femoral artery pseudoaneurysm following by cardiac catheterization is a serious groin complication requiring careful assessment and prompt intervention . risk of femoral artery pseudoaneurysm is estimated at 0.6 to 17 following diagnostic and interventional procedures . the clinical usage of bedside ultrasonography as part of the physical examination by attending emergency physicians has increased significantly over recent years . bedside emergency department ultrasonography provides the clinician with critical information noninvasively , rapidly determining various anatomical structures . we presented the case of a femoral artery pseudoaneurysm detected by the bedside emergency department ultrasonography secondary to angiographic catheterization . a 51-year - old woman presented to the emergency department ( ed ) with a 2-day history of right groin pain , discoloration and swelling of the inguinal area . six days before presentation , diagnostic angiographic catheterization was performed in her right femoral area . on physical examination , emergency department ultrasonography ( us ) performed at the bedside revealed a pulsating anechoic lesion communicating with the superficial femoral artery by using a 10-mhz linear probe ( fig .  1 ) . doppler examination of the patient showed a 31    26-mm pseudoaneurysm in direct continuity with the right femoral artery ( fig . she was surgically treated and discharged from the hospital fully recovered 10 days later . 2a and b : duplex doppler us image depicts a 31    26-mm pseudoaneurysm ( psa ) with bidirectional flow within the neck pseudoaneurysm of the superficial femoral artery . there is an anechoic lesion communicating with the right superficial femoral artery a and b : duplex doppler us image depicts a 31    26-mm pseudoaneurysm ( psa ) with bidirectional flow within the neck a painful mass in the femoral area should heighten the clinician s index of suspicion for a possible pseudoaneurysm . differential diagnoses of pseudoaneurysm include abscess and hematoma formation , cyst , malignant mesenchymal tumor and lymphadenopathy , which may be the landmark of sexually transmitted infections such as lymphogranuloma venereum , gonorrhea or cancers such as lymphoma . the diagnosis of a femoral pseudoaneurysm may be performed with invasive and noninvasive methods : color doppler us , ct angiography , magnetic resonance angiography and conventional angiography . all of these conditions may be evaluated with bedside ed us . using b - mode imaging , a pseudoaneurysm will usually appear as an anechoic lesion communicating with the femoral artery in the femoral area ; this mode is useful for measuring pseudoaneurysm size and compression of adjacent structures . other advantages of ed us examination are that it is a simple , rapid , inexpensive and useful method for evaluating pseudoaneurysyms . duplex ultrasound is the diagnostic test of choice and demonstrates a high velocity jet through a defect in the arterial wall on color flow imaging . , us examination may be a valuable tool in the ed to perform the differential diagnosis of a superficial femoral pseudoaneurysm .