Urinary catheter

A urinary catheter comprising:

• (a) a tube, the tube having (i) a wall with an outer surface, the outer surface having a first cross-sectional area, (ii) a lumen, (iii) a distal end with one or more openings in communication with the lumen, and (iv) a proximal end with an opening in communication with the lumen;
• (b) a valve that is operated to be in (i) a closed configuration, wherein fluid does not flow out of the proximal end, or (ii) an open configuration in which fluid does flow out of the proximal end;
• and
• (c) a retainer portion between the distal end and the proximal end, wherein the retainer portion has (i) an outer wall that has an outer surface and an inner surface, (ii) a cavity inside of the outer wall, (iii) a core inside of the cavity, the core having a passage in which the tube is positioned, and (iv) at least one expansion structure positioned inside of the cavity, wherein the at least one expansion structure has a first end connected to the core, a second end in contact with the inner surface of the outer wall of the retainer portion, and an intermediate section between the first end and the second end and in contact with the inner surface of the outer wall of the retainer portion so as to apply outward pressure to the outer wall, wherein the intermediate section and the outer wall are configured to be compressed to a compressed position when compressive force is applied by a wall of a penile urethral, and when in the compressed position are configured to fit through the penile urethra, and the intermediate section and outer wall are configured to expand to an expanded position when compressive force is not applied by the wall of the penile urethra, and when in the expanded position the outer wall has a diameter that is at least twice as its diameter when positioned in the penile urethra.