A SCOTTISH girl has become the youngest child in the world to have "deep brain" surgery to calm uncontrolled muscle spasms.

Viktoria Kaftanikaite, aged just 32 months and from Glasgow, had electrodes inserted into her brain during deep brain stimulation (DBS) surgery at the Evelina Hospital in London, a specialist NHS children's hospital in London.

The procedure is designed to treat a condition called dystonia, which caused her arms and legs to flail about and her mouth to twitch constantly.

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The rare genetic disorder also left her screaming in unbearable pain, stopped her from eating and also affected her ability to breathe, putting her life at risk.

The youngster was airlifted to the Evelina children’s hospital from an intensive care unit in Glasgow in May.

She underwent the four-hour operation soon after.

Dr Jean-Pierre Lin, a consultant paediatric neurologist for the complex motor disorders service at the Evelina hospital, said: “In operating on Viktoria our neurosurgeons have broken the sound barrier in neurosurgery, by offering DBS at such a young age.”

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Viktoria is now recovering in an intensive care unit in Glasgow.

Her mother Patrycja Majewska said: “Viktoria had out of control movements all the time.

"Her arms and legs wouldn’t move normally and she was pushing her head down and her belly up.

“We noticed that from a young age she couldn’t hold anything in her hands, such as toys, and had trouble keeping her head up because it was falling from side to side. She wasn’t able to do anything, until now.”