Diagnosis of deep vein thrombosis by Duplex Doppler ultrasound imaging at the Singapore General Hospital.

Deep vein thrombosis (DVT) of the lower extremity is the major cause of pulmonary embolism and chronic venous obstruction disease of the legs. However, the clinical diagnosis of leg vein thrombosis is notoriously difficult. Venography, using iodine containing contrast materials, has been the most reliable older method for diagnosing thrombosis. It is relatively more invasive, requires exposure to radiation and is not free of risks. Doppler ultrasonography has been shown to be highly sensitive and specific in the diagnosis of obstruction of flow in veins. We present 25 patients studied at Singapore General Hospital (SGH) with Doppler for the presumptive clinical diagnosis of DVT. Thirteen were found to have complete or partial obstruction of leg veins and 12 showed normal veins. These 12 patients were thus spared the risk and expense of long term anticoagulation. In experienced hands, Duplex Doppler ultrasonograph is an excellent diagnostic modality for the diagnosis or exclusion of significant deep vein thrombosis of the legs. It can be carried out safely and reliably in the very sick, in patients with renal failure, diabetics and the pregnant.