Generally, these patients present with acute onset of several hours of memory loss. They will display repetitive questioning and have no recall of how they got where they are or what they did in the time immediately preceding the onset. Often, the person(s) accompanying the patient will report recent activity such as vigorous exertion, coitus, or severe stress. They will not report a loss of consciousness. They do not lose their self-identity ability.  There are no accompanying neurological deficits or other cognitive deficits.  There will be no history of trauma, and the symptoms will resolve within 24 hours of onset. The presence of active seizures excludes TGA, whether new-onset or chronic.  The symptoms are not present when the patient awakens in the morning but occur later in the day.

Patients will present with no focal neurological deficits but will often not recall how they got to the hospital, that they are in the hospital, or the day's events. They will often not recall people or locations from the past few hours and will feel disoriented as a consequence. Even with visual cues, such as pictures taken during the day, they will have no recollection of the events. They will repeatedly ask the same question, as they forget they just asked the question moments before. The symptoms will begin to improve within hours and memory will slowly, and almost entirely, return over the course of the next 24 hours. Initially, it was thought that total resolution was achieved, but more recent studies suggest there can be some minor residual impairment surrounding the event as well as some subclinical cognitive deficits, even years later. 

The patient should be admitted to a hospital setting until the amnesia resolves. A toxicology screen, alcohol level, and basic labs including glucose and electrolytes should be reviewed. Vitals, including oxygen saturation, should be checked. Because of the possibility of similar presentation with Wernicke encephalopathy, consider administering thiamine. If there are features suggestive of repetitive or seizure-like etiology, EEG could be considered, but it is not routinely recommended. MRI with diffusion-weighted imaging is needed to rule out ischemic stroke, which can have a similar presentation in some cases. However, there is no diagnostic test for TGA; rather, it is a diagnosis of exclusion.

Treatment for TGA is largely supportive. There is no specific therapy for this condition, nor is one necessary. The patient should be examined carefully for any accompanying neurological deficits or evidence of head trauma, both of which would exclude TGA as the diagnosis. The patient should be observed in the hospital until the memory deficit resolves. Consideration should be given for intravenous thiamine. Recurrences, while they do happen, are rare. The patient does not require any restrictions on driving or other activities once the memory deficits resolve.

• Basilar artery thrombosis

• Cardioembolic stroke

• Complex partial seizures

• Lacunar syndrome

• Migraine variants

• Posterior cerebral artery strok

• Syncope

• Temporal lobe epilepsy

TGA is a temporary event and death is very rare. However, the disorder can recur but causes no mortality.

The differential diagnosis when a patient presents with TGA should include intoxication on substance, Wernicke encephalopathy, ischemic stroke, epileptic disorder, transient ischemic attack, toxic encephalopathy, hypoxia, or head injury. However, the confusion is more global in many of these cases and it is not limited to memory loss or there are other presenting symptoms. In seizure-related memory loss, there is usually seizure-like activity prior to the onset, and the memory loss is almost purely retrograde; this differs from TGA which involves anterograde amnesia presenting with minimal retrograde amnesia confined to events surrounding the onset.

The diagnosis and management of TGA are best done with an interprofessional team that consists of a neurologist, internist, radiologist, primary care provider, and nurse practitioner. The problem is that there is a very large differential when patients present with amnesia and consequently the workup is often exhaustive and time-consuming.

The most important disorder that primary clinicians need to rule out include a stroke.

Once TGA is diagnosed, the treatment is supportive. Clinicians need to educate the caregiver and patient that the disorder is benign. The condition resolves spontaneously and rarely recurs. Patients though should be advised to lose weight, discontinue smoking, remain compliant with their medications, abstain from alcohol use and follow up with their primary care provider regularly. The outcome in most patients is good. [9][10](Level V)