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1.
Kuo-yi Jade Chang MHealthEc MHM BSc Lisa Lorraine Dillon MSpecEd BPsych Lil Deverell COMS PhD MEd GradDipO&M BEd Mei Ying Boon PhD BOptom FAAO Lisa Keay PhD MPH BOptom 《Clinical & experimental optometry》2020,103(4):434-448
Despite orientation and mobility (O&M) being a significant factor determining quality of life of people with low vision or blindness, there are no gold standard measures or agreement on how to measure O&M performance. In the first part of this systematic review, an inventory of O&M outcome measures used by recent studies to assess the performance of orientation and/or mobility of adults with vision impairment (low vision and blindness) is presented. A wide variety of O&M outcome measures have been implemented in different fields of study, such as epidemiologic research and interventional studies evaluating training, assistive technology, vision rehabilitation and vision restoration. The most frequent aspect of outcome measures is efficiency such as time, distance, speed and percentage of preferred walking speed, followed by obstacle contacts and avoidance, and dis/orientation and veering. Other less commonly used aspects are target identification, safety and social interaction and self-reported outcome measures. Some studies employ sophisticated equipment to capture and analyse O&M performance in a laboratory setting, while others carry out their assessment in real-world indoor or outdoor environments. In the second part of this review, the appropriateness of implementing the identified outcome measures to assess O&M performance in clinical and functional O&M practice is evaluated. Nearly a half of these outcome measures meet all four criteria of face validity (either clinical or functional), responsiveness, reliability and feasibility and have the potential to be implemented in clinical or functional O&M practice. The findings of this review confirm the complicated and dynamic nature of O&M. Multiple measures are required in any evaluation of O&M performance to facilitate holistic assessment of O&M abilities and limitations of each individual. 相似文献
2.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments. 相似文献
3.
Alexander S. Dakos Ellen M. Walker Huai Jiang Barry E. Stein Benjamin A. Rowland 《The European journal of neuroscience》2019,50(11):3702-3712
Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex. 相似文献
4.
目的:比较双眼外直肌后徙术与常规疗法治疗斜视的临床疗效。方法:选取2016年6月-2017年6月笔者医院收治的128例斜视患者,按治疗方式不同分成对照组和研究组,每组各64例。其中对照组患者行常规单眼外直肌后徙联合内直肌缩短术(R&R),研究组患者行双眼外直肌后徙术(BLR-rec)。术后对患者随访1年,观察术后眼位正位率、欠矫率、过矫率,视觉功能恢复情况以及并发症发生率。结果:研究组患者正位率为89.06%高于对照组的68.75%,差异有统计学意义(P<0.05)。术前,对照组和研究组患者视近度、视远度和平均斜视度比较,两组患者融合功能和立体视功能占比比较,差异均无统计学意义(P>0.05)。术后,两组患者的斜视度较治疗前均出现了明显下降(P<0.05),且研究组治疗后斜视度下降幅度明显大于对照组(P<0.05);两组患者视觉功能恢复率均明显增加(P<0.05),且研究组恢复率明显大于对照组(P<0.05)。研究组并发症发生率明显低于对照组(P<0.05)。结论:双眼外直肌后徙术较单眼外直肌后徙联合内直肌缩短术有更好地临床效果,且安全性更高,值得临床推广。 相似文献
5.
6.
目的:探究超脉冲CO2点阵激光联合富血小板血浆(PRP)治疗面部痤疮凹陷性瘢痕的疗效。方法:72例面部痤疮凹陷性瘢痕患者,随机分为观察组(36例)和对照组(36例)。对照组采用超脉冲CO2点阵激光治疗,观察组采用超脉冲CO2点阵激光联合PRP治疗。比较两组患者的灰度差异、时间指标、瘢痕程度、疼痛、不良反应及视觉评估。结果:观察组的并发症发生率为11.11%,低于对照组的36.11%,差异具有统计学意义(P<0.05)。治疗后,两组患者的灰度差异率均减小,且观察组患者的灰度差异率显著低于对照组,差异具有统计学意义(P<0.05)。治疗后,观察组的炎性渗出时间、红肿时间、愈合时间、停工时间及瘢痕程度评分均低于对照组,差异均具有统计学意义(P<0.05);但疼痛度评分组间比较,差异无统计学意义(P>0.05)。结论:超脉冲CO2点阵激光联合PRP治疗面部痤疮凹陷性瘢痕效果较好,可有效降低瘢痕程度,减少治疗时间及并发症的发生,帮助患者迅速回归正常工作与生活,值得临床推广使用。 相似文献
7.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology. 相似文献
8.
目的 :探讨玻璃体切割术前 F- ERG与术后视力的关系。方法 :对 5 0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 .0 0 5 )。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。 相似文献
9.
Figure-Ground Segregation at Contours: a Neural Mechanism in the Visual Cortex of the Alert Monkey 总被引:1,自引:0,他引:1
An important task of vision is the segregation of figure and ground in situations of spatial occlusion. Psychophysical evidence suggests that the depth order at contours is defined early in visual processing. We have analysed this process in the visual cortex of the alert monkey. The animals were trained on a visual fixation task which reinforced foveal viewing. During periods of active visual fixation, we recorded the responses of single neurons in striate and prestriate cortex (areas V1, V2, and V3/V3A). The stimuli mimicked situations of spatial occlusion, usually a uniform light (or dark) rectangle overlaying a grating texture of opposite contrast. The direction of figure and ground at the borders of these rectangles was defined by the direction of the terminating grating lines (occlusion cues). Neuronal responses were analysed with respect to figure-ground direction and contrast polarity at such contours. Striate neurons often failed to respond to such stimuli, or were selective for contrast polarity; others were non-selective. Some neurons preferred a certain combination of figure-ground direction and contrast polarity. These neurons were rare both in striate and prestriate cortex. The majority of neurons signalled figure-ground direction independent of contrast polarity. These neurons were only found in prestriate cortex. We explain these responses in terms of a model which also explains neuronal signals of illusory contours. These results suggest that occlusion cues are used at an early level of processing to segregate figure and ground at contours. 相似文献
10.
J.I. Smedberg E. Lothigius I. Bodin A. Frykholm K. Nilner 《Clinical oral implants research》1993,4(1):39-46
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures. 相似文献