Tkrik, I completely agree with Cricket. It is not painful. They insert a cath to infuse the saline, and small electrodes are placed in your rectum and bladder(tiny little wires). Electrodes are how they record the pressure in your bladder while filling, and the ammount of pressure you excert to urinate(when your bladder reaches a "gotta go now feeling").Other important information is how much your bladder can hold.

Relax, and it is a breeze. You will have a nurse and doctor, in my case, while you void.They are busy reading the data recorded from your electrodes.Just remember they are collecting scientific data on you, that can answer lots of questions about the kind of neurogenic bladder you may have.

Never heard of any kind of implantatin during this test.