Correlation of neuropsychological and metabolic changes after epilepsy surgery in patients with left mesial temporal lobe epilepsy with hippocampal sclerosis

Abstract

BackgroundEpilepsy surgery often causes changes in cognition and cerebral glucose metabolism. Our aim was to explore relationships between pre- and postoperative cerebral metabolism as measured with 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and neuropsychological test scores in patients with left mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS), who were rendered seizure-free after epilepsy surgery.ResultsThirteen patients were included. All had neuropsychological testing and an interictal FDG-PET scan of the brain pre- and postoperative. Correlations between changes in neuropsychological test scores and metabolism were examined using statistical parametric mapping (SPM). There were no significant changes in the neuropsychological test scores pre- and postoperatively at the group level. Decreased metabolism was observed in the left mesial temporal regions and occipital lobe. Increased metabolism was observed in the bi-frontal and right parietal lobes, temporal lobes, occipital lobes, thalamus, cerebellum, and vermis. In these regions, we did not find a correlation between changes in metabolism and neuropsychological test scores. A significant negative correlation, however, was found between metabolic changes in the precuneus and Boston Naming Test (BNT) scores.ConclusionsThere are significant metabolic decreases in the left mesial temporal regions and increases in the bi-frontal lobes; right parietal, temporal, and occipital lobes; right thalamus; cerebellum; and vermis in patients with left MTLE-HS who were rendered seizure-free after epilepsy surgery. We could not confirm that these changes translate into significant cognitive changes. A significant negative correlation was found between changes in confrontation naming and changes in metabolism in the precuneus. We speculate that the precuneus may play a compensatory role in patients with postoperative naming difficulties after left TLE surgery. Understanding of these neural mechanisms may aid in designing cognitive rehabilitation strategies.Electronic supplementary materialThe online version of this article (10.1186/s13550-018-0385-5) contains supplementary material, which is available to authorized users.

Neuroprotective effect of astaxanthin (ATX) against cognitive impairment on PTZ-induced epileptic seizures in rats and against PTZ-induced neurotoxicity in SH-SY5Y human neuroblastoma cell culture

“…Another excellent treatment modality is epilepsy surgery. As is known surgical resection of focal epileptic lesions may be cause altered cerebral glucose metabolism and postoperatively cognitive, behavioral and psychosocial changes [3][4][5][6] . The brain tissue consumption high oxygen and the antioxidant system is weak, that means brain tissue could be exposed easily to oxidative damage than other tissue types.…”

18F-FDG PET-guided diffusion tractography reveals white matter abnormalities around the epileptic focus in medically refractory epilepsy: implications for epilepsy surgical evaluation

“…Numerous standalone PET and diffusion MRI studies have reported functional and structural alterations in MRE (Henry and Pennell 1998;Knowlton 2006;Focke et al 2008;Lin et al 2008;Thivard et al 2011;James et al 2015;Labate et al 2015;Burneo et al 2015;Sivakanthan et al 2016;Jiang et al 2017;Güvenç et al 2018;Cahill et al 2019), however, very few studies have assessed relationships between FDG-PET and diffusion MRI findings in epilepsy. Similar to our study, one previous report also found microstructural alterations (decreased FA and increased apparent diffusion coefficient) Note: EF localization concordance between AI mapping and the clinical hypothesis is reported in the second column Abbreviations: +, concordant with clinical hypothesis or improved confidence after PET/DTI; ++, PET/DTI improved confidence and indicated that the patient may benefit from an anterior temporal lobectomy; −, discordant with clinical hypothesis or unchanged confidence after PET/DTI in WM adjacent to the epileptic zone identified by FDG-PET hypometabolism (Lippé et al 2012), while another study revealed that metabolic and structural alterations seen using FDG-PET and DTI involve similar brain regions in mesial temporal lobe epilepsy (Aparicio et al 2016).…”

Effect of different physical activity training methods on epilepsy

“…Approximately 30% of PWE continue to have seizures despite AEDs treatment. [2] However, long-term use of these drugs may cause a variety of side effects and the most commonly reported adverse events across all AEDs were drowsiness/fatigue, headache or migraine, gastrointestinal disturbances, dizziness/ faintness, and rash or skin disorders. [3] PWE also experience a high degree of comorbidity.…”