BACKGROUND

Magnetic resonance imaging (MRI) has gained increased diagnostic utility for patients with transient global amnesia (TGA), particularly for unwitnessed events or those with diagnostic uncertainty based on clinical grounds.

The objectives are first, to determine the demographic and comorbid conditions of TGA patients; second, to determine the percentage of MRI diffusion weighted imaging (MRI DWI) hippocampal lesions, their time relationship from symptom onset, and their morphological characteristics; and lastly, to determine the dementia visual rating scale scores on neuroimaging for these patients.

A total of 20 TGA patients in a tertiary hospital from 2018 to 2022 were included in this retrospective study, and their medical records and neuroimaging were reviewed.

TGA patients had a mean age of 61.4 years and a female predominance. Prevalent comorbid conditions include hypertension, dyslipidemia, and diabetes, and the majority were discharged with antithrombotic medications. An emotionally triggering event was identified in 15% (n = 3). Mean symptom onset-to-scan time was 8.33 h, and one patient (detection rate of 5%) who underwent neuroimaging after 21.7 h demonstrated typical punctate hippocampal DWI hyperintensity. None exhibited significant cortical atrophy.

TGA patients showed female predominance, occurring mostly within the 5th–6th decade, with a moderate prevalence of vascular risk factors and absence of significant cerebral atrophy based on the Dementia Visual Rating Scales. A conventional MRI protocol yielded a 5% detection rate with a delay of 21 h from symptom onset. Hence, in a resource-limited setting such as the Philippines, it may be suggested, with limited evidence, that performing the procedure in TGA patients when the event is unwitnessed or uncertain could be reasonable, as correctly diagnosing TGA has therapeutic implications. Further studies may investigate prospectively the diagnostic utility of MRI, neuropsychological profile, and estimate cardiovascular and cognitive deterioration risk.

BACKGROUND AND PURPOSE: During transient global amnesia (TGA), selective impairment of episodic memory is assumed to occur due to alteration in the neuronal network between the hippocampus and parietooccipital cortices that also include a hub for smooth pursuit (SP) eye movements. This study aimed to determine whether SP is impaired during TGA, and to identify any anatomical and functional linkage present between the oculomotor and memory systems. METHODS: Within a median of 1.0 day of TGA, horizontal SP was evaluated in 145 patients with a target moving at peak velocities of 10°/s and 20°/s. The average SP gains of patients were compared with those of the age-matched controls. RESULTS: The patients with TGA showed lower SP gains in both directions for both peak target velocities. While the normal controls showed symmetric SP in the rightward and leftward directions, in the TGA patients the SP gain was lower during rightward than leftward SP regardless of bilaterality or the side of the lesions. CONCLUSIONS: The cortical regions processing information about visual motion appeared to be affected during or soon after an amnestic episode of TGA, and more so in the right hemisphere. This means that disturbed processing of dynamic visual information may be related to the impaired spatial orientation observed during TGA.
Amnesia, Transient Global ; Eye Movements ; Hippocampus ; Humans ; Memory ; Memory, Episodic ; Neurons ; Pursuit, Smooth

No abstract available.
Amnesia, Transient Global* ; Posterior Leukoencephalopathy Syndrome*

No abstract available.
Amnesia, Transient Global ; Gastroscopy

We report two patients who complained of transient anterograde amnesia and repetitive questioning, that developed after taking zolpidem and lasted for several hours. The clinical manifestations of these patients fulfill the clinical criteria for transient global amnesia (TGA). The typical clinical manifestation of TGA following the consumption of zolpidem suggests a possible relationship associated with its drug mechanism.
Amnesia, Anterograde ; Amnesia, Transient Global ; Humans

No abstract available.
Amnesia, Transient Global* ; Humans ; Writing*

No abstract available.
Amnesia, Transient Global* ; Infarction*

No abstract available.
Amnesia, Transient Global* ; Incidence* ; Korea* ; Seasons*

BACKGROUND: The dot-like hippocampal signal intensity in diffusion-weighted MR images is well-known as a characteristic imaging feature in transient global amnesia, a neurological syndrome in which sudden forward-and-backward memory loss occurs that is slowly recovered within 24 hours. We here report on patients with this dot-like hippocampal hyperintensity who did not present with anterograde amnesia except for headaches. CASE REPORT: Two women without a specific medical history presented with sudden-onset headaches on the same day. Neither had any trauma or infection history before the symptom or any sudden emotional or postural changes. Brain MRI showed tiny hippocampal high signal intensity on diffusion-weighted images (DWI). CONCLUSIONS: Dot-like hippocampal lesions seen on DWI may be present without memory impairment, and more studies are needed to determine whether there is any association with headache as in this case.
Amnesia, Anterograde ; Amnesia, Transient Global* ; Brain ; Diffusion* ; Female ; Headache* ; Hippocampus ; Humans ; Magnetic Resonance Imaging ; Memory ; Memory Disorders

BACKGROUND AND PURPOSE: Transient global amnesia (TGA) is a stereotypic condition characterized by anterograde and retrograde amnesia that typically resolves within 24 hours. The pathophysiology of TGA is still unclear. We noted that patients hospitalized with TGA tend to appear in seasonal clusters, and decided to investigate this phenomenon. METHODS: Every patient with acute presentation of amnesia at our medical center is hospitalized for observation and evaluation. We reviewed the monthly occurrence of TGA in our patient population between 2000 and 2014, and compared this to non-TGA hospitalizations during the same time period. RESULTS: During the analysis period, 154 patients who met the criteria for TGA were hospitalized, as well as 259,007 non-TGA hospitalizations. The annual occurrence of TGA ranged from 5 to 16 hospitalizations. There were 91 TGA events in women and 63 in men, in subjects aged 62.8±10.6 years (mean±SD). The incidence was maximal during December [odds ratio (OR)=2.83, 95% confidence interval (CI)=1.20–6.67] and March (OR=2.77, 95% CI=1.17–6.56), and minimal from April to August. The incidence exhibited an increase followed by a decrease from October to February. A seasonal trend was observed as well, with incidence peaks occurring in winter (OR=1.82, 95% CI=1.12–2.96) and spring (OR=1.80, 95% CI=1.10–2.94). CONCLUSIONS: Our findings suggest that the incidence of TGA exhibits seasonal variations. This observation may help to improve the understanding of the pathophysiology underlying TGA.
Amnesia ; Amnesia, Retrograde ; Amnesia, Transient Global* ; Female ; Hospitalization ; Humans ; Incidence* ; Male ; Seasons*