Recovery from Transient Global Amnesia Following Restoration of Hippocampal and Fronto–Cingulate Perfusion

Abstract

A patient who suffered a transient global amnesia (TGA) attack underwent regional cerebral blood flow (rCBF) SPECT imaging and neuropsychological testing in the acute phase, after one month and after one year. Neuropsychological testing in the acute phase showed a pattern of anterograde and retrograde amnesia, whereas memory was within age normal limits at follow up. SPECT data were analysed with a within subject comparison and also compared with those of a group of healthy controls. Within subject comparison between the one month follow up and the acute phase detected increases in rCBF in the hippocampus bilaterally; further rCBF increases in the right hippocampus were detected after one year. Compared to controls, significant hypoperfusion was found in the right precentral, cingulate and medial frontal gyri in the acute phase; after one month significant hypoperfusion was detected in the right precentral and cingulate gyri and the left postcentral gyrus; after one year no significant hypoperfusion appeared. The restoration of memory was paralleled by rCBF increases in the hippocampus and fronto-limbic-parietal cortex; after one year neither significant rCBF differences nor cognitive deficits were detectable. In conclusion, these data indicate that TGA had no long lasting cognitive and neural alterations in this patient.

Transient global amnesia: a study with Tc-99m ECD SPECT shortly after symptom onset and after recovery

“…Hypoperfused lesions detected on initial scans were all resolved on follow-up scans. This result is consistent with previous reports (19,22,23). Interestingly, a few articles have demonstrated marginal memory impairment after recovery from TGA attack (21).…”

Transient Global Amnesia: A Diffusion and Perfusion MRI study

“…Although no specific treatment is needed, the underlying pathophysiology of this disease is uncertain. An ischemic mechanism is considered to be one of the possible causes, 4‐7 which has been supported by blood flow analysis 8‐10 in various parts of the brain 7,11 . Other theories included epilepsy, 12‐15 migraine, 1‐3 or underlying vulnerability of the memory network 16,17 .…”

Amnesia global transitoria y su relación con factores psicológicos y neuropsicológicos

“…Los resultados de estos estudios parecen apuntar hacia la existencia de acuerdo en la presencia de inestabilidad afectiva como un factor de vulnerabilidad para presentar estrés psicológico. Sin embargo, genética, factores emocionales y cognitivos y su interacción, ejercerán influencia de manera diferencial en la forma en que cada individuo es capaz de enfrentarse a situaciones estresantes [11].Junto con esto, el hecho de poseer una historia de trastornos psicopatológicos muestra que estos pacientes llegan a experimentar niveles de ansiedad y depresión mayores dos semanas antes del episodio [12] durante el episodio, y que incluso pueden llegar a tener relevancia en la recuperación [13]. Aquellos pacientes que muestran síntomas de ansiedad y depresión especialmente llamativos en la fase aguda, exhiben alteraciones mnésicas mayores [14].…”

“…De todo lo mencionado se extrae la existencia de ciertas áreas cerebrales afectadas en el AGT, principalmente el área anterior del hipocampo ligada a la codificación y recuperación de la memoria episódica, aspecto clave en la neuropsicología del AGT [13].…”

“…Los estudios neuropsicológicos en el AGT han encontrado alteraciones de la memoria declarativa (explícita). El componente de memoria episódica es el que se encuentra afectado en estos casos de forma importante, de manera más severa en su modalidad anterógrada y en la retrógrada con menos fuerza [13].…”