Normal Seminal Vesicles. Transrectal US image shows the normal hypoechoic convoluted tubular appearance of the seminal vesicle (arrow). B, bladder.

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Prostate Anatomy. Transrectal US images of the prostate are routinely viewed inverted. The transducer is at the bottom rather than the top of the image. This sagittal image shows the normal peripheral zone (arrow) to be slightly echogenic compared to the hypoechoic, more heterogeneous central gland (G).

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