In stomach-churning scenes the doctor quickly cleans up the wound

Dr Lee presses down hard with a new tool and pus

This is the revolting moment Dr Pimple Popper bursts the 'mother of all cysts' on a man's head and reams of fluid spurt out.

An elderly gentleman had developed a massive growth on his head, so where else could he turn but to famous dermatologist Dr Sandra Lee?

At the start of the nauseating video she cuts into the massive cyst with a knife.

She says: 'Wow you really left this thing alone, didn't touch it at all.'

Then using a new device she presses down hard around the cyst.

Pus starts to ooze out of the hole before being promptly pulled away by the good doctor.

She then starts to clean up the resulting wound before sewing up the gap.

The repellent video, posted on May 8, has already been viewed well over one million times.

Dr Lee, who works at Skin Physicians & Surgeons in Upland, California, titled the YouTube video: 'The Biggest Dilated Pore of Winer?!'

But underneath the clip she wrote: 'Today I present to you a "mother" of a cyst. I mistakenly call this a dilated pore of Winer when in actuality I would say this is an epidermoid cyst…

'…we sent it for pathology and it was confirmed to me a benign epidermoid cyst microscopically.

'There ya have it! Now go enjoy this great day with the ones you love, and give your momma a big hug and pop 'em a kiss from me too, if you can!'

Epidermoid cysts are non-cancerous lumps beneath the skin, which commonly appear on the face, neck and torso.

They occur when hair follicles become blocked with wet, dead, skin cells.

Massive cyst: The stomach-churning moment Dr Pimple Popper squeezes a massive cyst on man's head

Revolting: She uses a new tool to press down on the growth which explodes in a mountain of pus

A bag - called a sac - forms around the mashed up cells, and it can continue to grow bigger as the skin regenerates itself - causing a raised lump.

They are slow growing and painless, and rarely cause problems or need treatment.

Today I present to you a 'mother' of a cyst Dr Pimple Popper

However, sometimes they need to be removed if they become painful, ruptured or infected.

Commenters expressed mixed reactions of pain, shock and pleasure at viewing the footage.

One wrote: 'I'm eating lunch as I watched this. It's still so satisfying to watch.'

While another posted: 'Ok, I am a tough cookie but gheez that's just nasty.'

And user Manny Pena wrote: 'You know when the camera zooms in, something is about to gooo downnn!'

In another video discussing her success, Dr Lee said: 'I feel like I have really brought this sort of thing out of the closet, in a way.

'Previously people were hiding in their rooms, at their computer sweating and worried that someone was going to come in and catch them looking at pimple porn.