闪光视网膜电图时域、频域联合分析评价慢性高眼压模型大鼠的视网膜功能

Combined analysis method of flash electroretinogram in domains of time and frequency to evaluate retinal functions of chronic ocular hypertension rat models

背景：闪光视网膜电图的单一时域分析方法在慢性高眼压大鼠模型视网膜功能评价的应用中存在局限性。目的：应用闪光视网膜电图时域、频域联合分析方法评价慢性高眼压大鼠模型的视网膜功能。设计、时间及地点：自身对照动物实验,于2009-01/03在首都医科大学动物实验中心完成。材料：选用成年健康、雄性SD大鼠11只。方法：大鼠左眼经定量硅氧烷类油状液体注入前房以诱导慢性高眼压模型,右眼不作处理。分别于术前1d及术后3周2个时间点,顺序记录大鼠左眼视杆反应、最大混合反应、振荡电位、视锥反应以及30Hz闪烁光反应;各波幅值、潜时由罗兰视觉电生理仪测量,通过matlab软件对视网膜电图波形进行频谱分析。主要观察指标：a波、b波、振荡电位及闪烁光反应的幅值、潜时;振荡电位频谱中主频率及其对应振幅值;各特征频率范围内的能量值（以振幅表示）。结果：术后大鼠左眼视杆反应b波幅值显著降低（P〈0.01）;最大混合反应、振荡电位、视锥反应以及30Hz闪烁光反应各波幅值均较术前降低（P〈0.05）;最大混合反应a波潜时较术前延长（P〈0.05）。振荡电位频谱中主频率对应的能量及在60～110Hz、140～170Hz、200～210Hz及230～250Hz频率范围内能量和显著下降（P〈0.05）;大鼠造模前、后在60～300Hz能量总和显著降低（P〈0.01）,但整个频段内能量的变化趋势一致。结论：对大鼠视网膜电图波形采用时域和频域联合分析的方法,可准确、客观地对慢性高眼压模型大鼠的视网膜功能损伤情况进行评价。

BACKGROUND： A single use of the time-domain analysis of flash electroretinogram （F-ERG） has limitation in evaluating the retinal functions on chronic ocular hypertension rat model. OBJECTIVE： To investigate the application of F-ERG in combination with domains of time and frequency in the evaluation of retinal functions in rats. DESIGN, TIME AND SETTING： Self-controlled animal trial was performed at the Animal Experimental Center of Capital Medical University from January to March 2009. MATERIALS： Eleven healthy, male, adult SD rats. METHODS： Chronic glaucoma rat models were made by the injection of an oily liquid of siloxanes into the anterior chamber of left eyes; and the right eyes were not given any treatment. Scotopic and photopic ERGs were recorded sequentially in rats 1 day before and 3 weeks after surgery on experimental eyes. The amplitudes and the implicit times of ERG-waves were measured by Roland electrophysiological system, and the frequency spectrum of oscillatory potentials （OPs） was analysis by matlab software. MAIN OUTCOME MEASURES： The amplitudes and the implicit times of a-waves, b-waves, OPs waves and flick-ERG wave; the main frequency and its corresponding amplitude; the summed amplitude in the frequency range of 60 Hz to 300 Hz of OPs in frequency spectrum. RESULTS： The amplitude of rod-ERG b-wave of left eyes decreased obviously （P 〈 0.01）. The amplitudes of max-ERG, Ops, Cone-ERG and 30-Hz flick-ERG waves decreased as well compared with before surgery （P 〈 0.05）; Max-ERG a-wave had prolonged implicit time compared with before surgery （P 〈 0.05）. The amplitude of main frequency and total amplitude in frequency range of 60 Hz to 110 Hz, 140 Hz to 170 Hz, 200 Hz to 210 Hz, and 230 Hz to 250 Hz decreased （P 〈 0.05） in frequency spectrum of Ops; moreover, the summed amplitude of 60 Hz to 300 Hz reduced sharply （P 〈 0.01 ） but the frequency spectrum curve had the same development trend at the time point of pre-surgery and post-surgery. CONCLUSION： The combined analysis method of F-ERG in domains of time and frequency could provide a series of comprehensive, objective and efficient parameters to evaluate the retinal function in chronic glaucoma rat models.