Evaluating and Managing Hematomas

Recommended Imaging Protocol

• The American College of Radiology recommends a contrast-enhanced CT scan with multiphase acquisition, including non-contrast, arterial, and portal venous phases, for evaluating hematomas, providing high spatial resolution, ability to detect active bleeding with high sensitivity (98%) and specificity (98%), and capacity to identify the source of hemorrhage 1, 2, 3
• The protocol recommendations for CT scans include non-contrast phase to determine hematoma age and contrast-enhanced phases to detect active bleeding, with oral contrast avoided in CTA as it can mask active bleeding 2, 3, 4

Interpretation of Imaging Results

• When interpreting the CT scan for hematoma, the radiologist should assess precise hematoma dimensions in three planes, presence/absence of active extravasation, mass effect on adjacent structures, development of complications, and relationship to surrounding anatomical structures, considering the entire gluteal region and potential extension into the pelvis or retroperitoneum 1, 2
• The presence of active extravasation, expanding hematoma, or new extravasation on follow-up CT scans may indicate the need for immediate intervention 2

Specific Considerations for Buttock Hematomas

• For buttock hematomas, it is essential to include the entire gluteal region in the scan field, evaluate for potential extension into the pelvis or retroperitoneum, assess for possible vascular injuries, particularly to gluteal vessels, and consider relationship to pelvic fractures if trauma-related, as recommended by the World Journal of Emergency Surgery 1

Follow-up and Management

• For stable patients, follow-up CT scans should be performed serially, with the first follow-up CT scan 24-48 hours after the initial scan, and subsequent follow-up scans every 1-2 weeks if the hematoma is stable or decreasing in size, with a final CT scan at 3 months to document resolution 2, 1
• For unstable patients, immediate intervention (angiography with potential embolization) should be considered 2
• CT scans are indicated when active bleeding is suspected or for pre-intervention planning, and have higher sensitivity for detecting active bleeding compared to conventional angiography, but may miss intermittent bleeding and have limitations such as contrast-induced nephropathy risk with repeated scans in patients with renal impairment 2
• Alternative imaging modalities, such as MRI, visceral arteriography, and ultrasound, may be considered in specific situations, but have limitations and are not recommended as the primary imaging modality for suspected abdominal hemorrhage 2, 3, 5

Imaging Modalities Comparison

2, 3, 5