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The possible role of tear fluid thyroxine in keratoconus development
I L Kahán1, M Varsányi-Nagy, M Tóth
1Second Department of Ophthalmology, Semmelweis Medical University, Budapest, Hungary.
Experimental Eye Research
|April 1, 1990
Summary
Tear thyroxine levels are significantly higher in keratoconus patients compared to healthy individuals. These elevated levels correlate with disease progression, offering potential insights into corneal changes.
Area of Science:
- Ophthalmology
- Endocrinology
- Biochemistry
Background:
- Thyroxine (T4) is a key thyroid hormone.
- Thyroid dysfunction can affect various bodily systems.
- Keratoconus is a progressive corneal disease.
Purpose of the Study:
- To investigate tear thyroxine (T4) levels in keratoconus patients.
- To compare tear T4 levels between keratoconus patients and healthy controls.
- To explore the relationship between tear T4 levels and keratoconus progression.
Main Methods:
- Measurement of thyroxine levels in tear fluid and serum.
- Thyroid function tests (hypothyreotic, euthyreotic, hyperthyreotic) were performed.
- Tear T4 levels were analyzed in relation to ocular pathology and disease progression.
Main Results:
- Normal tear thyroxine levels are significantly lower (two orders of magnitude) than serum levels.
- Keratoconus patients exhibited 2-50 times higher tear thyroxine levels than controls, irrespective of thyroid status.
- Tear thyroxine levels increased during keratoconus progression and decreased upon stabilization of corneal curvature.
Conclusions:
- Tear thyroxine levels are a potential biomarker for keratoconus.
- Elevated tear thyroxine is associated with active keratoconus progression.
- Further research is warranted to understand the role of thyroxine in keratoconus pathogenesis.
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