You need this basic info to consider this option.

Let's start this section off with a cautionary statement about catheters. We, as non-medical people, will not recommend internal catheters or the procedure called "clean intermittent catheterization". Catheterization is an invasive procedure of inserting a tube through the urethra to reach the bladder and drain urine. We feel that any kind of internal catheterization is a medical issue and is best decided by a health care professional or under the care and supervision of a health care professional in concert with the patient. We do observe that anytime a foreign object is introduced into your body, there is risk of damage and causing an infection most often referred to as UTI (urinary tract infection).

An internal collection device, such as a catheter (a hollow plastic tube), may be recommended for certain individuals to ensure that the bladder is emptied on a regular schedule and does not overfill. Intermittent catheterization -- the periodic insertion of a catheter into the urethra, past the sphincter muscle and into the bladder -- is performed at regular intervals each day (usually every 3 to 6 hours). These devices are usually used in managing cases of neurogenic and overflow incontinence.

Catheters used for intermittent catheterization range in size. Catheters usually are attached to a drainage tube and/or bag. Since intermittent catheterization completely empties the bladder, wetting accidents can be avoided.

Intermittent catheterization poses a risk of infection because the catheter must pass from the external environment to the internal environment of the body. Therefore, hand washing is required before touching the catheter or drainage bag. In addition, the catheter should be cleaned after each use.

Source: The Urology Channel: http://urologychannel.com

An internet forum one day yielded this series of exchanges:
My doctor recommended either internal or external...he feels either is better than as he put it "incontinence".....
Lyle USA - Thursday, April 26, 2001

In my case it would be indwelling: I have been told by my district nurse that sheath catheters are not really suitable for someone as active as me. Whenever I've been in hospital I've had an indwelling catheter which I didn't enjoy much.
James Warren Winchester, UK - Thursday, April 26, 2001

Warren and Mandrax, what type of catheter are you being pressured into a Foley internal Catheter or a Condom external Catheter and by who.
Lyle PA USA - Thursday, April 26, 2001

Warren... you're not the only one who is pressured by Doctors, family etc, to use a catheter. There's a tide of "anything is better than diapers" thought in today's medical profession.
Mandrax USA - Thursday, April 26, 2001

We will discuss only the external collection devices consisting of condom caths and urinals. We caution you, again, to consult your health care professional to determine whether this incontinence management method is appropriate for you and your individual situation.
For information regarding internal catheters, check out the information at the following site where they talk about the different types of internal catheters and how to take care of them.  Medical Supply.