Summary about Disease
Transient global amnesia (TGA) is a sudden, temporary episode of complete memory loss with confusion and disorientation. The individual can't recall recent events or where they are, even though they remain conscious, alert, and often able to carry on complex tasks. It's a rare condition and, by definition, resolves within 24 hours, leaving no lasting neurological damage. While frightening for the individual and observers, TGA is generally considered benign.
Symptoms
Sudden onset of profound memory loss, primarily affecting recent events (anterograde amnesia) and memories from the past (retrograde amnesia).
Repetitive questioning (e.g., "What am I doing here?", "Why am I asking these questions?").
Confusion about time, place, and identity.
Preserved personal identity (patient knows who they are, what their name is).
Normal cognitive functions besides memory loss (e.g., language, reasoning, attention, motor skills, recognition of familiar people).
Absence of other neurological symptoms (weakness, paralysis, seizures).
Anxiety and distress related to memory loss.
Causes
The exact cause of TGA is not fully understood, but several factors have been implicated:
Migraines: A history of migraines is associated with an increased risk of TGA.
Blood flow problems: Temporary disruption of blood flow to the brain, particularly to areas involved in memory, such as the hippocampus, is suspected.
Venous congestion: Increased pressure in the veins of the brain.
Triggers: Specific events or activities sometimes precede TGA episodes, including:
Strenuous physical activity.
Emotional stress.
Pain.
Minor head trauma.
Medical procedures.
Sudden immersion in cold or hot water.
Epilepsy: Very rarely, TGA-like symptoms may be associated with certain types of seizures.
Medicine Used
There is no specific medication to treat transient global amnesia itself. Treatment focuses on:
Treating underlying conditions: If a cause such as migraine is identified, medications for migraine management may be prescribed.
Symptomatic relief: Anti-anxiety medications may be used in some cases to reduce the patient's distress.
Observation: Primarily, it involves close monitoring to ensure other conditions like stroke or seizure are ruled out.
Is Communicable
No, transient global amnesia is not a communicable disease. It is not caused by an infectious agent and cannot be spread from person to person.
Precautions
There are no specific precautions to prevent TGA, as the exact cause is unknown and it's usually a one-time event. However, managing known risk factors might be beneficial:
Migraine Management: Individuals with a history of migraines should work with their doctor to manage their migraines effectively.
Stress Reduction: Employing stress-reduction techniques.
Healthy Lifestyle: Maintaining a healthy lifestyle through regular exercise, a balanced diet, and adequate sleep is generally recommended.
How long does an outbreak last?
TGA is not an outbreak. An episode of TGA, by definition, lasts no more than 24 hours. The memory returns gradually, and the individual usually recovers fully.
How is it diagnosed?
Diagnosis of TGA is based on clinical criteria:
Observed episode: A reliable witness observes the memory loss.
Anterograde amnesia: Inability to form new memories.
Retrograde amnesia: Loss of memory for recent events.
Clear consciousness: The patient is alert and aware during the episode.
Preserved identity: The patient knows who they are.
Normal cognitive function: No other significant neurological deficits (e.g., weakness, language problems).
Exclusion of other conditions: No evidence of stroke, seizure, or other neurological disorders.
Resolution within 24 hours. Diagnostic tests that may be performed to rule out other conditions include:
Neurological examination: To assess overall neurological function.
MRI: To look for evidence of stroke, tumors, or other brain abnormalities.
CT scan: Another imaging technique to rule out structural problems in the brain.
EEG (electroencephalogram): To rule out seizure activity.
Blood tests: To check for infections or other medical conditions.
Timeline of Symptoms
Onset: Sudden, typically witnessed by someone else.
Initial Phase: Profound anterograde and retrograde amnesia, repetitive questioning, confusion.
Duration: The acute phase lasts for a variable period, up to 24 hours.
Recovery: Memory gradually returns. Initially, there may be patchy memory for the period of the episode.
Long-Term: Most people regain full memory function and do not experience recurrent episodes. A small percentage may have another episode in the future. A permanent memory gap for the events of the TGA episode usually remains.
Important Considerations
Rule out other conditions: It is crucial to rule out more serious conditions, such as stroke or seizure, that can mimic TGA symptoms.
Reassurance: The person experiencing TGA and their family or caregivers need reassurance that the condition is usually temporary and benign.
Supervision: During the episode, the person with TGA should be supervised to prevent falls or other injuries due to confusion and memory loss.
Follow-up: After an episode of TGA, follow-up with a neurologist is recommended to evaluate for possible underlying causes and provide guidance.
Driving: People should avoid driving until their memory has fully recovered and they have been cleared by a doctor.