Figure 14c. Distortion or obscuration of the bulbocavernosus muscle. (a) CT scan of a patient with a type III urethral injury shows a distorted contour of the bulbocavernosus muscle (arrowheads) with an obscured fat plane. Note the air in the urethra, which resulted from an unsuccessful attempt at catheterization. (b) CT scan of a patient with a type I urethral injury shows a slightly obscured bulbocavernosus muscle, which cannot be clearly identified around the bulb of the penis (b). Arrowheads = expected location of the bulbocavernosus muscle. (c) CT scan of another patient shows a fracture of the left ischiopubic ramus with preserved fat planes (arrowheads) and no hematoma of the ischiocavernosus (arrow) or bulbocavernosus muscle. The patient had no urethral injury.