Program Operations Manual System (POMS)
TN 53 (08-22)
DI 23022.643 Posterior Cortical Atrophy
COMPASSIONATE ALLOWANCES INFORMATION
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POSTERIOR CORTICAL ATROPHY
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ALTERNATE NAMES
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PCA; Benson’s Syndrome; Biparietal Alzheimer Disease; Primary Visual Agnosia; Visual
Variant of Alzheimer’s Disease; VVAD
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DESCRIPTION
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Posterior Cortical Atrophy (PCA) is a rare neurologic disease characterized by impairment of higher visual processing
skills and other posterior cortical functions without any evidence of ocular abnormalities,
relatively intact memory and language in the early stages. PCA causes atrophy of the
posterior part of the cerebral cortex, resulting in the progressive disruption of
complex visual processing. This rare form of dementia is considered a visual variant
or an atypical variant of Alzheimer’s disease (AD).
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DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM/ICD-10-CM
CODING
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Diagnostic testing: The cause of PCA is unknown, and there are no fully accepted diagnostic criteria
for the disease. This is partially due to the gradual onset of PCA symptoms, their
variety, the rare nature of the disease, and the younger age of onset.
The following may assist with diagnosis:
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A history and physical exam;
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Neuroimaging (MRI, CAT scan) showing atrophy affecting occipital, parietal, and posterior
temporal lobes bilaterally, many with more severe change on the right; and
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Careful observation in relation to PCA symptoms.
Physical findings: Individuals with PCA may present with:
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Issues with depth perception;
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Trouble navigating through space;
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Apraxia (disorder of movement planning);
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Alexia (impaired ability to read);
ICD-9: 377.7
ICD-10: R48.3
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PROGESSION
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PCA usually affects people at an earlier age than typical cases of Alzheimer's disease,
with initial symptoms often experienced in people in their mid-50s or early 60s.
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TREATMENT
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Specific and accepted treatment for PCA has yet to be discovered; this may be due
to the rarity and variations of the disease. At times people with PCA are treated
with AD treatments such as, cholinesterase inhibitors, donepezil, rivastigmine, galantamine,
and memantine. Antidepressant drugs have also provided some positive effects.
Other treatments such as occupational therapy or help with adapting to visual changes
may help.
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SUGGESTED PROGRAMMATIC ASSESSMENT*
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Suggested MER for Evaluation:
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Clinical history and examination that describes the diagnostic features of the impairment;
and
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Suggested Listings for Evaluation:
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DETERMINATION
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LISTING
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REMARKS
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Meets
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11.17 B
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Equals
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* Adjudicators may, at their discretion, use the Medical Evidence of Record or the
listings suggested evaluating the claim. However, the decision to allow or deny the
claim rests with the adjudicator.
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