CT evaluation of spontaneously ruptured renal angiomyolipomas with massive hemorrhage spreading into multi-retroperitoneal fascia and fascial spaces

Background Renal angiomyolipomas (RAMLs) can spontaneously rupture and induce hemorrhage that is usually confined to the perirenal space (PS) but may spread beyond the PS into other retroperitoneal fascia and fascial spaces, including up to the subdiaphramatic and down to pelvic extra-peritoneal regions. Purpose To evaluate the computed tomography (CT) manifestations of renal angiomyolipoma (RAML) associated with spontaneous rupture and massive hemorrhage spreading beyond the PS into other retroperitoneal fascia and fascial spaces, including up to the subdiaphramatic and down to pelvic extra-peritoneal regions. Material and Methods The CT scans of seven patients with spontaneously ruptured of RAMLs and massive hemorrhage (surgically and pathologically confirmed) were retrospectively reviewed. We evaluated the CT signs of the RAML itself and the regions with extensive retroperitoneal spreading after RAML rupture. Results The CT manifestations of seven cases with RAML spontaneous rupture and massive hemorrhage included the following: (a) RAML signs: size (>4.0 cm, five patients;