Biometric and refractive changes after orbital decompression in Korean patients with thyroid-associated orbitopathy

Area of Science:

• Ophthalmology
• Endocrinology

Background:

• Thyroid-associated orbitopathy (TAO) is an autoimmune condition affecting the eye socket.
• Orbital decompression is a surgical procedure to alleviate proptosis and other symptoms of TAO.

Purpose of the Study:

• To evaluate biometric and refractive alterations following orbital decompression in Korean patients with TAO.
• To identify changes in axial length, anterior chamber depth, lens thickness, and refractive error post-surgery.

Main Methods:

• A retrospective observational study included 43 eyes from 23 Korean TAO patients.
• Ophthalmic examinations, including Hertel exophthalmometry and A-scan biometry, were performed pre- and 2 months post-orbital decompression.
• Autorefraction, corneal topography, and wavefront aberration measurements were also analyzed.

Main Results:

• Orbital decompression significantly reduced proptosis by 4.1 mm (P<0.001).
• Axial length increased by 0.08 mm (P<0.001) in 86% of eyes, correlating with a myopic shift (spherical equivalent decreased by 0.48 D, P<0.001).
• No significant changes were observed in corneal topography or wavefront aberrations.

Conclusions:

• Orbital decompression in TAO patients induces a myopic refractive change, primarily due to axial length elongation.
• Ophthalmologists should consider potential refractive changes, particularly myopia, in TAO patients experiencing decreased visual acuity after surgery.