Serious Constipation

Last year our cat was suffering with serious constipation
(googlegroups link he http://tinyurl.com/2z7k8n)

However in the last 6 months or so, he seems to be having to go back
to the vet for a clean out more and more frequently. The last time he
was at the vets for nearly a week, and he's been back now for less
than a week and seems to be suffering again (he's back to the vets
tonight).

We're trying to manage his condition with lactulose, and another
product which is supposed to force his innerds to contract and move
the stool along quicker (the name escapes me), but it doesn't seem to
be working at all.

This is all starting to sound worryingly like megacolon. I've heard
one of the solutions to this is to remove all or part of the colon.
Has anyone had any experience of a cat that has had this done ?




Here he is anyway:

http://www.facebook.com/photo.php?pi...d&id=627125965