Intravenous ultrasound (IVUS) is a combination of non-invasive ultrasound technology and invasive catheter technology, a medical imaging technology using a special catheter with an ultrasonic probe attached at the end.This allows ultrasound technology, such as piezoelectric conduction or ultrasound sensors, to be used to examine the lining of blood vessels.
This method can be used to accurately grasp the vascular wall morphology and stenosis degree, especially in the interventional diagnosis and treatment of coronary heart disease has a high guidance value.
Before IVUS was applied to the iliac vein, iliac venous obstructive lesions were easily ignored.At present, in vitro angiography, which is commonly used in hospitals, can only show the patency and return flow of femoral popliteal vein below the inguinal ligament, but cannot clearly show the iliac vein due to the interference of intestinal gas and the deep position of the vein.In order to understand the situation of iliac vein, most hospitals often use venography, CT venography, magnetic resonance imaging, etc. to understand the situation of iliac vein.However, conventional anteroposterior venography of the lower extremities is not good for the iliac vein.Sometimes a femoral venipuncture is used for an iliovenography, but the results are often hasty and vague.Unless there is an obvious obstructive structure, most of the imaging findings are in the general "iliac vein patency".Mri and CT resolution are also insufficient to understand all iliac venous lesions.At present, the most clear means of examination is intravascular ultrasound.Therefore, it is necessary to use IVUS to confirm the condition of iliac venous disease in patients with severe edema, venous dilatation and ulcer, even if the angiography and angiography show "unobstructed vessels".If the patient has a severe iliac venous lesion, there is a high rate of recurrence or inefficacy with a large saphenous vein operation alone.
Studies on IVUS have shown that obstruction components are common in thrombotic sequelae or non-thrombotic iliac venous lesions.In non-thrombotic iliac venous lesions, the site of obstruction is not as traditionally thought to occur only in the right iliac artery to cross the left iliac vein, but is also common in the inferior epigastric artery crossing site and behind the inguinal ligament.In patients with non-thrombotic iliac venous disease, where obstruction is a partial stenosis, a large number of collateral veins are not seen on the venography.This is very misleading to clinicians.
IVUS can clearly show the easily missed iliac vein obstruction lesions such as imaging and color doppler ultrasound.The removal of iliac vein obstruction by interventional stenting can effectively relieve CVI symptoms.
