Godfrey Hounsfield left school at 16 with a report detailing his “intellectual retardation”. He could not have known that he would go on to invent the CT scanner, revolutionise medicine and win a Nobel prize.
And he certainly could never have imagined that almost half a century later, his scanners would be put to work more than a kilometre under the sea.
The move to reengineer the technology for use under the waves was made by Tracerco, a UK-based business which helps oil and gas companies improve their operations.
“Shell came to us because they needed to find out what was causing a restriction in a pipe at a field in the Gulf of Mexico,” recalls Lee Robins, Head of Subsea Services of Tracerco.
“We were already looking at the possibility of using CT scanning technology to inspect pipes for corrosion, then we realised we could use it to see what was inside the pipes too. It was the perfect solution.”
The technology, which is not yet a routine part of inspections but could become one, is essentially the same as that used in hospitals.
The patient, or subsea pipeline, sits in the middle of a doughnut-shaped machine. On one side is a source of radiation and on the other are detectors. The detectors pick up variations in the radiation level, which depends on the density of the substances it travels through.
The doughnut shape allows both the source and the detectors to move in a circle around the patient or pipeline, with images taken from a multitude of angles. A computer can then take the data and translate it into an image.