What are the bad risks if my baby has extra fluid in her head?

Depends. The primary source of extra fluid in the head is the normal spinal fluid produced in the ventricles of the brain but blocked from its normal distribution & absorption pathway over the cerebral hemispheres. If unable to travel out, the fluid builds up pressure & distorts the brain. Fluid pockets could also occur if a stroke led to loss of brain substance & spinal fluid filled the void.Surgery helps.