Multidetector CT in Vascular Injuries Resulting from Pelvic Fractures: A Primer for Diagnostic Radiologists

Abstract

Pelvic vascular injuries are typically caused by high-energy trauma. The majority of these injuries are caused by motor vehicle collisions, and the rest are caused by falls and industrial or crush injuries. Pelvic vascular injuries are frequently associated with pelvic ring disruption and have a high mortality rate due to shock as a result of pelvic bleeding. Morbidity and mortality resulting from pelvic vascular injury are due to pelvic hemorrhage and resultant exsanguination, which is potentially treatable and reversible if it is diagnosed early with multidetector CT and treated promptly. The pelvic bleeding source can be arterial, venous, or osseous, and differentiating an arterial (high-pressure) bleed from a venous-osseous (low-pressure) bleed is of paramount importance in stratification for treatment. Low-pressure venous and osseous bleeds are initially treated with a pelvic binder or external fixation, while high-pressure arterial bleeds require angioembolization or surgical pelvic packing. Definitive treatment of the pelvic ring disruption includes open or closed reduction and internal fixation. Multidetector CT is important in the trauma setting to assess and characterize pelvic vascular injuries with multiphasic acquisition in the arterial and venous phases, which allows differentiation of the common vascular injury patterns. This article reviews the anatomy of the pelvic vessels and the pelvic vascular territory; discusses the multidetector CT protocols used in diagnosis and characterization of pelvic vascular injury; and describes the spectrum of pelvic vascular injuries, the differentiation of common injury patterns, mimics, and imaging pitfalls.

Diagnostic value of CT contrast extravasation for major arterial injury after pelvic fracture: A meta-analysis

“…In this context, there are several possible physiologic causes of false negative exams that can reduce sensitivity and adversely affect the utility of CE as a sign for ruling out arterial injury requiring hemostatic intervention. These include transient arterial spasm, hypotension, thrombosis, and tamponade (46)(47)(48).…”

Do we really need the arterial phase on CT in pelvic trauma patients?

“…Contrast extravasation on arterial phase CT is widely accepted as indicative of arterial hemorrhage, whereas contrast extravasation on portal venous phase alone is generally considered to be caused by venous bleeding (Fig. 4) [33,[40][41][42]. Such patients may have arterial bleeding from small arterial branches with extravasation too small to be seen on arterial phase CT, but it is assumed that these minor hemorrhages will not cause severe hemorrhagic hypotension and therefore should not lead automatically to angiography [19].…”

Commentary on “Multidetector CT in Vascular Injuries Resulting from Pelvic Fractures”

“…Raniga et al (1) provide a comprehensive discussion of the utility of CT for a potentially lethal and relatively common traumatic injury. Approximately 10% of patients admitted to level 1 trauma centers for blunt-force injury sustain pelvic fractures (2).…”

“…Taken as a whole, these features are used to predict the need for hemostatic intervention. Raniga et al (1) suggest that both angioembolization and retroperitoneal pelvic packing can be used as the first-line method to address high-pressure arterial bleeding. Most institutions favor angiography; however, some employ pelvic packing as an initial temporizing measure to avoid treatment delays associated with activation of the angiography suite.…”

“…Perhaps the most important pitfall highlighted by Raniga et al (1) relates to the diagnostic performance of contrast material extravasation. The authors note that contrast material extravasation is absent at CT when compared with catheter angiography in up to 20%-40% of instances, and that more than half of patients with contrast material extravasation at CT do not require embolization when digital subtraction angiography is performed.…”