Improvement of a three-dimensional measurement system for the evaluation of foot edema

Background/aims: This study investigated the accuracy and usefulness of a newly improved three‐dimensional measurement system for measuring the volume and circumference at the foot as well as at the calf and ankle. Methods: Regarding the newly improved device, halogen light was projected from four directions instead of the conventional two directions. The circumference and volume were measured in the morning and evening with and without elastic stockings in 23 healthy subjects. Results: The average circumference at the foot calculated using the ‘average method’, in which the circumference of the foot was measured in 10 places every 1 mm and the values were averaged, significantly increased in the evening compared with in the morning. When stockings were applied, the significant differences in the circumference or volume between the morning and evening disappeared at all sites of the leg. Conclusion: The newly improved three‐dimensional measurement system incorporating the halogen light from four directions, in which the foot circumference was calculated using an ‘average method’, was reliable and useful for evaluating edema at the foot as well as at the calf and ankle. The beneficial effect of elastic stockings on edema prevention was observed at all sites of the leg.