Misplaced Foley in the prostatic urethra
In this ultrasound image of long axis of the urinary bladder, Foley balloon (green arrow) is in the prostatic urethra resulting in urinary retention. Note the anechoic urine-filled bladder and prostate gland surrounding the balloon. This can be quite painful, but as most of our ICU patients are sedated, it might go unnoticed.
Here is another example: