Interictal 18F-FDG PET performance of temporal lobe focal cortical dysplasia without MRI abnormalities

Abstract

Objective To evaluate the ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) PET performance of focal cortical dysplasia (FCD) without MRI abnormalities. Methods A total of 47 cases with FCD underwent standard anterior temporal lobectomy (ATL) and hippocampectomy and were confirmed by postoperative pathological findings. Preoperative MRI showed no obvious abnormalities, and ¹⁸F-FDG PET were performed on all of them. Results There were 26 males and 21 females, aged 9-51 years (the mean age was 24.35 years). According to postoperative pathological examinations, there were 33 cases of FCD type Ⅰ (12 cases of type Ⅰa, 8 cases of type Ⅰb and 13 cases of type Ⅰc) and 14 cases of FCD type Ⅱ (10 cases of type Ⅱ a and 4 cases of type Ⅱ b). A total of 45 cases (95.74% ) showed reduced brain metabolism in PET examination, including 37 cases of focal temporal lobe hypometabolism (located in medial temporal lobe, temporal pole and hippocampus, etc.) and 8 cases of multifocal hypometabolism (extensive hypometabolism in anterior and posterior temporal lobe). Conclusions ¹⁸F-FDG PET imaging can be taken as an adjunct diagnostic tool in temporal lobe FCD without MRI abnormalities, so it has important referential value in clinical diagnosis.

DOI: 10.3969/j.issn.1672-6731.2015.10.011