Abstract: Objective To evaluate the contrast-enhanced CT features of mediastinal tuberculous lymphadenitis in adults with diameters more than 2.0 cm. Methods Twenty-one patients with 76 lymph nodes diagnosed as mediastinal tuberculous lymphadenitis by operation, mediastinoscopy and biopsy were evaluated on enhanced CT scan, including 13 male and 8 female. The median age of the patients was 28 years old (range from 16～60 years old). Results Five post-contrast patterns of enhancement were found: (1) inhomogeneous enhancement (35.3%);(2) peripheral rim enhancement (30.0%); (3) homogeneous enhancement (19.7%); (4) nonenhancement(7.9% ); (5) separate enhancement (6.6% ). 12 patients (57.1 %) had a combination of enhancement patterns. 9 patients(42.9% )had a single enhancement pattern. Conclusion Contrast-enhanced CT appearance of mediastinal tuberculous lymphadenitis with diameter≥2.0 cm was mainly inhomogeneous enhancement and peripheral rim enhancement. But peripheral rim enhancement or separate enhancement can suggest a diagnosis of tuberculosis.

Key words: Mediastinal, Tuberculosis,lymphnode, Tomography, X-ray computed