Usefulness of the computed tomography venography for evaluation of leg edema including deep vein thrombosis in rehabilitation patients

Abstract

Objective: To investigate the usefulness of computed tomography venography (CTV) for evaluation of leg swelling, especially deep vein thrombosis (DVT), in rehabilitation patients.

Methods: A hundred twenty-three patients, who had performed CTV performed because of suspected DVT in our clinic, were enrolled. We performed chart reviews retrospectively and categorized CTV findings as follows: DVT distal to inguinal ligament and no compression lesion; DVT proximal to inguinal ligament and no compression lesion; DVT distal to inguinal ligament and anatomical variant (for example, May-Thurner syndrome); DVT due to compression of mass (cancer or cyst); DVT and other incidental abnormal finding; and no DVT and other possible causes of leg swelling.

Results: DVTs were found in 65 (53%) patients. DVTs were found at distal level (thigh or lower leg) to inguinal ligament in 47 patients. DVTs were found at proximal to inguinal ligament, usually undetectable with duplex ultrasonography, in 6 patients. DVTs caused by external compression, such as femoral vein and cancer mass, were found in 12 patients (10%), which are also not easily detected with duplex ultrasonography. Other various causes of leg edema without DVT were found in 22 (18%) patients.

Conclusion: CTV can evaluate more extensively venous problems in the pelvis and abdomen and detect other possible causes of leg swelling. Therefore, CTV can be a useful tool not only for easy detection of DVT but also for evaluating differential diagnosis of leg edema in rehabilitation patients.

Keywords: Computed tomography; Edema; Venography; Venous thrombosis.

Fig. 1

The computed tomography venography reveals low signal intensity lesion, which means deep vein thrombosis (DVT), inside of right iliac vein (arrowhead) (A) and the well enhancing mass lesions at right lower abdomen (white arrow) compress right external iliac vein (arrowhead) proximal to DVT lesion (B).

Fig. 2

This image shows low density 2.8×2.9×2.1 cm sized mass lesion (white arrow) in posterolateral area to right common femoral vein (arrowhead) in axial view (A) and the mass (white arrow) compresses right common femoral vein (arrowhead) in coronal view (B).

Fig. 3

The graph shows distributions of risk factors of VTE among four groups: DVT (+) distal, DVT distal to inguinal ligament; DVT (+) proximal, DVT proximal to inguinal ligament (in abdomen/pelvis) or with compression of other structures; DVT (-), no DVT detected; and DVT (-) other causes, no DVT and other causes of leg swelling detected). The relative proportion of LE paralysis in DVT (-) and DVT (-) with other cause groups was higher, similar to DVT (+) group. Therefore in the patients with LE paralysis usually present in the department of rehabilitation there are various causes of leg swelling and some causes can be found more easily by computed tomography venography than other study. DTV, deep vein thrombosis; VTE, venous thromboembolism; LE, lower extremity.

Fig. 4

This graph shows the D-dimer values of four groups. D-dimer values of deep vein thrombosis (DVT) proximal group (groups 2, 3, and 4) were significantly different from those of the other three groups. ^*p<0.05, result from ANOVA with post-hoc analysis.