Que peut nous apprendre l’étude du métabolisme cérébral en TEP au 18F-FDG du syndrome de Lance-Adams ?

Abstract

Lance-Adams syndrome, also known as “chronic post-anoxic myoclonus”, is a rare syndrome characterised by intention and action myoclonus following cerebral anoxia, leading to major disability. The cortical or subcortical origin of the myoclonus is still debated. Answering this question would open up new avenues of translational research to gain a better understanding of the pathophysiology of this syndrome and better guide the therapeutic management of patients. In addition to a neurological examination, the initial diagnostic work-up includes a biological work-up, electrophysiological investigations and brain imaging to rule out diGerential diagnoses. Cerebral MRI is the reference imaging technique. In the literature, more than a third of patients have a normal MRI. MRI is used to rule out a vascular cause and to look for atrophy or neuronal damage. Few data are available in the literature on the role of nuclear medicine. To date, 13 cases have been published using 18F-FDG PET and 4 using cerebral perfusion scintigraphy. Abnormalities of cortical and/or subcortical perfusion or metabolism are reported in 65% of cases; they are limited to the neocortex in 23% and aGect the cerebellum in 12% of cases. In this article, we present three patients who underwent cerebral 18F-FDG PET scans for Lance-Adams syndrome with normal MRI. The results of these examinations are discussed and compared with the data found in the literature.