An undetectable enlargement of the thyroid gland means that no goiter is detected during physical examination of the thyroid gland. Palpation of the thyroid gland can clarify the outline of the thyroid gland, palpation includes the examination of the isthmus of the thyroid gland and the lateral lobes of the thyroid gland, during palpation of the thyroid gland is not found to be enlarged suggests that no goiter was found. The thyroid gland is located below the thyroid cartilage, on both sides of the trachea, and consists of the central isthmus and the left and right side lobes, which are smooth and soft and not easy to touch under normal conditions. Generally, goiter is classified into three degrees and can be determined by palpation: I degree if the enlargement cannot be seen but can be palpated; II degree if the enlargement can be seen and palpated but within the sternocleidomastoid muscle; and III degree if the enlargement exceeds the outer edge of the sternocleidomastoid muscle. Pay attention to healthy diet, regular physical examination, if you find the neck mass or have uncomfortable symptoms timely hospital consultation, improve the relevant examination to clarify the diagnosis, under the guidance of a professional doctor for related treatment.