Well, not being familiar with "prolapsed internal ones", although I suppose they would be more originating from the inside rather than the outside, so I guess mine would have been classed as 'external' as they were evident on the outside on the anal sphincter muscle, does this define "external"? if so, then scroll down to a couple of my replies on this subject, if not, then pretend you never read this, but I got straight onto mine way before they got to the stage you're talking about.
I don't know how to put in a link or whatever it's called here so you'll have to scroll down for a bit, or alternatively, keep your fingers crossed and just ignore this.