Introduction

Tunnel vision is a condition that is described by the reduction and loss of an individual’s peripheral visual field. Restricted peripheral visual fields can impact an individual’s life and their daily tasks in many ways. For individuals with tunnel vision, low-vision aids are devices that can be used daily to support individuals and improve their quality of life. This article will explore the role of low-vision aids for individuals who have low-vision due to their restricted visual field (tunnel vision).   

Types of Low-Vision Aids

A myriad of aids such as:¹ 

• Magnifiers are a low-vision aid to support an individual by increasing the size of text, images or objects to make them easier to identify, especially as they have low-vision. There are a number of different magnifiers such as;^1,4
  • Hand magnifiers are the most common type of magnifier. The tool has a magnifying lens attached to a handle to enable short reading tasks such as reading a label or checking small objects like a buttonhole on a jacket. Hand magnifiers can come in a variety of shapes, sizes and magnification powers, some hand magnifiers come with a LED light to increase visibility for an individual.  
  • Hands-free magnifiers are tools that can be used for tasks that require both hands such as sewing or for individuals that have hand tremors or poor dexterity. There are different types of hands-free magnifiers such as: magnifiers that can be placed upon an individual’s glasses known as spectacle-mounted magnifiers, and telescopes which enable magnification through a mounted device.   
  • Stand magnifiers are tools that can be used for long duration tasks such as reading, puzzles, reviewing photographs. In a stand magnifier, a magnifying lens is attached to fixed legs and can be held closer to the eye to produce a clearer image and change the field of view for an individual. Some stand magnifiers can also include LED lighting to increase visibility for an individual using the tool.       
  • Digital magnifiers are also known as Electronic vision enhancement systems that use a camera to show magnified images on a screen for an individual. These tools can be found on desktop systems and portable systems, which gives individuals the ability to use a large screen to magnify objects or text, with the options to adjust the magnification, the colour contrast and brightness.
  • Binocular and monoculars are lightweight magnifiers. An individual can use binoculars for both eyes and for distance viewing such as watching entertainment in a theatre or looking for a bus number. An individual can use monoculars for one eye and for near as well as distance viewing.          
• Large print writing is where text ranges from size 16 to 18. Large print texts can be readily found at libraries and online via eBooks⁸ 
• Screen readers is software that can be used by individuals to listen to text being read out loud, which can help individuals to interact with a computer system⁹   

Benefits of Low-Vision Aids

Low-vision aids can provide individuals with low-vision (including tunnel vision) empowerment, confidence and independence in daily tasks.^5,11 The low-vision aids act as tools to enable easy recognition of objects, images and text. There is a wide selection of low-vision aids that can be beneficial for different viewing distances, different types of tasks, and the option of hand free magnification.^1,5 The magnification lens improves the field of view for an individual and clarity enabling better visibility of the object, text or image the individual is viewing.^5,10      

Choosing the Right Low-Vision Aid

Once an individual is diagnosed with low-vision (including tunnel vision), different colleagues can provide support from eye related charities, nursing teams and allied health professionals within an eye department.⁵ Colleagues can evaluate an individual with low-vision and guide them to select suitable types of low-vision aids to support their specific needs.^5,11 To ensure effective use of a low-vision aid, it is imperative for an individual’s eye structures to be assessed to ensure their functional vision and cognitive abilities are intact to enable full utilisation of the selected low-vision aid.^10,11 Eye professionals can also provide training and support for the individual as well their family and friends to ensure appropriate maintenance of the tools and follow-up care.¹¹  

Challenges

Low-vision aids can present various challenges as seen below:^5,7

• Access to low-vision aids - some surveys have shown that many regions and countries may lack adequate low-vision services. In some instances, services may be available, they may be limited to specialised centres and urban areas⁶ 
• Location of low-vision service - low-vision aid services are usually located in urban areas, therefore individuals in rural areas may have difficulty accessing the service due to the travel distance
• Awareness of low-vision aid service - a service like this could be considered as bespoke and therefore public awareness of the service can vary across different populations, thereby preventing individuals who would benefit from the service from accessing support
• Socioeconomic status - individuals with low-vision (including tunnel vision) from groups such as low-income backgrounds, those living in a rural area or, individuals with disabilities or refugee statuses, may face restrictions in the form of high travel costs, long travel distances, and lack of awareness of low-vision aid services due to location
• Referral for low-vision aid service - there are limited referral systems so individuals with low-vision may not receive timely support for visual aids
• Common misconceptions - the purpose and use of low-vision aids is often misunderstood
• Motivation and stigma - individuals may feel unmotivated, have low expectations or assume stigma around receiving aid support

Summary 

Low-vision aids can play a very supportive role for individuals with low-vision including those with tunnel vision. The low-vision aids can be used as tools to enhance an individual's quality of life and independence when performing daily tasks such as sewing, reading and navigating their environment. There are a variety of low-vision aids such as magnifiers, screen readers and large print books which can support an individual for different daily activities and for different distances (near and far viewing). Individuals are advised to receive an evaluation and guidance from eye professionals to select the right types of low-vision aids and support to utilise them and maintain the quality of the tools.  

FAQs 

What is the definition of an individual with low vision?

The World Health Organisation defines low-vision as an individual whose sight remains reduced even after treatment, with a vision of less than 20/60 (a poor visual measurement) but with a perception of light, or a reduction in a visual field of less than 10 degrees from a fixed point in an individual’s visual field.^2,3 

Can low-vision aids restore peripheral visual field loss?

Low-vision aids cannot restore visual field loss for individuals, but can enhance the remaining vision for individuals to support tasks in their daily lives. 

How can an individual maintain and care for their low-vision aids?

Low-vision aids usually come with care guidance but you can contact your local ophthalmology department or an ophthalmology related charity to ask for support.

What are key tips for individuals when using a magnifier?

An individual using a magnifier should start off with the lens close to their eye and then move the object close to the lens until the object is in focus for the individual.¹ It is usually advised for individuals to use their eye with the better vision to focus on the image through the lens.¹ To maintain the clear and steady view, an individual should avoid using the edge of the lens to read and try to keep the magnifier still and move the object instead.¹