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Paper text:
pseudoaneurysms are rare vascular lesions that result from the collection of blood between the tunica media and adventitia .
the majority of pseudoaneurysms are iatrogenic , and usually secondary to manipulation of the vascular structure .
pseudoaneurysms are at risk for rupture causing massive exsanguination , or thrombosis , which carries the risk of pulmonary embolism [ 2 , 3 ] .
a 24-year - old man was brought by ambulance to our facility after having been involved in an unhelmeted motorcycle collision .
he presented with sinus tachycardia up to 123 beats per minute , a glasgow coma score of 15 , and had an obvious deformity of the right lower extremity .
he was stabilized in a cervical collar and a sager traction splint on his right lower extremity and taken for ct scans of his head , cervical spine , chest , abdomen and pelvis as well as plain films of his extremities .
according to our institutional protocol , he underwent ct angiogram of his neck given his skull base fracture .
he was found to have a right kidney laceration with active extravasation , two large hepatic lacerations without active extravasation , a right midshaft femur fracture , bilateral distal radius fractures , a left occipital condyle fracture , a dissection of the left internal carotid artery , and pooling of iv contrast near the bifurcation of his inferior vena cava ( ivc ) .
1 ) . given his hemodynamic stability , we consulted the vascular and interventional radiology teams regarding management .
we decided to proceed with visceral arteriogram to control bleeding from the right kidney as well as a venogram to further delineate the suspected venous injury ( fig .
2 ) . 
 figure 1:a ct of the abdomen and pelvis taken on arrival ( day 1 ) showed a blush of contrast at the bifurcation of the common iliac veins . a ct of the abdomen and pelvis taken on arrival ( day 1 ) showed a blush of contrast at the bifurcation of the common iliac veins .
the visceral arteriogram demonstrated extravasation from the right adrenal artery and superior pole of the kidney , both of which were embolized with microcoils .
a venogram was then performed , which demonstrated a 2.8 cm pseudoaneurysm arising from the proximal portion of the left common iliac vein with involvement of the base of the ivc without active extravasation .
the patient continued to be hemodynamically stable so the decision was made to observe him .
after an initial hemoglobin drop from 14.3 to 6.9 g / dl within the first 48 h , he stabilized between 8 and 9 g / dl after two units of packed red blood cell transfusion and then remained hemodynamically stable throughout his stay .
he was initiated on aspirin and therapeutic heparin for his carotid dissection on hospital day 2 and underwent a cerebral angiogram and right internal carotid stent placement on hospital day 14 .
a ct venogram on hospital day 16 demonstrated a decrease in size of the pseudoaneurysm , and a stable prevertebral and pelvic retroperitoneal hematoma ( fig .
these were managed conservatively as the patient s hemoglobin and hemodynamics were stable . given the concern for intraluminal thrombus extension from the pseudoaneurysm , the decision was made to continue therapeutic anticoagulation .
he was bridged to warfarin on hospital day 17 and discharged to a rehabilitation facility on hospital day 20 on therapeutic anticoagulation and full dose aspirin . 

figure 2:an interventional radiology angiogram and venogram on day 1 showed a 2.8 cm pseudoaneurysm in the proximal portion of the left common iliac vein .
an interventional radiology angiogram and venogram on day 1 showed a 2.8 cm pseudoaneurysm in the proximal portion of the left common iliac vein .
venous aneurysms , both true and false , can be either congenital or acquired . in this case , the cause of the pseudoaneurysm is hypothesized to be blunt trauma creating compression on the ivc and proximal portion of the left common iliac vein , which then led to a puncture of the inner two vessel layers .
pseudoaneurysms of internal vessels can pose a diagnostic challenge as they can rarely be detected by physical examination and are often misdiagnosed . during this case pooling of contrast
was seen on ct scan , but formal diagnosis of a pseudoaneurysm was only made with a traditional venogram . as this case reinforces , venogram is the standard for diagnosing a venous pseudoaneurysm while ct angiography is adequate for surveillance of a venous pseudoaneurysm . 

figure 3:a ct angiogram of the chest with and without contrast on day 16 showed resolution of the pseudoaneurysm in the proximal left common iliac vein with clear flow at the ivc bifurcation .
a ct angiogram of the chest with and without contrast on day 16 showed resolution of the pseudoaneurysm in the proximal left common iliac vein with clear flow at the ivc bifurcation .
treatment for venous pseudoaneurysms should depend on the hemodynamic status of the patient as well as the location of the pseudoaneurysm .
goals should include early identification and control of exsanguination followed by recognition of and management of thrombosis .
peripheral arterial pseudoaneurysms with active blood flow , such as femoral arteries injured during catheterization , can be diagnosed with ultrasound and treated with ultrasonographically guided thrombin injection [ 5 , 6 ] .
other options include endovascular coil embolization , covered stent placement or operative repair [ 2 , 7 , 8 ] . however , the lack of literature on venous pseudoaneurysms limits evidence - based treatment .
case reports and small series suggest endovascular coil embolization or suture ligation as potential options .
our experience suggests that traumatic venous pseudoaneurysms can be observed in the hemodynamically stable patient . the proximity of the pseudoaneurysm to the ivc in our particular case made endovascular options limited .
the possibility of placing a bifurcated aortic device or two covered stents was felt to be unwise due to the larger diameter of these stents leading to risk of causing additional venous injury .
surveillance imagining demonstrated a stable retroperitoneal hematoma , which we believed to be a thrombosed pseudoaneurysm .
the patient has had no complications from the pseudoaneurysm as of follow - up 3 months later . in conclusion , we report a rare case of a traumatic common iliac vein pseudoaneurysm after blunt trauma in a hemodynamically stable patient . it was diagnosed with a venogram , determined to be non - enlarging and without extravasation , observed and surveyed with ct angiography .
we submit this case as a potential management option for hemodynamically stable patients with stable traumatic venous aneurysms .
abstractlimited evidence - based protocols exist regarding the management of venous pseudoaneurysms . 
 cases reports have documented surgical treatments including endovascular coil embolization or suture ligation in the setting of hemodynamic stability . depending on the location of the venous injury , a more conservative approach to a stable pseudoaneurysm may be advantageous . 
 this report describes a case of a patient who sustained a blunt traumatic common iliac vein pseudoaneurysm who was successfully managed non - operatively .