Many times, patients tell me they would like DBS to improve their thinking, handwriting, driving, balance and walking. These expectations are realistic when you consider how much these symptoms impact a person's independence. However, knowing what DBS can actually do for you is very important before undergoing brain surgery. As a general rule, stimulation will improve the same symptoms that are improved with levodopa IF the wire is well placed in the brain and the stimulation is appropriately applied. Inappropriate stimulation can even worsen speech, walking and balance. The good news is these problems are reversible with proper adjustments to the stimulation.
What is reasonable to expect from DBS? Stiffness, slowness, shuffling, tremor, off time and dyskinesia should improve but may take weeks to months to see optimal results. Sometimes it can take up to 6 months to fully adjust the stimulation settings. Cognition, speech and gait freezing are symptoms that do not respond to stimulation and can get worse after surgery in some people. Rarely, gait freezing could improve if it improves with levodopa, however, gait freezing should not ever be the primary reason for having DBS as the risks of brain surgery are not small.