Differences in Venous Function of the Lower Limb by Time of Day: A Comparison of Chronic Venous Insufficiency between an Afternoon and a Morning Appointment by Duplex Ultrasound

Abstract

Objective To determine the importance of the time of the day in relation to the accuracy of duplex ultrasound studies of lower limb chronic venous insufficiency (CVI). Method Using duplex ultrasound techniques, 40 participants (48 limbs), which included 26 women and 14 men ranging from 24 to 76 years of age, were recruited. All participants tested positive to primary CVI in a 4- to 6-pm afternoon timeslot and returned the next morning between 8- and 9-am for a follow-up retest of their incompetent vein sites. Results A total of 32.5% (13) of participants or 29.2% (14) of limbs demonstrated a degree of change in results from incompetence in the afternoon to competent the next morning. Most significant were the perforator veins; 38% of those tested showed a change of results, followed by a 9% change in the short saphenous veins, a 2% change in the long saphenous veins, and no change was demonstrated from the alternative superficial vein pathways or the saphenofemoral/popliteal junctions. Conclusion Venous function can change from an afternoon to the next morning. The extent of venous incompetence is better diagnosed in the late afternoon, with the perforator veins most susceptible to a change of competence.