There was some discussion on this newsgroup about a study
(paid for by Pfizer of course) that showed men who took a
daily dose of Viagra after surgery were more successful at
preserving sexual function.

Somebody has studied the use of a vacuum erection device
(aka penis pump) for similar purposes and found that men who
use it starting one month after surgery preserved penile length
and function better, on average, than men who did not.

See: http://tinyurl.com/35k3yh

If the reason for this success is a "use or lose" syndrome,
i.e., if men who have no erections lose some of the capacity
for them, then I speculate that the pumps might also be
useful to men on hormone therapy, or men who have had
radiation that has reduced their potency.

Alan