| Bonnema et al., Odense, Denmark, assessed the effect of I-131 therapy in 23 patients with very large goiters on the reduction of intrathoracic goiter and measured inter- and intraobserver variation of MR images of the thyroid and upper airways and the validity of ultrasound goiter size estimation by planimetry. They found that radioiodine treatment has a similar reductive effect on intrathoracic and cervical goiter tissue. MR evaluation of goiter volume has a high intra- as well as interobserver precision but is less precise for calculation of tracheal dimensions. Ultrasound as compared to MR underestimates goiter volume when goiters are large. This underestimation increases with increasing goiter volume. (Comment: The results of these authors and of others on treatment of patients (even very old ones) with large goiters, are very favorable in that therapy is very effective and well tolerated. It is my opinion that in patients with large goiters, even if partially intrathoracic, treatment with radioactive iodine is, in general, the first option). Knudsen et al., Aalborg, Denmark, studied the effect of iodine intake, smoking and parity on goiter formation in 3.712 women randomly selected from the general population in Denmark. People were selected from 2 areas, one with mild and one with moderate iodine deficiency. They answered questionnaires concerning previous thyroid disease, parity, and smoking habits. Thyroid volume was assessed by ultrasound. Mean thyroid volume was 12.5 ml among parous women and 11.8 ml among nulliparous women (p = 0.007). Thyroid volume was strongly associated with parity among smokers, but not in non-smokers. This association was most pronounced in combination with iodine deficiency and young age. (Comment: Cigarette smoke contains thiocyanate that enters the blood and subsequently the thyroid and has antithyroid activity leading to goiter formation. It has also been shown that cigarette smoking is associated with GO in patients with Graves' disease. Here however the mechanism was suggested to be related to direct ocular damage by smoke and/or hypoxia-mediated ischaemic orbital injury). |
