[Positron emission tomography: which indications, which benefits?].

Area of Science:

• Neurology
• Nuclear Medicine
• Epileptology

Background:

• Positron emission tomography (PET) with (18)fluoro-desoxy-glucose ((18)FDG) is a standard tool in presurgical epilepsy workup.
• It assesses interictal metabolism, complementing MRI in drug-resistant partial epilepsies.

Purpose of the Study:

• To evaluate the role of (18)FDG-PET in identifying epileptogenic zones.
• To assess the correlation between PET findings, MRI, and surgical outcomes in epilepsy.

Main Methods:

• Utilized (18)FDG-PET to measure interictal glucose metabolism in patients with epilepsy.
• Coregistration and superimposition of PET on MRI were employed to enhance spatial accuracy.

Main Results:

• In medial temporal lobe epilepsy (MTLE) with hippocampal sclerosis, (18)FDG-PET detects hypometabolism in 70-90% of cases, often larger than MRI lesions.
• Hypometabolism detected by PET correlates with surgical outcomes and cognitive function.
• PET can identify subtle abnormalities and guide invasive monitoring in MRI-negative cases.

Conclusions:

• Interictal (18)FDG-PET is valuable for localizing the epileptogenic zone, especially in MTLE and MRI-negative epilepsies.
• PET findings improve surgical planning and outcomes by delineating the extent of hypometabolism beyond structural lesions.
• Enhanced sensitivity is achieved through PET-MRI coregistration, benefiting both children and adults.