| Hyperthyroidism is a very common clinical condition. The lifetime risk has been estimated at up to 5% in women (5). Subtype of hyperthyroidism is mainly determined by the level of iodine intake in the region. Nodular toxic goitre is most prevalent in iodine insufficient regions as opposed to diffuse toxic goitre (Graves’ disease) in iodine sufficient regions (7). Since surgery for hyperthyroidism is infrequently used in any part of the world, and since only a minority of patients on antithyroid drugs (ATD) will remit, it is not surprising that millions of patients have been treated with 131I since its introduction in the 1940s (1, 5). |
