Leriche syndrome is chronic atherosclerotic occlusion of the distal abdominal aorta and/or both common iliac arteries. Classic triad: (1) bilateral lower extremity claudication (buttock, thigh, calf), (2) erectile dysfunction, and (3) absent or diminished bilateral femoral pulses. First described in 1940 by René Leriche. Prevalence is 0.6-1%, 3-5 times more common in males, and typically develops in 40-60 year old smokers with hypertension, diabetes, and hyperlipidemia. Due to the chronic progressive nature, extensive collateral vessel networks develop (internal iliac, lumbar, inferior mesenteric artery and profunda femoris anastomoses) and some patients may be relatively compensated. CT angiography (CTA) is the gold standard — demonstrating the level and extent of aortoiliac occlusion, collateral vessel anatomy, and distal runoff. Treatment options include aortobifemoral bypass (surgical gold standard), endovascular recanalization (PTA/stent), and medical optimization.
Age Range
40-75
Peak Age
60
Gender
Male predominant
Prevalence
Uncommon
Leriche syndrome develops as atherosclerotic plaque accumulation leads to progressive luminal narrowing and eventual complete occlusion at the aortic bifurcation and iliac arteries. The aortic bifurcation is particularly susceptible to atherosclerosis because blood flow in this region creates turbulence, low wall shear stress, and stasis zones — these hemodynamic conditions trigger endothelial dysfunction and accelerate plaque formation. Plaque progression spans years to decades: intimal thickening → lipid accumulation → fibrous cap formation → calcification → luminal narrowing → thrombotic occlusion. In chronic occlusion, compensatory mechanisms activate — collateral vessel networks develop: internal iliac arteries → iliolumbar and lateral sacral branches → gluteal and obturator arteries → profunda femoris → lower extremity; IMA → arc of Riolan → SMA; lumbar arteries → gluteal anastomoses. On CTA, this collateral network appears as prominently dilated tortuous vessels because chronic increased flow increases vessel diameter (flow-mediated vasodilation). No enhancement in the occluded aortoiliac segment — contrast does not pass because the lumen is completely filled with thrombus. Calcified atherosclerotic plaques appear as high-density wall calcification (100-1000+ HU) on CT.
Abrupt termination of the contrast-filled patent aortic lumen with a concave meniscus shape at the aortic bifurcation level on CTA — the upper surface of the thrombus appears with a concave contour at the occlusion point. This is the most characteristic CTA sign of complete aortoiliac occlusion and clearly localizes the occlusion level.
Absent enhancement in the distal abdominal aorta and/or bilateral common iliac arteries on CTA — lumen completely filled with low-density thrombus. Occlusion typically begins from the infrarenal aorta and extends to both common iliac arteries. Extensive calcified atherosclerotic plaque accompanies in the aortic wall. Renal arteries are generally patent with normal enhancement (occlusion below renal artery origin). MIP and volume rendering reconstructions best demonstrate the level and extent of occlusion.
Report Sentence
Complete occlusion of the distal abdominal aorta and bilateral common iliac arteries, consistent with Leriche syndrome; renal arteries are patent.
Extensive collateral vessel network on CTA: (1) internal iliac → iliolumbar and lateral sacral → gluteal region, (2) lumbar arteries → gluteal anastomoses → profunda femoris, (3) IMA → marginal artery → arc of Riolan → SMA (visceral collateral), (4) epigastric arteries → anterior abdominal wall. These collateral vessels appear prominently dilated, tortuous, and contrast-filled. Collateral extent reflects chronicity of occlusion — in acute occlusion, collateral development is insufficient.
Report Sentence
Extensive collateral vessel network development via internal iliac, lumbar, and IMA-SMA collateral pathways secondary to aortoiliac occlusion.
Flow signal absence (flow void) in the distal abdominal aorta and iliac arteries on MRA. On contrast-enhanced MRA (gadolinium), no enhancement in the occluded segment — proximal patent aorta enhances while signal disappears at occlusion point. On TOF MRA, flow signal absence indicates occlusion. MRA is used in addition to CTA or as alternative in patients with renal dysfunction and iodinated contrast contraindication.
Report Sentence
Flow signal absence in distal abdominal aorta and bilateral iliac arteries on MRA, consistent with chronic aortoiliac occlusion (Leriche syndrome).
Normal triphasic flow pattern in bilateral femoral arteries is lost on duplex Doppler US. Monophasic, low-amplitude (parvus et tardus) flow pattern or complete flow absence is seen distal to occlusion. Flow velocities obtained from femoral arteries are markedly reduced. ABI (ankle-brachial index) measurement <0.4 supports severe peripheral arterial disease. US is used for initial evaluation but CTA is needed for occlusion level and collateral anatomy.
Report Sentence
Normal triphasic flow pattern in bilateral femoral arteries is lost with monophasic parvus et tardus pattern, consistent with aortoiliac occlusion.
Assessment of arterial status distal to the occlusion (external iliac, femoral, popliteal, tibial) on CTA is critical for surgical planning. 'Distal runoff' adequacy — presence of suitable target vessel for reconstruction — determines bypass success. Patency of profunda femoris and superficial femoral artery filling via collaterals, popliteal and tibial artery status should be assessed in detail. TASC II classification (A-D) guides treatment strategy based on lesion extent.
Report Sentence
Bilateral profunda femoris and superficial femoral arteries filling via collaterals distal to aortoiliac occlusion are patent, suitable distal target vessel available for surgical reconstruction.
Extensive calcified atherosclerotic plaque in the distal abdominal aorta and bilateral iliac arteries on non-contrast CT. Calcification may be intimal (irregular, punctate) or medial (linear, tram-track pattern). Calcification extent reflects chronicity and severity of atherosclerotic disease. Calcification mapping is critical for endovascular planning — extensive calcification may complicate stent placement.
Report Sentence
Extensive calcified atherosclerotic plaque in the distal abdominal aorta and bilateral iliac arteries, consistent with chronic aortoiliac occlusive disease.
Criteria
Unilateral or bilateral common iliac artery stenosis, short (<3 cm) unilateral iliac occlusion.
Distinct Features
Endovascular treatment (PTA/stent) first choice. High success rate.
Criteria
Infra-renal aortoiliac occlusion, diffuse bilateral iliac disease, iliac occlusion + femoral disease, or unilateral iliac occlusion + contralateral stenosis.
Distinct Features
Aortobifemoral bypass surgical gold standard. Endovascular approach has limited success but attempted in high-risk patients. 5-year graft patency 85-90%.
Criteria
Sudden bilateral lower extremity ischemia — 6P (pain, pallor, pulselessness, paresthesia, paralysis, poikilothermia). In setting of atrial fibrillation or cardiac thrombus.
Distinct Features
No collateral development (acute event). 'Saddle'-shaped thrombus sitting at aortic bifurcation on CTA. Requires emergent thrombectomy or thrombolysis. Mortality around 50%.
Distinguishing Feature
In dissection, intimal flap and dual lumen (true + false) are seen; in Leriche, occlusion and calcified atherosclerosis predominate, no intimal flap.
Distinguishing Feature
In Takayasu, young female, wall thickening (concentric) and stenosis predominate; in Leriche, older male, calcified atherosclerosis and occlusion. Takayasu also involves aortic arch branches.
Distinguishing Feature
In AAA, aortic dilatation (>3 cm) predominates while in Leriche, occlusion predominates. Both may coexist (aneurysm + thrombotic occlusion).
Distinguishing Feature
FMD in young women, string-of-beads appearance with iliac/renal artery stenoses; Leriche in older men with extensive calcified atherosclerosis and occlusion.
Urgency
urgentManagement
surgicalBiopsy
Not NeededFollow-up
6-monthLeriche syndrome treatment is planned according to symptom severity and TASC classification. Aortobifemoral bypass is the gold standard for TASC D lesions (85-90% five-year graft patency). In high surgical risk patients, axillofemoral bypass or endovascular recanalization (hybrid approach — aortic stent + iliac PTA) may be attempted. Medical optimization is mandatory in all patients: smoking cessation, statin, antiplatelet (aspirin ± clopidogrel), blood pressure and diabetes control, exercise rehabilitation. In critical limb ischemia (rest pain, trophic changes, gangrene), emergent revascularization is required. Follow-up: CTA or Doppler US every 6-12 months for graft/stent patency and distal perfusion assessment.
Treatment of Leriche syndrome is aortobifemoral bypass (surgical gold standard) or endovascular recanalization. TASC II classification guides treatment decisions. Intervention is preferred before development of critical limb ischemia. Concomitant coronary and carotid disease should be assessed.