Liquid Crystal Thermography and Duplex in the Preoperative Marking of Varicose Veins

Abstract

Objective:

To determine the role of liquid crystal thermography (LCT) in preoperative marking of varicose veins and incompetent perforating veins.

Design:

Single patient group study comparing techniques.

Setting:

Teaching hospital vascular laboratory.

Patients:

Two hundred patients (265 legs) referred to St Mary's Hospital Vascular Laboratory for preoperative varicose vein marking.

Methods:

Patients were studied using LCT and duplex ultrasonography to identify calf perforating veins.

Results:

In part I of the study LCT identified 47 ‘areas at risk’, 42 of which were demonstrated to contain incompetent perforating veins on duplex examination (positive predictive value 89%). Thirty-eight of these 42 patients were explored at operation and 36 (95%) were confirmed as incompetent. The remaining two perforating veins could not be located. In part II of the study LCT identified 327 ‘areas at risk’, 299 of which were demonstrated to contain incompetent perforating veins on duplex examination (positive predictive value 91%).

Conclusion:

LCT is useful in the identification of incompetent perforating veins, it is easy to perform, less time consuming, cheaper and can replace duplex scanning.