Psychiatry - Frontotemporal Dementia Flashcards
Frontotemporal Dementia
Pick’s Disease
Causes?
- Genetic Association with chromosome 17q21-22
- Tau gene 3 mutations
Frontotemporal Dementia
Pick’s Disease
Signs & Symptoms?
Pick’s disease is a slowly progressive dementia that is characterised initially by:
- personality change, including:
- loss of motivation
- problems with concentration
- changes in moral attitudes
- loss of social skills
- Loss of self care
- Echolia (meaningless repetition of othr person’s speech)
Later the patient develops deficits in:
- intellect
- memory
- language
The usual age of onset is between 40 and 60. There is often atrophy of the frontal and temporal lobes of the brain.
Frontotemporal Dementia
Pick’s Disease
Investigations?
- MMSE
- MSE
- Addebrooke’s cognitive examination (ACE-III)
- CT,MRI, SPECT
Histology depends on:
Microvacuolar type -microvacuolation
Pick type - widespread gliosis, no micrvacuolation
MND type - histological changes like MND
Frontotemporal Dementia
Pick’s Disease
Frontal Lobe Signs?
Frontal lobe signs are focal neurological signs that may help to indicate a frontal lobe lesion. Related to precentral gyrus:
- monoparesis or hemiparesis depending on extent of damage
- focal motor seizures - either spreading with a Jacksonian march or rapid generalisation to give tonic-clonic seizures; status epilepticus is not an uncommon presentation of frontal lobe tumours
Related to Broca’s area:
- expressive/Broca’s dysphasia if in dominant hemisphere
Related to supplementary motor area:
- paralysis of head and eye movements to opposite side - head and eyes deviated towards side of lesion
Related to prefrontal area:
- change in personality - inappropriate jocularity, loss of initiative and concern, akinetic mutism, disinhibition, general retardation
- primitive reflexes - grasp, pout, palmar-mental, brisk jaw-jerk; changes in deep tendon reflexes contralaterally
- unsteadiness in walking; rarely, gait apraxia
- resistance to passive movements of the limbs - paratonia
Related to paracentral lobule:
- incontinence of urine or faeces - cortical disinhibition
Orbital surface:
- unilateral or bilateral anosmia
A patient with a frontal lobe space-occupying lesion on one side may cause optic atrophy in one eye, due to compression of the optic nerve, and papilloedema in the other eye, due to secondarily raised intracranial pressure - Foster Kennedy syndrome.
Frontotemporal Dementia
Pick’s Disease
Hemiparesis?
- Hemiparesis is weakness of the whole of one side of the body.
- It may be due to an upper motor neurone lesion deep in the contralateral hemisphere, i.e. involving the internal capsule.
- It is very unlikely that a hemiparesis could be caused by lower motor neurone lesions - it is impossible for it to be caused by a single lower motor neurone lesion.
Frontotemporal Dementia
Pick’s Disease
Monoparesis?
Monoparesis is weakness in just one limb:
- It may be caused by a peripheral cerebral lesion involving the motor cortex on contralateral side and producing upper motor neurone signs in the affected limb.
- It can also be caused by a lower motor neurone lesion.
Frontotemporal Dementia
Pick’s Disease
Jacksonian Epilepsy?
- Jacksonian epilepsy is a partial epileptic seizure that occurs because of a lesion in the primary motor area.
- Such a lesion causes jerking and tonic spasms of the contralateral face and limbs.
- In Jacksonian epilepsy, movement begins at the angle of the face or thumb and index finger and then progressively spreads to the arm, trunk, and then the leg and foot.
