Visual Field Testing

The visual field test is an essential part of ophthalmic diagnostics, helping to identify and treat conditions that pose a potential threat to vision, such as glaucoma, retinal diseases, and other ocular disorders. At Újbuda Medical Center, we use state-of-the-art technology and highly trained ophthalmologists to provide the highest quality care to our patients.

This test is particularly important for those with a history of eye conditions or who experience symptoms such as reduced visual acuity or narrowing of the visual field. Below, we provide a detailed explanation of what a visual field test is, when it is recommended, how the process works, and what the normal values are.

What is a Visual Field Test?

The visual field test, also known as perimetry, is a specialized ophthalmic procedure aimed at assessing the visual field and identifying any potential visual field defects. This test is crucial for maintaining eye health, as it enables ophthalmologists to determine exactly which areas of the visual field are affected by any reduction or absence of vision.

During the test, the patient focuses on a fixed point while responding to lights flashing in various positions in their peripheral vision without moving their gaze. The test is typically conducted in a darkened room, where the patient’s head is kept still, and the device used for the test, called a perimeter, surrounds them. The perimeter is a dome-shaped apparatus with light sources that appear at different intensities and positions on its inner surface. This allows the ophthalmologist or assistant to accurately record which lights the patient can and cannot see.

The visual field test is especially important for early detection of eye diseases that develop slowly and go unnoticed, such as glaucoma. In its early stages, glaucoma often affects peripheral vision first, which might not cause immediate symptoms. However, with a visual field test, the signs of visual field narrowing can be detected early, allowing prompt and targeted treatment to begin.

Additionally, the test is a valuable diagnostic tool for conditions such as optic nerve atrophy, retinal detachment, eye tumors, and other neurological disorders that affect vision. The visual field test provides a detailed overview of the state of the visual field, aiding ophthalmologists in developing appropriate treatment plans and tracking disease progression.

When is a Visual Field Test Recommended?

The visual field test plays a crucial role in ophthalmic diagnostics, helping to detect and manage vision-related diseases before they cause significant symptoms or permanent vision loss. This test may be recommended for various individuals for different reasons. Below are some situations where a visual field test is advised:

Early Detection of Eye Diseases

Ophthalmic conditions such as glaucoma, optic neuritis, optic nerve atrophy, and retinitis pigmentosa can significantly affect the visual field. These diseases often develop slowly and initially impact peripheral vision, which patients may not always notice. The visual field test can detect early signs of visual field narrowing, allowing for quick and effective treatment.

Neurological and Hormonal Disorders

The visual field test is not only crucial for diagnosing ophthalmic disorders but also for neurological and endocrinological conditions. Frequent headaches, hormonal imbalances, or issues affecting brain structures, such as pituitary tumors, can also impact the visual field. In such cases, the visual field test helps in diagnosing the underlying condition.

Personalized Treatment and Monitoring

For patients already diagnosed with eye diseases or neurological conditions, regular visual field testing helps track disease progression and develop personalized treatment strategies.

Certain professions, such as drivers, pilots, or jobs where accurate and peripheral vision is critical, also necessitate visual field testing. The test ensures that the individual’s vision meets the required safety standards.

Causes of Visual Field Loss

Visual field loss, also known as field of vision loss, can occur for various reasons and can significantly impact daily life quality. Below are some of the most common causes of visual field loss:

Glaucoma (Green Star)

Glaucoma is one of the leading causes of visual field loss. This disease involves an increase in internal eye pressure, which can damage the optic nerve and gradually reduce the visual field. Early detection of glaucoma is critical, as untreated conditions can eventually lead to complete blindness.

Optic Nerve Atrophy

The optic nerve can deteriorate due to genetic predispositions, injuries, or circulation issues. Optic nerve atrophy leads to the progressive destruction of optic nerve cells, reducing the efficiency of visual information processing, which causes the visual field to narrow.

Retinal Degenerative Diseases

Various retinal degenerative conditions, such as macular degeneration or retinitis pigmentosa, can also cause visual field loss. These diseases involve the gradual destruction of retinal cells, particularly affecting peripheral vision. Retinal degenerative diseases are often progressive, and currently, there are limited treatment options.

Eye Trauma or Injury

Physical injuries, such as severe impacts or significant trauma to the eye, can also lead to visual field loss. In these cases, damage often occurs suddenly, and the effects can be temporary or permanent, depending on the severity of the injury.

Brain Damage

Damage to parts of the brain responsible for processing vision (such as the visual pathway or the occipital lobe) can also lead to visual field loss. This type of field loss can be caused by brain tumors, strokes, or other neurological conditions.

Other Causes

In rare cases, visual field loss can be a side effect of certain medications, exposure to toxic substances, or radiation. Although less common, it’s essential for affected individuals to be aware of these risks.

To diagnose and treat visual field loss effectively, it is crucial to undergo regular eye exams, especially if you have risk factors such as high eye pressure, family history, or previous eye trauma. At Újbuda Medical Center’s ophthalmology department, modern diagnostic tools are available to accurately identify visual field loss and its causes, ensuring the most suitable and effective treatment options for every patient.

Visual Field Test Procedure

The visual field test, or perimetry, is a specialized ophthalmic procedure crucial for assessing the visual field and identifying any potential damage. This test helps determine the extent of the visual field and the areas where the patient cannot perceive visual stimuli. Below is a detailed description of the visual field test procedure at Újbuda Medical Center:

Preparation

Before the test, the ophthalmologist conducts a thorough medical history review, asking about the patient's past and current eye problems, as well as overall health. This helps identify potential risk factors and conditions that may affect the visual field.

Preparing the Test Environment

The visual field test is conducted in a darkened room to minimize external light interference. The patient must sit comfortably, and their head is stabilized using a stand to remain motionless during the test.

Test Procedure

The patient looks into a dome-shaped device, the perimeter, which surrounds them. Lights appear at random intervals and at different intensities on various points of the device's inner surface. The patient must indicate when they see the lights without turning their head toward the source. Typically, one eye is tested at a time, while the other is covered to provide an accurate assessment of each eye's visual field.

Data Collection and Evaluation

The perimeter automatically records the patient's responses, which the ophthalmologist evaluates to assess the visual field. The test results are displayed as a digital map, showing areas where the patient did not perceive the lights. This allows for the precise localization and measurement of visual field defects.

Discussing Results and Next Steps

After the test, the ophthalmologist explains the results to the patient, providing detailed information about what they mean in their specific case. If necessary, further diagnostic tests or treatments may be recommended to address the cause of visual field loss or prevent further deterioration.

Normal Values in a Visual Field Test

The normal parameters of the visual field are essential for early detection of eye diseases and developing effective treatment strategies. Below are the normal values and their significance in ophthalmology:

Central Vision

The central part of the visual field, also known as the central vision, provides extremely sharp vision. Normally, this area extends about 30 degrees, enabling detailed vision required for activities like reading and facial recognition.

Peripheral Vision

Peripheral vision covers the outer areas of the visual field and provides a wider angle of vision, which can extend up to 90 degrees. This part of the visual field is crucial for spatial awareness and detecting moving objects, aiding in safe navigation and quick recognition of environmental changes.

Visual Field Constriction

If the visual field is constricted, it indicates issues in processing visual information, often an early sign of eye diseases. Particularly in glaucoma or conditions affecting the optic nerve, such as optic neuritis or atrophy, the visual field may significantly narrow. Deviations from normal values, especially in peripheral vision, may require immediate medical attention.

Diagnostic Significance

Diagnosing deviations from normal visual field values is critical for developing appropriate treatment plans. The visual field test results help the doctor evaluate the extent and location of vision loss and track disease progression or treatment effectiveness.

Visual Field Test in Budapest

At Újbuda Medical Center, we offer the latest visual field testing services in the heart of the capital, using advanced technological developments and highly trained ophthalmologists. Don’t let vision problems affect your quality of life! Book an appointment online for an ophthalmology consultation, or call our central line at +36 1 550 7 550, where our staff is happy to assist you with scheduling and answering any additional questions.