The sheathing has not been used in the UK since the 1980s and codes in the United States specifically prohibit their use in buildings of more than three or four storeys, he said.
The retinal nerve fiber layer is the one part of the brain where nerve cells are not covered with the fat and protein sheathing called myelin, making this assessment specific for nerve damage as opposed to brain MRI changes, which reflect an array of different types of tissue processes in the brain.