The Role of FDG‐PET in Patients with Epilepsy Related to Periventricular Nodular Heterotopias: Diagnostic Features and Long‐Term Outcome

Abstract

BACKGROUND AND PURPOSE: Periventricular nodular heterotopias (PNHs) are frequently associated with drug-resistant epilepsy (DRE). Although magnetic resonance imaging (MRI) can define the morphological features of PNHs, still there is a need to assess their metabolic activity in order to provide useful information on epileptogenicity and long-term outcome. To that end, we investigated the ability of 18 F-FDG PET to identify seizure onset zone in order to assess the metabolic activity of the ectopic neurons and to provide prognostic information on the postsurgical outcome. METHODS: Sixteen patients (6 men and 10 women; ranging between 24 and 53 years of age) with PNHs-related DRE were evaluated. All patients underwent clinical evaluation, Stereo-electroencephalogram (SEEG), brain MRI, and 18 F-FDG brain PET/CT. PET images were superimposed on the patient-specific 3-dimensional-brain MRI. The metabolic activity of each nodule and of their cortex was visually and semiquantitatively assessed. The outcome after intervention was assessed in all patients using Engel classification. RESULTS: Thirty-one heterotopic sites were identified. Twenty-one of 23 nodules with detectable electric activity on SEEG were identified by PET (91.3%), while 5 of 8 of nodules without electric activity showed no metabolism on PET (62.5%). Overall, the concordance between SEEG and FDG-PET was 26/31 (83.9%). Furthermore, cortical metabolic alterations were depicted, correlating with epileptogenic areas. A favorable postsurgical outcome was reported in 13 patients (81.3%). The presence of a hypometabolic nodule significantly correlated with a worse outcome after surgical therapy (P = .036). CONCLUSIONS: In PNHs-related epilepsy, FDG-PET more accurately identifies epileptogenic foci, which aids surgical planning and in postoperative seizure control.

The analysis of 18 F‐FDG PET/MRI, electroencephalography, and semiology in patients with gray matter heterotopia: A pilot study

“…12,23,25,26 However, there is scarce and, to some extent, conflicting evidence regarding the utility of 18 F-FDG PET/CT in GMH patients. 24,27 For instance, Mirandola et al 27 observed no correlation between PET/CT and SEEG, while Popescu et al 24 documented that PET/CT had high sensitivity in detecting seizure onset zone and had a high correlation with SEEG. Popescu et al 24 concluded that MRI and 18 F-FDG PET/ CT contributed to detecting EZ, determining the place of invasive electrodes, and increasing the chance of seizure freedom after epilepsy surgery.…”

“…24,27 For instance, Mirandola et al 27 observed no correlation between PET/CT and SEEG, while Popescu et al 24 documented that PET/CT had high sensitivity in detecting seizure onset zone and had a high correlation with SEEG. Popescu et al 24 concluded that MRI and 18 F-FDG PET/ CT contributed to detecting EZ, determining the place of invasive electrodes, and increasing the chance of seizure freedom after epilepsy surgery. The present work furthered the latter study by using a hybrid PET/MRI scan and mirroring their findings by showing the yields of 18 F-FDG PET/MRI.…”

“…14,[33][34][35][36][37] Few of the aforementioned studies and case series investigated the clinical relevance of the metabolism of the heterotopic nodules. For instance, Popescu et al 24 found an inverse correlation between the presence of hypometabolic nodules and postsurgical outcomes. Further, both Popescu et al 24 and Bund et al 32 suggested that 18 F-FDG PET/MRI patterns of the nodules might aid in decision-making in placing electrodes before SEEG.…”

“…of the right precentral gyrus since this area was normal in all patients. 24 GMHs were classified as follows: (1) 2 and 3, respectively. Table S2 is the survey of 18 F-FDG PET findings of GMH patients with epilepsy reported in the literature.…”

Deep Learning-Based Positron Emission Tomography Molecular Imaging in the Assessment of Cognitive Dysfunction in Patients with Epilepsy

“…In recent years, the incidence of cerebrovascular disease, dementia, and neurodegenerative diseases has increased with the aging of the Chinese population. Moreover, the incidence of epilepsy in the elderly shows an upward trend [2]. According to the location of abnormal discharge of neurons and the range of discharge, the main clinical manifestations are the different dysfunctions, including different motor, sensory, cognitive, and autonomic nerve [3].…”