Multimodality Image Post-processing in Detection of Extratemporal MRI-Negative Cortical Dysplasia

Area of Science:

• Neuroimaging
• Epileptology
• Neurosurgery

Background:

• Focal cortical dysplasia (FCD) is a common cause of medically refractory epilepsy.
• Diagnosing MRI-negative FCD presents a significant challenge in presurgical evaluation.
• Advanced imaging post-processing techniques are crucial for identifying the epileptogenic zone.

Purpose of the Study:

• To evaluate the diagnostic performance of individual and combined image post-processing techniques for extratemporal MRI-negative FCD.
• To compare the detection rates of morphometric analysis program (MAP), PET/MRI co-registration, and SPM-PET.
• To correlate imaging findings with stereoelectroencephalography (SEEG) and histopathology.

Main Methods:

• Analysis of 33 patients with histologically proven, MRI-negative FCD undergoing extratemporal operations.
• Application and comparison of MAP, PET/MRI co-registration, and SPM-PET.
• Comparison of identified epileptogenic zones with SEEG and histopathological findings.

Main Results:

• PET/MRI demonstrated the highest detection rate (90.9%) for FCD, particularly for types II and IIA.
• Combined techniques achieved a 97.0% detection rate.
• MAP detected 24.2% and SPM-PET detected 57.6% of lesions.
• 26 out of 33 patients (78.8%) achieved seizure freedom post-surgery.

Conclusions:

• MAP, PET/MRI, and SPM-PET provide complementary information for FCD detection and surgical planning.
• PET/MRI is highly effective for detecting extratemporal MRI-negative FCD.
• These advanced imaging modalities aid in intracranial electrode placement and lesion resection, improving surgical outcomes.