Objective To explore the clinical application value of multifocal oscillatory potentials (MOPs) in retinal vein occlusion (RVO). Methods MOPs were tested using VERIS 4.0 visual evoked response imaging system for 19 cases (19 eyes) of RVO，among them 8 cases of central retinal vein occlusion (CRVO) and 11 cases of branch retinal vein occlusion (BRVO). Twenty normal subjects were as normal control group. The stimulative visual angles subtended ±26.6°horizontally and ±22.1°vertically. The filter setting was bandpass 100～1000 Hz. The retinal responses from 103 hexagons were recorded in 4 min (8 segments). Results In normal control group, OP-1, OP-2 and OP-3 were recorded during 37 ms for first order and 47 ms for second order first slice in whole test field and 5 ring retinal regions, the oscillatory wave shapes of second order were clearer than those of first order. In RVO groups, 91.6% latencies of OP-1, OP-2 and OP-3 were delayed, and 70.8% amplitudes of OP-1, OP-2 and OP-3 were reduced. The delay of the latencies and the decrease of the amplitude in CRVO were more markedly than those in BRVO. Conclusion MOPs can be effectively and quantitatively used to evaluate the retinal function of the different location in RVO. (Chin J Ocul Fundus Dis,2002,18:20-22)
Objective To icompare the effects of indocyanine green angiography(ICGA) on ganzfeld Electroretinogram(ERG). Methods ICGA was performed used the Topcon 50IA retina camera, Ganzfeld ERG was recorded by Neuropack Ⅱ evoked response recorder. The Ganzfeld ERG was recorded before and after ICGA in 20 cases (38 e yes) with different diseases , Ganzfeld ERG was recorded according to the ISCEV standard recommendations. Results ICGA did neither affect Ganzfeld ERG a-wave and b-wave latency nor amplitudes of dark adaptation, maximum response and light adaptation.(Pgt;0.05). Conclusion ICGA using the Topcon 50IA could be performed prior to the recording of the Ganzfeld ERG. (Chin J Ocul Fundus Dis, 2001,17:284-285)
Objective To investigate the early influences of laser photocoagulation on retinal function in diabetic retinopathy(DR)． Methods The multifocal electroretinograms (MERG) of 30 eyes with DR (phase Ⅲ～Ⅳ) were tested with visual evoked response image system IV b efore,and the 3rd day and the 7th day after laser photocoagulation． Results Three days after photocoagulation, the latency of N1 prolonged in the central macula 5deg; area and superionasal quadrant．Th e response densities of N1,P1 and N2 markedly reduced, and most significant changes occurred in the central macula 5deg; area and then in the central 10deg;area． There were also differences in the changes of the amplitude of N1 and P1 in diff erent quadrants ．The changes of visual acuity were positively related to the de crease of amplitudes of N1,P1 and N2 in the macula． Conclusion The reduction of response densities in MERG reveals functional damage in diabetic retina occurring early after photocoagulation．The functional damage in macula induced indirectly by photocoagulation may explain the reduction of visual acuity after panretinal photocoagulation in some degree． (Chin J Ocul Fundus Dis, 2001,17:181-183)
Objective To explore the effect of ischemia-reperfusion injury on the retinal functions of rats. Methods Seventy Wistar rats were selected, 20 of which were selected randomly and divided into two groups (control group and single-irrigated group). The rats were anesthetized and their anterior chambers of the right eyes were cannulated with a 7-gauge needle connected to a reservoir containing ringers balanced salt solution, which was maintained at the same level o f the eye for 1 hour. After that, ERG was recorded in both eyes of all rats. All the left rats were divided randomly into 10 groups and they were treated as the single-irrigated group. Retinal ischemia was induced by raising the reservoir to a height of 150 mm Hg. One hour later except the single ischemia group, all o f t he groups resumed perfusion after 3,6,12,and 24 hours and 3,5,7,14,and 21 days s eparately. ERG was recorded in both eyes of all rats.Results There was no difference in the results of ERG between left and right eyes in either the control group or the single-irrigated group. All the waves of ERG vanished in the single-ischemia group after 1 hour. In the ischemia-reperfusion groups, the waves of ERG partly recovered and the amplitude reduced persistently and progressively.Conclusion Ischemia-reperfusion injury may affect the function of the retina persistently and progressively. (Chin J Ocul Fundus Dis，2003，19：201-268)
Acute zonal occult outer retinopathy (AZOOR) is an acquired retinal diseases. The majority of patients who develop AZOOR are women characterized by an acute onset of visual blurred and scotoma with photopsias. The fundus examination is often normal or appeared mild abnormal. The RPE atrophy of fundus is similar with white syndrome. Although FFA and ICGA features are either unremarkable or unrelated to AZOOR, there are still important in differential diagnosis. The characteristic abnormalities appearance of FAF (complicated and varied), OCT (regional anomaly of ellipsoid zone), visual field (visual field defect) and ERG (decreased amplitude and prolonged latency of rod reaction, maximum reaction, cone reaction and scintillation reaction) are considered critical examinations to the diagnosis of AZOOR. Although there is no effective therapy for AZOOR, it has some self-limitation.
Objective To probe the possibility of electroretinogram(ERG)maximum combined response for typing branch retinal vein occlusion(BRVO). Methods BRVO were divided into ischemic or nonischemic type according to the appearance of fundus fluorescein angiography.The ERG data were used to define the retinl function:a，b-wave amplitude and impact time,b/a-wave ratio,oscillatory potential OP1，OP2，OP3，OP4 amplitude implicit time and Ops amplitude. Results The ERG b-wave and OPs amplitude were significantly lower in ischemic group than those in nonischemic group. Conclusion With the REG test,the decline of b-wave and OPs amplitude of the maximum combined response might be as a reference of ischemic type BRVO. (Chin J Ocul Fundus Dis,1998,14:10-11)
Objective To observe the changes of electroretino gram(ERG) in temporary traumatic ocular hypotension and to detect the possiblem echanism. Method The rabbit model with ocular hypotenstion was made. At the 2nd, 4th, 8th, 16th week after trauma, the ocular tension and ERG was examined. Result Amplitude of b wave in treated group was 2.5 times as high as that in the control at the 2nd week after trauma, and then decrease to 1.5 times as high as that in the control at the 16th week. Conclution Higher amplitude of b-wave of ERG in rabbit with ocular hypotension may be related to blood circulation congestion, which might lead to accumulation of the metabolic toxin. (Chin J Ocul Fundus Dis，2004，20：189-191)
Objective To study the response of the retinal neuronal adaptive system to changes of background illumination (BG) by measuring the oscillatory potentials (OPs) and the a- and b-waves of the electroretinogram (ERG) in different BG illuminations. Methods The a- and b-wave and the digitally filtered OPs were simultaneously recorded from Wistar Fu rats aged from 25 to 29 days during dark adaptation (DA) and during 6~8 minutes of BG illuminations at four levels increased successively by steps of two log units, i.e., ldquo;low scotopicrdquo; level of 1.43times;10-6cd/m2, ldquo;high scotopicrdquo; of 1.43times;10-4cd/m2 , ldquo;low mesopicrdquo; of 1.43times;10-2cd/m2 and ldquo;high mesopicrdquo; of 1.43times;10-2cd/m2. Full field stimulus flashes of 75 msec duration and 1.43times;10-2cd/m2intensity was delivered at an interval of 1 minute. Results Five OP wavelets were recorded in DA and during scotopic BG illuminations. The number of wavelets was reduced to three as the eyes were exposed to mesopic BG levels. However, the sum of OPs amplitudes (SOPs) increased as the BG was intensified, except at ldquo;high mesopicrdquo; level, by which a significant decrease of SOPs occurred. The amplitudes of the a-and b-waves remained unchanged at the two scotopic BG and decreased as the BG intensity increased to mesopic levels. Conclusion The response of retinal neural adaptive system of the Albino rat to changes of BG light is more sensitive and robust than the slow components of the ERG. The enhancement of the oscillatory responses at ldquo;low mesopicrdquo; illumination level suggests that using proper BG light may be conducive to reducing the variation of OPs. (Chin J Ocul Fundus Dis, 2001,17:286-288)
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)