Posterior Cortical Atrophy is a very rare form of dementia which affects the part of the brain at the back (posterior) of the head. The gradual and progressive degeneration of the cortex, which is the outer layer of the brain, compares to changes which occur in Alzheimer’s disease. It is not yet fully understood whether Posterior Cortical Atrophy (PCA) is a stand-alone condition or whether it is a variant of Alzheimer’s because the changes, or atrophy, that occur in the brain can also resemble Lewy Body dementia or Creutzfeldt-Jakob disease and other neurological conditions. Here is a brief overview of this condition.
Symptoms and causes of PCA
One of the first indications that a person may be experiencing the onset of PCA concerns gradually declining vision, indicated by difficulty reading, recognising faces or familiar objects and a gradual inability to judge distances. Disorientation, an inability to distinguish between stationary and moving objects and new difficulty in using tools or common household items are consistent with the slow degeneration of the posterior cortex.
In some cases, symptoms such as difficulty in performing previously easy tasks such as spelling or mathematical calculations can manifest. Some people start to have hallucinations and at a later stage in the development of the condition memory can start to fail. As a person gradually becomes aware of these changes they can become anxious and fearful.
Little is known about the causes of PCA, and it is not known if risk factors for Alzheimer’s disease are the same for PCA.
What is known is that there are as yet no standard diagnostic criteria so doctors must utilise a combination of tests including MRI brain scans, blood tests and neurological (cognitive) tests in order firstly to rule out any other possible conditions.
Because PCA is such a rare condition and the early symptoms are similar to other, relatively ‘normal’ conditions which arise from getting older, it is difficult at first to get a correct diagnosis. As the initial symptoms relate to deteriorating vision a person is likely to seek an appointment with an optician to check their eyesight so this can delay a correct diagnosis.
As symptoms can start to show between the ages of 50 and 65 diagnostic tests have in particular to rule out the possibility of a stroke or tumour.
Treatment and Prognosis
As yet there is no cure for Posterior Cortical Atrophy, but doctors can help to manage the condition using a combination of medications where appropriate, including those for anxiety and depression, and cognitive or physical therapy. Sufferers may benefit from care in their own home, which could enable them to stay in familiar, comforting surroundings instead of what could be a stressful and confusing move to a care home.
As PCA resembles Alzheimer’s in some cases, it is thought that medications which are used to slow down the progression of Alzheimer’s may help however this has not yet been proven to work, possibly because people with PCA show degeneration in a different part of the brain compared to those with typical Alzheimer’s disease. It must be pointed out that the benefits and risks of any treatments for PCA have not yet been established by the medical and scientific professions.
Discussions continue to find out whether PCA should be classified as a form of Alzheimer’s disease or as a separate condition in its own right.
Read more about different types of dementia in our guide Understanding Dementia