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Chapter 13
Duplex assessment of deep venous thrombosis and upper limb venous disorders
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CHAPTER CONTENTS
Introduction 189
Epidemiology and pathology of DVT 189
Signs, symptoms and treatment of DVT 190
Investigations for diagnosing DVT 191
Practical considerations for duplex assessment of DVT 192
Deep vein examination for acute DVT 192 Scan appearances for the assessment of acute
DVT 195
B-mode images 195 Color flow images 196 Spectral Doppler 197 Diagnostic problems 197
Accuracy of duplex scanning for the detection of DVT 198
Natural history of DVT 198
Recurrent thrombosis 199
Other pathologic conditions that can mimic DVT 199
Thrombophlebitis 200 Hematoma 200 Lymphedema 200 Cellulitis 201
Edema 201
Baker’s cysts 201
Enlarged lymph nodes 202 Other pathologic lesions 202
Upper limb veins 202
Anatomy of the deep upper limb veins 202 Anatomy of the superficial upper limb
veins 203
Thrombosis of the upper limbs 203
Technique for assessing the brachial, axillary and subclavian veins 204
Other upper limb venous disorders 204
Reporting 205
INTRODUCTION
Deep venous thrombosis (DVT) is a common dis- order that can lead to fatal pulmonary embolism (PE). Duplex scanning is considered to be the method of choice for the imaging of DVT, with venography reserved for technically incomplete or difficult duplex examinations. Duplex scanning can be used for serial investigations to monitor the progression and outcome of thrombosis. In addi- tion, duplex scanning can be useful for assessing the long-term damage to veins and valve function as a result of chronic post-thrombotic syndrome (Haenen et al 2002). This can lead to the develop- ment of lower limb venous hypertension and pos- sible leg ulceration. This chapter provides a description of duplex scanning techniques for the diagnosis of DVT and also considers other patho- logic conditions that may mimic the symptoms of venous thrombosis.
EPIDEMIOLOGY AND PATHOLOGY OF DVT
DVT usually affects the lower limb veins, but it can also occur in the upper limbs, especially in conjunc- tion with catheter access or malignancy. The pub- lished data on the epidemiology of DVT and PE demonstrate some variability, and reported rates of DVT and thromboembolism appear to be partly dependent upon methods of data collection (autopsy records, discharge diagnoses, and so forth) and the patient population studied. A recent systematic review by Fowkes et al (2003) indicated an incidence of DVT in the whole general population of approxi- mately 5 per 10000 per annum. However, the