Role of radioisotopic lymphoscintigraphy in postphlebitic syndrome of the legs

: Post-phlebitis syndrome of the lower limbs is a set of symptoms that follow a state of phlebostasis and phlebolymphostasis with consequent oedema and tissue distress. We submitted 36 patients with post-phlebitis syndrome of the lower limbs to radioisotopic lymphoscintigraphy for the purposes of evaluating the vicariant function of the lymphatic system and the possible role of the lymphatic system in the genesis of dermo-epidermal abnormalities. The average age of the patients was 53.2 years (range: 43-69 years; M:F ratio: 0.50). The control group consisted of 6 healthy subjects. The average duration of the post-phlebitis syndrome in the patients studied was 8.5 years. We excluded from the study patients in whom a central cause was identified as being responsible for the pathogenisis of the oedema of the lower limbs. In addition, patients with obliterant arteriopathy were also excluded. Venous pathology was evaluated first clinically and then investigated by continuous-wave Doppler. As a first step, venous pressure was measured by Doppler phlebomanometry in clino- and orthostatism. All patients underwent radioisotopic lymphoscintigraphy with microcolloids using the Rijke technique. Radioactivity was monitored by means of a computerized gamma-camera. We classified the pathological findings of radioisotopic lymphoscintigraphy as follows: 1) delayed transit; 2) obstacles; 3) star-shaped superficial collateral lymphatic circulations; 4) lymphocoele or cutaneous lakes. A significant difference was detected (p < 0.05) between the pressure values in the post- phlebitis lower limbs and the pressure values in normal subjects. Combining the results of our measurements we recorded delayed transit in 5 patients (69.5%). This latter group included the cases with the severest forms of post-phlebitis syndrome. Therefore, better knowledge of the pathophysiology of the lymphatic system would appear to be useful in order to understand the origin and evolution of oedema of the lower limbs of patients with post-phlebitis syndrome. To this end, radioisotopic lymphoscintigraphy may be useful as a first-level examination in order to evaluate the capacity and efficiency of the lymphatic system.