A key to understanding postoperative lymphoedema: a study on the evolution and consistency of oedema of the arm using ultrasound imaging

Post-mastectomy oedema is a very serious complication that, in the course of time, will transform into fibrotic tissue. The aim of our study is to evaluate when and in which layer liquid oedema transforms into fibrotic tissue. To do so, ultrasonographic images were taken of 22 patients and 9 control women at the shoulder and 10 cm proximal and distal from the olecranon, with the images then being scanned and imported into a computer program to determine echogenicity of the dermis, subcutis, subcutis on dermal side and subcutis on fascial side. Statistical analyses were performed by means of the Wilcoxon test and a Student's t-test. No significant differences (P< or =0.05) were found for the different parameters in the control group. In the experimental group: significant differences in perimeter, skinfold, thickness of dermis and subcutis were found. Although not significant, subcutaneous tissue was more echogenic on the oedematous side, with significant hyperechogenicity at the fascial subcutaneous layer. This indicates that fibrotic tissue develops distally in the forearm.