A radioisotopic method was used to evaluate the state and dynamics of the lymphatic system in 92 patients affected by chronic oedema of the limbs and in 12 control subjects. After interstitial injections of 99mTc-sulphur microcolloid, scans were obtained using a LFOV camera linked to a data processor. The quantitative indices of clearance and lymph node uptake obtained showed good correlation with lymphoedema etiology, controls and ostensibly healthy limbs of patients affected by monolateral disease. In conclusion, quantitative lymphoscintigraphy appears to be a feasible indicator of early changes in the lymph pathophysiology and supports the hypothesis that lymphoedema generally arises from a predisposing congenital pathology.