Thyroid nodules are common in the population, especially when ultrasound machines have improved to a resolution of 1 mm, and the detection rate of thyroid nodules in a randomly selected population is as high as 70%, meaning that almost 2 out of 3 Chinese have nodules. Therefore, it is especially important to treat thyroid nodules, especially benign ones, correctly.
1. Is B-ultrasound or CT or MRI better for determining thyroid nodules?
There is a misconception among some patients that the more expensive the test is, the more accurate it is. However, in thyroid imaging, ultrasound is the most accurate way to determine benign and malignant nodules, and higher value CT and MRI are not as good, unless one wants to look at the goiter behind the sternum or suspects invasion of the surrounding soft tissues, including trachea, esophagus and blood vessels, then CT or MRI can be done.
However, the biggest disadvantage of ultrasound is that it is very subjective. Different doctors will have their own interpretation of the imaging changes they see, especially in the judgment of early nodules and lymph node metastases, so if you have doubts about the ultrasound results, it is best to have a review with an experienced ultrasound doctor at a large hospital.
2. How to interpret the description of nodules in thyroid ultrasound
The description of the ultrasound mainly looks at 3 points, in order of weighting: calcification – border – blood flow – aspect ratio.
”Calcification”: the description of ultrasound can be strong echogenicity, which can be seen in two cases: one is the change of gliosis, often in the accompanying surrounding echoless area, which is a sign of benignity, and one is calcification within the solid area, which is further divided into fine calcification and coarse calcification. The tiny calcification is mostly calcium salt deposition of malignant cells, and if there is typical fine calcification, its The possibility of malignancy is nearly 90%; coarse calcifications are generally benign lesions, but some scholars have calculated that there is also a malignant proportion of nearly 20% in patients with coarse calcifications.
”Border is not clear”: benign nodules generally have clear borders, malignant because there is invasion of the surrounding tissue, the border can appear burr-like changes, but sometimes inflammatory lesions, because there can be exudation, the border can also be relatively fuzzy.
”Abundant blood flow”: Abundant blood flow alone does not diagnose malignant nodules, but often inflammatory nodules can also be present, and such cases require close follow-up.
Ultrasound diagnosis of thyroid cancer has the following signs.
①Gravelly calcifications;
(2) Low echogenicity of the nodule;
③Rich blood supply;
④Irregular boundary of nodule with surrounding infiltration;
(5) The anterior-posterior diameter of the cross-section is larger than the left-right diameter. If there are three or more of these signs, thyroid cancer should be highly suspected, especially if there is gravel (fine sand) like calcification.
3.How to look at puncture biopsy
Although there is a controversy on whether to perform puncture biopsy on all suspicious nodules, it is undeniable that the preoperative means to confirm the diagnosis is fine needle aspiration cytology of thyroid nodules. However, because of the rich blood supply to the thyroid gland and the inability to effectively compress the area, puncture cannot be performed as coarse as a breast biopsy, but only fine needle aspiration;
The diagnosis of pathology can only be cellular, and the deviation from the histopathological diagnosis is about 15%, based on the high compliance rate also depends on the skills and experience of the puncture operator and cytopathologist, so the actual compliance rate may be even lower, while the current progress of B ultrasound technology, including the determination of elasticity index and contrast, the accuracy of B ultrasound diagnosis in some large hospitals has reached more than 90%, therefore, puncture in the diagnosis value may not be more advantageous than B-ultrasound.
4. How to treat benign nodules
The location of the thyroid gland is on both sides of the trachea, so it is not necessary to expect benign nodules to disappear if they do not have symptoms of pressure. There are no medications available to eliminate thyroid nodules, and although ultrasound ablation is now recommended in many hospitals, the chance of recurrence is very high.
Therefore, benign nodules do not need to be a major concern as long as they are not significantly larger, do not hurt, and do not affect thyroid function.