This prospective, observational study included all pediatric patients who were referred to the radiology department for neck ultrasonography between August-October 2018. A high-frequency probe was implemented and 220 patients were examined.

This prospective single-centered study was approved by the Institutional Review Board for Ethical Issues in Clinical Research and is compatible with the Declaration of Helsinki. The patients referred to the radiology department for the neck US with various clinical indications between August-October 2018 were included in the study. The informed consent was taken from the parents of the patients. The patients who had any systemic illness, were treated for malignancy or had any history of lower neck or chest surgery, were excluded.

The neck US was performed by two radiologists. The length of the extended thymus, from the upper margin of the manubrium to the superior edge of the thymic tissue on the transverse plane, was measured in millimeters and recorded.

al analysis of the data was performed in SPSS, Version 24 program (IBM, Armonk, New York). Pearson Chi-Square Test was used in comparing categorical data between groups.

Inclusion Criteria:

• The patients referred to the radiology department for the neck US with various clinical indications between August-October 2018 were included in the study.

Exclusion Criteria:

• The patients who had any systemic illness, were treated for malignancy, or had any history of lower neck or chest surgery, were excluded.

All patients referred to the radiology department for the neck US with various clinical indications between August-October 2018 were included in the study.