ObjectiveTo analyze the relationship between the ultrasonic characteristics of papillary thyroidcarcinoma（PTC）and the metastasis of lymph node posterior to right recurrent laryngeal nerve（LN-pr RLN）

and to explore thepredictive value of ultrasound in LN-pr RLN metastasis in PTC patients.MethodsA total of 135 patients with PTC whounderwent right thyroid or bilobe resection and right LN-pr RLN dissection in our hospital were included in this study

including 29 patients with LN-pr RLN metastasis（LN-pr RLN metastasis group）

and 106 patients without LN-pr RLN metastasis（No LN-pr RLN metastasis group）. The characteristics of clinical and ultrasound image between the two groups were analyzed.Multivariable Logistic regression analysis was used to analyze the relationship between the characteristics of clinical andultrasonic in PTC patients and LN-pr RLN metastasis.ResultsThere were significant differences in age<45 years

tumordiameter<1 cm

capsule involvement

enlarged lymph nodes in group Ⅵ of the right neck showed by ultrasound

BRAFV600 Egenemutation

and lymph node metastasis in the right side between LN-pr RLN metastasis group and No LN-pr RLN metastasis group（all P<0.05）. Multivariable Logistic regression analyses indicated that the ultrasound results of the metastasis of enlarged lymphnodes in group Ⅵ of right neck and the lymph nodes in the right neck were related to the LN-pr RLN metastasis（OR=5.916

6.571

both P=0.001）.ConclusionUltrasonography can predict LN-pr RLN metastasis in patients with PTC

and the metastasisof enlarged lymph nodes in group Ⅵ of right neck or lymph nodes in the right side cervical area has a certain predictive value forLN-pr RLN metastasis.