A profile of lower-limb deep-vein thrombosis: the hidden menace of below-knee DVT.
OBJECTIVE
To describe the anatomical site and laterality of deep-vein thrombosis (DVT) in symptomatic patients using contrast venography (CV), and to assess age, sex distribution, and accuracy of pre-test clinical suspicion of DVT.


METHODS
One thousand, five hundred and seventy-two patients undergoing CV because of a clinical suspicion of DVT at a large teaching hospital from October 1995 to March 2003 were prospectively studied.


RESULTS
Thrombi were demonstrated in 511 (32.5%) of all CV studies. Isolated, below-knee thrombi were identified in 29.4% of positive studies. There was a left-sided predominance of DVT (ratio 1.24:1) that was most evident in the elderly and in more proximal veins.


CONCLUSIONS
Almost a third of positive cases were shown to be isolated, below-knee thrombi. These are thrombi that are more difficult to detect by non-invasive means. A left-sided predominance of DVT is evident.
Department of Clinical Radiology, Royal Infirmary of Edinburgh, Edinburgh, UK.
G W
GW
Cowell
J H
JH
Reid
A J
AJ
Simpson
J T
JT
Murchison
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007866:Leg / Q000098:blood supply* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010690:Phlebography / Q000379:methods; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012737:Sex Factors; D020246:Venous Thrombosis / Q000000981:diagnostic imaging*