[Nodular euthyroid goitre: value of ultrasonography versus scintigraphy in the initial assessment]

The aim of this study was to show that in exploration of nodular goiter with euthyroidy ultrasonography was higher than scintiscanning.

It was to show that when it was necessary to specify the topography and the number of thyroid nodules, the proportion of right results was larger with ultrasonography than with scinticanning. These proportions being respectively indicated Pe and Ps, hypothesis of search was formulated H1: Pe > Ps. Null hypothesis was written H0: Pe < Ps. Twenty three patients (21 women and 2 men with an average age of 41 years) carrying thryroïd nodules with euthyroidy had respectively undergone a scintiscanning (scintiscanning with sweeping after ingestion of iode 131) and an ultrasonography (conventional ultrasonography with a probe of 7.5 MZ) of the thyroid gland between February 26, 1996 and June 19, 1997. Per-operativedatahaving beenused as references from which the results of scintiscanning and ultrasonography were appreciated nominally, discreet: right results or false results. In this way, proportions of right and false results were collected respectively for scintiscanning and for ultrasonography, which made it possible to test null hypothesis (H0: Pe < Ps). The results were distributed on a 2 x 2 cotigence table. The chi 2 test was applied with a risk error of 5%.

For all patients the scintiscanning found on the whole a minimum number of 39 nodules contrary with ultrasonography and surgical exploration which respectively found a minimum number of 56 and 59 nodules. Comparison of right and false results had shown a superiority of ultrasonography (17 right and 6 false) on the scintiscanning (10 right and 13 false) with statistically significant difference (P < 0.05).

Ultrasonography is more precise when it is necessary to specify the number and the topography of the thyroid nodules. In addition ultrasonography is alleviating and less expensive compared to scintiscanning.