Summary: A 22-year-old African American man with sickle cell disease was
involved in a car accident and presented to the emergency department
with right-sided abdominal pain. The initial workup showed multiple rib
fractures, a liver laceration, and kidney lacerations. Initially he was
treated conservatively and was hemodynamically stable and afebrile. On
hospital day number 2, he developed fever and was treated with
antibiotics. He improved and was discharged on hospital day 9 with a
follow-up scheduled in 2 weeks. The patient presented to the emergency
department complaining of worsening abdominal pain, and 2 episodes of
emesis 4 days after discharge. No other symptoms were noted. Decreasing
hematocrit and hemoglobin led to a second contrast CT scan of the
abdomen and pelvis.
Summary:
Summary:
Diagnosis
Post-traumatic pseudoaneurysms and AV fistulas of the right renal artery
Findings
As a ligament injury was suspected to The CT scan at initial
admission showed a large right perinephric hematoma with contusions and
deep lacerations of the right mid-posterior kidney (Figure 1). On
delayed images, no extravasations from the renal collecting system were
noted. No hydronephrosis was seen. A small laceration of the liver was
also noted adjacent to the right adrenal gland. Atrophy of the spleen
was noted consistent with sickle cell disease. Gall stones were
incidentally noted.
The CT scan on return showed again the right
renal laceration with interval expansion of the perinephric hematoma and
pseudoaneurysm/hemorrhage in the interpolar region of the right kidney
with new distortion of the right renal cortex and suggestion of active
bleeding (Figure 1).
A right renal arteriogram showed 2 right
renal arteries (Figure 1). The more inferior accessory renal artery was
initially selected and revealed no evidence of active extravasation,
pseudoaneurysm, or arteriovenous (AV) fistula. Selection of the main
renal artery showed multiple areas of small pseudoaneursym formation and
active extravasations with AV fistula formation in the interpolar to
upper polar region of the right kidney(Figure 2). A 4 French cobra 2
catheter was advanced into a sub-segmental artery in the inter-upper
polar region supplying a large pseudoaneurysm and AV fistula. These were
coil embolized. Then a microcatheter was placed coaxially through the
cobra catheter and subsequently smaller pseudoaneurysm and AV fistulas
were coil embolized. A final arteriogram in the main renal artery showed
no evidence of pseudoaneurysm, active extravasations, or AV fistula
(Figure 2). About 25% of the right kidney was devascularized. No other
complications were noted.
Discussion
Renal artery pseudoaneurysms are rare after blunt abdominal trauma.
While they are common in penetrating injuries, only 20 cases after blunt
trauma have been reported.1 These are caused by decelerating
injuries of the renal artery after major falls or automobile accidents.
In blunt trauma, strong deacceleration forces may cause the arterial
injury. After the artery is completely or partially transected,
hemorrhage may be contained in the surrounding tissues such as the
vascular adventitia, Gerota’s fascia.2 Most patients present
with hematuria, flank pain,mass, or hypertension. Delayed hemorrhage
after renal trauma is a life threatening complication. Patients may be
asymptomatic for many years, and a chronic pseudoaneurysm may expand and
rupture before diagnosis or treatment. Treatment requires either
surgical or percutaneous intervention. Surgical treatment of
intraparenchymal aneurysm is usually partial nephrectomy or ligation of
the parental artery which causes large amount of parenchymal loss. The
angiographic approach can spare large portions of the involved kidney
and preserve renal function.3
Often the diagnosis of
renal artery pseudoaneurysm is made by CT, but magnetic resonance,
Doppler sonography and renal perfusion imaging can be used as well.
Angiography remains the gold standard to diagnose traumatic renal artery
pseudoaneurysm and may reveal smaller lesions than the other
techniques, as was demonstrated here.1 Moreover, with angiography concomitant therapeutic embolization can be provided.
Conclusion
Renal artery pseudoaneurysm after blunt abdominal trauma is uncommon but
can be diagnosed with standard radiographic techniques. Treatment
varies between open exploration and angiographic embolization. Minimally
invasive therapy by super selective trans-catheter embolization
provides permanent occlusion of the pseudoaneurysms that preserves
maximum renal function. Our case was successfully managed with selective
embolization without any medical complications.
- Mizobata Y, Yokota J, Fjuimura J, et
al. Successful evaluation of pseudoaneurysm formation after blunt renal
injury with dual-phase contrast-enhanced helical CT. AJR Am J Roentgenol. 2001;177:136-138.
- Lee DG, Lee SJ. Delayed hemorrhage from a pseudoaneurysm after blunt renal trauma. Intl J Urol. 2006;12: 909-911.
- Parildar M, Oran I, Memis A. Embolization of visceral pseudoaneurysms with platinum coils and N-butyl cyanoacrylate. Abdom Imag. 2003;28: 36-40.