One eye each in 3 groups of 12 pigmented rabbits after bilateral vitrectomy received 0.5mg, 1mg or 2mg triamcinolone acetonide (TA), respectively. The fellow eye received only balance saline solution as control. Ophthalmoscopy and electroretinography were performed during 1 day to 38 days after vitrectomy and drug injection. Light and electronmicroscopic studies were done on the 28th day. The particles of drug were visible on day 28 in all TA-treated eyes. Administration of 0. 5rug and 1mg TA did not result in different changes in ERG b-wave amplitudes compared with those in control eyes(P＞0. 05). There were significant elevations of ERG b-wave in 2mg TA eyes compared to the control eyes(Plt;0.05), Both ligbt and electronmicroscopy of the retina in these groups were almost normal. The results showed no Toxielties in TA treated eye up to 2mg after vitrectomy. This offers the experimental evidence as a baseline for combining TA with vitrectomy to reduce recurrence of proliferative vitreoretinopathy. （Chin J Ocul Fundus Dis,1996,12: 105- 107）
ObjectiveTo observe the full-field ERG (ff-ERG) characteristics of patients with acute regional occult outer retinopathy (AZOOR).MethodsA retrospective observational study. From June 2017 to June 2019, 62 eyes of 42 patients (AZOOR group) who were diagnosed with AZOOR in the Department of Ophthalmology of West China Hospital of Sichuan University were included in the study. All patients had no obvious localized disease on the fundus. Among 62 eyes, BCVA of 16 eyes were＜0.1, BCVA of 27 eyes were ≤0.5, and BCVA of 19 eyes were＞0.5. From June 2018 to January 2019, 40 normal volunteers (80 eyes) who attended the outpatient clinic of West China Hospital of Sichuan University and passed detailed ophthalmological examination to exclude all eye diseases including refractive errors were selected as the normal control group. All the examined eyes were tested with ff-ERG using the German Roland visual electrophysiological inspection system. The peak times and amplitudes of the waveforms induced by each response of dark adaptation 0.01 ERG, dark adaptation 3.0 ERG, dark adaptation 3.0 ERG, light adaptation 3.0 ERG, and light adaptation 30 Hz flicker ERG were recorded, respectively. The peak time and amplitude of each ff-ERG response between the two groups were compared by independent sample t test. The peak time and amplitude of each ff-ERG response between different BCVA eyes in the AZOOR group were compared by variance test.ResultsCompared with the normal control group, 0.01 ERG b wave of the dark adaptation of AZOOR group (t=3.601, －6.120), 3.0 ERG a wave and b wave of dark adaptation (t=2.627, －4.263, 3.719, －5.866), 3.0 Oscillation potential P2 wave of dark adaptation (t=－6.625), 3.0 ERG a wave and b wave of bright adaptation (t=3.762, －3.612, 3.648, －3.739) and 30 Hz flicker ERG P wave of bright adaptation (t=－3.832), all peak time of those were significantly delayed, the amplitude decreased, and the difference was statistically significant (P＜0.05). Comparison of different BCVA eyes in the AZOOR group showed that 0.01 ERG b wave amplitude of dark adaptation (F=3.950), 3.0 ERG a peak and b wave amplitude of dark adaptation (F=4.408, 4.876), oscillation potential P2 wave amplitude of dark adaptation (F=4.295), 3.0 ERG b wave amplitude of bright adaptation (F=4.344) and 30 Hz flicker ERG P wave amplitude of bright adaptation (F=4.483) of differences were statistically significant (P＜0.05). There was no statistically significant difference in waveform peak time and amplitude of the other reactions (P＞0.05). Pairwise comparison results showed that, compared with those with 0.1≤BCVA≤0.5 and BCVA＞0.5, those with BCVA＜0.1 dark adaptation to 0.01 ERG b wave, dark adaptation 3.0 ERG b wave, dark adaptation oscillation potential P2 wave, and light adaptation 3.0 ERG b wave and light adaptation 30 Hz scintillation ERG P wave amplitude were significantly reduced, and dark adaptation to 3.0 ERG a peak was significantly delayed, the difference was statistically significant (P＜0.05).ConclusionsThe ff-ERG of patients with AZOOR show delayed peak time and decreased amplitude of each response. The worse BCVA are accompanied by the more obvious decrease of each response amplitude of ff-ERG.
Objective To measure the macular function of the fellow eye in patients with unilateral retinal vein occlusion (RVO). Methods A total of 24 cases of unilateral RVO were diagnosed by fundus fluorescein angiography (FFA), and multifocal ERG (mfERG) was recorded by RETI scan. The mfERG data of 24 fellow eyes of those RVO patients, and 18 normal control eyes were analyzed and compared. The parameters included the amplitude density, latency of the P1 and N1 wave in 6 concentric circles and 4 quadrants of the mfERG graphics. Results The amplitude densities of P1 and N1 wave in first and second concentric circles of RVO fellow eyes were significantly lower than normal eyes (t=4.520, 2.147; P＜0.05). There was no significant difference (P＞0.05) of P1/N1 latency in any concentric circles or quadrants between RVO fellow eyes and normal eyes. Conclusion The central fovea of the RVO fellow eyes was functionally impaired.
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.
Objective To explore the connection between the melanin content of retinal pigment epithelial (RPE) cells and the function of photoreceptors, and the function of melanin on retinal light damage. Methods Agematched old dopachrome tautomerase knockout (DCT-/-) mice and wildtype mice were collected as the DCT-/- group and wildtype group, with 20 mice in each group. Baseline electroretinograms (ERG) in accordance with the international standards for the clinical electrophysiology were performed on all the mice, and the max ERG was recorded. Two mice were randomly selected in each group and were executed，and the removal eyeballs were as the control. The remaining 18 mice in each group were exposed to cold fluorescent light with the quantity of electricity of 20 W for 36 hours with a circle of 12 hours light12 hours dark12 hours light, which was repeated continuously for three times. The light intensity was (5000plusmn;356) lx. Six days after the light illumination, ERG were performed again and the results were recorded. Cervical dislocation methods were used to executed 2 mice which were chosen randomly in each group, and the eyeballs were removed. The tissue sections were observed under the optical and electron microscope.Results The results of ERG showed that the amplitude of a and b wave was lower in DCT-/- group than that in wildtype group before and after light injury （a wave before light injury: t=-7.13，Plt;0.01；b wave before light injury: t=-4.414，Plt;0.01；a wave after light injury: t=-10.162，Plt;0.01；b waveafter light injury: t=-6.772，Plt;0.01）. The decrease of amplitude of a and b wave was much obvious in DCT-/- group than that in wildtype group （a wave:t=4.975,Plt;0.01；b wave:t=2.908,Plt;0.01）. After the light injury, retinal edema and thinning were found in DCT-/- group which wasobvious than that in wildtype group; the photoreceptor layers and melanin were more seriously affected in DCT-/- group than that in wild-type group.Conclusions After the light illumination, the melanin of RPE cells reduces and the function of photoreceptors decreases, which suggests that melanin may play an protective role in the light injury.
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 observe the changes of visual acuity and multifocal electroretinogram （mfERG）before and after pars plana vitrectomy (PPV) combined with internal limiting membrane（ILM）peeling with ICG on idiopathic macular hole surgery. Methods The clinical data of 19 patients (19 eyes) with idiopathic macular hole（IMH） who had undergone PPV combined with ILM peeling assisted by 0.25% ICG from Zhongshan Ophthalmic Center were retrospectively analyzed. The closure of macular holes was confirmed by OCT two months after surgery. VERIS Science 4.9 visual evoked response image system was used to record the amplitude density of P1 waves according to six concentric rings before and two,six,twelve months after surgery, meanwhile compared and analyzed best corrected visual acuity（BCVA）before and after surgery. Results The results of OCT showed that 16 eyes (84.21%) had anatomic closure of the macular hole two months after the surgery while three eyes (15.79%) failed in the closure. The BCVA after surgery improved significantly which was more obvious at the second month (F=6.389，Plt;0.05). Compared with before surgery, the responses were depressed severely in P1 wave amplitude densities in six rings, the differences were statistically significant (t=6.140，Plt;0.05). Conclusion The postoperative BCVA of IMH patients improved but the amplitude densities of P1 wave depressed compared with before surgery.
Objective To observe the mutifocal electroretinogram (mfERG) characteristics of rod and cone cells in patients with retinitis pigmentosa (RP) and to evaluate the function of photosensory cell.Methods The mfERG recording technique for rod cell in eight normal subjects (eight eyes) were established and the influence of different brightness lightstimulus in P1 wave amplitude were analyzed. The cone and rod cells mfERG of 38 eyes in 19 patients were recorded and then calculated positive ratio from local signalnoise ratio. The average visual acuity and P1 wave amplitude density of cone mfERG in different types were compared and statistically analyzed. Meanwhile, the changes in P1 wave amplitude of cone and rod mfERG in four quadrants also compared and analyzed. Results Rod cell mfERG in normal subjects can be recorded stably by using blue flashes with low light intensity as 0.04 cd/m2. In patients with RP, the cone and rod cells mfERG can be detectd 65.79% and 10.51% respectively. P1 wave amplitude density in type I of cone cell mfERG was significantly higher than that in type II (t=5.21,P=0.000). There were no differences in average visual acuity (t=1.15, P=0.612). P1 wave amplitude density in type I was negatively related to logMAR visual acuity （r=-0.48，P=0.04）.The comparison of rod and cone cells mfERG in local wave characteristics showed that P1 wave amplitude densities had spatial relationship in each area. Conclusions The results suggested highly variable central responses in cone cell in RP patients, higher positive recorded ratio in cone cell than rod cell and spatial correspondence between the function of reserved cone and rod cells.
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.
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.