Title: Homonymous Hemianopia in Childhood.
Funder: Health Education England

Abstract: Background Homonymous hemianopia (HH) in childhood can be caused by a variety of pathologies that affect one side of the brain, including tumor, stroke or trauma. Very little is known about children with HH, or how having HH in childhood affects their visual function and quality of life. Currently, there is little evidence to support any sort of intervention that can be offered to these children after diagnosis. In adults with HH, most commonly after stroke, prisms on the glasses of patients have been used for rehabilitation, increasing the functional visual field by up to 30 degrees. They have recently been shown to be beneficial in a double blind crossover clinical trial with sham prisms, but have yet to be trialed in children. Research questions What are the clinical characteristics of childhood HH? What is the impact of HH on affected children, young people and their families? Do horizontal prisms help children with HH compared to sham glasses? Would children with HH choose to wear prism glasses after cessation of the study?Aims and objectives The aim of this study is to better understand the clinical phenotype of homonymous hemianopia in childhood and the resulting effects on a child's visual function and visual related quality of life. Then to evaluate the use of prisms on glasses to help (re)habilitation of children with HH. Methods Phase one will be a deep clinical phenotyping of patients with HH, including visual related quality of life and visual function measures. The battery of clinical testing will include, orthoptic assessment, eye movement recordings, visual evoked potentials and optical coherence tomography. If participants meet the inclusion criteria for phase two they will be invited to enter the pilot randomized double blind controlled trial of real vs sham peripheral prisms. The glasses would be randomized and each worn for four weeks, without a washout period. Visual function would be measured using a questionnaire based tool, and utilizing an eye movement recording of a visual search task. Patient's responses would also be recorded. At the end of the trial patients would be de-briefed by an unmasked member of the team and asked if they would like to continue wearing the glasses. Timelines for delivery The project will be undertaken over four years. Anticipated impact and dissemination The major impact of this work will be providing evidence on the use of prisms for (re)habilitational of children with a diagnosis of HH. This evidence will hopefully inform current clinical practice. Furthermore, there will be a better understanding of this type of childhood visual impairment and the impact it has on a child's visual function and vision related quality of life. This will not only raise awareness of this type of childhood visual impairment, but also provide the groundwork for further research in this area.The work will be disseminated via the charities, as well as a newsletter to all participants. It will be presented at national and international meetings before being submitted for several publications.

Lay abstract: AimsThe aim of this study is to investigate the clinical phenotype of HH in childhood and the resulting effects on a child's visual function and vision related quality of life. Then to evaluate the use of prisms on glasses for children with homonymous hemianopia (HH). Background HH is the loss of one side of your vision, most often due to an injury of one side of the brain. Children can have a HH as a result of injuries such as a stroke, head injury or tumour. This can be difficult to diagnose, as these children can have additional disability, which masks the symptoms of vision loss. The consequences of losing a half of your vision at a young age are unknown. In adults this is relatively well understood, particularly as a result of stroke. Vision is involved in all aspects of life and children with HH have to achieve developmental milestones such as, learning to walk, and reading, at a significant disadvantage. Currently, apart from registration with visual impairment, there is very little information on what can be offered to children for rehabilitation of their HH. In adults with HH, most commonly after having a stroke, rehabilitation methods have been trialed to help patients. One of these is prism glasses, which help expand the non seeing visual field from zero to up-to 30 degrees at distance for navigational vision. These have been proven to help adults with HH compared to placebo glasses, but there has yet to be a trial looking at the use of these in children. Design and methodsThe project will consist of two connected pieces of work. The primary phase of the study will examine children with a diagnosis of HH to investigate the clinical spectrum, and undertake questionnaires to measure vision related quality of life and visual function of children with HH. If the recruited children met the inclusion criteria for phase two they would then be given the option of taking part in a pilot randomized cross-over trial of prism glasses and a placebo pair of glasses. The glasses would be randomized and each worn for four weeks. Visual function would be measured using a questionnaire based tool, and utilizing an eye movement recording of a visual search task. Patients responses would be recorded including 'if the trial was to end today - would you want to continue wearing these glasses?'. At the end of the trial patients would be de-briefed by an unmasked member of the team and asked if they would like to continue wearing the glasses. Patient and public involvement I've carried out patient and public involvement in the clinic at GOSH, with 'Eye Fact' posters explaining what Homonymous Hemianopia is. The project was presented at the GOSH Biomedical Research Centre NIHR family fun day with interactive activities to show children and adults the effects of a visual field deficit. I reached out to families of children with HH via social media asking them to participate in a questionnaire asking them to prioritise what research they would like in children with HH. Links have been established with several charities that support children with HH (CVI Scotland and The CVI Society). DisseminationAt all stages of the project participating families will have the option to opt in to receive bi-annual project updates and a final report at project close. Updates will be offered to the CVI society and CVI Scotland supporting charities to disseminate to members. Updates will be posted from a dedicated twitter account. It will be presented at national and international meetings before being submitted for several publications.

Research activity codes: 6.3 MEDICAL DEVICES
Health categories: EYE