Objective To observe the effects of clopidogrel and aspirin on hemorrhelogy and platelet aggregation in patients with acute cerebral infarction. Methods 62 patients suffering from acute cerebral infaction were divided into two groups,32 cases were treated with clopidogrel and aspirin, 30 cases were treated with aspirin as control. The observing time was 14 days.GMP140, blood hemorrheology and ADP induced platelet aggregation were measured in all patients before and after treatment. Results After clopidogrel and aspirin treatment, the blood viscosity , ADP induced platelet aggregated rate were remarkably decreased. There was a statistical significance between two groups ( P

Objective To investigate the degree of retinal development in preterm infants. Methods Flash electroretinography (ERG) was performed on 25 healthy preterm infants and 25 full-term ones, and the response of rod cells and cone cells and maximal mixed responses were recorded. The delitescence and amplitudes of a- and b-waves and the ratio of amplitudes of b-/a-wave of maximal responses were analyzed. Results Compared with the full-term infants, The delitescence of responses of rod cells in preterm infants was statistically longer (.t=11.007,P.=0.000) but without any significant changes of amplitudes (.t=1.836,P.=0.069); statistically longer delitescence (.t=2.44, P=0.010; (t=10.800,)P.=0.000) and lower amplitude (.t=5.804,P=0.000; t=5.809,P.=0.000) of a- and b-wave of maximal response were found in preterm infants group. In the response of cone cells, there were significant differences of the delitescence (.t=4.444,P.=0.000) and amplitude (.t=3.819,P.=0.000)of a-wave and delitescence of b-wave(.t=2.850,P.=0.005) between the two groups, and no statistical difference of amplitude of b-wave (.t=0.486,P.=0.628) between the two groups. The ratio of amplitudes of b-/a-wave of the maximal mixed response was not significantly different between the two groups ((.t=1.142,)P.=0.256). Conclusions The development of retinal function is slower in preterm infants than that in full-term ones.

ObjectiveTo analyze the symmetry of multifocal visual evoked potential (mfVEP) between both eyes in normal subjects. Methods The monocular mfVEP of both eyes in thirty-six normal subjects (72 eyes) was tested with VERIS Science 4.0. The stimulus was the pattern reversal dart array consisted of 60 sectors each included 16 black-white reverse patterns. The visual stimulation was controlled by the binary pseudo-random m-sequences and subtended approximately 25 degrees. Results There existed no statistically significant difference of P1 latencies and amplitudes between correspondent quadrant visual field of both eyes. The data difference of the ipsilateral quadrant visual fields was greater than those of the correspondent quadrant visual field. The comparison among four quadrant visual fields in right eye or left eye each showed that there was statistically significant difference of P1 latencies between the superionasal quadrant visual field and inferiotemporal or inferionasal quadrant visual fields. Conclusions The symmetry of normal mfVEP is more dominant in retina than that in visual cortex.

Objective To investigate the characteristics of multifocal visual evoked potential (mf-VEP) in healthy individuals, and provide normal reference values for its clinical application. Methods The mf-VEP of 37 healthy individuals (70 eyes) were examined by VERIS Science TM 4.0. The visual stimulus was a dart board with patterns consisted of 60 patches spanning a 25? visual field. The length of m-sequence was 2 14-1. The results were recorded by bipolar occipital straddle. The signal was amplified 100 K and was put through a band-pass filter between 3 and 100 Hz. The first slice of the second order kernel was analyzed by VERIS software. The summed responses of fields with different stimulus were analyzed and compared according to different ages, genders and eyes. Results The latencies and response densities of amplitude had statistically significant differences both in dimidiate and quartered field(P 0.05). Conclusions The mf-VEP of healthy individuals can reflect the VEP at different field locations objectively with its specific physiological characteristics, which may provide normal reference values for its clinical application.

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 Sciences TM 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 N 1 and P 1 wave latencies of all 6 rings in wet form AMD and the N 1 wave latencies of 3～6 rings in dry form AMD were delayed statistically.The N 1 and P 1 wave average response densities of 1～4 rings in and the P 1 wave average response densities of 1～6 rings wet form AMD and the N 1 wave average response densities of 1～5 and the P 1 wave average response densties of 1～6 rings in dry form AMD were decreased statistically.The N 1 and P 1 wave average response densities of 1～2 and the P 1wave average response 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.

Purpose To observe the features of multi-focal electroretinogram (mERG) in Stargardt′s disease, and evaluate the validity of mERG on diagnosis of this disease. Methods mERG had been recorded in 7 cases (14 eyes) of Stargardt′s disease with VERIS 4.0,and the findings were compared with normal individuals. Results The mERG were remarkably abnormal in all cases of the disease, as the amplitudes of N 1 and P 1 waves were seriously decreased and the latencies were prolonged in all the 6 regions ( P

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 Science TM 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 P 1/N 1 ratio 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 multifocal ERG and Ganzfeld ERG has its advantage in the diagnosis of the retinoschisis.

Objective To investigate the influence of experimental scotoma on multifocal visual evoked potential (mf-VEP). Methods The mf-VEP of 10 healthy individuals (20 eyes) was measured with VERIS Science 4.0. Every eye was measured for 3 times. The right eye was measured with full field stimulation and upper hemi-field or lower hemi-field masked. The left eye was measured with full field stimulation and central three-rings area or lower nasal field masked. The first slice responses of the second order in different field were analyzed and compared by VERIS software. Results The mf-VEP in masked area was undetectable or obviously decreased in all subjects. In most unmasked field, the amplitudes of mf-VEP were not changed, except that in some place decreased slightly with statistically significant difference in comparison to the full field stimulation mode. Conclusion mf-VEP is influenced with experimental scotoma. The mf-VEP changes are consistent with the visual field masked.

Background Behcet's disease is a refractory panuveitis with high blindness rate.Multifocal electroretinography (mfERG) is a useful tool for the evaluation of the function of the posterior retina.ObjectiveThe aim of this study is to assess the characteristics of Behcet's disease using the mfERG.Methods mfERG was recorded in 68 eyes of 39 cases with active stage of Behcet's disease.All of the patients were diagnosed based on the Standard of International Study Group for Behcet's Disease and assigned to the cystoid macular edema (CME) group and the diffuse macular edema (DME) group after assessment by fundus fluorescein angiography (FFA).Seventeen normal subjects were used as controls.Oral informed consent was obtained from all of the subjects prior to this trial.mfERG recording followed the ISCEV Guidelines for Clinical Multifocal Electroretinography (2007 edition).The response density and latency of P1 and N1 waves in 6 rings were analyzed and compared.Results The amplitudes of N_1 waves from rings 1 through 6 and N1 wave from rings 1 through 5 were significantly declined in patients with Behcet's disease compared with normal control (P＜0.01).All of the latencies of P_1 waves from rings 1 through 6 were insignificantly shortened in patients with Behcet's disease compared with normal control (P＞0.05).The amplitudes of P_1 and N_1 waves from rings 1 through 6 in diffuse macular edema group were considerably lower than those in the cystoid macular edema group (P＜0.05,P＜0.01).A test of visual acuity showed a negative correlation to the amplitude and latency of N_1 wave (r=-0.36,-0.37,P＜0.05 ) and a positive correlation with the amplitude of N1 wave (r=0.43,P＜0.05) in the DME group.In the CME group,a test of visual acuity presented a negative correlation to the amplitude and latency of N1 wave and latency of P1 (r=-0.41,-0.35,-0.40,P＜0.05 ) and a positive correlation with the amplitude of P1 wave (r=0.48,P＜0.05).Conclusion mfEGR demonstrates that retinal electro-activity is abnormal in eyes with Behcet's disease.The distinct functional disorder is situated around the fovea.

OBJECTIVETo study the effect of radiotherapy of nasopharyngeal carcinoma on visual evoked potential (VEP).

METHODSVEP of 63 patients with nasopharyngeal carcinoma were tested before, at the end of, half a year, one year, 2 years and 3 years after their radiotherapy.

RESULTSWithin the male group, one year after radiotherapy, the latency of VEP was significantly delayed than that before and at the end of radiotherapy, while the amplitude was decreased significantly. Two years after radiotherapy, the latency of VEP was significantly delayed more than that before radiotherapy. However there was no significant difference among VEP at the end of, half a year and 3 years after radiotherapy. Within the female group, 2 years after radiotherapy, the latency of VEP was significantly delayed than that before radiotherapy. Three years after radiotherapy, the latency of VEP was significantly delayed than that before, at the end of, half a year and one year after radiotherapy. There was no significant difference in VEP amplitudes before and after radiotherapy.

CONCLUSIONWithin the male group, the abnormal delay of VEP latency mostly happens one or two years after radiotherapy. Within the female group, the significant delay of VEP latency happens at the end of radiotherapy and lasts for 3 years, while the VEP amplitude does not change significantly during the 3 years after radiotherapy. The result indicates that the sustained radiation damage within the female visual nerve system starts at the end of radiotherapy, but to a lesser degree. It was shown that radiotherapy of nasopharyngeal carcinoma certainly damages the visual nerve system, though there is sex difference in the impairment.

Adult ; Evoked Potentials, Visual ; radiation effects ; Female ; Humans ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; radiotherapy ; Sex Factors ; Time Factors