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find Keyword "Electroretinograph" 48 results
  • EFFECTS OF TRIAMCINOLONE ACETONIDE ON ELECTRORETINOGRAM AND RETINAL ULTRASTRUCTURES IN VITRECTOMIZED EYES OF RABBITS

    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)

    Release date:2016-09-02 06:21 Export PDF Favorites Scan
  • Manifestations of acute regional occult outer retinopathy in full-field electroretinogram

    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.

    Release date:2020-12-18 07:08 Export PDF Favorites Scan
  • Effect of β-estradiol on glutamate concentration in retina injured by ischemic reperfusion

    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 L8800 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 awave 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.

    Release date:2016-09-02 05:48 Export PDF Favorites Scan
  • Effect of background light intensity on the slow components and the oscillatory potentials of the electroretinogram

    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)

    Release date:2016-09-02 06:03 Export PDF Favorites Scan
  • Multifocal electroretinogram of rod and cone cells in patients with retinitis pigmentosa

    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 signalnoise 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.

    Release date:2016-09-02 05:43 Export PDF Favorites Scan
  • Acute zonal occult outer retinopathy

    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.

    Release date:2019-05-17 04:15 Export PDF Favorites Scan
  • Preliminary report of the effects of intervention with tanakan on retinal function in diabetic retinopathy after retinal photocoagulation

    Objective To investigate the early effects of intervention with tanakan on retinal function in diabetic retinopathy(DR) after laser photocoagulation. Methods Prospective random controlled study was performed on 60 Patients (60 eyes) from 23 to 69 years old with DR(phase Ⅲ~Ⅳ). The multifocal electroretinograms (MERG) were tested with VERIS Ⅳ before, the 3rd day and the 7th day after photocoagulation. Results No significant differences were found in the latencies and response densities of N1,P1 and N2 between the two groups before photocoagulation. Compared with that before photocoagulation, three days after photocoagulation the latencies in tanakan group had no significant change. The response densities of N1,P1 and N2 reduced and the changes were much smaller than that in control. Three days after photocoagulation, the response densities of P1 and N2 in the central macula 5°area were much higher and the latencies of P1 and N2 were significantly shorter than that in control group. There were no significant differences in the response densities in the 7th day and the differences in the latencies between two groups still existed. Conclusion Tanakan may be effective in preventing the retina from damage of retinal photocoagulation in some degree in DR.  (Chin J Ocul Fundus Dis, 2002, 18: 208-211)

    Release date:2016-09-02 06:01 Export PDF Favorites Scan
  • The applied value of electroretinogram in typing of branch retinal vein occlusion

    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)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • The importance of clinical application of fullfield electroretinography in ophthalmology

    Fullfield electroretinalgraphy (ffERG) is an indispensablemeans in assessment of retinal disease; it is invasive, effective, objective, quantifiable, and reproducible. Currently ffERG has been extensively applied domestically, but it also has disadvantages such as too few detected diseases, nonstandardised methodology, and inaccurate description of the results. It is important to place more emphasis on the internationalization, standardisation, and normalization of the application; obtaining the differences of indication, detection techiniques, and description of the results among ffERG, multifocal ERG and pattern ERG; expanding the new fields and methods of clinical applications. So that ffERG could play an more important role in the diagnosis and management for the patients with retinal disease.

    Release date:2016-09-02 05:43 Export PDF Favorites Scan
  • The multifocal electroretinography in age-related macular degeneration

    Purpose To measure and compare the difference of multifocal electroretinogram in normal subjects and patients with age-related macular degeneration. Methods Seventeen cases(20 eyes)of normal subjects,7 cases(10 eyes)of dry form AMD(age-related macular degeneration),8 cases(8 eyes)of wet-form AMD and 11 cases(11 eyes)of idiopathic macular hole(IMH)were tested with VERIS SciencesTM 4.0 made by EDI company of America.The latencies and average response densities of 6 ring retinal regions in normal subjects were compared with those in various types of age-related maculopathies. Results The N1 and P1 wave latencies of all 6 rings in wet-form AMD and the N1 wave latencies of 3~6 rings in dry-form AMD were delayed statistically.The N1 and P1 wave average response densities of 1~4 rings in and the P1 wave average response densities of 1-6 rings wet-form AMD and the N 1 wave average response densities of 1~5 and the P1 wave average response densties of 1-6 rings in dry-form AMD were decreased statistically.The N1 and P1 wave average response densities of 1~2 and the P1 wave average esponse densities of 1~3 rings were decrease statistically in IMH. Conclusion Multifocal electroretinogram can be used to quantitate the visual function of the affected location in age-related macular degeneration. (Chin J Ocul Fundus Dis,2000,16:224-226)

    Release date:2016-09-02 06:05 Export PDF Favorites Scan
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