For most nodules less than 4 cm, one treatment will sufficiently decrease the size of the nodules and improve symptoms. When nodules are close to vocal cord nerves, or with very large nodules, repeated procedures may be necessary. Untreated areas of “hot” nodules may interfere with the improvement in thyroid function. In these instances, complete ablation may be required. For this reason, more than one treatment session may be necessary to successfully treat “hot” nodules.