CIDP

abnormal myelination of peripheral neurons. Also known as “onion bulb formation,” this pathologic myelination pattern can be seen with repeated cycles of demyelination and re-myelination around small thinly-myelinated nerve fibers. Onion bulb formation can be appreciated with chronic inflammatory demyelination disease and hereditary demyelinating neuropathies. Charcot Marie Tooth type 2 disease is an axonal hereditary neuropathy.