Alternatively, if the ultrasound is inconclusive, a more invasive venography procedure can be performed.
当超声无法做出诊断时,也可以采用静脉血管造影这种有创的检查方法。
英语百科
Venography
Venography (also called phlebography or ascending phlebography) is a procedure in which an x-ray of the veins, a venogram, is taken after a special dye is injected into the bone marrow or veins. The dye has to be injected constantly via a catheter, making it an invasive procedure. Normally the catheter is inserted by the groin and moved to the appropriate site by navigating through the vascular system.