Wally, Your medication needs can and usually do change quite dramatically after surgery.
MKane perhaps it's worth seeing your neurologist and requesting an MRI to more precisely locate the electrodes and for him and the radiologist to confirm whether or not they're in the optimal position?
Taking the same amount of meds as pre op doesn't seem right.
I had to end up taking the same amount of levodopa (1200mg/day) as pre op for 5 months post bilateral DBS as one side had the electrode 2mm away from the optimal position.
When it was repositioned I went to no medication whatsever.
I now take a fraction of medication than what I took before the repositioning and find my medication needs have changed enormously from then in my response to them as in I'm incredibly sensitive and more responsive to its actions in relieving the symptoms of P.D.
Hope this helps.
Lee