This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
A 15 year old boy had 10–12 partial complex seizures per day inspite of adequate 4 drugs antiepileptic regime. He had a history of repeated high-grade fever in childhood. MRI for epilepsy protocol revealed normal brain scan. What should be the best noninvasive strategy to make a definite diagnosis so that he can be prepared to undergo epilepsy surgery – 
Select and explain. 
A. Interictal scalp EEG, B. Video EEG, C. Interictal 18F–FDg PET., D. Video EEG with Ictal 99m Tc – HMPAO Brain SPECT
D: Video EEG with Ictal 99m Tc – HMPAO Brain SPECT
Answer: D: Video EEG with Ictal 99m Tc – HMPAO Brain SPECT 
Explanation: If localization of epileptic focus is unrevealed on MRI, Ictal SPECT with HMPAO is the most practical and best method. Addition of video EEG further helps in localization of epileptic foci.