Lec 3 Flashcards
What kind of complex meylin is ?
Protein lipid complex
What cells make myelin in cns , pns
Oligodendrocytes, schwann
What is the predominant component of white matter
Myelinated axons
What is the function of myelin
İnsulation of axons , quick transmission of neural signals
What is the main pattern of myelin injury in pns
Segmental demylination
Causes of demylinating neuropathies
Hereditary , immune destruction of myelin
Segmental demylination is related to which cell
Schwann , and can be primary or secondary due to axonal damge
Hypertrophic neuropathy is a complication of which disease , what is its appearance under the microscope
Due to re - demylination cycles of schwann cells in segmental demylination , onion bulb appearance
What is the clinical features of perephiral neuropathy related to segmental demylination
İmpaired function of the damaged nerve : muscle weakness and atrophy , pain , loss of sensation , parasthesia , AN dysfunction ( loss of bowel , bladder control )
What is parasthesia
Any abnormal sensation , numbness, pricking , tingling , burning sensation without real physical stimulus
What are peripheral neuropathies
Affects the function of one or more peripheral nerves , devided into: Axonal neuropathy (axonal degeneration) 90% Demyelinating neuropathy (segmental)
The most common cause of generalised peripheral neuropathy
Diabetes ( diabetic neuropathy )
All causes of peripheral neuropathy
Axonal damage :
Diabetes most common
Others : amylodosis , tumor , trauma , alcoholism , neurotoxic drugs , infections , autoimmune , vasculitis, CRF , nutritional diff
So any toxins , infections , infiltrative diseases , vascular diseases
Demylinating : immune destruction , heridetary ++ diabetes
The Risk of developing diabetic neuropathy depends on
Duration of diabetes , level of control of blood sugar
What is the most dangerous about diabetic neuropathy
(Most imp )The presence of cardiovascular autonomic neuropathy.
And loss of feeling in the lower limb is a high risk for amputation