Zhao H, et al. - Via searching PubMed, EMBASE and Cochrane Library databases, researchers identified relevant studies (up to September 2017) to assess the performance of preoperative ultrasound in the diagnosis of cervical lymph nodes metastases (CLNM) of papillary thyroid cancer (PTC) and determine its value in assisting cervical lymph node dissection (CLND). To assess the diagnostic efficacy of ultrasound in detecting central and lateral CLNM of PTC, overall sensitivity, specificity, and diagnostic odds ratio (DOR) were used. The meta-analysis included 19 studies that represented 4,014 patients. According to findings, preoperative ultrasound showed poor diagnostic sensitivity for central CLNM and good diagnostic efficacy for lateral CLNM of PTC. Due to the high incidence of central CLNM and low diagnostic efficacy of ultrasound, prophylactic central CLND is recommended for patients with PTC.