Figure 2: Elastography of benign prostatic hyperplasia (stiff lesion). (a) No obvious lesion was found in the peripheral zone of the prostate by TRUS (right image), but a local blue area appeared in the right peripheral zone of the prostate by TRTE (left image, white arrow). (b) The section stained with picric acid-sirius red showed that Col1 and Col3 were cross-linked in distribution. The collagen volume fraction of Col1 (0.04) was greater than that of Col3 (0.01). TRTE: Transrectal Real-Time Tissue Elastography; TRUS: Transrectal Ultrasonography.