AAST splenic injury grading system

The American Association for the Surgery of Trauma (AAST) splenic injury scale, most recently revised in 2018, is currently the most widely used grading system for splenic trauma.

The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for visceral injury .

Classification

• grade I
  • subcapsular hematoma <10% of surface area
  • parenchymal laceration <1 cm depth
  • capsular tear
• grade II
  • subcapsular hematoma 10-50% of surface area
  • intraparenchymal hematoma <5 cm
  • parenchymal laceration 1-3 cm in depth
• grade III
  • subcapsular hematoma >50% of surface area
  • ruptured subcapsular or intraparenchymal hematoma ≥5 cm
  • parenchymal laceration >3 cm in depth
• grade IV
  • any injury in the presence of a splenic vascular injury* or active bleeding confined within splenic capsule
  • parenchymal laceration involving segmental or hilar vessels producing >25% devascularisation
• grade V
  • shattered spleen
  • any injury in the presence of splenic vascular injury* with active bleeding extending beyond the spleen into the peritoneum

Additional points

• advance one grade for multiple injuries, each up to grade III
• "vascular injury" (i.e. pseudoaneurysm or AV fistula) appears as a focal collection of vascular contrast which decreases in attenuation on delayed images
• "active bleeding" - focal or diffuse collection of vascular contrast which increases in size or attenuation on a delayed (i.e. later) phase

Imaging Technique

The AAST guidelines recommend dual arterial/portal venous phase imaging for evaluation of a vascular injury of the liver, spleen, and kidney .

Siehe auch:

• Milzruptur
• AAST liver injury scale
• subkapsuläres Milzhämatom
• spontane Milzruptur
• Renal trauma assessment

und weiter:

• Milzhämatom
• renal trauma grading
• AAST renal injury scale