1st April 2022

A 62-year-old gentleman has been referred by his GP after developing a painful lesion on his right lateral malleolus

A 62-year-old gentleman has been referred by his GP after developing a painful lesion on his right lateral malleolus. He has experienced pain in both legs at rest. On examination his lower legs and feet are bilaterally pale, with a reduced hair distribution. There is a 3cm punched out, deep lesion on his right lateral malleolus. There is necrotic tissue present, but there are no overt signs of infection.

The patient has smoked 15 cigarettes a day for the last 43 years. His ankle brachial pressure index is 0.35 bilaterally. He has mild COPD, but is otherwise well. 

Given the most likely diagnosis what is the most appropriate first line investigation? 

Select the SINGLE most appropriate option from the list below. Select ONE option only.