Ultrasonography is not the only way to diagnose DVT

Patients with abnormal results on d-dimer testing and a low clinical probability of deep venous thrombosis (DVT) do not need ultrasonography to exclude the diagnosis. Reviewing 12 studies including 5431 patients, Fancher and colleagues (p 821) found that normal results from a less sensitive d-dimer test would exclude the likelihood of DVT in 99.5% of patients with a low clinical probability of DVT, and a normal highly sensitive d-dimer test would exclude the diagnosis among all patients at low or moderate risk. These patients would not require additional tests, say the authors.

Credit: JAMES KING-HOLMES/SPL