Aksonivaurioon

Aksonivaurioon, or axonal injury, is a term used in neuroscience to describe damage to the axon, the long projection of a neuron that transmits electrical signals. The injury can be focal or diffuse and may involve disruption of axonal transport, cytoskeletal damage, and, in severe cases, degeneration of the distal axon known as Wallerian degeneration.

Causes and contexts include traumatic brain injury, spinal cord injury, ischemic stroke, and various demyelinating or neurodegenerative diseases. Diffuse axonal injury is a common form in high‑impact trauma and results from shearing forces that injure many axons across different brain regions.

Pathophysiology typically involves mechanical disruption of the axonal membrane, abnormal calcium influx, cytoskeletal breakdown, and impaired transport of essential organelles and molecules. This can lead to swelling, disconnection from neuronal networks, and, over time, distal degeneration and impaired neural signaling. The severity and location of the injury often determine functional outcomes.

Diagnosis relies on clinical assessment supported by neuroimaging and biomarkers. Diffusion-weighted magnetic resonance imaging and diffusion tensor imaging are particularly useful for assessing axonal integrity, while biomarkers such as neurofilament light chain and tau can indicate ongoing axonal damage in cerebrospinal fluid or blood.

Treatment focuses on preventing secondary injury, stabilizing the patient, and maximizing recovery through rehabilitation. There is no definitive cure for axonal injury itself, but emerging therapies target neuroprotection, remyelination, and axonal regeneration. Prognosis varies with the extent of axonal damage, affected regions, and the timeliness of supportive care, with outcomes ranging from partial recovery to long-term disability.