A method of classification for hematomas of the rectus abdominis sheat
h (RSH) is proposed based on findings observed in CT in the 13 cases o
f RSH in the present study. Type I hematomas (five cases) are slight a
nd do not require hospitalization. Type II (three cases) and type III
(five cases) are moderate and severe hematomas, respectively, and do r
equire hospitalization. The patients with type III hematomas were all
undergoing anticoagulant therapy and presented with a picture of acute
abdomen, and in all five cases blood transfusion was carried out. Ult
rasonography and, in particular, CT permitted a correct diagnosis of R
SH. RSH should be considered (anticoagulant therapy induced) in female
s with sudden abdominal pain to avoid unnecessary surgical interventio
n.