Does hippocampal FDG-PET asymmetry predict verbal memory dysfunction after left temporal lobectomy?
The primary aim of this study was to determine whether hippocampal asymmetries in fluorodeoxyglucose (FDG) uptake on preoperative PET scans would predict post-temporal lobectomy verbal memory (VM) decline in patients with left temporal lobe epilepsy. A quantitative asymmetry index (AI) of uptake values within a hippocampal region of interest (ROI) was defined by an automated technique. No statistically significant effect of the hippocampal AI on the outcome measure, the pre- to postsurgical change in Logical Memory Percent Retention, was evident. Post hoc analyses revealed that AIs of the superior and inferior temporal gyri approached significance, however, with relatively greater left-sided preoperative metabolism predicting better VM outcomes. This finding suggests reorganization of function and/or retained function of remaining tissue. Although hippocampal FDG-PET asymmetries did not significantly predict changes in VM, the predictive value of neocortical AIs should be further explored. Automated ROI parcellation provides a feasible tool for use in such investigations.
Leeman
Beth A
BA
Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. bleeman1@bidmc.harvard.edu
Leveroni
Catherine L
CL
Johnson
Keith A
KA
D000328:Adult; D001931:Brain Mapping; D015331:Cohort Studies; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D019788:Fluorodeoxyglucose F18; D007839:Functional Laterality / Q000502:physiology; D006624:Hippocampus / Q000000981:diagnostic imaging*; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000000981:diagnostic imaging / Q000209:etiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography / Q000379:methods; D011612:Psychosurgery / Q000009:adverse effects; D012189:Retrospective Studies; D016896:Treatment Outcome; D014706:Verbal Learning / Q000502:physiology*; D055815:Young Adult
D019788:Fluorodeoxyglucose F18