Effectiveness of Training in Reading Rehabilitation for Patients With Diabetic Macular Oedema

Study Overview
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Brief Summary
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Diabetic macular oedema (DMO) is a sight-threatening problem for diabetic patient who has swelling in macula. Patients with DMO can receive laser treatment and achieve good acuity finally. However, some patients still have difficulties in reading even after proper treatment. In this project, the investigators aimed to explore the effectiveness of different training paradigms in improving reading performance in patients with DMO.

Detailed Description
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Patients with diabetic macular oedema (DMO), after receiving laser photocoagulation, achieved good outcomes in distance acuity. However, some patients, particularly those developing parafoveal scotoma, still had difficulty in reading. Inability to read or reading very slowly leads to the potential loss of job, as well as the enjoyment of reading for leisure. In this study, the investigators aimed to investigate the effectiveness of reading rehabilitation using perceptual learning paradigms in enhancing reading performance in patients with reading difficulties due to DMO. Also, the fundamental mechanisms explaining the reading problems in patients with DMO reading Chinese will be examined. The investigators hypothesize that the perceptual training would show an improvement in reading. The investigators' primary hypothesis is that temporal visual processing speed and spatial visual span will be improved after perceptual training. The investigators' secondary hypothesis is that the reading speed and fixation stability will be improved after training.

Official Title
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Effectiveness of Training in Reading Rehabilitation for Patients With Diabetic Macular Oedema (DMO)- Randomized Controlled Trial

Conditions
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Diabetic Macular Oedema, Parafoveal Scotoma

Intervention / Treatment
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* Other: Temporal Group
* Other: Spatial Group
* Other: Combined Group
* Other: Control Group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Able to read Chinese. No formal vision rehabilitation training in reading after vision loss Diagnosis of diabetic macular oedema (DMO) and had previous treatment with laser and / or intravitreal injections Reasonable control of blood glucose level (HbA1c <10) to minimize the impact of vision fluctuation Education level of 6 years or more (primary school or above) Exclusion Criteria: Receive any types of eye treatments other than those mentioned above Any diagnosed ocular diseases other than DMO Severe medical problems or self reported neurological or cognitive disorders Serious hearing impairment Previously attended vision rehabilitation clinic

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Temporal Group<br>Receive 6 weekly 1-hour training sessions by Trigrams (A tailor made reading-task training programme). | Other: Temporal Group<br>* Visual Processing Training<br>|
| Active Comparator: Spatial Group<br>Receive 6 weekly 1-hour training sessions by Trigrams (A tailor made reading-task training programme). | Other: Spatial Group<br>* Spatial visual span training<br>|
| Active Comparator: Combined Group<br>Receive 6 weekly 1-hour training sessions by Trigrams (A tailor made reading-task training programme). | Other: Combined Group<br>* Visual processing speed and spatial visual span training<br>|
| Placebo Comparator: Control Group<br>Receive 6 weekly 1-hour training sessions of leisure reading activities | Other: Control Group<br>* Leisure reading activities<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visual processing speed | Using trigrams to measure the character-recognition accuracy while characters are presented at different exposure times | Change from baseline at week 6 and change from baseline at week 12 week | 
| Change in visual span size | Using trigrams to measure the character-recognition accuracy while characters are presented at different positions | Change from baseline at week 6 and change from baseline at week 12 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in reading performance | Measured in three different ways for Chinese: Rapid serial visual presentation (RSVP) Sentence reading (MNREAD) Passage reading (IReST) | Change from baseline at week 6 and change from baseline at week 12 week | 
| Change in fixation stability | Fixation stability will be measured by MP-1 microperimeter. | Change from baseline at week 6 and change from baseline at week 12 week | 
| Change in Chinese version of Impact of Visually Impaired (C-IVI) measure | Self evaluated instrument to measure vision related restriction of participation in daily living. | Change from baseline at week 6 and change from baseline at week 12 week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Perceptual learning, Diabetic macular oedema, Hong Kong, Chinese