Figure1a,b shows the CT scans of a 25-year-old male who was involved in a
road traffi c accident (RTA). Describe the fi ndings. Compare these with the CT
images in Fig.2a,b from another patient involved in an RTA.
2. What is the grading system most commonly used in renal trauma and how is each
grade managed?
3. What does Fig.3 show and what investigation should the patient undergo
prior to nephrectomy?
Figure1a,b shows the CT scans of a 25-year-old male who was involved in a
road traffi c accident (RTA). Describe the fi ndings. Compare these with the CT
images in Fig.2a,b from another patient involved in an RTA.
2. What is the grading system most commonly used in renal trauma and how is each
grade managed?
3. What does Fig.3 show and what investigation should the patient undergo
?prior to nephrectomy
figure1
Answers to Case
1. Figure1a,b are postcontrast coronal and axial CT images through the abdomen.
There is a crescentic low attenuation region following the convexity of the
left renal cortex, compatible with subcapsular haematoma. The left kidney is
normal. There is also linear low attenuation within the spleen, consistent with a
laceration and a small amount of free fl uid tracking medially from the spleen.
This is a Grade I renal injury.
Figure2a,b are post-contrast axial images through the kidneys showing a
low attenuation region posteromedially in the right kidney, extending into the
renal pelvis. In the context of recent trauma this represents a laceration. This
extends outside the kidney resulting in a perinephric haematoma or collection.
On the delayed phase image (Fig2b ) contrast excreted into the collecting
system has also leaked into the collection confi rming damage to the collecting
system i.e. grade IV injury.
2. The American Association for the Surgery of Trauma (AAST) classifi cation is
most commonly used:
Grade I – Renal contusion or small non-expanding subcapsular haematoma
associated with microscopic or rarely macroscopic haematuria.
Grade II – Parenchymal laceration (<1 cm) in renal cortex only. May be associated
with minor perinephric haematoma.
Grade III – Laceration (>1 cm) extending from cortex into medulla, but sparing
the collecting system. May be associated with signifi cant retroperitoneal
haematoma.
Grade IV – Laceration (>1 cm) associated with collecting system or segmental
renal vessel damage with contained haemorrhage or thrombosis within
vessel.
Grade V – Shattered kidney or renal vessel avulsion.
Blunt trauma causing grades I–IV trauma can usually be treated conservatively.
Life-threatening haemodynamic instability, due to renal haemorrhage, is
an absolute indication for renal exploration, as is an expanding or pulsatile perirenal
haematoma identifi ed at laparotomy performed for associated injuries.
Grade 5 vascular renal injuries are, by defi nition, regarded as an absolute indication
for exploration, though there have been reports of shattered kidneys being
managed conservatively. Penetrating injuries are frequently explored to exclude
abdominal visceral injuries. Renal injuries with urinary extravasation and devitalised
fragments may be managed conservatively or endoscopically if the patient
is haemodynamically stable. These injuries are, however, associated with an
increased rate of complications.
3. Figure.3 is a nephrectomy specimen following a road traffi c accident, the
lower pole was avulsed. This patient was haemodynamically unstable as a result
of a ruptured spleen and an expanding retroperitoneal haematoma was found at
laparotomy. A one-shot intra-operative IVU should be performed on the operating
table prior to nephrectomy if a normal contra-lateral kidney has not been
demonstrated on preoperative imaging