Objective To evaluate the variability of four parameters of multi-focal electroretinogram (mERG) a-wave amplitude, b-wave amplitude, awave latent period, b-wave latent period. Methods Sixty normal eyes of 46 volunteers were divided into 3 groups of different ages. RETIscan 3-12 system was used to carry out mERG examination. The stimulus matrix of 61 hexagonal elements spanning the central 24deg;of the visual field. These hexons were scaled with eccentricity and divide d into 5 rings. First-order kernel was selected. Results The variability of four parameters of mERG was great. The variability of b-wave latent period was the smallest, its coefficient of variatian was 4.52%～15.62%；that of a-wave latent period held the second place:10.29%~48.67%；that of b-wave amplitude was greater:25.92%~76.11%；that of a-wave amplitude was the greatest:43.82%~88.23%. The results of three groups showed that b-wave amplitude of ring 1 had the smallest variability. Conclusions The variability of latent period is smaller than that of amplitude; the variability of b-wave was smaller than that of a-wave. The longer the centrifugal distance, the lower the amplitude density of a-wave and b-wave. Physiological and anatomical factors might be important for the variability of parameters of multi-focal electroretinogram. (Chin J Ocul Fundus Dis, 2001,17:277-279)
ObjectiveTo observe the pathological changes of central retinal artery occlusion (CRAO) by optical coherence tomography (OCT).MethodsFifty-three eyes of 53 patients who were diagnosed as CRAO in our center between January 2001 to January 2004 underwent the examination by OCT. The intervals between the disease onset and OCT examination were less than 2 weeks. The scan modes of OCT were horizontal or vertical line scan. The locations of scanning were macular, posterior pole of retina, optical papilla and the focus of bleeding or exudation.ResultsThe OCT pathological changes of CRAO in vivo includes increase of retinal thickness and reflex of retina, width of dark layer of photoreceptor (edema), edema or cystoid edema of fovea, retinal bleeding, cotton-wool spot and papilla edema. Four patients who had ciliary retinal artery showed normal retinal structure in the supply region of ciliary retinal artery.ConclusionOCT can display the pathological changes of retinal tissues in CRAO in vivo, especially on the old patients or the patients with systemic disease who were contraindicated by FFA. The unique OCT image of pathological changes of CRAO supply the objective signs for the instant clinical diagnosis.(Chin J Ocul Fundus Dis, 2005,21:74-78)
Objective To investigate the clinical features of polypoidal choroidal vasculopathy. Methods The clinical manifestations and the findings of fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) of 7 eyes in 6 patients with polypoidal choroidal vasculopathy were analyzed retrospec tively.Results The ophthalmoscopic examination of PCV in this series of patients revealed orange-red lesions mainly in macular region in early stage, and then hemorrhage, exudation, edema, serous and (or) hemorrhagic detachment of retinal pigment epithelium in affected portions in advanced stage, and retinal and choroidal atrophy in late stage. FFA discovered the vascular dilation at the border of the choroidal vascular network in 1 eye, dotted hyperfluorescence in 6 eyes, and patches of hyperfluorescence in late phase. ICGA disclosed a vascular branching network in choroid with polypoid pattern of the terminal path of the vessels of network in early phase in 5 eyes, and the typical dotted or clustered polypoidal hyperfluorescence in 7 eyes in late phase.Conclusion The characteristic findings of FFA and ICGA are very diagnostic for PCV. (Chin J Ocul Fundus Dis，2003，19：269-332)
ObjectiveTo observe the characteristics of images of optic coherence tomography (OCT) for the macular region of congenital retinoschisis and investigate its significance.MethodsThe data of OCT of 11 patients (20 eyes) with congenital macular retinoschisis diagnosed by direct or preplacedmirror ophthalmoscopy, fundus fluorescein angiography (FFA), and electroretinography (ERG) were retrospectively analyzed.ResultsThe images of OCT showed split in the mid portion of sensory retina at the macula in all eyes. The retina of fovea centralis was divided by the split into two slightly thickening layers. In addition, in a few number of cases, the parafoveal sensory retina which became much thickening with 2 splits, was divided into 3 layers.ConclusionThe characteristic of images of OCT in macular congenital retinoschisis is the split cavity at the middle layer of the retina, and OCT has a high sensitivity in the diagnosis of congenital retinoschisis. (Chin J Ocul Fundus Dis, 2005,21:93-96)
Objective To compare the characteristics of the ocular fundus of exudative age-related macular degeneration (AMD) with polypoidal choroidal vasculopathy (PCV). Methods The photographs of ocular fundus of 123 patients (137 eyes) with exudative AMD and 42 patients (48 eyes) with PCV diagnosed by fundus photography, fundus fluorescein angiography (FFA), and indocyanine green angiography (ICGA) were retrospectively analyzed. Results In 137 eyes with exudative AMD, 16 eyes (11.7%) had classic neovascularization (CNV), 121 (88.3%) had occult CNV. In the eyes with occult CNV, 42 eyes (34.7%) had hot spots, 74 eyes (61.2%) showed plaque hyperfluorescences and 2 eyes (1.7%) had hot spots with PCV in ICGA. In 48 eyes with PCV, 7 eyes (14.6%) had subretinal reddish-orange lesions, 2 eyes (4.2%) of the polypoidal dilations with branching vascular network were detected with FFA, 36 eyes (75.0%) demonstrated polypoidal dilations with branching vascular network, and 12 eyes (25.0%) showed scattered polypoidal dilations without identifiable continuous branching vascular network, 16 eyes (33.3%) had the polypoidal dilations resembling a cluster of grapes, and 32 eyes (66.3%) showed the polypoidal dilations as several solitary round aneurismal dilations. The polypoidal dilations showed either a washout of the dye from the polyp with staining of its walls or staining of the dye in the late phase of ICGA. Conclusions The different features of exudative AMD and PCV in the ICGA, and the PCV with subretinal reddish-orange lesions are useful in the differentiate diagnosis of the both diseases. (Chin J Ocul Fundus Dis，2004，20：307-309)
Optic coherence tomography (OCT) is one of the most rapid developing technologies in ophthalmology. OCT angiography (OCTA) has been made possible by the development of even faster scanning and sampling techniques, which is the next milestone after stratus OCT and spectral domain OCT. Without the need of injection of the contrast agent, OCTA is capable of providing a three-dimensional reconstruction of the perfused microvasculature within the retina and choroid by detecting the motion of scattering particles such as erythrocytes within sequential OCT cross-sectional scans performed repeatedly at the same location of the eye with different analysis algorithms. Comparing to fundus fluorescein angiography and indocyanine green angiography, with improved OCT technology and understanding, OCTA has showed certain advantages to diagnose retinal and choroidal diseases, especially macular vascular diseases. It is important to establish the contributions that OCTA can make to diagnosing, managing and understanding of ocular fundus diseases.
Objective To measure and compare the difference between the normal control and retinoschisis with multifocal electroretinography. Methods Nineteen cases (21 eyes) of normal control and 8 cases (15 eyes) of inherited retinoschisis were measured with VERIS ScienceTM 4.0.Three cases (6 eyes) of inherited retinoschisis were tested with Ganzfeld ERG. Results There was statistically significant difference of average response density and latencies in all 6 ring retinal regions between the normal control and retinoschisis. The topography of multifocal ERG showed that multifocal amplitude decreased with disappearing or decreasing of central peak amplitude in patients with retinoschisis. The P1/N1ratio of the multifocal ERG average response densities in 6 ring retinal regions was different from the b/a ratio of the Ganzfeld ERG. Conclusion Each of the multifoca l ERG and Ganzfeld ERG has its advantage in the diagnosis of the retinoschisis. (Chin J Ocul Fundus Dis, 2001,17:268-270)