微视野计下黄斑疾病低视力康复训练研究进展

黄斑疾病随着中心暗点发展，可引起中心视力丧失、阅读速度及固视稳定性下降。目前，退行性黄斑疾病的预防和治疗仍无令人满意的效果，多项研究证实生物反馈治疗对视觉康复的有效性。微视野计利用黄斑疾病患者对中心暗点的大脑皮质可塑性和神经感觉适应可提高视功能，并为更新、更易管理的视觉辅助治疗奠定基础。本文从微视野计对黄斑疾病中心暗点的研究、视觉皮质可塑性、微视野计下低视力康复训练机制及临床研究几个方面进行综述。     

黄斑区脉络膜新生血管患眼光动力疗法治疗前后黄斑结构和功能的光相干断层扫描联合微视野检查

光动力疗法(PDT)是治疗脉络膜新生血管(CNV)安全、有效的方法之一[1].光相干断层扫描(OCT)可以对PDT治疗前后CNV大小、视网膜厚度等形态结构变化进行观察.中心视力虽可以反映黄斑视功能,但CNV导致中心暗点的产生,使中心视力及基于中心视力的检查不能真实地反映黄斑视功能变化.微视野计可以对低视力及固视不良的黄斑疾病患者进行视野定量检测,在黄斑疾病的诊断及随访中正受到越来越多的关注[2].     

复方樟柳碱治疗脉络膜视网膜病变临床观察

目的 探讨复方樟柳碱注射液治疗中心性浆液性脉络膜视网膜病变的临床效果.方法 将136例中心性浆液性脉络膜视网膜病(简称中浆)患者随机分组对照治疗.治疗组69例69只眼,用复方樟柳碱注射液2ml在患侧颞浅动脉旁皮下注射,每日1次,15d为1疗程,连续用药2疗程.对照组67例67只眼,口服复方丹参片0.3g×3片、芦丁片20mg×2片、烟酸片0.1 g×2片,每日3次,连续服药30d.用药前常规检查视力、眼底和视野.结果 两组用药后1月分别复查视力、眼底、视野有明显差异.治疗组69例视力提高5行以上者56例(81%);眼底黄斑水肿消失,渗出吸收,中心凹反光恢复55例(79.7%);视野中心或旁中心暗点消失44例(81%).对照组67例视力提高5行以上者21例(31%);眼底黄斑水肿消失,渗出吸收,中心凹反光恢复19例(28.4%);视野中心暗点或旁中心暗点消失15例(29%).结论 复方樟柳碱治疗中浆疗效显著,安全可靠,具有临床推广应用的价值.     

中心性渗出性脉络膜视网膜病变中心外视力患者光相干断层扫描检查

中心性渗出性脉络膜视网膜病变患者由于脉络膜新生血管（CNV）及其伴随的出血、渗出，严重损害患者的黄斑中心凹功能，从而形成绝对中心暗点影响中心视力，患眼出现中心外视力和偏心注视。按常规方法进行视野检查时，不能正常反映黄斑中心凹的功能，需对其进行视轴校正。     

视神经萎缩的暗适应研究——视力性质与暗适应曲线

根据夏德昭的视力性质分析,视神经萎缩存在着中心与中心外两种固视状态,以及测量偏心固视患者视野暗点时,必须先将视线矫正到暗点计注视目标,而后按常规测量方可保证正确的测量结果等报导,用Goldmann-Weekers 暗适应计并改装了该仪器的注视灯,开展对中心与中心外固视的视神经萎缩眼暗适应曲线的测定。分别比较中心与中心外固视眼矫正前后黄斑区域与全域视网膜的暗适应功能,以此和临床检查结     

视力性质分析在黄斑裂孔的应用

目的评价黄斑裂孔的视力性质。方法对20例全层黄斑裂孔和10例板层黄斑裂孔及10例囊样黄斑变性患者进行了中心暗点及固视性质检查。结果20例全层黄斑裂孔患者都存在中心绝对暗点，视力性质为中心外固视；而10例板层黄斑裂孔和10例囊样黄斑变性患者都无中心绝对暗点，视力性质为中心固视。结论全层黄斑裂孔的残留视力为中心外视力，视网膜上存在中心绝对暗点。     

青年性黄斑出血性脉络膜病变

本文报告青年性黄斑部视网膜下新生血管即黄斑出血性脉络膜病变共30例(女17,男13),发病年龄10—49岁,平均为29.5岁。均为中心视力突然下降。平均视力为0.36,一半病例有视物变形,中心暗点及旁中心暗点,单侧病变26例,双眼患者4例。发病早期在黄斑部有局限性视网膜感觉层的浆液性脱离,表面隆起,周围有环形的     

不同注视性质的远视性弱视儿童黄斑区视网膜厚度分析

目的:通过对4~8岁远视性屈光不正性弱视患儿注视性质、黄斑各分区视网膜厚度的测量、眼轴长度的检查,探讨远视性弱视儿童注视性质与其黄斑各分区视网膜厚度间的相关性;并进行远视性弱视儿童视网膜厚度及其相关因素的研究。方法:前瞻性非随机同期对照研究试验。将2018-09/12首次就诊且之前未进行过任何弱视训练的患儿共计44例57眼纳入该研究。选取屈光不正性远视性弱视儿童36眼作为远视性弱视组,视力正常儿童21眼作为正常对照组,两组均利用光学相干断层扫描技术(OCT)进行黄斑各分区视网膜厚度测量;同时将入组患儿在直接眼底镜检查下分为黄斑中心注视组32眼,旁中心注视组25眼,进行黄斑各分区视网膜厚度测量;用SPSS19.0统计软件分别分析两组间视网膜厚度及差异。结果:黄斑中心注视组在黄斑中心凹、黄斑内环鼻侧处视网膜厚度均小于旁中心注视组(P<0.05);而两组间余黄斑各分区视网膜厚度对比均无差异(P>0.05)。远视性弱视组的黄斑中心凹、黄斑内环鼻侧、黄斑内环下方及黄斑外环上方处视网膜厚度均大于正常对照组(P<0.05);而两组黄斑区内环颞侧、上方、外环鼻侧、外环颞侧、外环下方处视网膜厚度比较均无差异(P>0.05)。远视性弱视组眼轴长度较正常对照组短(P<0.05)。结论:黄斑中心注视儿童在黄斑区中心凹、内环鼻侧处视网膜厚度增加;远视性弱视儿童在黄斑区中心凹、内环鼻侧、内环下方、外环上方处视网膜厚度增加;远视性弱视儿童眼轴长度变短。     

放射性视神经病变临床分析

目的 探讨放射性视神经病变(RON)的临床特点、影响因素、诊治方法及其转归.方法 回顾性系列病例研究.对1999年6月至2010年10月中山大学中山眼科中心收治的35例(60只眼)RON住院患者的临床资料进行回顾性分析.结果 共收集35例(61只眼)RON患者的临床资料.所有患者均以进行性、无痛性单眼或双眼视力下降为主要表现.18例(51.4％)在完成放射治疗后3年内出现眼部症状.43只眼(70.5％)的患眼入院时中心最佳矫正视力＜0.05或视野0°.可窥见眼底的52只眼中,41只眼(78.8％)视乳头边界清晰,11只眼(21.2％)视乳头水肿和(或)出血、渗出.视乳头边界清晰的41只眼中,视乳头正常6只眼(14.6％),视乳头色较淡30只眼(73.2％),视乳头苍白5只眼(12.2％).14只眼有视野检查记录,主要表现为神经纤维束损害性视野缺损,其中7只眼(50％)表现为上方和(或)下方弓形暗点,3只眼(21.4％)出现中心和(或)旁中心暗点,2只眼伴生理肓点扩大,1只眼伴旁中心暗点,1只眼见鼻上象限缺损.23只眼有视网膜荧光血管造影检查结果,主要的改变为视乳头低荧光和视网膜毛细血管无灌注区.图形视觉诱发电位检查发现,83.3％出现振幅降低和(或)潜伏期延长.分别用糖皮质激素治疗、高压氧、高压氧联合糖皮质激素、视网膜激光光凝等治疗,只有10只眼(16.4％)视力有不同程度的改善.结论 RON潜伏期变异大,造成的视力和视野损伤重,视功能预后极差,主要眼部损伤为视网膜血管闭塞和不同程度视神经萎缩.目前针对并发症的保守治疗能短期改善视力.     

糖尿病视网膜病变激光术后视野的改变

目的报告增殖性糖尿病视网膜病变(proliferative diabetic retinopathy PDR)、严重非增殖性糖尿病视网膜病变(severe nonproliferative diabetic retinopathy severe NPDR)、糖尿病性黄斑水肿患者激光治疗后视野的改变.方法52眼分A、B、C三组.A组为无黄斑水肿的PDR及严重NPDR,行全视网膜光凝术(panretinal photocoagulation PRP).B组为PDR合并黄斑水肿者,行PRP联合黄斑区光凝.C组为单纯黄斑水肿者,行黄斑区光凝.结果A组光凝后,30°内视野平均光阈值敏感度下降(P＜0.01),周边视野暗点增多或增大.B组光凝后,30°视野平均光阈值敏感度下降(P＜0.01),周边视野暗点增大增多,10°内光阈值敏感度下降(P＜0.05).C组10°内视野平均光阈值敏感度下降(P＜0.05).三组激光治疗前后视力无显著区别,新生血管明显消退,黄斑水肿消退.结论全视网膜光凝可有效阻止PDR的进一步发展,防止病人视力进一步下降,但降低了视网膜光敏感度,且周边部视野暗点增多.黄斑区光凝不损伤黄斑中心视功能,对糖尿病黄斑部病变局部代谢的改善,促进组织修复有一定临床意义.     

Visual function and biofeedback training of patients with central vision loss: a review

Older individuals with macular diseases, such as age-related macular degeneration, experience central vision loss (CVL) due to degeneration of their photoreceptors and retinal cells. Patients with CVL may experience various vision impairments, including of visual acuity, fixation stability, contrast sensitivity, and stereoacuity. After CVL, most patients develop a preferred retinal locus outside the affected macular region, which serves as a new visual reference. In this review, we provide an overview of the visual function and impairment in individuals with CVL. In addition, the important role of biofeedback training on the visual function and activity of individuals with CVL is also reviewed. Accordingly, the location and development of the preferred retinal loci are discussed. Finally, this review discusses how to conduct biofeedback training to treat individuals with CVL.     

Biofeedback stimulation in patients with age-related macular degeneration: comparison between 2 different methods

Objective

To evaluate changes in patient’s visual performance after rehabilitation training with 2 different biofeedback training programs offered by the MP-1 microperimeter. Spontaneous retinal location of preferred retinal loci (PRLs) and fixation stability are not always optimal for best visual performances. MP-1 microperimeter biofeedback techniques have been suggested as modalities for training for better fixation stability and to find a better location of the new PRL in a more useful area of the retina in nonoptimal cases. The MP-1 microperimeter offers different biofeedback strategies, such as acoustic biofeedback and structured light stimulus plus acoustic biofeedback.

Design

Retrospective study.

Participants

Thirty subjects affected by age-related macular degeneration with absolute central scotoma.

Methods

A standard protocol of examination before and after visual rehabilitation training was performed on all study subjects. Assessment included demographics data, visual acuity, fixation stability, retinal sensitivity, and reading speed. Rehabilitation training was performed with standard and structured stimulus biofeedback. The whole sample was divided into 2 groups of 15 patients attending the 2 different stimulation training biofeedback.

Results

Mean reading speed was found to be significantly increased for both groups (p < 0.05 and p < 0.01). Also, a statistically significant improvement of fixation stability was registered for both groups (p < 0.01). Only patients trained with the flickering pattern biofeedback stimulation increased retinal sensitivity (p < 0.01).

Conclusions

Both regular biofeedback and flickering pattern biofeedback training seem to improve visual functions. More benefits seem to be accrued, however, with flickering pattern biofeedback training.     

特发性黄斑裂孔玻璃体切割手术后的视功能

目的：探讨特发性黄斑裂孔（IMH）玻璃体切割手术后的视功能状况，方法：复习并总结国内外相关文献资料，综合评述IMH玻璃体切割手术后视功能状况。结果：多数患者术后视力较术前提高2行或2行以上，并且主观感觉的视物变形和暗点，辨色力，双眼融合功能和立体视功能也有所改善，术后视野光敏度较术前有所提高；注视性质由术前的偏心注视多数恢复为主后的中心注视，然后部分患者视力的改善提高不显著甚至出现视力下降，部分患者黄斑裂孔虽然获得解剖愈合，但仍遗留某些视觉缺陷。影响术后视力和其他视功能恢复的因素是复杂的，通常与术前视力和视功能状况的好坏，病程长程，裂孔分期早期、手术方式，裂孔愈合状态以及手术合并症等诸多因素相关。结论：黄斑裂孔一旦发生，其裂孔愈合和视功能稳定的机会极少，因此多数学者主张若诊断明确应早手术封闭裂孔，评价玻璃体切割手术治疗IMH的疗效。应在解决形态愈合的基础上综合患者的视力，主观感觉及临床多项视功能进行全面评估。     

Fixation stability as a goal in the treatment of macular disease

Recent advances in the treatment of macular diseases have improved macular anatomy and function as measured and quantified by visual acuity, retinal thickness, and vascular changes detailed by fluorescein angiography. Such observed changes do not always explain improvement in visual function and do not always correlate with patient satisfaction. In some cases, there is poor correlation between anatomic changes and functional improvement. Microperimetry studies on fixation stability after treatment of macular diseases have shown a strong correlation between better fixation stability and visual acuity. Furthermore, achieving better fixation stability facilitates low-vision rehabilitation. These microperimetry findings suggest that fixation stability should be regarded as an important outcome measure in studies of macular disease treatment and should be considered in clinical and research studies of low-vision rehabilitation in cases of treated macular diseases.     

Microperimetry biofeedback training in a patient with bilateral myopic macular degeneration with central scotoma

Microperimetry-1 (MP-1) evaluation and MP-1 biofeedback training were done in a case of bilateral myopic macular degeneration with a central scotoma. Fixation behavior, location and stability of preferred retinal locus, eye movement speed, and mean sensitivity were assessed. The mean retinal sensitivities before, after and at 1-year after training in the right eye were 2.9 dB, 2.9 dB and 3.7 dB and in the left eye were 3.5 dB, 3.7 dB and 1.8 dB. The fixation point in the 2° gravitation circle, improved from 40% to 50% in the right eye and from 43% to 67% in the left eye. The average eye speed before, after and at 1-year after training in right eye were 0.19°/s, 0.26°/s and 0.25°/s and in left eye were 0.36°/s, 0.25°/s and 0.27°/s. Thus, biofeedback training using MP-1 can improve the visual function in patients with macular diseases and central scotoma.     

Resolution of macular scotoma after radial optic neurotomy in central retinal vein occlusion.

Radial optic neurotomy was performed on a hypertensive 65-year-old man with decreased vision in the right eye secondary to ischemic central retinal vein occlusion. Three months later, his visual acuity improved to 20/50. There was improvement in disc and macular edema, and reduction in retinal hemorrhages clinically and angiographically. Liquid crystal display microperimetry revealed improvement in fixation stability and macular sensitivity. Radial optic neurotomy appears to be an effective treatment alternative for selected patients with ischemic central retinal vein occlusion, and results in rapid improvement in visual acuity, central fixation, and macular scotoma as measured by a liquid crystal display microperimeter. Liquid crystal display microperimetry is a good and reliable alternative to the scanning laser ophthalmoscope for macular perimetry.     

Scotoma and fixation patterns using scanning laser ophthalmoscope microperimetry in patients with macular dystrophy

PURPOSE: We used scanning laser ophthalmoscope microperimetry to evaluate the retinal scotoma and the fixation points in the patients with macular dystrophy. METHODS: We studied 10 eyes of five patients with macular dystrophy (three patients with cone dystrophy and two patients with Stargardt disease). The mean patient age was 37 years (range, 13 to 64 years). An estimation of scotoma and fixation points on the retina was performed using scanning laser ophthalmoscope microperimetry. RESULTS: All 10 eyes (100%) had one of two types of dense scotoma: type one was a dense ring scotoma (five eyes, 50%), and type two was a dense central scotoma (five eyes, 50%) that included the center of the fovea. In all eyes with a dense ring scotoma, the fixation points were stable and did not shift. In all eyes with a dense central scotoma, the fixation shifted. The logarithm of minimal angle of resolution of the visual acuity in the eyes with the dense central scotoma was significantly worse than that of eyes with the dense ring scotoma type (P =.005). CONCLUSIONS: Scanning laser ophthalmoscope microperimetry findings demonstrate two types of dense scotoma (dense ring scotoma and dense central scotoma) in the patients with macular dystrophy. The two types of dense scotoma affect the shifting of the fixation points and the stability of fixation and may result in the difference in visual acuity in the patients with macular dystrophy.     

Eccentric fixation with macular scotoma

People with macular scotoma tend to read and visually scan more slowly than others with equivalently reduced visual acuity but intact central fields. We measured fixation eye movements and considered the contribution of fixation variability and centripetal eye drift to poor visual performance. These factors might confound efforts to consistently use an optimum retinal locus outside of the macula. We measured monocular horizontal and vertical eye movements using a search coil eyetracker while subjects with naturally occurring central scotomata or control subjects with simulated scotomata eccentrically fixated a single character that was sized to their visual acuity. Motivated subjects with long-standing stable maculopathies were chosen to estimate attainable performance limits. During attempts to eccentrically fixate, an ubiquitous foveal pursuit or centripetal drift tendency was not found; rather a pattern of drift was idiosyncratic from subject to subject. This finding was confirmed by an analysis of eye drift of 32 eyes with long-standing bilateral macular scotomata. Moreover, the eye drift speeds (15-200 minarc/sec) were too low to be of functional significance. Drift speeds during eccentric fixation with a visible target were not significantly different than those after the target was extinguished; however, drift speeds were greater than during foveal fixation. This suggests that the fovea has a specialized control of slow eye movements. Fixation variability increased with scotoma size for both simulated and real scotomata, with an abrupt rise when scotomata diameters exceeded 20 degrees C. A significant minority of subjects (39%) adopted two or more distinct preferred retinal loci (PRL) during fixation. Multiple PRL were also more likely if scotoma size exceeded 20 degrees C. Reasonably steady fixation is thus attainable when central scotoma sizes are smaller than approximately 20 degrees C.     

Patients with AMD and a large absolute central scotoma can be trained successfully to use eccentric viewing,as demonstrated in a scanning laser ophthalmoscope

Twenty patients with age-related macular degeneration, an absolute central scotoma and a mean visual acuity of 0.04 (20/475) were studied. A scanning laser ophthalmoscope (SLO) was used for microperimetry and determination of preferred retinal locus, often located to the left of the retinal lesion (corresponding to a location to the left of the visual field scotoma), which is considered unfavorable for reading. All 20 patients were trained to use a new and more favorable retinal locus for reading, above (or occasionally below) the retinal lesion (corresponding to a location below or above the visual field scotoma), first by reading scrolled text under simultaneous fixation monitoring and instruction in the SLO and then by reading printed text, using high magnification (mean 14.3x). For the 18 patients who learned to use eccentric viewing, reading speed with adequate magnification prior to training was 9.0+/-5.8 words/min. With training (mean 5.2 hours), it increased significantly (p<0.001) to 68.3+/-19.4 words per min. Training of eccentric reading has thus proved to be very successful.