Limbic encephalitis with involvement of prefrontal cortices and persistent amnesia.
OBJECTIVE
Most abnormalities on magnetic resonance imaging (MRI) in limbic encephalitis involve the medial temporal lobes and are associated with memory impairment. Recent neuroimaging studies have shown that not only the medial temporal lobes, but also the prefrontal lobes, contribute to cognitive functions.


METHODS
We describe a case of limbic encephalitis with abnormalities in the medial temporal lobes on MRI and decreased accumulation of radionuclide in the prefrontal regions on SPECT.


RESULTS
The patient had persistent retrograde amnesia, particularly affecting remotely acquired memories including public events and autobiographical memories.


CONCLUSIONS
Disruption of the prefrontal-medial temporal circuitry by intense inflammation may have initiated the metabolic changes in the prefrontal cortices, which may exacerbate amnesia.
Kataoka
Hiroshi
H
Department of Neurology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, Japan. hk55@naramed-u.ac.jp
Furiya
Yoshiko
Y
Ueno
Satoshi
S
D000647:Amnesia / Q000209:etiology*; D005260:Female; D006801:Humans; D020363:Limbic Encephalitis / Q000150:complications* / Q000473:pathology* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000473:pathology*; D015899:Tomography, Emission-Computed, Single-Photon