DIGITAL PHOTOPLETHYSMOGRAPHY AND LIGHT-REFLECTION RHEOGRAPHY - A CLINICAL COMPARISON

BACKGROUND. Light reflection rheography (LRR) is appropriate for the g lobal assessment of calf-pump insufficiency regardless of whether it i s caused by varicosity, the post-phlebitic syndrome, or deep venous th rombosis. The instrument has been increasingly used by many phlebologi sts. Digital photoplethysmography (D-PPG) is a further development of this well-established LRR. With this D-PPG instrument it is possible, in contrast to LRR, to calibrate the reflected light. OBJECTIVE AND ME THODS. To compare the venous refilling times of both the LRR and the D -PPG when measured at the same time on the same leg. We also evaluated the practical use of both instruments. In total we performed 152 simu ltaneous measurements with both instruments. RESULTs. We found a stati stically significant correlation when we compared the venous refilling time of both LRR and D-PPG (r = .664; P <.001). The observed agreemen t between both instruments for detecting a disturbed venous refilling time (less-than-or-equal-to 25 seconds) is 92%. CONCLUSION. Both instr uments seems to correlate as has been shown in this and other studies. The D-PPG has the advantage of being more handy. Futhermore the refle cted light is calibrated, which enables to compare intra- and interind ividual measurements.