Stroke And Lazy Eye: Is There A Link?

A stroke can cause a variety of eye problems, including dry eyes, swollen eyes, and even a lazy eye. A stroke occurs when blood that brings oxygen to the brain stops flowing and brain cells die. This can affect vision in different ways, such as visual field loss, eye movement problems, and visual processing issues. One of these eye movement problems is strabismus, or lazy eye, which is caused by an imbalance in the muscles that position the eyes, causing them to cross in or turn out, and preventing them from working together.

Strokes can cause visual field loss, including hemianopia, where half of the visual field is lost

A stroke can cause visual field loss, including hemianopia, where half of the visual field is lost. Hemianopia is a loss of half of a person's peripheral vision, meaning they lose either the right or left half of their vision in each eye. This condition can occur when a stroke damages areas of the brain responsible for vision, such as the occipital, temporal, and parietal lobes.

Hemianopia can significantly impact a person's daily life, making tasks like reading, writing, and navigating obstacles challenging. For example, when reading, words and sentences disappear when they fall within the missing visual field. Similarly, people with hemianopia may only be able to see half of someone's face. Other challenges include bumping into objects, difficulty moving in crowded areas, and increased risk of falls.

The impact of hemianopia on daily life underscores the importance of rehabilitation and adaptation strategies. Treatment options include prism glasses, which help bring the blind spot into the person's visual field, and scanning techniques that increase head and eye movements to compensate for the lost field of vision. Reading aids, such as coloured markers or line guides, can also be beneficial. While there is no cure for hemianopia, these interventions can help individuals adjust to their visual field loss and improve their quality of life.

In addition to hemianopia, strokes can also cause other types of visual field loss, such as quadrantanopia, the loss of either the upper or lower quarter of the visual field, and scotoma, a blind spot in one or both eyes. These vision problems are common after a stroke, affecting about 65% of stroke survivors. While full recovery of vision is rare, some improvement is possible, especially within the first few months after a stroke.

Strokes can cause eye movement disorders, such as diplopia (double vision) and nystagmus (wobbly eyes)

A stroke is a "brain attack" that occurs when the blood that brings oxygen to the brain stops flowing and brain cells die. Strokes can cause vision loss and about 65% of stroke survivors experience vision problems. Strokes can also cause eye movement disorders, such as diplopia (double vision) and nystagmus (uncontrolled eye movements).

Diplopia

Diplopia, or double vision, is a condition where a single object appears as two separate images. It is often caused by ocular misalignment, where the two eyes are pointed at different targets and thus see two different images. Diplopia can be monocular or binocular. Monocular diplopia is when a person sees double when one eye is covered. This is usually caused by refractive problems in one eye, such as high astigmatism, or by ocular abnormalities such as a dislocated lens. Binocular diplopia is when a person sees double when either eye is covered. This is usually caused by ocular misalignment due to brainstem, cranial nerve, neuromuscular junction, or extraocular muscle disease. Binocular diplopia may have a life-threatening cause and requires immediate referral.

Nystagmus

Nystagmus is the medical term for uncontrolled eye movements, which can occur from side to side or up and down. In patients with multiple sclerosis, nystagmus may not interfere with or impair their vision, and they may not even be aware that they have it. However, in some cases, nystagmus can affect vision, causing a sensation of moving objects, known as oscillopsia. While medications can be prescribed to control nystagmus, they do not work for everyone.

Strokes can cause visual hallucinations and recognition issues

A stroke is a "brain attack" that occurs when the blood that brings oxygen to the brain stops flowing and brain cells die. Strokes can cause vision issues, including reading problems, poor visual memory, and decreased depth perception and balance. Vision is the brain's process of gaining meaning from what we see, perceiving colour, size, and shape, and understanding the significance of what's in front of us.

Recognition issues can also occur after a stroke. This can include problems with identifying things (agnosia) and not being able to recognise faces (prosopagnosia). These issues are caused by damage to cognitive or language skills.

Strokes can cause dry eyes and sensitivity to light

A stroke is a "brain attack" that occurs when the blood that brings oxygen to the brain stops flowing and brain cells die. Vision problems are common after a stroke, with about 65% of stroke survivors experiencing some form of visual impairment.

Other eye problems that can occur after a stroke include visual field loss, eye movement problems, and visual processing problems. Visual field loss, or hemianopia, is the loss of one half of the visual field, which can cause difficulties with daily tasks such as reading, locating things, and navigating crowded environments. Eye movement problems can result in double vision and blurred vision, while visual processing problems can lead to visual neglect, where individuals are unaware of objects or people on their affected side.

Strokes can lead to visual neglect, or spatial inattention, where objects on one side are ignored

A stroke can cause a range of eye problems, including "lazy eye". However, it is important to note that "lazy eye", or amblyopia, is typically caused by abnormal visual development early in life, from birth up to age 7. It is characterised by reduced vision in one eye, with the weaker eye often wandering inward or outward.

Strokes, on the other hand, can lead to a variety of visual issues, depending on the location and extent of the brain tissue affected. This includes visual neglect, or spatial inattention, where people are not aware of or do not respond to things on their stroke-affected side. This problem is a result of damage to parts of the brain that perceive and interpret vision, rather than an issue with the eyes themselves.

Visual neglect can cause significant challenges in daily activities. For example, a person with neglect might ignore food on one half of their plate, neglect to shave or apply makeup to one side of their face, or be unaware of objects and people on their affected side, leading to bumping into them. It is more common when the stroke occurs in the right side of the brain, affecting the left side of the body.

Treatment for visual neglect typically involves the use of prisms, scanning techniques, and awareness strategies. However, if a person experiences both visual field loss and neglect, they are less likely to respond to scanning techniques.

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