Every 40 seconds, someone in the United States has a stroke, and every four minutes, a stroke is fatal. One of the keys to surviving a stroke is getting medical attention as quickly as possible. Scientists have developed a portable helmet that will help those with strokes and head injuries.

This helmet is a miniaturized positron emission (PET) scanner like those that take up a small room at many hospitals. A PET scan measures important functions such as blood flow, oxygen use and sugar metabolism to help evaluate organ and tissue function. Small amounts of radioactive materials called radiotracers are inhaled, swallowed or injected depending on the organ. A special camera detects the signal from the radiotracers and a computer turns the signals into images of the organ(s) of interest. PET scans reveal both the structure of the organ and its cellular metabolism. The radiotracers leave the body in about two to 10 hours and the radiation exposure is not dangerous.

A stroke happens when the blood flow to a part of the brain is disrupted either by a blockage in a blood vessel, called an ischemic stroke, or by the rupture of a blood vessel, called a hemorrhagic stroke. The two types of stroke are treated differently, so determining the type of stroke is vital. Without the oxygen supplied by the blood vessels, the cells in the brain begin to die. Rather than wheeling a patient to the room-sized PET scanner in most hospitals, this portable PET scanner helmet can be brought to the bedside or be used in an ambulance, reducing the time it takes to get a diagnosis and limiting the resulting brain damage.

The key to a good outcome after a stroke is how rapidly treatment is initiated. For ischemic strokes, that means administering medication to break up the clot that stopped blood flow. For hemorrhagic strokes, treatment focuses on controlling the bleeding in the brain, alleviating pressure on the brain and possibly surgery to repair broken blood vessels. The effect of the stroke depends on the area of the brain affected and how much of it was damaged. Recovery from a stroke takes time and involves rehabilitation to regain strength and function as much as possible.

The device is about the size of a motorcycle helmet, and it produces detailed images of the brain that could be used to determine the type of stroke and regions of brain damage. A portable PET scanning helmet could be used on athletes to determine if they have a concussion, sent into the field for use on injured soldiers or become part of the standard equipment carried by ambulances and paramedics.

A potential issue is the weight of the PET scanning helmet. There are two versions, one which weighs 6.6 pounds and the other 20 pounds. However, scientists designed a counterweight system to take the weight off patients’ necks, and future designs will likely be much lighter. The developers anticipate that their device will become available in a couple of years.

Medical Discovery News is a weekly radio and print broadcast highlighting medical and scientific breakthroughs hosted by professor emeritus Norbert Herzog and professor David Niesel, biomedical scientists at the University of Texas Medical Branch at Galveston. Learn more at www.medicaldiscoverynews.com.