Analysis Of Sonographic Features At Different Thyroid Function Status In Autoimmune Thyroiditis

Objective:To analyze the sonographic features of different thyroid function in autoimmune thyroiditis (AIT) and to assess the application value of ultrasonography in AIT thyroid function judgment and in clinical diagnosing and treating preliminary.Methods:Ultrasonography was performed in 102 patients who suffered from AIT and been diagnosed by endocrinology department from October 2009 to January 2011 in the The First People's Hospital of Yunnan Province. The patients were classified into three groups according to their thyroid function, including the euthyroid group, the hyperthyroidism group and the hypothyroidism group. The control group was 40 cases whose thyroid function, thyroid autoimmune antibody (TAA)level and the thyroid ultrasound examination were normal. The sizes and the diameter of superior thyroid arteries(STA) were measured routinely. The internal echo features of the thyroid parenchyma were observed, moreover, the distribution of the blood flow were checked by color Doppler flow imaging (CDFI). The peak systolic velocity(PSV), end of diastolic velocity (EDV), resistance index (RI)of STA and the heart rate(HR) of the patients were measured by the pulse Doppler ultrasound.Results:(1)Of the 102 cases suffering from AIT, Hashimoto's thyroiditis were found in 74 cases, postpartum thyroiditis (PPT) in 21 cases, silent thyroiditis in 4 cases and atrophic thyroiditis (AT) in 3 cases.20 cases was the euthyroid group,16 cases of the hyperthyroidism group and 66 cases of the hypothyroidism group. (2)Each size,the volume of thyroid and the diameters of STA in three groups of AIT were significantly greater than those in the control group (P<0.01). (3)Thyroid ultrasonic hypoecho-genicity was found in 96 cases (94.2%) out of 102 patients with AIT.The internal echo pattern in each group of AIT was significantly different from that in the control group (P<0.01). And the patterns observed in the euthyroid group and the hyperthyroidism group were mainly gradeâ… , there was no significant difference (P> 0.05), while the pattern was mainly gradeâ…¡-â…¢in the hypothyroidism group. There was a significant difference between the the euthyroid group and the hyperthyroidism group (P<0.01). (4)The blood supply of thyroid gland observed in the euthyroid group and the control group were mainly gradeâ… , there was no significant difference (P>0.05); while the blood supply observed in the hyperthyroidism and hypothyroidism group was more significantly abundant than that in the other two groups (P<0.05). The hyperthyroidism group was mainly gradeâ… -â…¡, the hypothyroidism group was mainly gradeâ…¡-â…¢. (5) STA PSV of the euthyroid group and the control group were in the normal range, and there was no significant difference between them (P>0.05). STA PSV of the hypothyroidism group and the hyperthyroidism group were significantly higher than those of the euthyroid group and the control group (P<0.01). (6)In the hypothyroidism group,there were 14 patients who received levothyroxine (L-T4) replacement therapy and their thyroid function returned to normal,39 patients untreated. Compared with the untreated subgroup each size and the volume of thyroid in the replacement to normal subgroup were decreased, the internal hypoecho increased, there was no significant difference (P>0.05). While the blood supply and STA PSV of the replace to normal subgroup were significantly lower than those in the untreated subgroup (P<0.05). (7)In the untreated subgroup, the degree of the pattern hypoechogenicity was inversely proportional to the serum TSH level.However, the serum TSH level was positively proportional to the blood supply of the thyroid gland. (8) In addition, of the 102 patients with AIT 2(1.9%) cases were found to be combination with papillary thyroid carcinoma(PTC). Irregular low echo masses had been found in the thyroid gland in one case, while in the other no masses had been observed. There was a large quantity of microcalcification in the 2 cases. Therefore, ultrasound suggested thyroid carcinoma and then they were confirmed as HT with PTC by pathology.Conclusions:(1) Ultrasonography is a better imagine method in the diagnosis of AIT, which can evaluate the thyroid function to a certain extent.(2) Ultrasonography can be used as one of the imagine methods in the clinical assistant evaluation of levothyroxine replacement therapy. (3) Ultrasonography is helpful to discover the thyroid carcinoma under the background of AIT.