Non-invasive investigation of lower limb revascularisation using resting thallium peripheral perfusion imaging

Resting thallium thigh and calf imaging was performed in 11 patients with lower limb ischaemia before and after revascularisation. Eight patients had successful revascularisation but in the other three the procedure failed to improve the circulation. Despite symptomatic improvement and increases in ankle systolic pressures after successful revascularisation there was no change in thallium uptake. Thallium imaging was compared with radionuclide angiography and blood pool imaging in six patients. Radionuclide angiograms confirmed the presence of well developed collateral circulation in some patients with increased thallium uptake in the symptomatic limb and in all cases the angiograms were clinically useful. There was no correlation between thallium and blood pool images. Resting lower limb blood flow did not change after revascularisation and thallium peripheral perfusion imaging did not aid the assessment of the response to lower limb revascularisation.