The Relationships of the Type of Needle and the Flushing of the Needle with the Satisfactory Rate of Thyroid Nodule Fine Needle Biopsy

Objective: To explore the factors that affect the satisfactory rate of fine needle aspiration biospy(FBAB)sampling of thyroid nodules and the effects of different needle types and needle flushing methods on the satisfactory rate of FNAB sampling. Methods: The clinical data of 190 patients with thyroid nodules (200 nodules in total) who underwent FNAB from June 2020 to December 2020 were analyzed. The relationship of the satisfaction rate of sampling with the type of puncture needle and the flushing method of the puncture needle was analyzed. Results: In 200 thyroid nodules, we found that the nondiagnostic rate (37%) with a larger needle (22G) was lower than that with a smaller needle (25G) (55%), and the difference was statistically significant (P < 0.05). In the analysis of the comparison of the satisfaction rate of the flushing of the puncture needle, it was found that the nondiagnostic rate of the flushing method was lower (24%) than that of the nonflushing method (68%), with a statistically significant difference (< 0.05). In the randomized test according to the size of the puncture needle and the flushing method, the nondiagnostic rates of the four groups (25G needle with flushing group, 25G needle without flushing group, 22G needle with flushing group and 22G needle without flushing group) were 34%, 76%, 14% and 60%, respectively. Moreover, there was no significant change in the diagnosis rate of benign and malignant lesions in the obtained samples (p=0.912). Conclusion: In fine-needle biopsy of thyroid nodules, a larger needle should be used in combination with the flushing method to reduce the nondiagnostic rate and improve the pathological diagnosis rate