High-frequency sonographic patterns of the spleen in children

To retrospectively evaluate the normal sonographic appearance of splenic parenchyma in children of various ages with high-frequency transducer sonography.

Research ethics committee board approval was obtained, with waiver of informed consent. We evaluated in vivo sagittal and transverse sonograms of spleens obtained with 13-MHz linear-array transducers in 100 children (age range, 1 day to 17 years) with clinically diagnosed disease that did not affect the lymphoid system. Three radiologists working in consensus defined the grading system for the splenic parenchyma. Thereafter, these same radiologists graded the sonographic reticulonodular pattern independently as granular, mild, or marked. These grades were cross correlated with clinical data by using logistic regression analysis and chi(2) tests. Sonographic measurements of the splenic parenchyma in nine pediatric cadavers separate from the in vivo cohort of the study were compared with those of corresponding histologic slices by means of linear correlation.

Both grade 2 and grade 3 patterns occurred more frequently in children older than 1 year but no older than 5 years, whereas grade 1 pattern occurred most frequently in neonates (P < .001). As patients' age (odds ratio, 1.6; P < .001) and splenic dimensions (odds ratio, 3.1; P < .001) increased, the frequency with which the reticulonodular pattern was classified as either grade 2 or grade 3 increased. No association was noted between sonographic patterns and body mass index (P = .85) or sex (P = .07). The parenchymal nodules graded as 2 or 3 on sonograms correlated well with the presence of lymphoid follicles (white pulp) at histologic analysis (r = .71, P = .03).

High-frequency transducer sonography of the spleen in children can demonstrate normal echo patterns that should not be misinterpreted as indicative of disease.