How does cryogenics work? The science behind body preservation

The technology behind cryogenic preservation has been around since the 1960s but it is carried out in only three clinics – two in the United States and one in Russia – and only a few hundred bodies have been frozen in this way.

The idea is that if a body is cooled quickly enough, it will avoid the oxygen deprivation which causes most damage to the brain and that a body thus preserved could be revived years or decades in the future and cured of whatever illness was the cause of death.

As soon as possible after death, the body is put in an ice bath, the blood is removed and the body is pumped full of a solution designed to preserve the organs. It remains packed in ice as it is shipped to the cryonics facility, where the body is cooled by nitrogen gas, bringing the temperature down to minus 110C.

The temperature is lowered even further, to minus 196C, over the next two weeks before the body is suspended in a tank of liquid nitrogen until the day it will be revived.

Scientists have not yet shown that they can revive a frozen body without damaging cells and nobody knows if someone revived in such a way would retain his or her memory. Researchers celebrated a breakthrough in February this year, however, when they returned a cryogenically frozen rabbit brain “near perfectly” from preservation.

The body of the girl at the centre of the British court case was taken to the Cryonics Institute near Detroit, Michigan, where 142 other bodies are currently preserved. The facility advertises cryopreservation packages from $28,000 to $35,000, which does not include the cost of transporting the body there.

TV chat show host Larry King and musician Britney Spears are among those who have expressed an interest in being cryogenically frozen. For many years, it was rumoured that Walt Disney ordered that his body should be frozen after his death in 1966, and that he should be "woken up" in 50 years, by which time he expected a cure for lung cancer to be found.

If this were true, he would be due to be defrosted next month. His family confirmed a few years ago, however, that Disney was not frozen, but cremated.