[ARTICLE] The Effects of Compensatory Scanning Training on Mobility in Patients with Homonymous Visual Field Defects: Further Support, Predictive Variables and Follow-Up – Full Text HTML

 

Abstract

Introduction

People with homonymous visual field defects (HVFD) often report difficulty detecting obstacles in the periphery on their blind side in time when moving around. Recently, a randomized controlled trial showed that the InSight-Hemianopia Compensatory Scanning Training (IH-CST) specifically improved detection of peripheral stimuli and avoiding obstacles when moving around, especially in dual task situations.

Method

The within-group training effects of the previously reported IH-CST are examined in an extended patient group. Performance of patients with HVFD on a pre-assessment, post-assessment and follow-up assessment and performance of a healthy control group are compared. Furthermore, it is examined whether training effects can be predicted by demographic characteristics, variables related to the visual disorder, and neuropsychological test results.

Results

Performance on both subjective and objective measures of mobility-related scanning was improved after training, while no evidence was found for improvement in visual functions (including visual fields), reading, visual search and dot counting. Self-reported improvement did not correlate with improvement in objective mobility performance. According to the participants, the positive effects were still present six to ten months after training. No demographic characteristics, variables related to the visual disorder, and neuropsychological test results were found to predict the size of training effect, although some inconclusive evidence was found for more improvement in patients with left-sided HVFD than in patients with right-sided HFVD.

Conclusion

Further support was found for a positive effect of IH-CST on detection of visual stimuli during mobility-related activities specifically. Based on the reports given by patients, these effects appear to be long-term effects. However, no conclusions can be drawn on the objective long-term training effects.

Fig 1. Full study design. a Neuropsychological testing in the inclusion phase including Mini Mental State Examination [7], Trailmaking Test [8], Complex Figure of Rey [9], and Hospital Anxiety and Depression Scale [10]; b including the neuropsychological tests Nederlandse Leestest voor Volwassenen [11] and 15 Word Test [12,13]; c including the neuropsychological test Digit Span (subtest of the WAIS) [14]; d treatment—non-treatment comparison (RCT) [5]; e within-group comparison of training effect (analysis described in the present paper); FU = follow up.

Introduction

Homonymous visual field defects (HVFD) are caused by postchiasmatic brain damage and in most cases do not fully recover [1–3]. People with HVFD often report difficulty detecting obstacles located in the blind periphery in time when moving around. This may result in feelings of insecurity and even in collisions and may have a serious impact on participation in society [4].

Several training programs have been developed aimed at optimal compensation for the HVFD by adapting eye movements. One of these, the IH-CST (InSight-Hemianopia Compensatory Scanning Training), trains patients to apply a systematic, wide horizontal scanning rhythm. Recently, a randomized controlled trial (RCT) [5] showed that the IH-CST specifically improves detection of peripheral stimuli and avoiding obstacles when moving around, especially in dual task situations. No evidence was found for an improvement in visual functions (including visual field size), reading or searching for targets on a display.

In this paper, the within-group effects of the IH-CST are analyzed in a larger patient group than in the previously reported RCT [5]. Performance of patients with HVFD at the pre-assessment and post-assessment are compared with the performance of a healthy control group. The results of a follow-up assessment are reported, as well as the associations between subjective and objective performance. Furthermore, it will be examined whether the changes between the pre-assessment and post-assessment can be predicted by certain factors. As concluded in a recent systematic review of the literature on HVFD [6], more research is needed on the predictive variables of training effects. Knowing which variables are related to the effects of training would enable rehabilitation workers to deploy the best rehabilitation program for the individual patient. This may improve efficacy of rehabilitation. The potentially predictive variables are selected for their clinical relevance. In a rehabilitation setting, it is often questioned whether training effects can be predicted by demographic characteristics, variables related to the visual disorder, and neuropsychological test results [6]. In short, the aim of the present study is to examine the effects of IH-CST in terms of subjective and objective mobility-related measures, including the long-term effects and the influence of several factors on the effect of training.

Continue —> The Effects of Compensatory Scanning Training on Mobility in Patients with Homonymous Visual Field Defects: Further Support, Predictive Variables and Follow-Up

[CASE REPORT ARTICLE] The effects of short-lasting anti-saccade training in homonymous hemianopia with and without saccadic adaptation

Homonymous Visual Field Defects (HVFD) are common following stroke and can be highly debilitating for visual perception and higher level cognitive functions such as exploring visual scene or reading a text. Rehabilitation using oculomotor compensatory methods with automatic training over a short duration (~15 days) have been shown as efficient as longer voluntary training methods (>1 month).

Here, we propose to evaluate and compare the effect of an original HVFD rehabilitation method based on a single 15 min voluntary anti-saccades task (AS) toward the blind hemifield, with automatic sensorimotor adaptation to increase AS amplitude. In order to distinguish between adaptation and training effect, fourteen left- or right-HVFD patients were exposed, one month apart, to three training, two isolated AS task (Delayed-shift & No-shift paradigm) and one combined with AS adaptation (Adaptation paradigm). A quality of life questionnaire (NEI-VFQ 25) and functional measurements (reading speed, visual exploration time in pop-out and serial tasks) as well as oculomotor measurements were assessed before and after each training. We could not demonstrate significant adaptation at the group level, but we identified a group of 9 adapted patients.

While AS training itself proved to demonstrate significant functional improvements in the overall patient group , we could also demonstrate in the sub-group of adapted patients and specifically following the adaptation training, an increase of saccade amplitude during the reading task (left-HVFD patients) and the Serial exploration task, and improvement of the visual quality of life. We conclude that short-lasting AS training combined with adaptation could be implemented in rehabilitation methods of cognitive dysfunctions following HVFD. Indeed, both voluntary and automatic processes have shown interesting effects on the control of visually guided saccades in different cognitive tasks.

Source : http://journal.frontiersin.org/article/10.3389/fnbeh.2015.00332/abstract

[ARTICLE] The Effects of Compensatory Scanning Training on Mobility in Patients with Homonymous Visual Field Defects: A Randomized Controlled Trial – Open Access

Abstract

Introduction: Homonymous visual field defects (HVFD) are a common consequence of postchiasmatic acquired brain injury and often lead to mobility-related difficulties. Different types of compensatory scanning training have been developed, aimed at decreasing consequences of the HVFD by changing visual scanning.

Aim: The aim of the present study is to examine the effects of a compensatory scanning training program using horizontal scanning on mobility-related activities and participation in daily life.

Method: The main interest of this study is to assess the effectiveness of training on mobility-related activities and participation in daily life. Visual scanning tests, such as dot counting and visual search, and control measures for visual functions and reading have been included as well. First, it is examined how performance on scanning and mobility-related measures is affected in patients with HVFD by comparing scores with scores of a healthy control group (n = 25). Second, the effect of training is assessed using an RCT design, in which performance of 26 patients before and after training is compared to performance of 23 patients in a waiting list control group.

Results: Self-reported improvements after training were found, accompanied by improvements in detecting peripheral stimuli and avoiding obstacles during walking, especially in dual task situations in which a second task limits the attentional capacity available for compensatory scanning. Training only improved mobility-related activities in which detection of peripheral stimuli is important, while no improvement was found on tests that require other visual skills, such as reading, visual counting and visual search.

Conclusion: This is the first RCT to evaluate the effects of a compensatory scanning training that is based on a systematic horizontal scanning rhythm. This training improved mobility-related activities. The results suggest that different types of compensatory scanning strategies are appropriate for different types of activities.

Continue —->  PLOS ONE: The Effects of Compensatory Scanning Training on Mobility in Patients with Homonymous Visual Field Defects: A Randomized Controlled Trial.

[ARTICLE] Difficulties in Daily Life Reported by Patients With Homonymous Visual Field Defects.Visual Fields

Abstract

Background: Homonymous visual field defects (HVFD) are common after postchiasmatic acquired brain injury and may have a significant impact on independent living and participation in society. Vision-related difficulties experienced in daily life are usually assessed using questionnaires. The current study 1) links the content of 3 of these questionnaires to the International Classification of Functioning, Disability and Health (ICF) and 2) provides analyses of vision-related difficulties reported by patients with HVFD and minimal comorbidities.

Methods: Fifty-four patients with homonymous hemianopia or quadrantanopia were asked about difficulties experienced in daily life because of their HVFD. This was performed during a structured interview including 3 standardized questionnaires: National Eye Institute Visual Functioning Questionnaire, Independent Mobility Questionnaire, and Cerebral Visual Disorders Questionnaire. The reported difficulties were linked to the ICF according to the ICF linking rules. Main outcome measures were presence or absence of experienced difficulties.

Results: The ICF linking procedure resulted in a classification table that can be used in future studies of vision-related difficulties. Besides well-known difficulties related to reading, orientation, and mobility, a high proportion of patients with HVFD reported problems that previously have not been documented in the literature, such as impaired light sensitivity, color vision, and perception of depth.

Conclusions: A systematic inventory of difficulties experienced in daily life by patients with HVFD was performed using the ICF. These findings have implications for future study, assessment and rehabilitation of patients with HVFD.

via Difficulties in Daily Life Reported by Patients With Homonym… : Journal of Neuro-Ophthalmology.