Skip to main content

Neuropathology of Alzheimer's Disease

Image
By

    Neuropathology of Alzheimer's Disease

    Gross Brain Changes

    The following are the gross changes in the brains of the people with Alzheimer’s disease:
    1. Reduced weight of the brain
    2. Reduced cortical volume
    3. Dilated ventricles
    4. Deepening of sulci

    Magnetic Resonance Imaging

    On magnetic resonance imaging, the diagnostically most important finding is atrophy, especially of the medial temporal lobe. It affects the entorhinal cortex the earliest but then it spreads to other regions of the temporal lobe and limbic lobe for example hippocampus, amygdala, and parahippocampus. Later, the pathology extends to parietal lobe and eventually global atrophy. It spares frontal lobes until the late stage. The progression of atrophy occurs in a similar pattern as the progression of the neuropathology.

    Dilated ventricles can show global atrophy, but the most reliable method is a direct measurement of volume. Expansion of the fissures is the indirect, and less reliable way to measure the atrophy. For Alzheimer’s disease, fissures/sulci in the temporal lobe and parietal lobe are more important.

     Parietal atrophy relates to the early onset subtype of Alzheimer’s Dementia.

    It begins in the Entorhinal Cortex. 

    References

    Johnson, K. A., Fox, N. C., Sperling, R. A., & Klunk, W. E. (2012). Brain imaging in Alzheimer disease. Cold Spring Harbor perspectives in medicine, 2(4), a006213. doi:10.1101/cshperspect.a006213

    Alzheimer disease | Radiology Reference Article | Radiopaedia.org. (n.d.). Retrieved January 17, 2020, from https://radiopaedia.org/articles/alzheimer-disease-1

    Comments

    Post a Comment

    Your Thoughts?

    Popular posts from this blog

    ICD-11 Criteria for Depression (Recurrent Depressive Disorder) 6A71

    By
    ICD-11 Criteria for Depression (Recurrent Depressive Disorder) 6A71 Recurrent depressive disorder is characterised by a history or at least two depressive episodes separated by at least several months without significant mood disturbance. A depressive episode is characterised by a period of depressed mood or diminished interest in activities occurring most of the day, nearly every day during a period lasting at least two weeks accompanied by other symptoms such as difficulty concentrating, feelings of worthlessness or excessive or inappropriate guilt, hopelessness, recurrent thoughts of death or suicide, changes in appetite or sleep, psychomotor agitation or retardation, and reduced energy or fatigue. There have never been any prior manic, hypomanic, or mixed episodes, which would indicate the presence of a Bipolar disorder. Inclusions:                Seasonal depressive disorder Exclusions:    ...
    Post a Comment
    Read more

    ICD-11 Criteria for Schizophrenia (6A20 )

    By
    ICD-11 Criteria for Schizophrenia (6A20 ) Schizophrenia is characterised by disturbances in multiple mental modalities, including thinking (e.g., delusions, disorganisation in the form of thought), perception (e.g., hallucinations), self-experience (e.g., the experience that one's feelings, impulses, thoughts, or behaviour are under the control of an external force), cognition (e.g., impaired attention, verbal memory, and social cognition), volition (e.g., loss of motivation), affect (e.g., blunted emotional expression), and behaviour (e.g., behaviour that appears bizarre or purposeless, unpredictable or inappropriate emotional responses that interfere with the organisation of behaviour). Psychomotor disturbances, including catatonia, may be present. Persistent delusions, persistent hallucinations, thought disorder, and experiences of influence, passivity, or control are considered core symptoms. Symptoms must have persisted for at least one month in order for a diagnosis of schi...
    Post a Comment
    Read more

    ICD-11 Criteria for Bipolar Type-1 Disorder

    By
    ICD-11 Criteria for Bipolar Type-1 Disorder    6A60     Bipolar type I disorder is an episodic mood disorder defined by the occurrence of one or more manic or mixed episodes. A manic episode is an extreme mood state lasting at least one week unless shortened by a treatment intervention characterised by euphoria, irritability, or expansiveness, and by increased activity or a subjective experience of increased energy, accompanied by other characteristic symptoms such as rapid or pressured speech, flight of ideas, increased self-esteem or grandiosity, decreased need for sleep, distractibility, impulsive or reckless behaviour, and rapid changes among different mood states (i.e., mood lability). A mixed episode is characterised by the presence of several prominent manic and several prominent depressive symptoms consistent with those observed in manic episodes and depressive episodes, which either occur simultaneously or alternate very rapidly (from day to day or with...
    Post a Comment
    Read more