Search results
Results from the WOW.Com Content Network
Acute motor axonal neuropathy (AMAN) is a variant of Guillain–Barré syndrome. It is characterized by acute paralysis and loss of reflexes without sensory loss. Pathologically , there is motor axonal degeneration with antibody-mediated attacks of motor nerves and nodes of Ranvier .
In regards to the pathophysiology of ulnar neuropathy:the axon, and myelin can be affected. Within the axon, fascicles to individual muscles could be involved, with subsequent motor unit loss and amplitude decrease. Conduction block means impaired transmission via a part of the nerve.
Such lesions give rise to extensive astrocyte loss, which may occur in part in the absence of any other tissue injury, such as demyelination or axonal degeneration (lesion type 5). Finally, lesions with a variable degree of astrocyte clasmatodendrosis are found, which show plaque-like primary demyelination that is associated with ...
By the time chronic nerve compression becomes symptomatic, myelin tissue in the area of compression is likely damaged triggering a process called demyelination. This only affects the myelin sheath on myelinated axon while the axon and nerve continuity will remain preserved. [2]
Two primary classifications exist: demyelinating (Schwann cell damage) and axonal (direct nerve fiber damage). [7] [16] Each of these then branches into additional sub-classifications depending on the exact manifestation. In all cases, however, the condition results in weakness or paralysis of limbs, the potentially fatal paralysis of ...
Wallerian degeneration occurs after axonal injury in both the peripheral nervous system (PNS) and central nervous system (CNS). It occurs in the section of the axon distal to the site of injury and usually begins within 24–36 hours of a lesion. Prior to degeneration, the distal section of the axon tends to remain electrically excitable.
Alcoholic polyneuropathy usually has a gradual onset over months or even years, although axonal degeneration often begins before an individual experiences any symptoms. [ 2 ] The disease typically involves sensory issues and motor loss, as well as painful physical perceptions, though all sensory modalities may be involved. [ 3 ]
The hallmark feature of diabetic polyneuropathy is a blend of axonal and demyelinating damage, which results from mechanical demyelination and channel/pump dysfunctions. [6] Diabetic patients have been found to experience a significantly shorter strength-duration time constant and a much higher rheobase than normal patients. [6]