[Article in Italian]
Catalano O, Lobianco R, Esposito M, Sandomenico F, Siani A.
Servizio di Radiologia, Ospedale S. Maria delle Grazie, Pozzuoli NA.
PURPOSE: The
possibility of detecting contrast agent extravasation (i.e., active hemorrhage)
with dynamic conventional Computed Tomography (CT) in patients with abdominal
trauma has already been reported in small series. We report our experience in
the demonstration of contrast material extravasation using helical CT; we also
investigate the diagnostic and clinical value of this finding.
MATERIAL AND METHODS: January 1997 to July 1998, we examined
41 consecutive patients with upper abdominal trauma. Twelve patients (29%) had
contrast material extravasation. The examinations were performed with a helical
unit and volumetric acquisitions (thickness 8-10 mm, pitch 1, reconstruction
interval 5-8 mm). The intravenous contrast medium (350 mgI/mL, 130-140 mL) was
administered with rapid infusion (2-2.5 mL/s, 40-50 s acquisition delay from
bolus starting) and using a power injector. We reviewed the CT studies and clinical
records of these 12 patients. Contrast agent extravasation was considered present
when this finding, not recognizable on plain scans, showed equal attenuation
to or higher attenuation than the vessels within the same level. Moreover we
assessed leak site, CT appearance, the direct visualization of the involved
vessel, the evidence of other abdominal or extra-abdominal injuries, the CT
signs of hypovolemic shock, clinical and surgical data. For comparison, we finally
evaluated 50 examinations performed with a conventional CT scanner in subjects
with abdominal trauma.
RESULTS: Active hemorrhage involved the abdominal wall in 1
case (intercostal artery), the solid organs in 4 (splenic in 2, hepatic in 1,
of the middle hepatic vein in 1), the peritoneal cavity in 3 (splenic, midcolic,
and gastroduodenal artery in 1 each), the retroperitoneum in 4 (renal pedicle
in 2, renal parenchyma in 1, lumbar artery in 1). In all cases the site of contrast
extravasation corresponded at surgery to the site of active bleeding. The pattern
was localized in 10 cases and diffuse in 2. The involved vessel could be identified
in 5 cases while in the other ones the origin could be inferred from the leakage
site. Associated injuries of upper abdominal organs were seen in 11 of 12 patients
and extra-abdominal trauma in 6. In 4 cases there were CT features of hypovolemia.
One patient died during transport to the operating room and another after surgery,
while all the others survived. Contrast extravasation was identified in 9 (18%)
of the patients examined with a conventional CT unit.
CONCLUSIONS: Active contrast material extravasation can be
recognized with conventional CT scanners, though it has been considered a rare
finding. Helical CT seems to increase the detection rate and especially to boost
the radiologist's confidence in this diagnosis. Though active bleeding is identified
in severely-injured subjects requiring urgent intervention and may be associated
with findings of hypovolemic shock, it should not be considered itself as a
negative prognostic factor. Contrast extravasation is due to ongoing hemorrhage
and its detection is critical for urgent treatment. Accurate anatomical location
permits to choose surgical management or transcatheter embolization and thus
decreases time consumption for precise bleeding site identification.
Radiol Med (Torino). 1999 Mar;97(3):138-43.