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She was slow in learning since childhood, and was a case of delayed milestones, on MR scan mild right medial temporal atrophy
found. Most probably she is suffering from mental retardation. It may occur due to a number of reasons and one is what MR scan is showing. Second reason may be due to abnormal electrical discharges in brain since birth, as in a lot of children with Absence Seizures, due to undetected seizures chronic damage to brain structures occurs which later start manifesting as mental retardation.
So as per my advise kindly get her EEG done to rule out any focal electrical discharge.
Secondly visit a good Psychiatrist
to take expert opinion about her MR.
Regarding treatment, I would like to tell you that the damage what has occurred is not reversible, best you can do is to admit her in special children school or train her in some life skill training so that her vocational rehabilitation
Thanks Take Care