Reading Training in Hemianopia - Pilot study

Rationale: A common consequence of stroke in the posterior region of the brain is a visual field defect. People with visual field defects frequently experience difficulties with reading, such as decreased reading speed, making more errors or being less able to read for a prolonged time. Reading difficulties due to a visual field defect have a severe impact on daily life activities, social participation and reduce quality of life. In The Netherlands, the provided rehabilitation options for these difficulties are currently not empirically supported.

Objective: This project aims to determine the feasibility of an RCT on the effectiveness of two reading interventions: Vistra and Rotated Reading. The effects will be investigated on the level of functions, activities and participation.

Study design: Feasibility pilot study of randomised controlled trial

Study population: Adult patients with reading difficulties due to homonymous visual field defects after acquired brain injury referred for care at a visual rehabilitation centre will be included in the study.

Intervention: The goal of Vistra is to learn patients to compensate for the visual field defect by training eye movements. Rotated Reading aims to reduce the effects of the visual field defect by learning people to read in a different direction, such as vertically or diagonally.
Main study parameters/endpoints: The main parameters are the objective and subjective effectiveness of the reading training. Effect measures are reading tests, reading questionnaires and vision-related quality of life questionnaires.

The objective of the feasibility pilot is to explore the following questions which will guide proper set-up of the RCT:
1. What is the number of potential participants registered monthly?
2. What is the number of potential participants accepting or declining study participation?
3. What is the percentage of participants completing the intervention + post-training assessment?
4. Are the eligibility criteria clear when put to practice?
5. Are the eligibility criteria adequate, too lenient or too strict from a clinical point of view?
6. Are the participants able to perform adequately on the tests and questionnaires during pre- and post-training assessment?
7. What is the duration of the pre- and post-training assessments in practice?
8. Are all devices and instruments present at all times at every assessment location?
9. Do the performances of the participants on the effect measures show enough variability?
10. Is the study protocol clear to all occupational therapists involved?
11. What is the subjective experience of the involved occupational therapists with the training protocols?
12. What is the subjective experience of the participants with the training protocols and study assessments?

RCT objectives:
Primary Objective:
1. To objectively compare and establish the effects of two reading training programs with each other and with a control group on reading performance.
Secondary Objective(s):
1. To establish the effect of the reading training programs on vision-related quality of life.
2. To identify common patient characteristics related to training outcome.

1-3 weeks before start of intervention
1-3 weeks after end of intervention
3 months after end of intervention

The goal of the Vistra training method is that patients with hemianopia gain insight in the nature of the visual field defect, the consequences this has for reading and to compensate for this during reading. Subgoals are increasing reading speed, reducing the number of errors, being able to read for a prolonged period of time and better understanding. The protocol consists of a reading exploration, training phase and an evaluation. Vistra comprises a large number of exercises of different nature and level of difficulty. All exercises aim at improving saccadic eye movements in the direction of the blind hemifield. Exercises are displayed on a computer screen and on paper. Between sessions, homework is given to the patients. The duration of the training is 10-12 sessions.

The rationale of Rotated Reading training is that people with hemianopia will be better able to read a text when it is rotated in a certain, personalized angle. The text is rotated to such an extent that the complete text emerges in the intact visual field, based on precise measurements of the visual field of the individual patient. The optimal rotation can be applied both digitally for training purposes and manually. For the latter a template is being used. The training starts with an exploration phase in which the patients gains understanding of the visual field defect and corresponding reading difficulties, after which face-to-face therapy and homework assignments help the patient to adapt to the rotation strategy. The duration of the training is 5 sessions.