CT venography delivers roadmap for surgical planning
Chronic venous disease of the legs is one of the most common conditions affecting people of all races; according to the Society of Interventional Radiology, approximately half of the U.S. population has venous disease--50 to 55 percent of women and 40 to 45 percent of men. And of these, 20 to 25 percent of the women and 10 to 15 percent of men will have visible varicose veins.

Because of the ability to evaluate hemodynamic information and its convenience and availability, duplex sonography is considered the reference standard for noninvasive anatomic and functional assessment of venous reflux. However, ultrasound is limited in its assessment of varicose veins, because of its limited field of view. As such, deep-seated varicose vein pathways and major perforators can be missed.

Three-dimensional CT scans provide a comprehensive view of complex varicose veins in the lower extremities, according to a study performed at the Seoul National University Hospital in Seoul, South Korea, and published this month in the American Journal of Roentgenology. In addition, this technique aids surgeons to more effectively treat varicose veins.

Researchers in the departments of radiology and general surgery conducted CT scans on 100 consecutive patients who referred for evaluation of varicose veins over a three-month period. Exams were performed on a GE Healthcare 8-slice LightSpeed Ultra or on a 16-slice Siemens Medical Solutions Sensation 16 CT system using a non-ionic contrast agent (Ultravist 370, Bayer Healthcare).

Thin-section axial images were reformatted on a workstation running Infinitt’s Rapida 3D reconstruction software and evaluated by two experienced radiologists.

“To evaluate the saphenofemoral and saphenopopliteal junctions, we used axial images and maximum intensity projection and multiplanar reformatted images in the interactive image plane,” the authors wrote.

The images were evaluated for overall image quality and then analyzed for factors believed to affect image quality. The researchers reported that the quality of the 3D images was excellent in 76 cases, fair in 21 and poor in three.

The 3D CT scans also gave the physicians a closer look at the great saphenous vein in 99.5 percent of all lower extremities being examined.

“Contrast-enhanced CT venography can show the calf veins with clear anatomic landmarks such as muscle and bone, and use of this technique facilitates detection of abnormalities of the deep calf veins,” they noted.

The 3D images from the study provided surgeons a more comprehensive way to see the disease, allowing them to better plan their surgery to prevent recurrence of varicose veins, according to the researchers.

The combination of anatomic information available from 3D CT scans and functional information available from Doppler sonography are complementary in evaluating varicose veins, the authors noted, as the detection of perforators veins with 3D CT can yield better surgical outcomes for patients.