Surgeons extracting 26-year-old's 'brain tumour' discover embryonic growth with bone, hair and teeth

Plagued by a feeling something wasn't right, student Yamini Karanam sought medical help.

She was struggling to understand things she had read, and felt lost in conversations.

But the Indiana University PhD student could never have comprehended the source of the problem - an 'evil twin sister growing' in her brain.

Surgeons operating to extract what they believed to be a tumour in her brain, were shocked to discover the growth was in fact an embryonic twin, complete with bone, hair and teeth.

Known by its medical name, a brain teratoma, the growth is very rare.

Indeed, Dr Hrayr Shahinian, the expert at the Skullbase Institute in Los Angeles who operated on Miss Karanam, has removed around 7,000 brain tumours and has seen just two teratomas.

In the past, teratomas have been reported to contain hair, teeth, bone and rarely more complex organs including eyes, hands, feet and limbs.

And in some cases they have been found to resemble a foetus.

Miss Karanam first noticed something wasn't right last September, when she struggled to register things in her mind, NBC reported.

'If a couple of people were talking in a room, I wouldn't understand what was happening,' she said.

Frustrated at doctors' apparent inability to find an answer, the 26-year-old launched her own search for answers online.

It led her to the Skullbase Institute and Dr Shahinian, who has developed a minimally-invasive way of reaching deep into a person's brain to extract tumours.

The procedure, he said, is a type of keyhole surgery rather than traditional brain surgery, which involves opening the skull and using metal retractors to allow him to insert a microscope deep into the brain.

Instead, Dr Shahinian makes a half-inch incision in the brain to use fibre-optic technology and digital imagery to gently chisel away at the tumour.

Shocked when she woke to learn of Dr Shahinian's discovery, Miss Karanam branded the tumour her 'evil twin sister who's been torturing me for the past 26 years'.

Dr Shahinian said he feared the tumour could be cancerous.

But tests revealed the mass was benign, and Miss Karanam is expected to make a full recovery in just three weeks.

She said she wanted to raise awareness of Dr Shahinian's technique.

'This has to be mainstream,' she added. 'When they know you have a pineal tumour, they should tell you "you know what? There's a minimally invasive approach in which they won't kill you, they won't leave you with a disability.'

Prior to Dr Shahinian's keyhole approach, he said the only option was to remove half of the patient's skull to reach the tumour.

He added: 'We want to be in and out without the brain knowing we were there, and I think that's the beauty of this technique.'

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