As a consequence, this is often responsible for the astrocytic plaques prominently noted in histological CBD examinations. Although they are understood to play a significant role in neurodegenerative diseases such as CBD, their precise effect remains a mystery.In recent years Corticobasal Degeneration is seen to be a tauopathy[22]. This is believed due to the most common indicator of CBD being a faulty tau protein. Tau proteins are integral in keeping microtubules stable and these defective cells create 4 microtubule-binding repeats[23]. These 4 binding repeats have increased affinity in binding with microtubules[25]. Because of this increased affinity, they form insoluble fibers (also called "paired helical filaments). Microtubules themselves keep the cell and cytoskeletal structure stable[24]. Thus, when Tau proteins create unnatural configurations, microtubules become unstable, and eventually leads to cell death. Diagnosis
New diagnostic criteria known as the Armstrong criteria were proposed in 2013, although the accuracy of these is limited and further research is needed. Criteria
Insidious onset and gradual progression
Lasts 1 year or more
Meets one of the four subtypes:
Possible CBS
FBS or NAV
PSPS plus at least one CBS feature other than limb rigidity or akinesia
No exclusion criteria present
More likely if onset is after age 50
More likely if no family history (2 or more relatives)
More likely if no genetic mutation affecting T (e.g., MAPT)

Possible corticobasal syndrome subtype
Symptoms may be symmetric or asymmetric.
Frequently, a differential diagnosis for CBD is performed, in which other diseases are eliminated based on specific symptoms that do not overlap. However, some of the symptoms of CBD used in this process are rare to the disease, and thus the differential diagnosis cannot always be used.Postmortem diagnosis provides the only true indication of the presence of CBD. Most of these diagnoses utilize the Gallyas-Braak staining method, which is effective in identifying the presence of astroglial inclusions and coincidental tauopathy. Overlap with other diseases
Progressive supranuclear palsy (PSP) is frequently the disease most often confused with CBD. Both PSP and CBD result in similar symptoms, and both display tauopathies upon histological inspection. However, it has been noted that tauopathy in PSP results in tuft-shaped astrocytes in contrast with the ring-shaped astrocytic plaques found as a result of CBD.Individuals diagnosed with PD often exhibit similar movement dysfunction as those diagnosed with CBD, which adds complexity to its diagnosis. Some other neurodegenerative diseases including Alzheimers disease (AD), dementia with Lewy bodies (DLB), chronic traumatic encephalopathy (CTE) and frontotemporal dementia (FTD) also show commonalities with CBD. Neuroimaging
The types of imaging techniques that are most prominently utilized when studying and/or diagnosing CBD are:
magnetic resonance imaging (MRI)
single-photon emission computed tomography (SPECT)
fluorodopa positron emission tomography (FDOPA PET)Developments or improvements in imaging techniques provide the future possibility for definitive clinical diagnosis prior to death.