Abdominal CT: renal, ureter, and adrenal injury

Diagnosing renal injuries

Renal injuries follow a similar pattern to those in the spleen and liver.

Kidney lacerations

There can be relatively small lacerations or hematomas involving the cortex

Abdominal CT Trauma solid organ injury renal 5
Kidney laceration

Larger and deeper lacerations can injure the vasculature and result in active bleeding and retroperitoneal bleeding.

Abdominal CT Trauma solid organ injury renal 4
Kidney laceration
Shattered kidney and devascularization

Severe trauma can result in a shattered kidney, where the tissue becomes extensively injured and disrupted. When the injury extends to the hilum, there is potential for a vascular injury resulting in devascularization of portions of the kidney.

Abdominal CT Trauma solid organ injury renal 6

In the example below, there is absent enhancement of several segments of the kidney due to tissue and vascular injury, and these injured segments blend in with the surrounding perinephric blood.

Abdominal CT Trauma solid organ injury renal 3
Subcapsular hematoma

Sometimes blood from a renal injury accumulates under the renal capsule. This is called a subcapsular hematoma. You can recognize these by how they compress and distort the kidney shape compared to the uninjured kidney.

A large subcapsular hematoma compresses the underlying tissue, resulting in increased pressure on the kidney and impaired perfusion. Look at the compressed left kidney in our next CT image and notice that there is less enhancement and the cortex and medulla appear distinct from each other. Compare this to the normal right kidney which has uniform bright enhancement throughout.

Abdominal CT Trauma solid organ injury renal 2
Deceleration injury

Deceleration injury is a type of blunt trauma that occurs when a rapidly moving person is suddenly brought to a halt. These injuries can stretch the renal hilum where the vessels, nerves, and ureter enter the kidney. This can result in a traumatic dissection of the artery and result in multiple infarcts that look like peripheral, wedge-shaped defects.

Abdominal CT Trauma solid organ injury renal 1

Diagnosing ureter injuries

In severe renal trauma, you must also evaluate the ureter for injuries. Traumatic ureteral injury can result in a urine leak around the kidney and may be an indication for ureteral stenting or surgical repair.

When the initial scan shows a kidney injury, delayed images allow time for the kidneys to form contrast-opacified urine, similar to a urogram. In the case shown next, the patient had a smaller cortical laceration and blood surrounding the kidney.

Abdominal CT Trauma solid organ injury ureter 3
Cortical laceration

The next image from the same patient is at the level of the renal hilum. It shows more blood has leaked around the kidney from the small laceration seen in the previous image. You can also see that the renal pelvis is a bit dilated and there is dense material within it, suggesting some blood clots. This finding raises the concern of a collecting system injury.

Abdominal CT Trauma solid organ injury ureter 1
Cortical laceration

Delayed images obtained at 8 minutes allowed the kidney to produce contrast-enhanced urine. Notice how a thin layer of contrast leaks out and surrounds the kidney, indicating that the collecting system is injured.

Abdominal CT Trauma solid organ injury ureter 2
Collecting system injury

Diagnosing adrenal injuries

Adrenal injuries occur with severe blunt trauma to the abdomen.

The right adrenal gland is more commonly injured. This is because blunt force to the liver will compress the right adrenal into the vertebral bodies, resulting in a crush-type injury. Left adrenal injury is much less common.

Injury to the adrenal gland can appear in several different ways on CT imaging. In this first case, there is decreased or interrupted enhancement of the right adrenal gland, indicating injury and haematoma.

Abdominal CT Trauma solid organ injury adrenal 1
Injury and haematoma

In this second example, there are several small areas of active bleeding surrounding the haemorrhagic adrenal gland.

Abdominal CT Trauma solid organ injury adrenal 2
Active bleeding

Adrenal injury can also appear as ill-defined blood products with loss of a visible gland, or the adrenal gland can appear as a round mass.

Abdominal CT Trauma solid organ injury adrenal 3

This is an edited excerpt from the Medmastery course Abdomen CT: Trauma by Michael P. Hartung, MD. Acknowledgement and attribution to Medmastery for providing course transcripts


Radiology Library: Abdominal Trauma. Solid organ injury

Abdominal CT interpretation

Assistant Professor of Abdominal Imaging and Intervention at the University of Wisconsin Madison School of Medicine and Public Health. Interests include resident and medical student education, incorporating the latest technology for teaching radiology. I am also active as a volunteer teleradiologist for hospitals in Peru and Kenya. | Medmastery | Radiopaedia | Website | Twitter | LinkedIn | Scopus 

Dr Adam Brown LITFL Author

MBChB (hons), BMedSci - University of Edinburgh. Living the good life in emergency medicine down under. Interested in medical imaging and physiology. Love hiking, cycling and the great outdoors.

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