AN ASSESSMENT OF THYMIC TISSUE IN AUTOIMMUNE DISEASES

A technique of combined radiological and histological assessment of the thymus is described and has been carried out in a group of 85 patients suffering from chronic thyroiditis, non-toxic nodular goitre or thyrotoxicosis. The total amount of thymic parenchyma has been estimated by multiplying the maximum sagittal cross-sectional area of the thymus, determined radiologically, by the percentage of thymic tissue present in a biopsy, and this value has been termed the Corrected Thymic Size. The results have shown significant differences between the Corrected Thymic Sizes in these three diseases. Associations have been shown between the Corrected Thymic Size and the age of the patient in the thyrotoxicosis and non-toxic nodular goitre groups, and between this value and the anti-body titre and the duration of medical treatment in patients suffering from thyrotoxicosis.