These layers are generally uniform and continuous, but due to imperfect nature of the process by which Schwann cells wrap the nerve axon, this wrapping process can sometimes leave behind small pockets of residual cytoplasm displaced to the periphery during the formation of the myelin sheath. These pockets, or "incisures", can subdivide the myelinated axon into irregular portions.
These layers are typically uniform and continuous, but due to the imperfect nature of the Schwann cell wrapping process around the nerve axon, this wrapping can sometimes leave behind small pockets of residual cytoplasm displaced to the periphery during myelin sheath formation. These pockets, or "incisures," can divide the myelinated axon into irregular segments.