Relation between multiple sclerosis (MS) and brain atrophy
MS Autoimmune demyelinating disease of nerve cell in brain , spinal cord characterized by various neurological disorders. More effect female then male , characterized by focal areas of white matter demyelination and gray inflammation (1). Brain atrophy, or brain shrinkage, is an important manifestation of multiple sclerosis It's one of the most destructive result of the disease (1) . Brain atrophy can be seen in the earliest stages of MS and may lead to irreversible impairments. Whereas, MRI lesions are highly distributed in white matter (WM) and gray matter, the brain tissue that appears in MRI is also affected by pathological studies (1). Causes of MS (unknown) and pathogenesis are cell mediated (type TV) hyper sensitivity reaction (2). T cell , B cell , Macrophages . T cell : break through blood brain barrier lead to activation by myelin proteins( myelin basic protein) , Th17 cell produced cytokines lead to the attract other leukocytes , Th1 cell produce interferon gamma lead to activation of macrophage ,so T cell produce cytokines (IL1 ,IL6 ,TNF-alpha) that lead to oligodendrocytes damaged , blood brain barrier express more receptors for other leukocytes , blood vessels dilate easier passage for other leukocytes (2). B cell: produce antibodies that bind to myelin protein and mark them(2) . Macrophage : recognize marked oligodendrocytes , engulf them attacks occurs in 2 stage ,early stage : regulator T cell reduce inflammation lead to oligodendrocytes heal , renew myelin (remyelination). Later stage : repetitive extensive damage lead to death of oligodendrocytes , loss of myelin ,damage ,loss axons . 4 types of MS: 1- Relapsing remitting multiple sclerosis (RRMS) bouts of autoimmune attacks ,months to year ,improvement after attack .2- primary progressive multiple sclerosis (PPMS)one constant attack lead to progression of disabilities over lifetime. 3- secondary progressive multiple sclerosis (SPMS) start as ( RRMS) ,over time become constant lead to progression of disabilities .4- progressive relapsing multiple sclerosis (PRMS) one constant attack , lead to faster progression of disabilities. Risk factor of MS 1- genetic factor : individuals who are biologically female twice as susceptible , polymorphisms of certain alleles of major histocompatibility complex (e.g HLA DR2 : identifying, binding of foreign molecules) .2- Environmental : infection (e.g Epstein Barr Virus infection ) , vitamin D deficiency , usually affects young adults.
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Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system characterized by focal or diffuse inflammation, demyelination, axonal loss and neurodegeneration. Brain atrophy can be seen in the earliest stages of MS . Atrophy of gray matter is associated with the degree of disability in patient with MS . In these study resulted show the use of the EDSS (expanded disability status scale ), together with MRI volumetric measures, ensures a reliable correlation between radiological appearance and clinical state and provides the best characteristic of functional impairments in MS . The aim of study was to evaluate the relationship between brain atrophy quantification in multiple sclerosis (MS) patients and the progression of disability measured by neurological tests.
