Neck cushion threat to air passengers

They say the devices are potentially lethal and should be banned at once.

Ultrasound testing of the cushions has suggested that, in some circumstances, they could interrupt the blood supply to the brain.

Neck cushions are a frequent sight in the cabins of long-haul aircraft, wrapping around the back of the neck and supporting the head while the user sleeps.

The danger comes if the aircraft suffers a sudden loss of cabin pressure, say testers.

This could be caused by a computer fault, or perhaps a window blowing out.

Gets bigger

Because the pressure inside the cushion remains constant, it will expand - perhaps to three times its normal size.

This, they argue, could cut of the flow of blood to the brain, perhaps causing brain damage or even death.

In addition, the cushion could explode loudly, causing temporary deafness and perhaps damaging the vertebrae at the top of the spine.

Paul Richards, a former pilot himself - and the inventor of a device which allows a seated passenger to perform exercises which may ward off thrombosis - has also come up with a safety feature which releases the air inside the cushion in the event of decompression.

He believes that the cushions may have been the source of injuries to passengers in the past - but overlooked by doctors and researchers as a potential cause.

He told BBC News Online: "With any decompression in the cabin, the neck cushion grows and puts pressure on the neck.

"It can explode with a very high noise level - and possibly cause damage to the neck and injury to the spine."

He said: "I am calling on airlines to ban all unsafe inflatables from aircraft."

Aviation expert Dr Ian Perry said: "Having seen one or two tests, I think that these cushions are dangerous unless proved otherwise."

Ultrasound

Small-scale ultrasound tests carried out vascular surgeon Dr Mark Whiteley confirmed that the rapidly expanding cushion did have some effect on the flow of blood through the carotid arteries, which supply the brain.

"The worry with this sort of cushion is that if it did turn out to cause significant flow disturbance that can actually cause problems for the brain."