If the findings of a new study are anything to go by, high altitude flying, above 18,000 feet, leads to heightened chances of bruises in the brain.
The study suggests that pilots of U.S. Air Force U-2 reconnaissance planes, who routinely fly at high altitudes, suffer from decompression sickness and the incidence of the disease has tripled over the last two decades.
For the purpose of the study, researchers analyzed the brain scans of 102 male and female U-2 pilots and compared them with the brain scans of 91 people of similar demographic and health profile.
The analysis revealed that the U-2 pilots had 295 percent more lesions and close to 400 percent more brain lesions by volume vis-à-vis the non-pilots.
Decompression tends to send small bubbles, called emboli into the brain. The emboli may not make people ill but has the potency to cause harm, said study lead author Dr. Stephen McGuire, a neurologist with the U.S. Air Force School of Aerospace Medicine in San Antonio, Texas.
“If the bruise is not too severe, the brain recovers. We don’t really know what the long-term implications are,” averred McGuire.
In addition to pilots, miners, mountain climbers and scuba divers are affected by decompression sickness, also known as ‘bends’. The condition occurs when the atmospheric pressure around a person dips. The blood tends to boil at low pressures.
The Phenomenon Explained
“Tiny bubbles of nitrogen gas form in the blood and coalesce in the blood vessels of the joints. Bubbles can also coalesce in the blood vessels of the skin, causing itching and skin rash. Most dangerously, the blood vessels of the brain and spinal cord can be involved, causing multiple small strokes,” Dr. Adam Bender, a neurologist said explaining the phenomenon.
The effect of bends is thus “similar to the bubbles seen when you quickly open a bottle of soda or champagne.”
The symptoms of lesions range from slightly slowed thought process to relentless speech difficulty, perplexity and unresponsiveness.
The findings of the study have been published in journal Neurology.