement,but discrepancy existed between DM and DR.Degree I DM occurred in 5.4% (16/294) among cases without DR,in stage IV DR,degree Ⅲ DM accounted for the most part ,54.5% (116/213).There were still 5.1% (2/39) cases without DM in stage Ⅴ DR. Conclusion The degree of the macular lesions in DM is often not in parallel with the gradation of general affections in retinal tissue other than in macular region in DR,therefore,independentg radation of diabetic maculopathy has its clinical significance for choosing the optimal period of treating maculopathy and preserving the macular function. (Chin J Ocul Fundus Dis,2000,16:153-154)
The authom analysed the predisposing factors for macular pucker(MP) after retinal dotachment surgery.Thirteen clinlcal risk factors correlated with the development of MP were identified, As the incidence related to various factors was compared with reported in the literature,the most significant 3 risk factors of MP were: the obvious hemorrhage accumulated in maeular area, the macular hole treated with diathernly,and the patient lay on one's back for approximately 2 weeks during postoperative retard absorption of subretinal fluid in the eyes with preoperative PVR,This suggested that the direct or indirect damage of maeular area was the major cause of development of MP. （Chin J Ocul Fundus Dis,1993,9:8-10）