Active (systolic) reflux demonstrated in a below-knee isolated incompetent perforating vein associated with a symptomatic varicose vein using infrared thermography, illustrated by a case report.

Background:The role of incompetent perforating veins (IPVs) in lower limb varicose veins is controversial. There are different views on the mechanism of “incompetence” and, hence, the importance of IPVs. Those following CHIVA and “haemodynamic surgery” principles suggest that higher velocities in the deep veins cause blood to flow inwards due to the Venturi effect. The senior author of this case has previously proposed that increased pressure by muscle activity forces blood out of any IPV – called “active” reflux. This case report appears to show active reflux in an isolated IPV using infrared thermography. Methods: A 34-year-old lady presented with a tender lower leg varicose due to an isolated IPV. She was placed supine and still for 10 minutes, then performed 10 plantar- and dorsi-flexions. Next, she stood up and stood still for 10 minutes. Her leg was monitored throughout using an infra-red camera (IFC).Results: Immediately on lying, the IFC showed the vein, indicating blood flowing out of the IPV from the warm deep compartment into the colder superficial compartment. Over 10 minutes, the signal reduced significantly, suggesting no more blood was being pumped out through the IPV. During 10 plantar- and dorsi-flexions, the signal returned strongly, indicating blood being pumped out of the IPV once again. On standing, the signal was strong initially, but after 10 minutes of standing still, the signal had faded, indicating a lack of passive (gravitational) reflux in the IPV.Conclusion: This case suggests that reflux through this IPV is due to muscle activity and not by passive reflux due to gravity. This could explain why IPVs can cause fasciocutaneous damage and/or varicose veins in the lower limb. If correct, failure to identify and treat IPVs during varicose vein surgery would mean that the procedure would be inadequate.