Objectives To investigate the expression of pax-6 in ret ina of in fant monkeys with myopia induced by optical defocus, and to determine the role of pax-6 would play or not in onset and development of myopia and emmetropization.Methods Nine healthy infant rhesus monkeys, aged from 1 to 3 months, were selected and wore spectacle lenses or underwent photorefractive keratectomy (PRK).Transcription polymerase chain reaction method and quantitative analysis were used to determine the expression of pax-6 in the retina with myopia induced by optical defocus in different time, and the result was compared with that in retina without myopia.Results The myopia caused by hyperopic defocus was found. The expression of pax-6 in the retina with myopia induced by optical defocus was significantly higher than that in the retina without myopia（t=3.480，P=0.004）.Conclusions The expression of pax-6 is enhanced by hyperopic defocus in the infant monkey retina, which suggests that pax-6 may be involved in vision-dependent eye growth and emmetropization. (Chin J Ocul Fundus Dis，2003，19：201-268)
Objective To investigate the features of optic disc formation and retinal nerve fiber layer(RNFL) changes in primary open-angle glaucoma with myopia (M-POAG). Methods On 63 eyes of 38 patients with M-POAG were imaged of the fundus,and were evaluated with the microcomputer image analyser,and were compared with the simple POAG (S-POAG) eyes. Results Variant features of the optic disc and RNFL atrophy were found in this M-POAG eyes.The shapes of the optic disc were revealed to be vertically or horizontally oval,obliquely inserted and irregular,the color of the most of optic disc was pallor.The pattern of glaucomatous cupping was saucer-like (28.6%),vertical (25.4%),oblique (23.8%),pot-like (9.5%),and focally or concentrically cupped.The quotient of the neuroretinal rim area and horizontal C/D ratio were significantly lower than those in S-POAG eyes (Plt;0.05,Plt;0.001).The focal point of the optic disc excavtions tended to be inferior.Most of the incidence in the focal atrophy of RNFL was located inferiorly,and the diffuse atrophy of RNFL was correlated positively with middle or late high-myopia POAG eyes (P＜0.005). Conclusion The variant features of the optic discs,glaucomatous cupping and RNFL atrophy formation in M-POAG eyes found in this series might be helpful in clinical diagnosis. (Chin J Ocul Fundus Dis,2000,16:81-84)
Objective To investigate the iconographic characteristics and clinical significances of synchronic examination of indocyanine green angiography (ICGA) and fundus fluorescein angiography (FFA) for high myopia.Methods Thirty patients (57 eyes) with high myopia（gt;-6.00D）, selected randomly and consecutively, were examined by ICGA and FFA synchronically.Results The result of early phase of FFA showed hypofluorescence of the background in 25 eyes，while of late phase showed subretinal neovascularization (SRNV) in 10 eyes and streak formation in 40 eyes. The result of ICGA showed choroidal retrobulbar arteries in 8 eyes, hypofluorescence of the background in 35 eyes, SRNV in 8 eyes, and streak formation in 52 eyes.Conclusion The iconographic characteristics of ICGA and FFA of high myopia include hypofluorescence of the background, SRNV and streak formation. ICGA can givemore exact information on the lesions of choroid in high myopia. The synchronic examination of ICGA and FFA may act as a guide to the therapy for high myopia.(Chin J Ocul Fundus Dis，2003，19：87-89)
Pathological myopia can induce choroidal neovascularization (PM-CNV). The potential risk factors include ageing, long axial length of the eyeball, thinning of subfoveal choroidal thickness, fundus atrophy spot and lacquer crack. These factors may induce atrophy of retinal pigment epithelial cells (RPE) and hypoxia, resulting in vascular endothelial growth factors (VEGF) secretion by outer retina. The lesion type, location and activity of PM-CNV can be determined by fundus fluorescein angiography. The features of PM-CNV on optical coherence tomography include strong reflective area close to RPE with very small amount of subretinal fluid (active stage), surface strong reflection with signal attenuation area (scar stage) and flat lesion and chorioretinal atrophy (atrophy stage). Photodynamic therapy and intravitreal injection of anti-VEGF drugs are major treatments for PM-CNV, the latter is more commonly used now. However, more large randomized controlled studies are required to explore the treatment regimen (such as frequency, indications for repeated or termination of treatment) and the efficacy factors further.
PURPOSE:To examine the role of apoptosis in photoreceptor cells degeneration process in Pathologic myopia. METHODS: Nine human eyes with pathologic myopia were studied by histopathologic and TDT-mediated biotin-dUTP nick-end labelling (TUNEL) techniques. RESULT:The characteristic DNA fragmentation of apoptosis was observed in scattered photoreceptor cells in 4 of 9 eyes. CONCLUSION:The results suggested that apoptosis is one of the pathways of photoreceptor cells death in retinal degeneration of pathologic myopia. （Chin J Ocul Fundus Dis,1996,12: 144-146 ）
Objective To observe the clinical effects of surgical treatment of retinal detachment(RD) caused by macular hole(MH) in high myopia. Methods The clinical materials of 149 eyes of 149 high myopia patients with RD caused by MH were reviewed. The cases were divided into complete posterior vitreous detachment (PVD) group and incomplete PVD group. The anatomic successful rate of operative treatment was evaluated according to the applications of vitrectomy surgery and non-vitrectomy surgery respectively in each group. The visual acuity changes after the operations were also observed.Results The anatomic successful rates were as follow: 77.9% in total cases with vitrectomy surgery and 25.9% with non-vitrectomy surgery (P＜0.001); 75.5% in cases of incomplete PVD with vitrectomy surgery,and 15.0% with non-vitrectomy surgery (P＜0.001); and in non-vitrectomy cases, 57.1 % in complete PVD group and 15.0% in incomplete PVD group (P=0.05). The rates of visual improvement were 68.6% in complete PVD group and 57.0% in incomplete group (P＞0.05). Conclusions The scleral buckling combined with vitrectomy, gas intraocular tamponade and postoperative photocoagulation is an effective and optimal procedure for RD caused by MH in high myopia. (Chin J Ocul Fundus Dis，2003，19：8-10)
ObjectiveTo assess the fundus characteristics and their associations with refractive error, best corrected visual acuity (BCVA) of highly myopic eyes in Chinese teenagers. MethodsThis is a cross-sectional and retrospective study. 544 teenagers (1050 eyes) with refraction more than -6.00 D were recruited from Tongren Eye Care Center. All participants underwent examinations including cycloplegic auto-refractometry and retinoscopy, BCVA, slit lamp and 45℃olor funds photography centered in macular. BCVA was recorded with logarithm of the minimum angle of resolution (logMAR) acuity. 988/1050 (94.1%) fundus photographs with clearly visible optic disc and fovea were selected for analysis. Degree of tessellation in optic disc and macular was defined by the exposure of choroidal vessel. Area of beta parapapillary atrophy (PPA), maximal and minimal diameter of optic disc, degree of fundus tessellation were measured by Image J software. Optic disc ovality was calculated by maximal diameter/minimal diameter. Associations between degree of tessellation, beta PPA area, optic disc ovality and refractive error, BCVA were analyzed. Presence of high myopic retinopathy, including chorioretinal atrophy, lacquer crack and Fuchs spot were also observed. ResultsMean spherical equivalent was (-10.66±2.63) D. Mean logMAR BCVA was 0.11±0.22. Tessellation was in 66.9% eyes. Mean degree in macular and peripapillary region was 0.83±0.96 and 1.04±1.00 (r=0.875, P=0.000). Beta PPA was in 97.3% eyes and mean area was (0.45±0.57) mm2. Mean ovality factor was 1.25±0.18 and Tilted optic disc was in 28.5% eyes. Refractive error, logMAR BCVA, beta PPA area, tilted optic disc and ovality factor were related with the degree of optic disc and macular tessellation (P < 0.05). Highly myopic retinopathy was found in 28 eyes, with older age, larger area of PPA, higher presence of tilted optic disc and degree of tessellation, worse BCVA. ConclusionsBeta PPA was the main fundus characteristics in teenagers. Visual acuity can be seriously impaired by highly myopic retinopathy, such as chorioretinal atrophy.
Dome-shaped macula (DSM) of high myopia has been described as an inward convexity or bulge of the macular within the concavity of the posterior staphyloma in highly myopic eyes, with the bulge height over than 50 μm, which can be observed by optical coherence tomography. There are three patterns of DSM, including the typical round dome, the horizontally oriented oval-shaped dome and the vertically oriented oval-shaped dome. The pathogenesis of DSM development remains unclear, several hypotheses have been suggested, such as localized choroidal thickening in the macular area, relatively localized thickness variation of the sclera under the macula, resistance to deformation of sclera staphyloma, ocular hypotony and tangential vitreoretinal traction. Vision-threatening macular complications of DSM including serous retinal detachment, choroidal neovascularization, foveoschisis and retinal pigment epithelial atrophy. Clinically, asymptomatic patients with DSM mainly take regular follow-up observation. Appears serous retinal detachment and significant visual impairment, treatment with half-dose photodynamic therapy, supplementary of laser photocoagulation or oral spironolactone may have a beneficial effect. However, more large clinical studies are required to confirm the exact efficacy of these treatments.
Objective To evaluate the correlation between retinal thickness (RT) at the macular area and the axial length (AL) in myopia. Mehtods Optical coherence tomography (OCT) was used to detect the RT at the macular fovea, and at the superior, nasal, inferior, and temporal side of the fovea and parafovea area. The AL of the examined eye was measured by IOL master measuring machine, and the correlation between RT at the macular area and the Al was evaluated. Results The minimum RT in the macular area in the eyes with myopia was (150.90plusmn;22.10)mu;m.The retina at the temporal side of parafovea was the thinnest. The average RT in the areas around the fovea was negatively correlated with the AL, and there was no correlation among the minimum RT, the mean RT at the fovea, and the AL of eye. Conclusions As the AL of eye increases, the RT at the parafovea decreases, while the minimum and the average RT at the fovea remain unchanged. (Chin J Ocul Fundus Dis, 2006, 22: 397-399)
Pathological myopic macular retinoschisis can be classified into 4 types based on optical coherence tomography (OCT) images: outer layer retinoschisis, outer + middle layer retinoschisis, outer + inner layer retinoschisis and multilayer retinoschisis. Currently vitrectomy is the major option to treat this condition as it can remove the posterior vitreous cortex completely and peel the internal limiting membrane (ILM) around the posterior vessels arch. Vitrectomy benefits the visual function significantly for outer layer retinoschisis with foveal detachment, but has no or very little effects on multilayer retinoschisis. The appropriate starting site for removal of posterior cortex and ILM should be the site without inner layer retinoschisis. The knowledge and understanding of the OCT classification of pathological myopic macular retinoschisis is important for us to chose correct operation methods and determine the prognosis after treatment.