This is consistent with previous ex vivo nerve studies in mouse models of HNPP, where similar MT effects were observed in the sciatic nerve of mice with PMP22 deletions and age‐matched wild‐type mice.38 The MTR findings herein are consistent with these ex vivo studies and are supportive of a length‐dependent axonal loss superimposed on the aforementioned focal abnormalities in HNPP. The gene discussed is PMP22; the disease is hereditary neuropathy with liability to pressure palsies.