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.
The layers are generally uniform and continuous, but due to imperfections in the process by which Schwann cells wrap around nerve axons, small pockets of residual cytoplasm may be left behind during myelin sheath formation. These pockets, called "incisures," can divide the myelinated axon into irregular segments.