ObjectiveTo investigate the neural mechanisms of subjects with anisometropic amblyopia using event-related potential (ERP) technology.MethodsNineteen subjects diagnosed with anisometropic amblyopia were consecutively recruited from the outpatients of the West China Hospital of Sichuan University from June 2013 to February 2014, and twenty normal subjects were recruited as control subjects. All subjects were given different orientation Gabor stimuli with three spatial frequencies (1, 2, 8 cpd) and their ERP was recorded. The differences of P3b, including amplitude and latency, were compared between amblyopic eye and fellow or control eye.ResultsAmong the three groups of amblyopic eye and fellow or control eye, there was no statistically significant difference in accuracy or response time at three spatial frequencies (P>0.05), in latency or amplitude of P3b at low spatial frequencies (1, 2 cpd) ((P>0.05), or in amplitude of P3b at high spatial frequency (8 cpd) (P>0.05). P3b latency of amblyopic eye extended at high spatial frequency (8 cpd), compared to fellow or control eye. Amblyopic eye was most significantly weakened in Brodmann area 17 at the P3b wave of each spatial frequency (1, 2, 8 cpd), and there was most significantly weakened in high spatial frequency (8 cpd).ConclusionThe P3b latency of amblyopic eye extended at high spatial frequency suggests that the cognitive function of amblyopia is impaired, at an extent, in the late visual processing stage.
Purpose To identify the expression of alternatively spliced mRNA isoforms of the NMDA-R1 in the visual cortex of strabismic cats. Methods Two pai rs of normal and strabismic cats were used.The amblyopic cats had been made monocularly esotropic (by tenotomy) at the age of weeks,resulting in behavioral am blyopia.Animals were sacrificed about 6 months by intraperitoneal administration of Nembutal.Cryostat sections of fresh,frozen central visual cortex of the ats were cut to 20 micron thickness.A series of digoxygenin-labelled oligonucle otide probes basing on the human gene sequence were used for ISH.Control probes included sense oligonucleotides and short segment probes which were adjacent to ,but did not,span the splice junctions.A computer-assisted systematic morphometric ounting procedure was used to enumerate hybridising cells. Results The number of positive cells expressing NMDA-R1 mRNA in t he strabismic amblyopic cats was decreased,notably in layer IV of visual cortex (P<0.0001).The pattern of isoform expression varied between normal and strabismic amblyopic cats with decreased numbers of 1-a,1- b and 1-1 isoforms and apparently increased expression of 1-3 P <0.0001),whereas no significant difference was found for the 1-2 and 1-4 isoforms (P>0.05). Conclusion Transcriptional inhibition of NMDA-R1 mRNA and of specifie isoforms may underlie the change in receptor expression.Alternatively,preferentialloss of neurones bearing particular NMDA-R1 isoforms and compensation with a proportional increase in cells expressing other isoforms may occurr during the critical period of visual plasticity. (Chin J Ocul Fundus Dis,2000,16:71-138)
Objective To investigate the characteristic of the multifocal visual evoked potentials(MVEP)and the visual function across the visual field in anisometropic amblyopes and isometropic amblyopes. Methods MVEP from 32 anisometropic amblyopic eyes and 31 control eyes were tested. Results In anisometropic amblyopic eyes,the latencies of MVEP were significantly prolonged.The amplitudes of MVEP were significantly attenuated in the central region of the visual field,and these phenomena gradually reduced with the increase of the eccentricity. Conclusion The visual function of anisometropic amblyopic eyes is reduced more significantly in the central region than in the peripheral region of the visual field. (Chin J Ocul Fundus Dis,20000,16:27-29)
【摘要】 目的 观察综合疗法治疗大龄儿童弱视的疗效。 方法 回顾分析2008年1月-2010年10月在我院初诊并经综合治疗的8~13岁弱视儿童62例85只眼的临床资料。治疗前最佳矫正视力0.1~0.7,平均0.46±0.17。观察患者经弱视综合治疗后视力、空间对比敏感度及立体视提升效果。 结果 治疗后视力正常22例31只眼(36.5%),进步29例39只眼(45.9%),无效11例15只眼(17.6%);总有效率82.4%,与治疗前相比,差异有统计学意义(Plt;0.001)。空间对比敏感度基本正常11例16只眼(18.8%),进步43例58只眼(68.2%),无效8例11只眼(12.9%)。弱视眼在1.5、3、6三个低空间频率的对比敏感度值与治疗前相比提升有统计学意义(Plt;0.001);在12和18两个高空间频率,对比敏感度值与治疗前相比提升无统计学意义(Pgt;0.05)。立体视锐度正常12例(19.4%),进步26例(41.9%),无效24例(38.7%),立体视锐度与治疗前相比提升具有统计学意义(Plt;0.001)。 结论 综合疗法治疗大龄儿童弱视能取得令人较为满意的疗效,患儿视力显著提升,低到中等频率空间对比敏感度及立体视锐度也有较大提升。【Abstract】 Objective To explore the therapeutic effect of comprehensive therapy on elder children with amblyopia. Methods The clinical data of 62 patients (85 eyes) with amblyopia who underwent the comprehensive therapy between January 2008 and October 2010 were retrospectively analyzed. The best-corrected visual acuity was 0.1-0.7 (mean 0.46±0.17) before the treatment. The visual acuity, spatial contrast sensitivity and stereoacuity of the patients after the treatment were observed. Results After the comprehensive therapy, the visual acuity was normal in 22 patients (31 eyes, 36.5%), improved in 29 patients (39 eyes, 45.9%), invalid in 11 patients (15 eyes, 17.6%). The total effective rate was 82.4% which was differed significantly from that before the treatment (Plt;0.001). The spatial contrast sensitivity was almost normal in 11 patients (16 eyes, 18.8%), improved in 43 patients (58 eyes, 68.2%), and invalid in 8 patients (11 eyes, 12.9%). The examination of spatial contrast sensitivity showed that the improvement was only statistically significant when frequency equates 1.5, 3, or 6 (Plt;0.001) compared with those before the treatment; while no statistically significant improvement was observed in higher frequencies of 12, 18 (Pgt;0.05). The stereoacuity was normal in 12 patients (19.4%), improved in 26 (41.9%), and invalid in 24 (38.7%); the difference in stereoacuity before and after the treatment was significant (Plt;0.001). Conclusion The therapeutic effect of comprehensive therapy is good: the visual acuity of the patients improves obviously, and the low to middle spatial contrast sensitivity and stereoacuity improve apparently.
目的:分析探讨单眼散光弱视患儿对比敏感度(CS)视功能的受损特点。方法:对正常儿童组36例、单眼散光弱视组34例、单眼非散光弱视组33例,共103例,用静态F.A.C.T图表和计算机Gabor斑CS检查程序分别检查患儿对侧眼、弱视眼及90°和180°两主子午线方向上的对比敏感度。结果:①单眼散光弱视组和单眼非散光弱视组的对侧眼、弱视眼的CS值在所有空间频率均较正常组的CS降低(Plt;0.05),表现为中、高空间频率区CS的明显受损(Plt;0.01)。②单眼散光弱视组的弱视眼在90°和180°两主子午线方向上的对比敏感度有显著差异(Plt;0.01)。结论:弱视儿童的对侧眼不正常。用计算机Gabor斑检查可以了解弱视散光儿童不同子午线上的CS存在的差异,明确定位弱子午线,并可以针对子午线性弱视,进一步开展知觉学习的治疗。