[kellyhound]

An arteriovenous fistula is an abnormal connection or passageway between an artery and a vein. It may be congenital, surgically created for hemodialysis treatments, or acquired due to pathologic process, such as trauma or erosion of an arterial aneurysm.

http://en.wikipedia.org/wiki/Arteriovenous_fistula

[profezzorx]

That's insane... It looks like a snake crawling through his vein.

[rheedork]

Looks almost like a scene from alien.

[LadyCPlum]

Holy crap, does he have a baby Sandworm in there? Is it Wormsign?

[corpsehands]

That's a conversation starter.

[vagabond]

Wow! Never seen anything like that before- wonder if it's painful

[mintycbo]

Sounds about as pleasant as it appears...

Older guy in second pic.. he doesn't look to be in any distress from it pain-wise.

Breaking it down to just 3 words, artery. vein. fistula.
It would make me think it is a vein that connects to an artery.. like a bypass of sorts.
I'm sure this isn't good for the cardiovascular system...

[Faline]

Freaky looking

[candice81]

I want to grab it

[Darkest Angel]

Looks like the large intestine got rerouted. Just nasty, cover that up!