Application of positron emission computed tomography/magnetic resonance imaging coregistration in improving epileptic foci detection rate of structural intractable epilepsy in children

Abstract

Objective To study the predictive value of magnetic resonance imaging (MRI), positron emission computed tomography (PET) and PET/MRI coregistration in intractable epilepsy of children. Methods A retrospectively analysis was performed based on the surgery data at the Department of Children Epilepsy Center of Peking University First Hospital from September 2015 to March 2016.The clinical data, surgery and follow-up study data, interictal and ictal electroencephalogram, MRI, PET and PET/MRI coregistration data were collected.By comparison with the epileptogenic zone designed by pre-surgical workup, the accuracy of MRI, PET and PET/MRI coregistration in detecting lesion was assessed.In the patients who had no seizure during ≥1 year follow-up, their sensitivity, specificity, positive predictive value, negative predictive value of MRI, PET and PET/MRI coregistration were calculated. Results (1)A total of 62 patients underwent surgery, 30 boys and 32 girls.The average age on epilepsy onset was 2.50 years (2 days-11.70 years), and average age on surgery was 5.10 years old(0.75-15.60 years old). (2)Surgical treatment of 62 cases included the resection of the focal or lobar(32 cases, 51.6%), and the multilobar (16 cases, 25.8%). Hemispherotomy was done in 14 cases (22.6%). During ≥1 year follow-up, seizure outcome was Engel class Ⅰ in 57 cases (91.9%) out of the 62 patients, Engel class Ⅱ to Engel class Ⅳ in 1 case, 3 cases, and 1 case, respectively.(3) Referred to epileptogenic zone designed by presurgical workup, MRI represented 64.5%(40/62 cases) results with accordance, PET and PET/MRI coregistration was 72.5%(45/62 cases) and 85.5%(53/62 cases), respectively, and the difference was significant(χ2=7.25, P=0.03). (4) Based on the patients of Engel class Ⅰ, their sensitivity and specificity were 66.7%, 60.0% in MRI, 75.4%, 60.0% in PET %, and 85.9%, 80.0% in PET/MRI coregistration, respectively.(5)There were 11 non-lesion cases of all focal cortical dysplasia in pathology, and subtle structural abnormalities were de tected in 9 cases by reviewing MRI. Conclusions PET/MRI coregistration can improve lesion detection of intractable epilepsy in children. Key words: Intractable epilepsy; Magnetic resonance imaging; Positron emission computed tomography; Positron emission computed tomography/magnetic resonance imaging coregistration; Epileptogenic zone