次声作用对小鼠视觉电生理学的影响

目的 探讨次声暴露对小鼠视觉电生理学的影响。方法 150只昆明种成年雄性小鼠按次声的不同参数随机分为5大组，每组30只，每大组小鼠按暴露时间随机分为6小组，每组5只，分别暴露于8Hz、90dB，8Hz、130dB，16Hz、90dB，16Hz、130dB的次声压力舱中，每天暴露2h，分另1在暴露0、1、4、7、14、21d后进行视网膜电图(KRG)、闪光视诱发电位(FVEP)、振荡电位(OPs)的检测。结果 8Hz、90dB，16Hz、90dB实验组视觉电生理指标改变较为相似，仅在一些时间点发生改变。8Hz、130dB实验组大部分视觉电生理指标在第7天实验后就明显改变，并随着暴露时间的增加而加重。16Hz、130dB实验组大部分视觉电生理指标在第1天即明显改变，此后增加暴露时间视觉电生理指标有所恢复。结论 次声对小鼠视觉电生理功能的影响与次声的强度和频率有关。不同参数次声对小鼠视觉功能影响程度不同，可能是由于不同频率的次声与视网膜自身频率接近或符合的程度不同，使视网膜不同种类细胞受损程度不一，产生不同的电位变化。     

玻璃体切割术前闪光视网膜电图与术后视力的关系

目的:探讨玻璃体切割术前F-ERG与术后视力的关系.方法:对50例行玻璃体切割手术的患者进行术前F-ERG的测定,术后2周对其视力进行测定, 利用SPSS软件包进行统计学处理.结果:术前F-ERG的a波振幅与术后视力呈正相关;术前F-ERG的b波振幅与术后视力呈正相关;E值(E=La+Lb/Aa+Ab) 与术后视力呈负相关;E小于等于3.0者与E大于3.0组术后视力差异有显著性(P<0.005).结论:玻璃体切割术前进行正确的F-ERG分析,有助于玻璃体切割术后视力的预测.     

OCT及mfERG在DR早期及非增殖期中的应用

目的：用光学相干断层扫描（optical coherence tomo-graphy,OCT）测定糖尿病视网膜病变早期（non-diabetes retinopathy,NDR）及非增殖期（non-proliferative diabetes retinopathy,NPDR）的视网膜形态学改变及用多焦视网膜电图（multifocal electroretinogram,mfERG）测定其视网膜电活动的改变,评价不同分期糖尿病视网膜病变（diabetic retinopathy,DR）的严重程度。 方法：选取50~70岁的老年人30例30眼作为正常组,已确诊为2型糖尿病患者50例50眼做为实验组。分别在标准状态下行OCT及mfERG检查,并对结果进行统计学分析。 结果：对于NPDR的患者,视网膜形态的变化：视网膜黄斑区大部分神经上皮层变厚,说明对于糖尿病这个危险因素,视网膜的功能在不断的下降,视网膜黄斑区神经上皮层在NDR中变化并不明显而在NPDR明显变厚,说明黄斑区形态在糖尿病早期变化并不大,随着糖尿病的病情加重,形态发生了很大变化。电生理学改变：mfERG的P1波随着病情的加重,其反应密度逐渐下降,在NDR就明显减低,而在NPDR,下降更为明显,说明在黄斑区,视网膜形态改变前,电活动已经减弱,在形态发生变化后,电活动的下降更为明显。 结论：OCT联合mfERG测定黄斑区域的形态改变及电活动改变,两种检查手段在疾病的早期观察、随访和进一步治疗的选择上具有很高的应用价值。     

多焦视网膜电流图用于近视眼视网膜功能的研究

目的应用多焦视网膜电流图(mltifocal electroretinogram,mERG)探讨不同程度近视眼不同部位视网膜的功能状态,并与正常人作比较,评价其差异。方法收集我院眼科门诊就诊的18～32岁的病例68例(101眼),分为中低度近视组(23例40眼)、高度近视组(24例40眼)和正常对照组(21例21眼)。所有病例均应用德国罗兰公司的mERG仪记录各环N1波、P1波的潜伏期和振幅密度,再比较3组各检查结果之间的差别。结果 3组N1波和P1波的振幅密度在第1环最大,随离心度的增加而逐渐降低;潜伏期在第1环最小,随离心度增加而逐渐延长。经统计学处理,高度近视组N1波和P1波各环的振幅密度较正常对照组及中低度近视组低,差异均有统计学意义(均为P<0.05);中低度近视组与正常对照组N1波和P1波各环的振幅密度比较,差异均无统计学意义(均为P>0.05)。高度近视组N1波P1波第1环潜伏期较正常对照组及中低度近视组延长,差异有统计学意义(P<0.05),其余组间比较差异均无统计学意义(P>0.05)。结论高度近视眼mERG各环振幅密度较正常眼下降,1环潜伏期较正常眼延长;中低度近视眼与正常眼振幅密度及潜伏期无明显变化。     

NPDR患者黄斑区视网膜厚度、视网膜神经纤维层厚度与全视野闪光ERG的变化

目的探讨非增生性糖尿病视网膜病变(non-proliferative diabetic retinopathy,NPDR)患者黄斑区视网膜厚度(retinal thickness,RT)、视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度与全视野闪光视网膜电图(electroretinogram,ERG)的变化及相互关系。方法选择2010年2月至12月于我院就诊的2型糖尿病患者91例(168眼),依据糖尿病视网膜病变(diabetic retinopathy,DR)国际分期标准分为3组:无糖尿病视网膜病变(NDR)组39例(78眼),轻度NPDR组28例(52眼),中重度NPDR组24例(38眼)。另选择同龄正常人30例(60眼)作为正常对照组。通过光学相干断层扫描检测黄斑区中心RT及RN-FL厚度,全视野闪光ERG检测视网膜功能。结果 NDR组、轻度NPDR组、中重度NPDR组患者黄斑区RT分别为(198.01±22.51)μm、(218.00±28.15)μm、(239.90±65.04)μm,均较正常对照组(184.45±18.50)μm增厚,差异均有统计学意义(t=2.312、5.235、7.947,均为P<0.05);随着DR加重,糖尿病各组间黄斑区RT比较,差异均有显著统计学意义(t=3.305、6.300、3.069,均为P<0.01)。正常对照组与NDR组黄斑区RNFL厚度比较,差异无统计学意义(P>0.05);轻度NDPR组及中重度NPDR组与正常对照组相比,黄斑区RNFL厚度变薄,差异均有统计学意义(均为P<0.05)。与正常对照组比较,中重度NPDR组全视野闪光ERG暗适应0.01反应及明适应3.0反应b波潜伏期明显延长(均为P<0.05),暗适应0.01反应b波振幅和暗适应3.0反应a波振幅均下降(均为P<0.05)。结论随着NPDR病情加重,2型糖尿病患者黄斑区中心RT增加,RNFL厚度减小,视网膜功能受损。     

Longitudinal measures in children receiving ENCAD for hereditary retinal degeneration

A hydrolysate of yeast RNA (ENCAD) is used in the Soviet Union for the treatment of hereditary retinal degenerations. We report longitudinal data from three young patients who have made at least two visits to the Soviet Union over a five-year period to receive treatment with ENCAD. Two children were diagnosed with cone-rod degeneration and the third has an isolated (simplex) form of retinitis pigmentosa. Visual function measurements were obtained before and after each visit to Moscow. In the comparison of previsit and postvisit visual acuity, 30 Hz flicker amplitude, and visual fields, ENCAD treatment had no significant short-term effect. Despite treatment with ENCAD, each patient has shown a significant decrease in visual function over the 5-year period. The rate of progression in these patients appears similar to previously published data on the natural history of their retinal degenerative disorders.Abbreviations ENCAD a hydrolysate of yeast RNA - RP retinitis pigmentosa     

Minimum procedures for visual electrodiagnostic testing

A set of procedures for the electroretinogram, electrooculogram, and pattern and luminance visual evoked cortical potentials was defined by representatives from all Dutch University Eye Clinics in order to promote standardization of procedures for routine diagnostic testing.The procedures have been selected to obtain an answer to most electrodiagnostic questions of frequent occurrence with a minimum of equipment and examination time. An individual examiner may add other procedures to the proposed program to extend and diagnostic possibilities.     

The effects of age on steady-state pattern electroretinograms and visual evoked potentials

Steady-state pattern-reversal electroretinograms and visual evoked potentials were simultaneously recorded in two groups of young and elderly normal volunteers. The young group consisted of 23 subjects (13 women and 10 men) aged 18 to 28 years, and the elderly group consisted of 24 subjects (11 women and 13 men) aged 58 to 77 years. Stimuli were square-wave gratings ranging in spatial frequency from 0.5 to 6 c/deg and phase reversed at a frequency of 4 Hz. Pattern-reversal electroretinograms and visual evoked potentials consisted of a prominent second and a smaller fourth harmonic response. Spatial frequency-amplitude functions of the pattern-reversal electroretinogram second and fourth harmonics were similar for the young and elderly groups. The mean fourth harmonic phase was significantly shifted in elderly subjects compared with young subjects for all spatial frequencies tested. Spatial frequency tuning was observed for amplitude and phase functions of the visual evoked potential second and fourth harmonic responses for both age groups. Age had a significant effect on phase for spatial frequencies above 1.5 c/deg. Amplitude of the fourth harmonic was significantly lower for the elderly group at 1.5–4 c/deg. Phase was significantly different between groups for spatial frequencies below 3 c/deg. Our results suggest that aging influences both retinal and central visual pathways. Aging differentially affected the visual evoked potential second and fourth harmonic responses, suggesting different neuronal origins for these components.     

Goldmann-Favre syndrome in a four-year-old-girl

We report a suspected early stage of Goldmann-Favre syndrome in a four-year-old girl complaining of poor visual acuity in both eyesOphthalmological examinations were performed including fundus examination, fluorescein angiography, and electrophysiological studies. However, dark adaptation and visual field testing were not performed because of her age.Ophthalmoscopic examinations revealed peripheral retinoschisis in the superior temporal retina, diffusely abnormal retinal pigment epithelium, and lack of macular and foveal reflexes in both eyes. Foveal retinoschisis was not observed and the vitreous did not show severe degeneration. Fluorescein angiography showed many leaking points posterior to the retinoschisis. Scotopic electroretinogram (ERG) was almost non-recordable. Photopic electroretinogram showed a marked reduction of the b-wave with a negative shape and delayed peak time. Flash visual evoked potentials were within normal range.It is very difficult to distinguish this case from X-linked juvenile retinoschisis by ophthalmological findings. However, Goldmann-Favre syndrome is most suspected from the fact that the patient is female and her parents and brothers are normal.     

低温对眼电生理的影响

正常有色兔30只,分为37℃、0℃、-5℃三组,经封闭式玻璃体切除术后,采用三种不同温度灌注1小时。于术前及术后1周、2周、1月分别作各眼明暗适应,不同强度闪光视网膜电图(ERG),所得a、b波振幅数据输入电子计算机进行差异性分析,显示-5℃在术后1周ERG的a波振幅与术前有显著性差异。提示过低温度会损害视网膜功能,在眼低温玻璃体手术中不宜采用。