What is the diagnosis and treatment for Deja Vu (already seen) phenomenon?

Déjà Vu Phenomenon: Diagnosis and Treatment

Déjà vu is primarily a benign phenomenon in healthy individuals but can be a warning sign of temporal lobe epilepsy when persistent or accompanied by specific clinical features. 1

Diagnosis

Definition and Prevalence

• Déjà vu ("already seen") is the feeling of having already witnessed or experienced a current situation, despite the exact circumstances of the prior encounter being unclear
• Extremely common in the general population:
  • Up to 97% of people experience it at least once in their lifetime 2
  • 67% experience it regularly 2

Clinical Classification

Déjà vu can be categorized into three types:

1. Non-ictal déjà vu (in healthy individuals)

   • Prevalence: 74% of healthy individuals 3
   • Usually brief, infrequent, and not associated with other symptoms

2. Ictal déjà vu (during epileptic seizures)

   • Prevalence: 22% of epilepsy patients 3
   • Often a warning sign (aura) of temporal lobe epilepsy
   • Key distinguishing features:
     • Higher frequency of occurrence
     • Longer duration
     • Associated with fatigue and concentrated activity
     • Often accompanied by:
       • Derealisation
       • Olfactory/gustatory hallucinations
       • Physical symptoms (headaches, abdominal sensations)
       • Fear 4

3. Interictal déjà vu (between seizures in epilepsy patients)

   • Prevalence: 62% of epilepsy patients 3

Diagnostic Approach

When a patient reports déjà vu experiences, evaluate for:

1. Frequency and duration

   • Epileptic déjà vu occurs more frequently and lasts longer than physiological déjà vu 4

2. Associated symptoms

   • Presence of derealisation, olfactory/gustatory hallucinations, physical symptoms, or fear suggests epileptic origin 4

3. Temporal pattern

   • Rising sensation from abdomen accompanying déjà vu may suggest epileptic aura 1
   • Persistent déjà vu, especially in adolescents, warrants investigation for temporal lobe epilepsy 5

4. Neurological examination

   • Look for other signs of temporal lobe dysfunction

Treatment

Treatment depends on the underlying cause:

For Benign Non-ictal Déjà Vu

• Reassurance that this is a common, normal phenomenon
• No specific treatment required
• Education about the nature of déjà vu as a memory phenomenon

For Epileptic Déjà Vu (Ictal)

1. Antiepileptic medications

   • First-line treatment for temporal lobe epilepsy with déjà vu as an aura
   • Options include carbamazepine, lamotrigine, levetiracetam, or other anticonvulsants

2. Surgical intervention

   • Consider in medication-resistant cases
   • Temporal lobectomy may be indicated when déjà vu is part of refractory temporal lobe epilepsy

For Déjà Vu Associated with Psychiatric Conditions

• Déjà vu can be associated with anxiety disorders and depersonalization/derealization disorder 2
• Treatment should target the underlying psychiatric condition:
  • Cognitive-behavioral therapy
  • Appropriate psychiatric medications

Special Considerations

In Children and Adolescents

• Persistent déjà vu in young people should raise suspicion for temporal lobe epilepsy 5
• Young patients can describe déjà vu experiences in detail, allowing for earlier diagnosis

In Post-Traumatic Cases

• Déjà vu can occur after traumatic brain injury
• May require more intensive treatment and monitoring

Neurobiological Mechanism

• Likely involves faulty activity in the parahippocampal gyrus and its neocortical connections 6
• The temporal region appears to be the origin of déjà vu phenomena in both healthy individuals and those with neurological conditions 2

Clinical Pitfalls to Avoid

1. Dismissing persistent déjà vu as merely a common experience without considering epilepsy
2. Missing associated symptoms that might indicate epileptic origin
3. Failing to distinguish between benign and pathological forms of déjà vu
4. Not recognizing that déjà vu can be an early warning sign of temporal lobe epilepsy, especially in young patients

Remember that while déjà vu is usually benign, its persistent occurrence with distinctive features warrants neurological evaluation to rule out temporal lobe epilepsy.