Visual Acuity
VA
Description
Visual Acuity test measures how well the eye can distinguish shapes and details of objects at a specific distance, assessing overall clarity of vision. It’s commonly used to diagnose refractive errors like nearsightedness, farsightedness, and astigmatism. During the test, patients read letters or symbols from a standardized eye chart at different distances. Abnormal results may suggest vision problems that need corrective lenses or further eye exams. In some cases, results can also indicate underlying eye conditions that require more specialized testing. This test is especially helpful for people with blurred vision, difficulty focusing, or eye strain. Over time, this test can also track changes in vision, making it easier to detect problems before they affect daily life. Healthcare providers can use the results to determine whether glasses, contacts, or other treatments are required.
Procedure
Non-Invasive
Sample Type
No biological sample is needed for this test.
Test Category
Eye Function
Procedure Category
Assess
Units
Feet | Meters
Test Groups
Ophthalmological System Group: Tests within this group focus on evaluating the health and function of the eyes and visual system. These assessments provide insights into visual acuity, eye anatomy, and ocular health.
Optimal Range
For All Individuals:
Conventional Unit: 20/10 ft | 6/3 m
SI Unit: Not Applicable
Normal Range
For All Individuals:
Conventional Unit: 20/20 ft | 6/6 m
SI Unit: Not Applicable
Results That Differ From The Norm (Direct and Indirect Causes)
Abnormal results may indicate:
Amblyopia (Lazy eye)
Astigmatism (Irregular curvature of the eye's cornea or lens)
Cataracts (Clouding of the eye's lens)
Conjunctivitis (Pink eye)
Diabetic retinopathy (Damage to the retina due to diabetes)
Glaucoma (Optic nerve damage, often due to increased eye pressure)
- ...
Key Reasons For Testing
Assessment of Vision: Evaluates clarity and sharpness of vision, providing insight into vision quality.
Detection of Refractive Errors: Identifies refractive issues like myopia, hyperopia, and astigmatism for correction.
Diagnosis of Vision Disorders: Helps diagnose conditions such as amblyopia, strabismus, and cataracts.
Monitoring Eye Health: Tracks vision changes to detect diseases like glaucoma or macular degeneration.
Pediatric Vision Screening: Screens children for vision issues to enable early detection and treatment.
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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