My niece,3yrs, has been diagnosed pf mild generalised cerebral atrophy in ct scan...what does this mean?she has been suffering from fever since 10 day

Depends: The answer to your question should come from the doctor who ordered the CT scan. He/she would take in consideration the other symptoms your child has and the index of suspicion he/she had he/she overact he test. There must be other tests done too. And if there is still no answer, your daughter would probably be referred to a neurologist