Corneal Topography
CTP
Description
"Corneal Topography" scan maps the surface of your cornea in three dimensions to detect curvature issues, thickness changes, or structural deformities. It’s routinely done before LASIK or cataract surgery and can reveal keratoconus or astigmatism. The scan is fast, contact-free, and highly accurate. Results help tailor corrective treatments, fit custom contact lenses, or monitor progressive changes. Regular topography is key for surgical planning, early disease detection, and ensuring corneal health remains stable over time.
Category
Eye Function
Procedure
Non-Invasive
Sample Type
No biological sample is needed for this test.
Units
Not Applicable
Procedure Category
Scan
Test Group
Ophthalmological System Group
Test Group Description
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:
Result: Negative: No abnormalities detected.
Normal Range
For All Individuals:
Result: Negative: No abnormalities detected.
Results That Differ From The Norm (Direct and Indirect Causes)
Abnormal results may indicate:
Forme fruste keratoconus (subclinical or early stage of keratoconus)
Keratoglobus (rare condition characterized by thinning and globular protrusion of the cornea)
Keratoconus (progressive thinning and cone-shaped protrusion of the cornea)
Pellucid marginal degeneration (rare condition causing thinning of the inferior cornea)
Post-refractive surgery ectasia (corneal ectasia following refractive surgery)
Terrien marginal degeneration (progressive thinning and inflammation of the cornea)
Key Reasons For Testing
Corneal Shape and Curvature: Provides detailed insights into corneal shape, diagnosing conditions like astigmatism or keratoconus.
Refractive Surgery Planning: Helps map the cornea for procedures like LASIK or PRK.
Contact Lens Fitting: Ensures comfortable and effective contact lens wear by measuring the corneal surface.
Monitoring Corneal Diseases: Tracks progression of conditions like keratoconus or corneal dystrophies.
Post-Surgery Assessment: Evaluates corneal changes after surgery to optimize outcomes.
Corneal Health: Detects irregularities like scars, infections, or degeneration.
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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[10] Ambrósio R Jr, Caiado AL, Guerra FP, et al. Novel pachymetric parameters based on corneal tomography for diagnosing keratoconus. J Refract Surg. 2011;27(10):753-758.
[11] Buhren J, Kuhne C, Kohnen T. Defining subclinical keratoconus using corneal topography. J Cataract Refract Surg.2013;39(9):1351-1358.
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