Frontal Lobe Syndrome

Frontal lobe syndrome (FLS) reflects damage to the prefrontal regions of the frontal lobe. It is characterised by deterioration in behaviour and personality in a previously normal individual.

• Head injury
• Stroke ¹
• Infection
• Neoplasm
• Degenerative disorders, e.g. Pick's disease. Pick's is a type of dementia with histopathological findings of Pick bodies and selective involvement of the frontal and temporal lobes. Many instances of the disorder have a genetic cause.

Prevalence

Found in 19% of people aged ≥85years in one study². There may be significant under-reporting due to the nature of the condition.

Symptoms

Changes are often reported by family as "He's not the father I know", but may be difficult to detect in the surgery during normal conversation.
May be an indication from events such as previous head injury and divorce or loss of job in previously stable individual.
History should include a careful developmental history, trauma history, and social history, including educational and personal achievements, employment history, substance use and abuse history.
Characteristic features are:

• Decreased lack of spontaneous activity - patient feels no desire to do anything and is unable to plan activities, but may have periods of restlessness.
• Loss of attention - patient is disinterested and easily distracted.
• Memory is normal but cannot be bothered to remember.
• Loss of abstract thought e.g. cannot understand proverbs.
• Perseveration - tendency to continue with one form of behaviour when situation requires it to change.
• Change of affect - depending on the nature of the damage to the brain, patient either becomes apathetic and 'flat' or becomes over exuberant and childish or uninhibited with possibly inappropriate sexual behaviour.

Signs

Mini-mental state test does not measure frontal lobe damage properly.
The following are more accurate³:

• Go-no go
  • Tell patient to hold up two fingers if you hold up one and vice versa.
  • Give it 10 attempts.
  • Typically patient with FLS will copy you (echopraxia).
• Visual grasp
  • Hold your hands at the side of the patient's eyes and ask him to fix his eyes on your nose.
  • Check lateral vision by wiggling fingers.
  • Tell patient to move his eyes AWAY FROM hand with wiggling fingers.
  • FLS patient may not be able to do this if there is damage in orbital cortex.
• Letter fluency
  • Ask patient to say as many different words beginning with 'F' in one minute (no proper names).
  • Normally should expect patient to produce at least 8.
• Motor test
  • Perseveration can be shown by asking patient to perform series of 3 movements; make fist, lay palm on desk and then place side of hand on desk.

Demonstrate then observe.
'Neglect' is most common after lesions of the right hemisphere involving either the right parietal lobe or the right frontal lobe. Patients with right-sided brain lesions typically neglect the left hemispace. This can be assessed by asking the patient to draw or read. Patients may neglect the left half of the drawing or leave off the left half of words (neglect dyslexia).

• Alzheimer's disease
• Apraxia
• Aphasia
• Depression

• Check B₁₂ levels, thyroid function, serology for syphilis and antinuclear antibodies.
• Consider MRI/CT if possibility of tumour.

Non-Drug

General supportive care.

• As patients may have lost their inhibitions or appreciation of danger, a high level of supervision may be required.
• If the patient can be supported at home, visiting assistance could be sought from physiotherapists, occupational, and/or speech therapists.
• Respite care may be needed.
• Assessment by a social worker may also be helpful.

Drug

The therapies used in Alzheimer's dementia are not of use.

• Patients with severe injuries or lesions may be severely disabled in a way that their carers may not recognize or appreciate.
• Personal responsibility is frequently affected, even in the absence of gross neurological changes.

This depends on the underlying pathology.