Transient Global Amnesia (TGA)

1. TRANSIENT GLOBAL AMNESIA
(TGA)
AdeWijaya, MD – May 2018

2. Introduction
■ Transient global amnesia (TGA) is a temporary, anterograde amnesia with an acute
onset that usually occurs in middle-aged and older individuals.
■ Resolved within 24 hours
■ Firstly described in literature by Bender also Guyot and Courjon in 1956.
Owen D, Paranandi B, Sivakumar R, Seevaratnam M. Classical diseases revisited: transient global amnesia. Postgraduate Medical Journal. 2007;83:236-9.
Nehring SM, Dulebohn SC. Transient global amnesia.

3. Papez Circuit
for Short-term Memory
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.

4. Risk Factors
■ Strenuous activity
■ High-stress events
■ Coitus
■ Valsava maneuver
■ Migraines
■ Previous heart disease
■ Dyslipidemia
Nehring SM, Dulebohn SC. Transient global amnesia.

5. Etiology
■ Unproven
■ Vascular congestion was considered and is still one of the leading hypotheses
Nehring SM, Dulebohn SC. Transient global amnesia.

6. Epidemiology
■ The incidence ofTGA is about 3,4-10,4/100,000 per year in the general population.
■ In individuals aged 50 and older, the incidence increases to 23.5 to 32/100,000 per
year.
■ 40-80 years old of age (mean: 61)
■ No gender difference
■ 20 minutes – 20 hours (mean: 5,7 hours)
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).
Nehring SM, Dulebohn SC. Transient global amnesia.
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.

7. Pathophysiology
■ Arise from the hippocampus, particularly the CA-1 and Sommer sector, and
mediobasal temporal lobe (Watershed area).
Vascular
Migraine
Epileptic
Venous flow disturbances or
focal arterial ischemia
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.
Nehring SM, Dulebohn SC. Transient global amnesia.
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).

8. Clinical Presentation
■ Acute onset of several hours of memory loss
■ Repetitive questioning and have no recall
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.
Nehring SM, Dulebohn SC. Transient global amnesia.
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).

9. Evaluation
■ Vital signs
■ Lab: toxicology, alcohol, glucose, electrolytes
■ EEG
■ CT/MRI: May show some degree of restricted diffusion on the DWI sequence on one or
both hippocampi.
■ SPECT/PET
■ Doppler: Internal jugular venous flow reversal (IJVFR) and internal jugular vein valve
incompetency (IJVVI)
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).
Nehring SM, Dulebohn SC. Transient global amnesia.

10. Diagnostic Algorhytm
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.

11. Differential Diagnosis
■ Stroke /TIA
■ Epilepsy
■ Syncope
Nehring SM, Dulebohn SC. Transient global amnesia.
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).

12. Treatment & Prognosis
■ Intravenous thiamine
■ Supportive
■ Good prognosis
■ 2-30 % reccurence rate
Arena JE, Rabinstein AA. Transient global amnesia. InMayo Clinic Proceedings 2015 Feb 1 (Vol. 90, No. 2, pp. 264-272). Elsevier.
Nehring SM, Dulebohn SC. Transient global amnesia.
PEREANU M. TRANSIENT GLOBAL AMNESIA. Acta Medica Transilvanica. 2016 Mar 1;21(1).

13. Summary
■ Not a rare entity
■ Diagnosis of exclusion
■ No specific treatment
■ Good prognosis