Alessandro Dinoto1, Marta Cheli2, Miloš Ajčević2,3, Franca Dore4, Carmelo Crisafulli4, Maja Ukmar5, Arianna Sartori2, Paolo Manganotti2. 1. Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Strada di Fiume 447, 34149, Trieste, Italy. alessandro.dinoto@hotmail.it. 2. Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Strada di Fiume 447, 34149, Trieste, Italy. 3. Department of Engineering and Architecture, University of Trieste, Via Alfonso Valerio, 10, 34149, Trieste, Italy. 4. Unit of Nuclear Medicine, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Strada di Fiume 447, 34149, Trieste, Italy. 5. Radiology Unit, Department of Medicine, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Strada di Fiume 447, 34149, Trieste, Italy.
Abstract
BACKGROUND: Autoimmune limbic encephalitis (LE) is a neurological condition characterized by seizures and cognitive dysfunction. Fluorine-18 fluorodeoxyglucose (18F-FDG-PET) has recently proved to be an important diagnostic tool in this condition since it may highlight brain metabolism abnormalities in a very early stage of the disease. Two main 18F-FDG-PET patterns have been described: the mixed hypermetabolic/hypometabolic and the neurodegenerative one. Arterial spin labeling (ASL) is an MRI technique showing brain perfusion, rarely used in autoimmune neurological conditions. The aim of the present study was to study patients with LE with both techniques, in order to compare their results. METHODS: Two patients with LE underwent to 18F-FDG-PET and ASL MRI scans using the pseudo-continuous arterial spin labeling (PCASL) technique. Areas of altered perfusion and metabolism were analyzed by visual inspection, and findings were compared between the two techniques. RESULTS: In the first patient, a relapsing LGI-1 LE, right hippocampal hypermetabolism was detected by 18F-FDG-PET (mixed hypermetabolic/hypometabolic pattern), while ASL MRI showed right hippocampal increased perfusion. In the second patient, a seronegative LE, 18F-FDG-PET scan detected a left hemispheric hypoperfusion (neurodegenerative pattern) and ASL MRI yielded similar results. The two 18F-FDG-PET patterns of altered metabolism were similarly detected by ASL imaging. CONCLUSION: ASL and 18F-FDG-PET findings are strongly concordant in LE. ASL imaging was able to detect the two main 18F-FDG-PET patterns previously described in patients with LE.
BACKGROUND: Autoimmune limbic encephalitis (LE) is a neurological condition characterized by seizures and cognitive dysfunction. Fluorine-18 fluorodeoxyglucose (18F-FDG-PET) has recently proved to be an important diagnostic tool in this condition since it may highlight brain metabolism abnormalities in a very early stage of the disease. Two main 18F-FDG-PET patterns have been described: the mixed hypermetabolic/hypometabolic and the neurodegenerative one. Arterial spin labeling (ASL) is an MRI technique showing brain perfusion, rarely used in autoimmune neurological conditions. The aim of the present study was to study patients with LE with both techniques, in order to compare their results. METHODS: Two patients with LE underwent to 18F-FDG-PET and ASL MRI scans using the pseudo-continuous arterial spin labeling (PCASL) technique. Areas of altered perfusion and metabolism were analyzed by visual inspection, and findings were compared between the two techniques. RESULTS: In the first patient, a relapsing LGI-1 LE, right hippocampal hypermetabolism was detected by 18F-FDG-PET (mixed hypermetabolic/hypometabolic pattern), while ASL MRI showed right hippocampal increased perfusion. In the second patient, a seronegative LE, 18F-FDG-PET scan detected a left hemispheric hypoperfusion (neurodegenerative pattern) and ASL MRI yielded similar results. The two 18F-FDG-PET patterns of altered metabolism were similarly detected by ASL imaging. CONCLUSION: ASL and 18F-FDG-PET findings are strongly concordant in LE. ASL imaging was able to detect the two main 18F-FDG-PET patterns previously described in patients with LE.
Authors: C Lapucci; G Boffa; F Massa; D Franciotta; L Castelletti; A Uccelli; S Morbelli; F Nobili; L Benedetti; L Roccatagliata Journal: Eur J Neurol Date: 2019-05-17 Impact factor: 6.089
Authors: Francesc Graus; Maarten J Titulaer; Ramani Balu; Susanne Benseler; Christian G Bien; Tania Cellucci; Irene Cortese; Russell C Dale; Jeffrey M Gelfand; Michael Geschwind; Carol A Glaser; Jerome Honnorat; Romana Höftberger; Takahiro Iizuka; Sarosh R Irani; Eric Lancaster; Frank Leypoldt; Harald Prüss; Alexander Rae-Grant; Markus Reindl; Myrna R Rosenfeld; Kevin Rostásy; Albert Saiz; Arun Venkatesan; Angela Vincent; Klaus-Peter Wandinger; Patrick Waters; Josep Dalmau Journal: Lancet Neurol Date: 2016-02-20 Impact factor: 44.182