Airline passengers at risk of developing DVT could be spotted through a high-tech intelligent seat design.
A prototype design of how the 'smart seat' would work
The 'smart-seat' works via a raft of built-in movement sensors. These are linked to a computer which tells cabin crew if a passenger has been still for too long, increasing their risk of DVT.
The seat could also indicate signs of too much movement, a potential sign of a nervous flyer.
DVT, or deep vein thrombosis, is the formation of a blood clot in one of the deep veins of the body, usually in the leg.
Sitting still for a long time, as happens on flights, is a significant risk factor for DVT.
If immobility was the only factor, this would be a very clever way of looking at it
Mr John Scurr, DVT expert
However, people are more likely to suffer from them if they are elderly or very overweight, or women who are on the Pill.
A prototype of the smart seat has been designed by UK company Qinetiq, as part of a project to redesign the interiors of planes to make them more comfortable to travel and work in.
The seat has a number of electrical sensors close to the head, the shoulders, lower back and legs.
These send data to a computer display which cabin crew could monitor.
If someone was still for too long, they could suggest they did some exercises in their seat, or walked around the cabin.
Dr Chris Thorpe, who designed the chair, told BBC News Online: "What you would be looking for is a low level of movement in the passenger for a long period of time."
He said exactly how long was difficult to determine.
Dr Thorpe added: "We want to make flying safer and more enjoyable for passengers, and to help cabin crew find out what's happening to passengers more accessibly."
He said the company was in discussion with several airlines about introducing the seats.
Dr Thorpe said the cost would not be prohibitive, and that airlines could introduce them during their regular revamps of upholstery.
But Mr John Scurr, a consultant vascular surgeon and DVT expert, said: "One thing we know that causes DVT is immobility, sitting still for a long period of time.
"But the most important risks are other factors. Getting on a plane is the final factor."
Mr Scurr said: "If immobility was the only factor, this would be a very clever way of looking at it."
But he added: "What we really need is the definitive answer as to what causes DVT."