[Does semi-quantitative analysis of FDG-PET have any additional value in the diagnosis of mesial temporal sclerosis?].
The aim of this study was to compare qualitative visual analysis with semi-quantitative analysis in the diagnosis of mesial temporal sclerosis (MTS) using FDG-PET.


METHODS
This study included 21 patients with histopathological confirmation of MTS. FDG-PET visual analysis data were based on clinical reports generated soon after the completion of the scan. FDG-PET images were semi-quantitatively analyzed using regions of interest (ROIs) in 19 slices perpendicular to the longest axis of the temporal lobe. These ROIs divided each temporal lobe into three regions (lateral, inferior and medial). An asymmetry index was calculated for each region.


RESULTS
The visual analysis of the FDG-PET studies demonstrated asymmetric hypometabolism in all patients. All but 1 patient underwent standard lobectomy of the same side described as hypometabolic by the PET report. Using an asymmetry index equal or greater than 9% in at least one of the regions as a threshold, the FDG-PET semi-quantitative analysis showed significant asymmetry in 18 patients. These also matched the side of lobectomy and were confirmed as sclerotic in all but one patient (same patient as above).


CONCLUSIONS
The semi-quantitative analysis did not provide additional information over visual interpretation in this series of patients.
Duarte
P S
PS
Divisão de Medicina Nuclear, Hospital da Universidade da Pensilvânia, Filadélfia, Pensilvânia, USA. paula.duarte@fleury.com.br
Zhuang
H
H
Couturier
O
O
Alavi
A
A
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000378:metabolism / Q000473:pathology; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D013702:Temporal Lobe / Q000000981:diagnostic imaging*; D014055:Tomography, Emission-Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18