Posts Tagged Vision restoration training

[Abstract+References] Combined Transcranial Direct Current Stimulation and Vision Restoration Training in Subacute Stroke Rehabilitation: A Pilot Study

Abstract

Background

Visual field defects after posterior cerebral artery stroke can be improved by vision restoration training (VRT), but when combined with transcranial direct current stimulation (tDCS), which alters brain excitability, vision recovery can be potentiated in the chronic stage. To date, the combination of VRT and tDCS has not been evaluated in postacute stroke rehabilitation.

Objectives

To determine whether combined tDCS and VRT can be effectively implemented in the early recovery phase following stroke, and to explore the feasibility, safety and efficacy of an early intervention.

Design

Open-label pilot study including a case series of 7 tDCS/VRT versus a convenience sample of 7 control patients (ClinicalTrials.gov ID: NCT02935413).

Setting

Rehabilitation center.

Subjects

Patients with homonymous visual field defects following a posterior cerebral artery stroke.

Methods

Seven homonymous hemianopia patients were prospectively treated with 10 sessions of combined tDCS (2.mA, 10 daily sessions of 20 minutes) and VRT at 66 (±50) days on average poststroke. Visual field recovery was compared with the retrospective data of 7 controls, whose defect sizes and age of lesions were matched to those of the experimental subjects and who had received standard rehabilitation with compensatory eye movement and exploration training.

Results

All 7 patients in the treatment group completed the treatment protocol. The safety and acceptance were excellent, and patients reported occasional skin itching beneath the electrodes as the only minor side effect. Irrespective of their treatment, both groups (treatment and control) showed improved visual fields as documented by an increased mean sensitivity threshold in decibels in standard static perimetry. Recovery was significantly greater (P < .05) in the tDCS/VRT patients (36.73% ± 37.0%) than in the controls (10.74% ± 8.86%).

Conclusion

In this open-label pilot study, tDCS/VRT in subacute stroke was demonstrated to be safe, with excellent applicability and acceptance of the treatment. Preliminary effectiveness calculations show that tDCS/VRT may be superior to standard vision training procedures. A confirmatory, larger-sample, controlled, randomized, and double-blind trial is now underway to compare real-tDCS− versus sham-tDCS−supported visual field training in the early vision rehabilitation phase.

References

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  18. Kasten, E., Bunzenthal, U., Sabel, B.A. Visual field recovery after vision restoration therapy (VRT) is independent of eye movements: An eye tracker study. Behav Brain Res. 2006;175:18–26.
  19. Nitsche, M.A., Schauenburg, A., Lang, N. et al, Facilitation of implicit motor learning by weak transcranial direct current stimulation of the primary motor cortex in the human. J Cogn Neurosci. 2003;15:619–626.
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Source: Combined Transcranial Direct Current Stimulation and Vision Restoration Training in Subacute Stroke Rehabilitation: A Pilot Study – PM&R

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[Abstract] Combined tDCS and Vision Restoration Training in Subacute Stroke Rehabilitation: A Pilot Study

Abstract

Background

Visual field defects after posterior cerebral artery stroke can be improved by vision restoration training (VRT), but when combined with transcranial direct current stimulation (tDCS) which alters brain excitability, vision recovery can be potentiated in the chronic stage. To date the combination of VRT and tDCS has not been evaluated in post-acute stroke rehabilitation.

Objective

To determine whether combined tDCS and VRT can be effectively implemented in the early recovery phase following a stroke, we wished to explore the feasibility, safety and efficacy of an early intervention.

Design

Open-label pilot study including a case series of seven tDCS/VRT versus a convenience sample of seven control patients (clinicalTrials.gov ID: NCT02935413).

Setting

Rehabilitation center

Subjects

Patients with homonymous visual field defects following a posterior cerebral artery stroke.

Methods

Seven homonymous hemianopia patients were prospectively treated with 10 sessions of combined tDCS (2mA, 10 daily sessions of 20 min) and VRT at 66 (±50) days on average post-stroke. Visual field recovery was compared with retrospective data of 7 controls, whose defect sizes and age of lesions were matched to the experimental subjects and who had received standard rehabilitation with compensatory eye movement and exploration training.

Results

All seven patients of the treatment group completed the treatment protocol. Safety and acceptance were excellent, and patients reported occasional skin itching beneath the electrodes as the only minor side effect. Irrespective of their treatment, both groups (treatment and control) showed improved visual fields as documented by an increased mean sensitivity threshold in dB (decibel) in standard static perimetry. Recovery was significantly greater (p<.05) in tDCS/VRT patients (36.73 ± 37.0%) than in controls (10.74 ± 8.86).

Conclusion

In this open-label pilot study, tDCS/VRT in sub-acute stroke was safe, with excellent applicability and acceptance of the treatment. Preliminary effectiveness calculations show that tDCS/VRT may be superior to standard vision training procedures. A confirmatory, larger-sample, controlled, randomized and double-blind trial is now underway to compare real- vs. sham-tDCS supported visual field training in the early vision rehabilitation phase.

This study was supported by the ERA-net neuron network “Restoration of Vision after Stroke (REVIS)”, (BMBF grant nr: 01EW1210).
clinicalTrials.gov ID: NCT02935413

Source: Combined tDCS and Vision Restoration Training in Subacute Stroke Rehabilitation: A Pilot Study

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[ARTICLE] Visual rehabilitation: visual scanning, multisensory stimulation and vision restoration trainings

Neuropsychological training methods of visual rehabilitation for homonymous vision loss caused by postchiasmatic damage fall into two fundamental paradigms: “compensation” and “restoration”. Existing methods can be classified into three groups: Visual Scanning Training (VST), Audio-Visual Scanning Training (AViST) and Vision Restoration Training (VRT). VST and AViST aim at compensating vision loss by training eye scanning movements, whereas VRT aims at improving lost vision by activating residual visual functions by training light detection and discrimination of visual stimuli.

This review discusses the rationale underlying these paradigms and summarizes the available evidence with respect to treatment efficacy. The issues raised in our review should help guide clinical care and stimulate new ideas for future research uncovering the underlying neural correlates of the different treatment paradigms. We propose that both local “within-system” interactions (i.e., relying on plasticity within peri-lesional spared tissue) and changes in more global “between-system” networks (i.e., recruiting alternative visual pathways) contribute to both vision restoration and compensatory rehabilitation that ultimately have implications for the rehabilitation of cognitive functions.

Download Provisional Article

via Frontiers | Visual rehabilitation: visual scanning, multisensory stimulation and vision restoration trainings | Frontiers in Behavioral Neuroscience.

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