Definition of May Thurner syndrome
May-Thurner syndrome is a condition in which iliofemoral deep venous thrombosis (DVT) are developed. This is obtained due to anatomical abnormality causes the right common iliac artery lies on the upper surface and constricting the left common iliac vein against the lumbar spine. In May-Thurner syndrome, blood circulation is interrupted due to large clot is formed in the left leg. May-Thurner syndrome is an inherited congenital disorder. May-Thurner syndrome has been rarely developed. [1,2]
Only 20% population has developed May-Thurner syndrome. The incidence rate almost three times greater in female than male. The condition is more common in young aged female (age between 20 to 50 years).[1,3]
The name of the syndrome is based on physicians R. May and J. Thurner, the first describers of this condition in 1957. The condition is also termed as “iliac compression syndrome”. [1,4]
The symptomatic approach of May-Thurner syndrome depends upon the compression of the left common iliac vein. May-Thurner syndrome is asymptomatic in mild to moderate narrowing of the left common iliac vein. In severe narrowing of the due to harder compression provide following symptoms:
- Leg swelling and pain
- Numbness in the leg
- Pain in the thigh or hip
- Burning pain in the foot altogether termed as chronic venous insufficiency
- Lumbar back pain
- Blood clots
- Deep vein thrombosis in the pelvic area
Sometimes, severe narrowing of the due to harder compression may not provide above mentioned symptoms due to adjacent smaller veins can bypass the narrowed area to widen the diameter of the affected vein and very efficiently draw off the blood from the leg vein. [1,3,4]
In normal anatomical feature can be explained as the blood collected from the lower limbs and the pelvis is collected in the inferior vena cava and then reach to the heart. The normal positioning of the right common iliac artery lies on top of the left common iliac vein.
In some individual, this close association generates pressure of the artery onto the vein, so that the vein is compressed between the artery in front and the lumber vertebra behind it. The resultant of this causes varying degrees of narrowing of the vein and that causes scarring of the affected vein.
This condition is clinically termed as “May Thurner syndrome”. Moreover, May Thurner syndrome is not a disease, but considered as a congenital anatomic variant. [2,3,4,5]
- History of oral contraceptive use
- Recent pregnancy. It has been observed that during pregnancy more DVTs particularly occur in the left leg than in the right.
- Recent prolonged travel 
Diagnosis of May Thurner syndrome
The following diagnostic tests are performed in suspected cases of May Thurner syndrome:
- Contrast venography
- Intravascular ultrasound
- Magnetic resonance imaging (MRI)
- Computed tomography (CT) scans
- Venogram or phlebogram [1,2]
Medication: long-term anticoagulation therapy require to prevent Deep Vein Thrombosis.
This is a minimal invasive procedure for inserting a stent to affected vein for holding the vein open and alleviate the blockage in the vein.
This is an open surgical procedure, in which blood flow is deflected around the narrowed portion of the vein through a bypass fixation.
Rearranging the right common iliac artery
The surgical relocation of the right common illiac artery is positioned at the rear side of the left common iliac vein, so the artery cannot generate pressure on the vein.
Constructing a tissue “sling”
Surgical intervention has made for placing a tissue in between the left common iliac vein and the right common iliac artery to raise the position of the artery, so it cannot create pressure on the vein.
Removal of blood clots
Medication and also medical device are available for breaking of the blood clot. This option is applied when the major blood clots present in the vein of the pelvis and causes severe inflammation of the leg. Surgical intervention or stent placement is only performed after the removal of the clot. [1,3,4]
Failure to correct the anatomic abnormality associated with May-Thurner syndrome can lead to recurrence of the Deep vein thrombosis and following additional complications may arise:
- Pulmonary emboli
- Chronic venous stasis
- Iliac vein rupture 
- Matthew Peters, Rashad Khazi Syed, Morgan Katz, John Moscona, Christopher Press, Vikram Nijjar, Mohannad Bisharat, Drew Baldwin; May-Thurner syndrome: a not so uncommon cause of a common condition; Proc (Bayl Univ Med Cent) 2012 July; 25(3): 231–233. Retrieve from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3377287/
- May-Thurner Syndrome; Heart and Vascular Center; University of Virginia Health System; Retrieve from: https://heart.uvahealth.com/services/compression-disorders/may-thurner-syndrome
- May-Thurner Syndrome (MTS) Overview
(Iliac Vein Compression Syndrome); ClotCare Online Resources; Retrieve from: http://www.clotcare.com/may_thurner_blood_clots.aspx
- May-Thurner Syndrome; Patient Education Blog; Retrieve from: http://patientblog.clotconnect.org/2011/01/10/may-thurner-syndrome/
- May-Thurner Syndrome (MTS); Retrieve from: http://my.clevelandclinic.org/services/heart/disorders/arterial-and-vascular-disease/may-thurner-syndrome