The intriguing problem of varicose veins.

New methods of investigation have given a fresh understanding of varicose veins. Aspects of this are described based on findings in patients investigated by Doppler flowmetry, functional phlebography and photoplethysmography. All observations refer to the upright position where various forms of failure in pumping blood upwards against gravity may arise. Simple varicose veins conduct flow from above a pumping mechanism to the low pressure area beneath it. Thus, saphenous incompetence allows downflow from the groin to below the musculovenous pumps of the calf and the foot. It is this reversed flow that creates tortuosity in the branch veins and sacculation beneath leaking saphenous valves. Perforator incompetence is often incidental and a concealed saphenous incompetence, without varicosites, is easily overlooked. Functional phlebography has shown that many patients with varicose veins also have inadequate deep vein valves so that the pumping mechanisms are soon overwhelmed and this may explain why some develop ulceration and others do not. Complex patterns of flow in superficial veins have been demonstrated, for example: strong collateral upflow past deformed deep veins whilst other veins allow spillage downwards: crossover incompetence with flow to the opposite limb and down its incompetent saphenous vein. The special investigations can accurately predict the outcome of surgery and are an important addition to successful management.