The Effect of Thyroid Hormon Levels on the Corneal Measures

Thyroid hormone diseases can cause different symptoms and signs in the body according to the hormone levels, particularly in the eyes. Corneal tissue can be affected by many biochemical and hormonal factors, and many ocular surface and systemic diseases can affect the cornea.Hyperthyroidism has been shown to cause symptoms such as conjunctival chemosis, proptosis, increased intraocular pressure, limitation to globe movements due to the restriction of extraocular muscles, increased orbital volume, increased risk of glaucoma with inflammation in the trabecular meshwork and exposure keratopathy, especially in Graves' disease. In the case of hypothyroidism, studies have shown fluid retention and edema in all body tissues, thereby resulting in increased thickness in the cornea, as well as a decrease in corneal hysteresis, which increases the risk of glaucoma. In this study, it is aimed to assess whether thyroid hormone changes affect those parameters by objectively measuring corneal changes via corneal topography, corneal densitometry and corneal aberrometry.

Inclusion criteria

• Thyroid hormone disorder patients with a novel diagnosis
• Age-matched healthy individuals without any systemic disorder (e.g., diabetes mellitus, hypertension, rhematoid artritis, asthma etc.)

Exclusion criteria

• Having a spherical or cylindrical refractive error of >1.0 degrees,
• Congenital corneal dystrophies, corneal ectasia, corneal ulcers or scars, keratitis, ocular surface infections, keratoconus,
• A history of ocular trauma,
• Uveitis,
• Glaucoma,
• A history of contact lens wear,
• A history of ocular surgery,
• Dry eye diseases