Computed tomography depiction of normal inguinal lymph nodes in children.

ABSTRACT

BACKGROUND: The aim of the study was to establish computed tomography (CT) characteristics, distribution and provide normative data about size of normal inguinal lymph nodes in a paediatric population. MATERIALS AND METHODS: Four hundred eighty-one otherwise healthy children (147 girls, mean age 8.87, range 0-17 years) underwent pelvic CT in the setting of high-energy trauma were included in the study. Both axial and coronal 1.25-mm reconstructions were evaluated for the presence, location (deep or superficial), number, presence of fat attenuation, and shape of the lymph nodes, short-axis diameter of the biggest lymph node for each of right and left inguinal regions. RESULTS: A total of 7556 lymph nodes were detected in 481 subjects (the mean count of superficial and deep inguinal lymph nodes was 13.35 [range 6-23] and 2.36 [range 0-7] per subject, respectively) 15% (1135/7556) deep located, 85% (6421/7556) superficially located, 86.6% (6547/7556) with fat attenuation, 99.2% (7496/7556) oval in shape, 0.8% (60/7556) spherical. The short-axis diameter of the lymph nodes increased with age. Pearson's correlation coefficient for superficial and deep lymph nodes in boys and girls, respectively 0.538 (p < 0.001), 0.504 (p < 0.001), 0.452 (p < 0.001) and 0.268 (p < 0.001). The mean maximum short-axis diameters in different age groups and gender varied between 6.33 ± 0.85 mm and 8.68 ± 1.33 mm for superficial, 3.62 ± 1.16 mm and 5.83 ± 1.05 mm for deep inguinal lymph nodes. CONCLUSIONS: Inguinal lymph nodes were multiple, commonly contained fat, and were oval in shape. The data determined about inguinal lymph node size in different paediatric age groups may be applicable as normative data in daily clinical CT evaluation practice.