Prevalence, Size and Location of the Accessory Spleen in Children

The study was planned to evaluate the size, shape and prevalence of the accessory spleen (AS) in healthy children aged 1–18 years using their abdominopelvic computed tomography images. Pediatric subjects, who underwent abdominopelvic radiologic scan and admitted to the hospital between January 2011–December 2020 were included into the study for the detection of AS incidence. The antero-posterior, medio-lateral and supero-inferior diameters of AS and spleen were measured. In addition, the shape and localization of AS were noted. The study population consisted of 3738 normal pediatric subjects (2320 males and 1418 females) aged 1–18 years. AS was found in 461 (12.3%) of this population. In addition, 92 (19.7%) out of 461 cases had more than one AS. Of the subjects with AS, 292 were male and 169 were female. The dispersion ratio of AS incidence in males and females proved that AS incidence did not correlate with sex (p = 0.291). Measurements in males were statistically similar to those in females, excepts from the supero-inferior diameter of the spleen (p = 0.036), which was greater in males than females. According to age groups, AS size did not change after early childhood period, but the size of the spleen increased up to postpubescent period. The most common location of AS was the middle third of the main spleen (23.9%). There were two different shapes of AS: 80% were round and 20% were ovoid. Approximately one in eight children has an AS, which is round and well-marginated mass. It reaches adult size in late childhood period (i.e., from the age of six). Approximately one in four ASs was located at the middle third of the spleen.