Abstract
Purpose: :
Patients with thyroid associated ophthalmopathy (TAO) develop dry eye for many reasons. However, the main cause of dry eye in these individuals is that they have lid retraction that increases the ocular surface area and inflammation of the lacrimal gland decreases tear secretion and changes the composition of the tear fluid. We performed this study to investigate the relationship between autoantibodies such as thyroid stimulating antibody (TSAb) or TSH-receptor antibody (TRAb) and changes in the lacrimal gland in patients with TAO.
Methods: :
We studied 182 patients (mean age of 39.6 years) who had not yet started treatment for their thyroid disease. The height of the palpebral fissure, tear secretion, and levels of TSAb and TRAb were measured in each patient. Evaluation of their lacrimal glands was performed by MRI (Phillips T-10 NT), and the size of the lacrimal gland was measured in the coronal view.
Results: :
Enlargement of the lacrimal gland was seen in 20.8% of the subjects: 10.8% unilateral cases and 89.2% bilateral cases. In the 182 patients, deterioration of tear secretion, equal or less than 5 mm by the Shirmer test, was seen in about 20.6%, of which 25% are unilateral and 75% are bilateral. The levels of TSAb and TRAb were correlated with the size of the lacrimal gland by Spearman's rank-correlation coefficient (p<0.01).
Conclusions: :
Autoantibodies such as TSAb and TRAb may influence inflammation of the lacrimal gland in patients with TAO.
Keywords: autoimmune disease