It is currently 10 Dec 2019 12:49

All times are UTC + 5:30 hours [ DST ]




Post new topic Reply to topic  [ 3 posts ] 
Author Message
PostPosted: 07 Nov 2014 00:20 
Offline
User avatar

Joined: 26 Feb 2013 10:59
Posts: 664
I saw a very interesting article in the Times Magazine recently. Mrs Blumenthal a youthful lady in her early 60s was used to running down the stairs, enjoyed driving her car, play the piano and was very good at painting and sketching horses. About 5 years ago her visual function, orientation and spatial awareness began to deteriorate. She would miss her chair and land on the floor in a train or at home. She would miss a step on a stair and end up sprawled at the bottom. No one could understand the reason as she looked normal and could speak and think rationally.

Driving which used to be a pleasure became a nightmare. She could not keep to a lane and would constantly hit the kerb or clip the wing mirror of an oncoming car. Reversing and parking became a nightmare. The stairs used to sway before her and coming down the stairs became frightening. She became petrified of using escalators. When she tried to play the piano the music score appeared jumbled that she could not read and hence was unable to continue. When she tried to read to her mother from her favourite book she could not comprehend the lines, the letters danced in front of her eyes and she could not proceed. Her mother who suffered from dementia and Parkinsons disease looked at her and told her that she hoped she was not getting the same disease that she herself was suffering from.

Mrs Blumenthal went to see her GP after this and discussed her fears. After examining her, he told her that she was imagining things and that she was perfectly normal. He added that perhaps she was suffering from depression / anxiety. She was not convinced as she was losing her confidence rapidly. A few months ago she saw her optician and told him about her problem. He checked her for macular degeneration and said he could find nothing wrong with her eyes. However he suggested that she should seek a neurologist's opinion. The neurologist saw her and after extensive psychological tests and a brain scan confirmed that she was suffering from Posterior Cortical Atrophy. The scan showed substantial atrophy of the posterior cortex of the brain. Although she was told that there was no definite cure she did feel relieved as a diagnosis had finally been made for her odd symptoms.

She is now under a neurologist and a neuropsychologist who are monitoring and helping her to cope with the symptoms at John Radcliffe Hospital in Oxford.

Take Home Point for Doctors: Listen to your patients carefully. Spend time with them. Do not brush aside their odd symptoms as imaginary. If you are unable to find anything wrong clinically send them for a second opinion.


Last edited by Badri on 03 Jan 2015 18:24, edited 2 times in total.

Top
 Profile Send private message  
 
PostPosted: 07 Nov 2014 01:07 
Offline
User avatar

Joined: 26 Feb 2013 10:59
Posts: 664
What do we know about PCA?

Posterior Cortical Atrophy (PCA) is a rare disorder where people lose the ability to interpret what they are looking at. It is also called Progressive Visuospatial Dysfunction. PCA is often missed as patients appear normal both physically and mentally. Some consider it as a variant of Alzhemier's disease and while others feel that it should be treated as a separate disease entity. 5% of patients with Alzhemiers were noted to have PCA. It affects younger individuals in their 50s and 60s whereas alzhemier's affects people older than 65.

Symptoms

Symptoms may vary from patient to patient. As it affects the posterior cortex of brain, the most common symptoms are due to difficulty with processing visual information such as reading a line of text, judging distances, distinguishing between stationary and moving objects, inability to perceive more than one object at a time, disorientation and difficulty identifying and using common objects. Difficulty recognizing what or who one is looking at. Difficulty with tasks like telling time or reading. They may complain that their vision is blurry, but this is not corrected by prescribing glasses.

It is a progressive disease. It would normally worsen over a period of time. The progression would depend on how fast the symptoms appeared in the first place.When symptoms progress, some people develop difficulty with attention and concentration and difficulty using objects correctly even if they know how. Depression is common as well. Unlike in Alzhemier's, patients with PCA appear normal and can indulge in a normal conversation. Their memory appears preserved.

Prevalence
There is no standard definition of PCA and no established diagnostic criteria at the moment. Some studies have found that about 5 percent of people diagnosed with Alzheimer’s disease have PCA. However, because PCA often goes unrecognized, the true percentage may be as high as 15 percent. Researchers and physicians are working to establish a standard definition and diagnostic criteria for PCA.

Causes and Risk Factors
Similar to Alzheimer’s disease, the causes of PCA are unknown, and no obvious genetic mutations have been shown to be linked to the condition. It is also not known if the risk factors for Alzheimer’s disease are also risk factors for PCA.

Pathology
The affected part of the brain shows amyloid plaques and neurofibrillary tangles, similar to the changes that occur in Alzheimer’s disease but in a different part of the brain.

Diagnosis
Misdiagnosis of PCA is common, owing to its relative rarity and unusual and variable presentation. At the moment diagnosis of PCA is based on the signs and symptoms. An MRI scan and a basic blood test should be done to rule out other major causes. Characteristic features that are sometimes used for diagnosis include gradual onset of visual symptoms with preservation of normal eye function and preservation of memory.

Many of the studies report that MRI in PCA showed a pattern of atrophy affecting occipital, parietal and posterior temporal lobes. The pattern is usually bilateral, but more severe on the right. Patients with PCA showed greater atrophy in the right visual association cortex than patients with typical AD, whereas those with AD showed greater atrophy in the left hippocampus than those with PCA.

Treatment
Medications:
There are no medications for PCA. It has been suggested that drugs used to temporarily alleviate brain dysfunction in Alzheimer’s disease may be helpful in PCA, but this is not proven. Depression related to PCA can also be treated with medications.

Non-pharmacological interventions:
People with PCA and their caregivers can often use strategies to help get around problems with visuospatial processing. For instance, items can be color coded for easier identification. Large text may actually be harder to read, so small labels and print may be more useful. Arranging things neatly and in the same place at all times is helpful.


You do not have the required permissions to view the files attached to this post.


Top
 Profile Send private message  
 
PostPosted: 09 Nov 2014 04:38 
Offline
User avatar

Joined: 24 Mar 2013 02:28
Posts: 707
Superb presentation Badri, Thank you for a heads up on this condition.

Allow me to present another real life case study. The more we read about case studies on different conditions it would register better when it comes into differential diagnoses.

PRIMARY VISUO-SPATIAL DYSFUNCTION.. The Cue is in this definition.

A 62 year-old right-handed woman with four years of progressive visuospatial dysfunction.

Her first symptom was difficulty seeing when driving at night. In the following years she frequently “dented” her car when parking, tended to “bump” into doors on her right side and had trouble locating items even when they were directly in front of her.

She reported problems reading, trouble distinguishing between currency bills and difficulty deciding whether to push or pull a door in order to open it. When she watched television, images appeared to “move slowly.”

She was referred to the cognitive neurology clinic by an ophthalmologist who had ruled-out primary ocular disease.

On neurologic evaluation she was fully oriented and was an excellent historian. On visual fields testing she was inconsistent counting fingers in the right hemifield.
Pupillary responses and extraocular movements were normal, though she was slow initiating saccades and had difficulty reaching for items under visual guidance.

Her physical neurologic examination was otherwise normal. On cognitive testing MMSE was 26/30, and she showed severe impairment when copying intersecting pentagons and the Benson figure .

She was able to name colours correctly but showed moderate difficulty matching faces. She had severe difficulty reading, which was improved by spelling words out loud, and had mild deficits in confrontation naming (improved with cues) and category fluency.

Verbal memory, phonemic fluency and attention were intact.

She could not complete many tasks due to visual dysfunction.

Brain MRI showed marked atrophy in bilateral parietal, posterior temporal and lateral occipital cortex and FDG-PET showed hypometabolism in the same regions, left worse than right.
Frontal cortex, medial temporal cortex and hippocampus were spared.
PIB-PET showed diffuse cortical uptake throughout posterior and anterior cortical regions consistent with underlying amyloid-beta plaques.

Medications.

Although there are no published reports that assess the effectiveness of acetyl cholinesterase inhibitors (e.g. donepezil, rivastigmine and galantamine) in PCA, these are used frequently, given that Alzheimers is statistically the most likely underlying pathology . Clinical experience and limited single case reports suggest some clinical benefit, most likely in patients with underlying AD or DLB ( dementia with Lewy body) pathology.
It may also be appropriate to consider anti-depressant medication in patients with persistent low mood, and levodopa/carbidopa in patients with parkinsonism.

G MOHAN.


Top
 Profile Send private message  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC + 5:30 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron