Sorry for the delay. I had to rush to perform an emergency surgery, so I could not respond you earlier. I apologize for your wait.
The EEG abnormalities you mentioned can be due to following causes;
1) may not be pathological / may not be associated with a disease process. These are considered as psychomotor variant.
2) temporal lobe epilepsy. Abnormal slow activity is by far the most common EEG manifestation of focal brain dysfunction and is known to be associated with epilepsy.
3) rarely it can be associated with cerebrovascular disorder which in will warrant an MRA (magnetic resonance angiography) for ruling it out. Focal slowing is the most common abnormality associated with focal lesions of any type, like neoplastic, vascular, injury and infectious. It occasionally may be seen in mesiotemporal sclerosis or focal malformations of cortical development.
EEG is a test of cerebral function; hence, for the most part it is nonspecific as to ascertain the exact cause. He would need following investigations to ascertain the cause of his epilepsy and these wave form abnormalities'
1) Epilepsy protocol MRI.
2) MRI of the temporal lobe
3) MRI of malformations of cortical development.
4) SPECT scanning (Single-Photon Emission Computerized Tomography Scanning)
5) Functional MRI.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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