Improving surgical outcome with electric source imaging and high field magnetic resonance imaging

Author(s)

Saute, Ricardo Lutzky ^[1] ; Peixoto-Santos, Jose Eduardo ^[2] ; Velasco, Tonicarlo R. ^[1] ; Leite, Joao Pereira ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Neurosci & Behav Sci, Ave Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Fed Sao Paulo, Paulista Sch Med, Dept Neurol & Neurosurg, Discipline Neurosci, Sao Paulo - Brazil

• Document type: Journal article
• Source: SEIZURE-EUROPEAN JOURNAL OF EPILEPSY; v. 90, n. SI, p. 145-154, AUG 2021.
• Web of Science Citations: 1

Abstract

While most patients with focal epilepsy present with clear structural abnormalities on standard, 1.5 or 3 T MRI, some patients are MRI-negative. For those, quantitative MRI techniques, such as volumetry, voxel-based morphometry, and relaxation time measurements can aid in finding the epileptogenic focus. High-field MRI, just recently approved for clinical use by the FDA, increases the resolution and, in several publications, was shown to improve the detection of focal cortical dysplasias and mild cortical malformations. For those cases without any tissue abnormality in neuroimaging, even at 7 T, scalp EEG alone is insufficient to delimitate the epileptogenic zone. They may benefit from the use of high-density EEG, in which the increased number of electrodes helps improve spatial sampling. The spatial resolution of even low-density EEG can benefit from electric source imaging techniques, which map the source of the recorded abnormal activity, such as interictal epileptiform discharges, focal slowing, and ictal rhythm. These EEG techniques help localize the irritative, functional deficit, and seizure-onset zone, to better estimate the epileptogenic zone. Combining those technologies allows several drug-resistant cases to be submitted to surgery, increasing the odds of seizure freedom and providing a must needed hope for patients with epilepsy. (AU)

• FAPESP's process: 17/03739-8 - Histopathological correlates of magnetic resonance imaging in patients with drug-resistant epilepsies
• Grantee: José Eduardo Peixoto Santos
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 16/17882-4 - Drug-resistant epilepsies: diagnostic challenges, associated comorbidities and new experimental approaches
• Grantee: João Pereira Leite
• Support Opportunities: Research Projects - Thematic Grants