Perimetry

Perimetry Test or Visual Field Test

Perimetry test, also referred to as visually field test, is a diagnostic exam performed to measure both the size and quality of an individual's vision field. It evaluates their capacity to detect objects outside their direct line of vision; including peripheral and central vision.

Best Eye care centre for Visual Fields

This eye test plays an essential role in detecting vision field irregularities due to eye problems or neurological conditions. Its main purpose is to detect any abnormalities or visual field defects, such as blind spots or areas of reduced sensitivity.


Why Is Perimetry Important in Eye Care?

Here are a few reasons that illustrate the significance of this test:

  • Perimetry as an Eye Condition Detection Tool: It can assist in the identification and monitoring of many eye diseases, including retinal diseases, glaucoma damage to optic nerves and neurological issues. By measuring visual field loss patterns perimetry can aid in tracking their progression.
  • Functional Vision Assessment: Vision plays a crucial role in everyday activities like reading or driving as well as exploring one's surroundings. It can assess vision function by measuring eyes' ability to detect objects within different regions within their vision field. This data is invaluable in devising rehabilitation strategies as well as qualifying for certain occupations or activities.
  • Guide Treatment Choices: The results can assist ophthalmologists in making informed decisions about the most suitable treatments for eye diseases. By understanding the severity and location of visual field loss, medication, surgery or rehabilitation may be recommended to improve performance and quality of life.
  • Early and Progression Detection: Regular visual field tests enable early identification and progression detection in visual field loss. This allows for early intervention to help preserve vision while also avoiding further loss.
  • Evaluate Treatment Efficacy: It can be used to measure the efficacy of treatments designed to preserve or improve visual field. By comparing baseline and follow-up outcomes, health professionals can quickly ascertain whether their chosen approach works or if adjustments need to be made.
  • Education and Counselling of Patients: The results from this eye test provide evidence of the severity and impact of visual field loss, helping patients to understand their health condition better. Healthcare providers can discuss the implications of visual field issues while suggesting ways to optimize remaining vision.

Process of Visual Field Test

Visual Field test involves several steps:

  • Preparation: Gather all relevant medical history, current medications, contact lenses or eyeglasses that could interfere with testing, as well as any contact lenses or eyeglasses that might hinder it.
  • Explanation: Patients will be provided with information regarding the purpose and methods of the test to improve understanding and participation during it.
  • Positioning: A patient should sit in front of the machine with their head resting against its perimeter, using either a chin support or rest to adjust for optimal support of their head and equal eye level.
  • Calibration: Calibrating the machine ensures accurate measurements. This involves altering its sensitivity and levels of light according to standard parameters.
  • Focus on Fixation: Test subjects will be instructed to fixate on an established central point - usually a crosshair or light. This will ensure an even gaze throughout the test session.
  • Visual Field Testing: This tests begin by presenting a sequence of light stimuli at various spots within the visual field, typically small and dim lights of various intensities and durations that appear and disappear at various intervals throughout.
  • Button Press: When patients recognize light sources, it is suggested they press a button or respond in some other manner to signal its presence and help establish how well they are able to detect an object clearly. This allows us to evaluate their ability to discern stimuli accurately.
  • Mapping the Visual Field: The device tracks patient responses and produces a visual field map. This shows which areas in which they were able to detect stimuli being presented, or missed it completely.
  • Repeat Testing: Depending on the testing protocol, repeat tests can be run for various patterns or areas within your field of vision in order to gain comprehensive information.
  • Analyzing Data: Once collected data is analysed by a qualified healthcare professional, they interpret and determine visual field integrity within each patient as well as compare these results with normative values or prior tests.
  • Discussion of Results: The patient will receive an in-depth description of their visual field results by a healthcare professional. He or she will outline any anomalies, visual field defects or changes observed throughout their examination as well as discuss any implications resulting from these discoveries and offer guidance regarding further tests or treatments should additional medical help be necessary.

Applications of Visual Field Tests

Here are some of the most widely-used applications:

  • Diagnose of Eye Problems: Visual field tests can be used to accurately detect various eye conditions like glaucoma, optic nerve damage and retinal diseases as well as neurological diseases through mapping eye visual fields and testing their responses for any potential visual field problems that might indicate an underlying issue.
  • Monitoring Disease Progression: Visual field tests are an invaluable way of keeping track of eye conditions over time. By comparing results from visual field tests with prior ones, healthcare experts can better gauge stability or progression and make informed decisions regarding treatments and procedures.
  • Examining the Effectiveness of Treatment: Visual field tests play a vital role in evaluating treatments for eye problems. By comparing post-treatment and pre-treatment field results, health professionals can quickly ascertain whether or not their patient's vision has improved as a result of treatment.
  • Assessing Visual Impairment Visual field tests help healthcare providers assess the severity of visual impairment among people suffering from eye disorders or other conditions, by detecting areas of loss within the visual field. Healthcare providers can then ascertain its effect on daily activities as well as quality of life issues for each patient.
  • Surgery Planning: Visual field tests play a vital role in surgical planning for diseases like glaucoma. They provide invaluable information on the location and degree of visual field deficiency, providing surgeons with valuable data about its potential risks while making informed decisions regarding any planned procedures or their potential dangers.
  • Driver's License Test: Visual field tests are often necessary when applying or renewing for a driver's license, and must demonstrate sufficient vision field coverage to safely drive a car while meeting any specified vision requirements.
  • Research and Clinical Trials Tests of the visual field can be employed in clinical and research trials to collect data regarding visual fields, progression of eye disease, treatment outcomes and their effect. Such data are invaluable in improving our knowledge about eye disorders as well as devising more effective treatment and diagnostic strategies.

Perimetry vs. Confrontation Testing

Confrontation testing and perimetry are two techniques used to assess visual field, yet their methods of operation and purposes differ considerably. Let's compare both approaches:

Perimetry Confrontation Testing
  • It is an official and comprehensive examination of your field of vision. Usually carried out with special equipment like the perimeter or automated permemetry device.
  • It involves presenting visual stimuli at different positions within the visual field and monitoring how a patient reacts. Perimetry provides precise and comprehensive data regarding your degree of sensitivity and loss in visual field areas.
  • It is widely utilized as an aid in monitoring and diagnosing conditions like glaucoma, neurologic disorders and retinal conditions. Perimetry can reveal subtle visual field imperfections which might not always be apparent during daily tasks.
  • It provides a quick and informal way of diagnosing visually-related issues.
  • An optometrist or medical professional can perform it during a regular eye exam with simple tools like their hands or any other object, testing how a patient responds to visual stimuli presented at different locations within the eye field.
  • It provides a quantitative analysis of your visual area to detect any obvious irregularities or asymmetries in it, screening your field quickly to assess overall vision performance.
  • It is less precise and sensitive than perimetry, but may still help detect small visual irregularities. It could be especially useful in identifying visual field deficiencies which require further investigation or referral to formal perimetry services.
  • Conclusion: Perimetry offers an accurate and more precise method for evaluating the visual field, with precise measurements as well as detailed visually-based field mappings. Confrontation testing on the other hand serves as a quick screener that helps detect gross visual field defects quickly. Both techniques have their place within eye care, with each offering specific benefits depending on clinical needs or patient preferences.

Best Eye care centre for Visual Fields

Save Sight Centre in Delhi is widely recognized for being among the leading and most trusted centres for testing visual fields. Equipped with state-of-the-art technology and expert personnel, We offer unparalleled solutions in visual field evaluation.

Committed to exact and reliable results Save Sight has gained an outstanding reputation for their ability in assessing and monitoring conditions in the visual field, and provides exceptional care to its patients while accurately testing visual fields as well as conducting coehensive analyses of them - making Save Sight Centre an excellent choice when searching for reliable evaluation in Delhi.