Purpose
To investigate the relationship between the changes of the thickness of retina in macula and the abnormalities in multifocal electroretinog rams (mERG) in diabetic retinopathy.
Methods
mERG and optical coherence tomography (OCT) examination were performed in 38 patients (60 eyes) with DR (phase Ⅲ～Ⅳ). The data were processed with software SPSS and line relation analysis was done.
Results
The response densities of N1, P1 and N2 in central 5deg; area was significantly negative related to the thickness of neuroretina in macular fovea (correlation efficient -0.252～-0.266，Plt;0.05). The response density of N2 in central 10deg; area was also significantly negative related to the thickness of neuroretina in macular fovea (correlation efficient -0. 332，P=0.01).There was no significant relationship between the latencies of N1 in central 5deg;, 10deg; area and the thickness of macula, whereares the latenc ies of P1 and N2 in central 5deg; were negatively related to the thickness of retinal pigment epithelium in the macular fovea (correlation efficient-0.271～ - 0.322，Plt;0.05).
Conclusion
The changes of the thickness of neuroretina in macula may affect the local retinal function in macula, which may be revealed by the reduction of response densities in mERG in patients with diabetic retinopathy.
(Chin J Ocul Fundus Dis, 2001,17:257-259)
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 clinical features of acute zonal occult outer retinopathy (AZOOR).Methods Eighteen patients (18 eyes) with AZOOR were enrolled in this study. All the patients were examined for corrected visual acuity, fundus examination, visual field and electroretinography (ERG). For part of these patients, fluorescein angiography (FFA), optic coherence tomography (OCT), visual evoked potential (VEP) and multifocal ERG (mf-ERG) were performed. Clinical features were observed. Comparative analysis was performed on the electrophysiological results between affected eyes and fellow eyes. The consistency of OCT, visual field and mf-ERG results was investigated.Results The patients included three males and 15 females. All patients were unilateral involved. 16 eyes (88.9%) were myopia, two eyes (11.1%) were emmetropia. 11 eyes (61.1%) have normal fundus; single yellow-white punctuate lesion or old RPE lesion near macular were found in three eyes (16.7%); depigmented zones in temporal retina were found in four eyes (22.2%). All central visual field results were abnormal, but peripheral visual field results were normal. OCT findings included irregularity, absence or breaks of the photoreceptor inner segment/outer segment (IS/OS) junction. Amplitudes of full-field ERG were reduced in the affected eyes (t=3.516，2.689，3.103，3.517，2.999，3.309；P＜0.05), and implicit times were delayed in most responses except for rod response (t=1.023,P=0.306). Amplitudes of P100 wave of visual evoked potential were reduced statistically (t=2.04,P=0.041), but the differences of implicit times between the affected eyes and the fellow eyes were not statistically significant (t=1.687,P=0.092). Amplitude reduction of multifocal ERG existed in all affected eyes. Coincidence was found between results of OCT and mf-ERG. But abnormal zones found by central visual field did not always coincide with those by mf-ERG. Conclusions The majority of patients who develop AZOOR are young women with myopia. Most patients have normal fundus. Central visual field and electrophysiological examinations are always abnormal. Irregularity, absence or breaks of the photoreceptor IS/OS junction can be proved by OCT.
ObjectiveTo observe the changes of multifocal electroretinogram(mfERG)and central visual field before and after surgery in patients with rhegmatogenous retinal detachment (RRD) involving the macular area.
MethodsThis is a retrospective study. Sixteen patients (16 eyes) with RRD involving the macular area (RRD group) and age-matched normal 20 cases (20 eyes, normal control group) were enrolled in the study. All patients in RRD group underwent scleral buckling surgery. Before surgery and 1, 3, 6 months after surgery, RRD eyes and normal eyes were checked by using mfERG and central visual field examination, and macular reaction wave amplitude density, incubation period and 4° visual field mean sensitivity (MS) were observed. The correlation between amplitude density, incubation period and MS in RRD group and the consistency between mfERG and central visual field examination in normal control group and RRD group were analyzed.
ResultsCompared with the normal control group, in RRD group before surgery the macular reaction wave N1 and P1 amplitude density reduced, the incubation period prolonged, the differences were statistically significant (P < 0.05). Postoperative 1, 3, 6 months, in RRD group macular reaction wave amplitude density improved, the incubation period reduced than before surgery, the differences were statistically significant (P < 0.05). Postoperative 1, 3, 6 months, in RRD group macular reaction wave amplitude density reduced, the incubation period prolonged compared with the normal control group, the differences were statistically significant (P < 0.05). Compared with the normal control group, 4° visual field MS significantly reduced in RRD group before surgery reduced, the differences were statistically significant (t=49.752, P < 0.05). Postoperative 1, 3, 6 months, 4° visual field MS significantly increased compared with the preoperative value, the differences were statistically significant (t=-9.580, -16.533, -19.580; P < 0.05); but were lower than that of the normal control group, the differences were statistically significant (t=-6.286, -7.493, -6.366; P < 0.05). Postoperative 1, 3, 6 months, macular reaction wave amplitude density and MS in RRD group showed positive correlation (P < 0.05), and there was no correlation between incubation period and MS (P > 0.05). mfERG and vision consistency in normal control group and RRD group showed good agreement(K=0.886, P < 0.05).
ConclusionsCompared with normal control eyes, in RRD eyes involving the macula area before and after surgery, macular reaction wave amplitude density reduced, the incubation period prolonged and MS values reduced; compared with the preoperative mfERG and central visual field, macular reaction wave amplitude density improved, the incubation period reduced and MS values increased.
Objective:To observe the effect of beta;estradiol on gluta mate concentration in rabbitsprime; retinae injured by ischemic reperfusion.
Methods:Twenty r abbits ware randomly divided into two groups, the control group and the treatmen t group, with 10 rabbits in each group. Before examined by binocular flash elect roretinography (FERG), retinal ischemic reperfusion (RIR) model was induced in t h e right eyes of all the rabbits by increasing intraocular pressure to 120 mm Hg for 60 minutes; the left eyes were as the control eyes. The rabbits were hypoder mically injected with beta;estradiol (0.1 mg/kg) in treatment group and with phys i ological saline in the control group 2 hours before ischemia. The results of FER G of the right eyes in both of the 2 groups 0, 4, 8, and 24 hours after reperfus ion were record respectively and were compared with the results of FERG before r eperfusion. The retina tissue was collected after the last time of FERG. The con c entration of glutamate was detected by Hitachi L8800 amino acid analyzer.
Results:In the right eyes in both of the 2 groups, the result of F ERG showed a beeli ne just after reperfusion. There was no significant difference of awave amplit u de between the 2 groups (t=1.357, 0.798, 0.835; Pgt;0.05); the b wave amplitudes i n experimental group were much higher than those in the control group (t=4.447, 2.188, 3.106; Plt;0.01). The concentration of glutamate in retina was (0.265plusmn;0.014) g/L in the right eyes and (0.207plusmn;0.013) g/L in the left eyes in the control group, and (0.231plusmn;0.007) g/L in the right eyes and (0.203plusmn;0 .014) g/L in the le ft eyes in the treatment group; the difference between the 2 groups was signific ant (F=50.807, P=0.000). There was statistical difference between righ t and left eyes both in the 2 groups and the significant difference of the right eyes betw een the two groups was also found (P=0.000); there was no statistical diffe rence of the left eyes between the 2 groups (P＝0.505).
Conclusion:beta;-estradiol may prevent the increase of the concentration of glutamate in retina induced by RIR to protect retinal tissue.
ObjectiveTo observe the effect of simulated microgravity on the photopic negative response (PhNR) of full-field flash ERG in adult mice.MethodsIn an experimental study, forty-eight adult male C57BL/6J mice (48 eyes) were randomly divided into model and control groups. Model mice were further divided into three subgroups of 8 each: tail-suspended for 15 days (subgroup A), tail-suspended for 30 days (subgroup B), and tail-suspended for 30 days followed by returning to normal position for 30 days (subgroup C). The three control subgroups were similarly fixed with a harness but kept in the normal position for corresponding periods of 15, 30, and 60 days. The mice were immediately examined using ERG-PhNR, flash VEP, OCT and visually-guided behavior in vivo, and subsequently sacrificed to analyze the retinal histology in vitro. PhNR amplitude was measured from baseline to PhNR trough. N1 peak-time and N1-P1 amplitude of VEP was analyzed. The escape duration was used to quantitatively evaluate the visual function of mice. In addition, inner retinal thickness was analyzed by OCT imaging. Data were compared by the independent sample t-test.ResultsPhNR amplitude in the model subgroup A was obviously lower than the corresponding control subgroup, the difference was statistically significant (t=?3.196, P＜0.01). There was no significant difference in PhNR amplitude between the model subgroup B or C and the corresponding control subgroup (t=?1.976, 0.285; P＞0.05). There was no significant difference in FVEP N1 peak-time or N1-P1 amplitude between any of the three model subgroups and the corresponding control subgroup (P＞0.05). There was no significant difference in OCT-measured inner retinal thickness between any of the three model subgroups and the corresponding control subgroup (t=?0.461, 2.073, ?0.402; P＞0.05). The three model subgroups showed almost normal retinal structure, including the retinal ganglion cell, inner pexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, ellipsoid zone and RPE. There was no significant difference in visually-guided escape time between any of the three model subgroups and the corresponding control subgroup (t=?0.637, ?0.955, 1.297; P＞0.05).ConclusionVia tail-suspension, short-term simulated microgravity can affect the PhNR of flash ERG; however, the change is reversible and does not affect visual function of mice.
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)
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 preliminary clinical application value of the handheld non-mydriatic visual electrophysiological diagnostic system RETeval in screening for diabetic retinopathy (DR).MethodsRetrospective clinical study. Fifty-eight patients with type 2 diabetes mellitus and 16 normal subjects who were admitted to Wuhan General Hospital of the PLA from November 2017 to May 2018 were enrolled in this study. All patients had not received any ophthalmologic treatment. All patients were examined by the default “DR assessment protocol” model of the RETeval device, and the “DR score” were measured by the system. The FFA results were used as the gold standard, and the DR was graded according to the international DR grading standard established in 2002. Patients were divided into vision threatening DR (VTDR) positive group and VTDR (?) group, DR (+) group and DR (?) group. Two independent sample t tests was used to compare the implicit time, amplitude, and pupil area ratio between eyes of different groups. Spearman correlation analysis was used to analyze the relationship between “DR score” and DR severity. The receiver operating characteristic area under the curve (AUC) assesses the sensitivity and specificity of RETeval in detecting DR and VTDR. The threshold of sensitivity and specificity was determined by using the maximum Youden index as a standard.ResultsThe AUC of DR was 0.936, the sensitivity was 81%, the specificity was 92%; the AUC of VTDR was 0.976, the sensitivity was 96% and the specificity was 70%. Compared with DR (?) group, the implicit time of DR (+) group was delayed and the amplitude and pupil area were decreased (t=－13.43, 5.49, 6.09; P=0.000, 0.000, 0.000). Compared with VTDR (?) group, the implicit time of VTDR (+) group was delayed and the amplitude and pupil area were decreased (t=－11.05, 7.46, 5.73; P=0.000, 0.000, 0.000). The “DR score” was significantly correlated with the severity of DR (r=0.89, P＜0.05).ConclusionsThe “DR score” measured by the RETeval instrument has a high degree of specificity and sensitivity in the diagnosis of DR and VTDR. It is highly correlated with the severity of DR.
Objective To observe the changes of photopic negative response (PhNR) of electroretinography (ERG) in patients with retinal vein occlusion (RVO). Methods A total of 30 patients (30 eyes) with retinal vein occlusion (RVO) diagnosed by indirect ophthalmoscopy and fundus fluorescein angiography (FFA) were selected; the unaffected fellow eyes of the patients and another 25 healthy agematched individuals (50 eyes) were cllected as the normal control. All of the patients underwent the examination of visual acuity, visual field, and flashERG (FERG); the normal control ones underwent FERG. In the 30 patients with RVO, there were 14 with central RVO (CRVO) and 16 with branch RVO (BRVO). According to the disease history and results of FFA, the patients were divided into 3 time groups: lt;1 month, 1-3 months, and gt;3 months; according to the types of RVO, the patients were divided into ischemic and nonischemic group. The amplitude of PhNR and other parameters were analysed. The relationship among the amplitude of PhNR and RVO types and time course were analyzed.Results The amplitude of PhNR in the CRVO and BRVO eyes was (28.20plusmn;5.8) and (36.96plusmn;4.71) mu;V, respectively; those in the unaffected fellow and control eyes was (61.25plusmn;3.93) and (59.33plusmn;16.92) mu;V, respectively; the amplitude of PhNR was significantly smaller in the CRVO and BRVO eyes than those in the unaffected fellow or control eyes (F=10.69 and 9.80，P＜0.001; F=9.69 and 9.75，P＜0.001). The amplitude of PhNR in ischemic and nonischemic group in CRVO eyes was (22.77plusmn;15.73) and (36.63plusmn;12.91) mu;V, respectively; the difference between the two groups was significant（t=6.54, Plt;0.01）. The amplitude of PhNR in ischemic and nonischemic group in BRVO eyes was (32.39plusmn;13.22) and (46.73plusmn;10.43) mu;V, respectively; there was no significant difference between the two groups（t=2.12, Plt;0.05）. The amplitude of PhNR was (24.58plusmn;14.60) and (27.94plusmn;15.73) mu;V, respectively, in CRVO and BRVO eyes with lt; 1 month disease course; was (50.39plusmn;13.80) and (58.69plusmn;12.43) mu;V in those with 1-3 months disease course; and was (25.40plusmn;19.94) and (34.48plusmn;16.72) mu;V in those with ＞3 months diseases course. Significant difference was found between the 1-3 months group and ＞3 months group in CRVO eyes（F=4.30，Plt;0.01）. Conclusions The amplitude of PhNRs was significantly smaller in RVO eyes than those in the unaffected fellow or control eyes.The amplitude of PhNR amplitude of ischemic type was smaller than that of nonischemic type. The amplitude of PhNR has descending，ascending，and descending tendency during the disease courses.
