视知觉学习与全遮盖治疗对于超敏感期弱视患者的功能重建研究

发布时间：2018-02-24 09:48

本文关键词： 弱视空间视功能视锐度对比敏感度全遮盖治疗视知觉学习　出处：《浙江大学》2013年硕士论文　论文类型：学位论文

【摘要】：弱视是一种神经系统发育疾病,眼部无明显器质性病变,主要表现为空间视功能的减退和双眼视功能的受损,通常伴随屈光参差、斜视或形觉剥夺。弱视在人群中的发病率大约是2%-4%,是临床上小儿单眼失明的最常见原因。弱视不仅严重影响患者的学习,生活和工作,还给患者带来了大量的心理压力和经济负担。弱视的认知功能损害及其他治疗方式的探索无疑具有重要的临床指导意义,同时也为准确理解正常认知机制提供重要的参考依据。弱视的主要表现为空间视觉信息的处理异常,如视锐度下降,空间对比敏感度降低,光栅锐度降低,游标锐度阈值提高等。此外有实验研究提示大脑皮层V1区下游的区域也可能受弱视影响,这将导致高级视觉功能的异常,最突出的表现即双眼融合功能及立体视锐度的减弱或缺失。全面的了解弱视患者视觉功能损伤的特征,将有助于了解弱视视觉系统信息处理机制,同时也有利于临床上弱视的快速筛查。目前,对于传统遮盖治疗对超敏感期儿童(大于8岁)及成人弱视效果如何仍存在较大的争议。故而,对于此问题的研究显得非常有意义。视知觉学习是近年来认知科学的研究热点。最近二十年来,越来越多的研究提示视知觉学习可能是弱视治疗的新选择。本系列研究着重探讨弱视的空间视功能缺损特征(实验1),通过采用连续全遮盖法治疗8-14岁屈光参差性弱视儿童,并进行疗效及安全性评价(实验2),并探索基于视知觉学习的Gabor光栅识别任务对于超敏感期弱视患者的视功能影响的研究。 1.基于M-P视觉通道理论分析单眼弱视空间视觉缺损机制。通过采用ETDRS数字视力表和OptecR6500检测111名7～34岁的单眼弱视者弱视眼和非弱视眼的视锐度和对比敏感度函数,通过BCVA和对比敏感度函数衍生得到的对比敏感度函数曲线下面积(AULCSF)、峰值对比敏感度(S max)、 Smax所对应的空间频率(Frmax)以及截止空间频率(CutSF)分析单眼弱视者的空间视觉缺损特点及其与弱视程度的相关性。结果显示视锐度与AULCSF、 CutSF、 Smax、Frmax在弱视者空间视觉评价时呈现趋势一致性。随着弱视程度的加重,弱视眼的整体空间视觉功能逐渐下降,视觉系统的高频端分辨率逐渐减弱和最佳对比度识别能力降低,最适空间频率向低空间频率偏移。在轻度弱视者中,M细胞通道无明显异常,P细胞各亚型的敏感性下降；而中高度弱视者中,M和P细胞通道均受到不同程度的损伤,且以P细胞通道受损为主。 2.连续全遮盖法治疗8-14岁屈光参差性弱视儿童的疗效及安全性评价。主要研究连续全遮盖治疗8-14岁学龄期屈光参差性弱视儿童的有效性及安全性。随访8-14岁的单纯屈光参差弱视儿童43名,采用连续全遮盖治疗3月(遮盖日／非遮盖日为29/1)。运用ETDRS视力表和Optec6500对比敏感度检测仪测量治疗前、治疗1月后及治疗3月后的视锐度和对比敏感度函数,通过视锐度和对比敏感度所衍生的对比敏感度函数曲线下面积(AULCSF)、峰值对比敏感度(Smax)、Smax所对应的空间频率(Frmax)以及截止空间频率(CutSF)进行空间视功能评价。结果显示针对8-14岁的屈光参差性弱视学龄期儿童进行连续全遮盖治疗是可行的,疗效显著并且快速,能够提升弱视眼最佳识别对比度能力和改善视觉高频端分辨率,同时非弱视眼没有出现视功能减退。 3.视知觉学习改善超敏感期弱视患者的视功能研究。采用基于视知觉学习原理的Gabor光栅识别任务训练14名成人弱视患者(平均20.28岁),并通过对比敏感度和视锐度评价训练前后的视功能变化情况。结果显示,弱视眼在约6000trails的Gabor光栅识别任务训练后视力水平平均提高0.12Log单位,同时通过AULCSF评价发现弱视眼的整体空间视功能有明显的提高(t=-4.163,p0.01)。非弱视眼的对比敏感度函数曲线的平均水平有0.2Log单位的提高,我们认为非弱视眼对比敏感度水平的提高可能是由于弱视眼的视知觉学习提升了非弱视眼对于Gabor光栅刺激的识别能力。利用AULCSF分析Gabor光栅识别任务训练前后非弱视眼的整体空间视功能发现,非弱视眼并没有明显的提高。故而,认为基于视知觉学习的Gabor光栅识别任务训练能够在一定程度上提高成人弱视者的视锐度和对比敏感度。
[Abstract]:The amblyopia is a disease of nervous system development , there is no obvious organic lesion in the eye , mainly manifested as the impairment of spatial visual function and the impairment of binocular vision function . The incidence of amblyopia in the population is about 2 % -4 % , which is the most common cause of blindness in children . The amblyopia not only affects the study , life and work of the patient , but also brings a lot of psychological pressure and economic burden to the patient . The main manifestations of amblyopia are the processing of spatial visual information , such as the decrease of visual acuity , the decrease of spatial contrast sensitivity , the decrease of the sharpness of the grating and the increase of the sharpness of the cursor . In addition , it is suggested that the region downstream of the cerebral cortex V1 may also be affected by the amblyopia . In recent 20 years , more and more research suggests that perceptual learning may be a new choice for amblyopia treatment . This series of studies focused on the characteristics of amblyopia ( experiment 1 ) , and treated 8 - 14 year - old anisometropic amblyopia children by continuous full - cover method , and conducted the efficacy and safety evaluation ( experiment 2 ) , and explored the effect of Gabor grating recognition based on visual perception on the visual function of amblyopia patients in hyper - sensitive period . 1 . Based on the M - P visual channel theory , the visual defect mechanism of monocular amblyopia is analyzed . By using ETDRS digital visual acuity chart and OptecR6500 , the visual acuity and contrast sensitivity function of 111 children with monocular amblyopia aged 7 - 34 were detected by BCVA and contrast sensitivity function . 2 . Efficacy and safety evaluation of continuous full - cover treatment for children aged 8 - 14 years with anisometropic amblyopia . The efficacy and safety of continuous full - cover treatment for amblyopia children aged 8 - 14 years were studied . The visual acuity and contrast sensitivity function were evaluated by using ETDRS visual acuity chart and Optec6500 contrast sensitivity detector . The results showed that continuous full - cover treatment was feasible in children aged 8 - 14 years after treatment and after treatment for 3 months . 3 . Visual function of patients with hypersensitive amblyopia treated with visual perception . 14 adult amblyopia patients ( mean 20.28 years ) were trained by Gabor grating recognition task based on the visual perception learning principle , and the visual function changes before and after training were evaluated by contrast sensitivity and visual acuity . The contrast sensitivity function curve of non - amblyopia eyes has an average of 0.2Log units , and we consider that the improvement of the contrast sensitivity level of the non - amblyopia eyes may be due to the visual perception learning of the amblyopia eye to improve the recognition ability of the non - amblyopia eyes to Gabor grating stimulation .

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R777.44

【共引文献】