When someone suffers a stroke, 1.9 million nerve cells in the brain die each minute, and the oxygen-starved brain ages about 3.6 years each hour -- further emphasizing the need for rapid treatment -- researchers say.”'Time is brain’ is a popular saying: clinical outcomes have been shown to deteriorate the longer treatment is delayed,” study author Dr. Jeffrey L. Saver, from the University of California in Los Angeles, told Reuters Health. However, he added, until recently the technology did not exist to precisely count the number of neurons lost with each passing minute that the blood supply is interrupted to the affected region.Advances in stroke neuroimaging coupled with data from previous research have allowed Saver to estimate the neuron loss that occurs during a typical stroke.The average stroke involves 54 milliliters of brain tissue -- about 3 cubic inches -- and takes 10 hours to evolve, the investigator reports in the American Heart Association’s journal Stroke.As noted, each minute a stroke ticks by untreated, 1.9 million neurons die, resulting in the loss of 14 billion synapses (nerve junctions) and 7.5 miles of nerve fibers. According to the report, the forebrain, the most common site of strokes, contains a total of 22 billion neurons, on average.
