ObjectiveTo study the prevalence of age-related macular degeneration (AMD) in the population aged 50 and over in Qidong County of Jangsu Province. Methods3644 individuals from 4 villages were randomly selected by clustering sampling method, according to the household registration information and door to door visits. Visual acuity was measured by modified Bailey-Lovie E logMAR chart. The examination of eyelids, cornea, lens and fundus were also carried out. The diagnosis of AMD was made according to the clinical hierarchy system by Age-Related Eye Diseases Study. χ2 test was used to analyze the prevalence of AMD and its related factors. ResultsAmong 3644 selected individuals, 2985 individuals received examination with a participating rate of 81.92%. In total 97 patients (136 eyes) had AMD with a prevalence rate of 3.25%. Among them, 71 patients (105 eyes) had early stage of AMD (2.38%); 26 patients (31 eyes) had late stage of AMD (0.87%). In these late stage patients, there were 9 patients (13 eyes) of exudative lesions (0.30%). There were 32 male (3.11%) and 65 female (3.32%) patients. There was no statistically significant difference between male and female prevalence (χ2=0.29, P > 0.05). Correlation analysis results showed that the long-term smoking (χ2=15.19) and heart cerebrovascular disease (χ2=81.50) was associated with AMD (P < 0.05). ConclusionsThe prevalence rate of AMD is 3.25% in the residents aged 50 and above in the rural area of Qidong County, Jangsu Province. Long-term smoking, high blood pressure and cardiovascular disease are the risk factors of AMD.
Objective To observe the optical coherence tomography (OCT) features of Best vitelliform macular dystrophy (BVMD) at different stages.Methods Twenty-eight BVMD patients (56 eyes) were enrolled in this study. All the patients were examined for visual acuity, slit-lamp microscopy, direct ophthalmoscope, fundus photography, electrooculogram, fundus fluorescein angiography (FFA) and OCT. Fifty-six eyes were classified into stage 0 (eight eyes)、Ⅰ (two eyes)、Ⅱ(10 eyes)、Ⅱa （12 eyes）、Ⅲ (six eyes) 、Ⅳa (six eyes)、Ⅳb (five eyes) and Ⅳc (seven eyes) accordingly. The OCT features of BVMD at different stages were observed.Results The OCT results showed that the macular area was normal in eyes of stage 0; disturbance of retinal pigment epithelium (RPE) and subretinal hyporeflective area were found in eyes of stage I; the location of the yellowish material between RPE and the inner segment and outer segment (IS/OS) with normal appearance in RPE and IS/OS interface were found in eyes of stage Ⅱ. In all the other progressing stages from Ⅱa、Ⅲ and Ⅳ, the vitelliform material appeared as a thicker highly reflective lesion located between the outer nuclear layer and RPE layer, usually accompanied by optical hyporeflective lesion. Images of stage Ⅳc were in similar appearance besides edema of retina. OCT images of Ⅳb stage were demonstrated atrophy of retinal layer and IS/OS loss with fibrosis. Conclusions OCT demonstrated the location of the yellowish material between RPE and IS/OS. Optical hyporeflective lesion between the outer nuclear layer and RPE layer accompanied thicker highly reflected lesion might be the characteristic image in stages II a to IV of BVMD.