This patient presented with urinary retention and had a catheter inserted. This ultrasound image shows the catheter incorrectly sited in prostatic urethra.

By ensuring good technique for catheter insertion. The catheter should always be inserted up to the junction with the valve. Urine should drain. If it does not then it may not be sited correctly and may be coiled in the urethra. The balloon should not be inflated and the catheter manipulated into a better position. Aspiration of the catheter may help to clear any gel that may be occluding the tip.