In 45 beta-thalassaemia heterozygotes and in 38 normal controls we det
ermined by ultrasound tomography: (a) the surface of the projection of
the spleen to thoracic and abdominal wall, (b) the maximum diameters
of the organ, and (9) its volume. The volume of the spleen is signific
antly bigger in heterozygotes as opposed to normals (132.94 +/- 41.76
and 80.29 +/- 25.88, respectively). In 17.8% of heterozygotes a palpab
le spleen was found. The findings of this study lead to the hypothesis
that in all heterozygotes the final volume of the organ is increased;
however, in only 17.8% of them a palpable spleen is found.