I think it is possible that the patient is developing symptomatic adult hydrocephalus.  At this point, her symptoms are fairly mild.  I explained to them the two methods of testing with CSF drainage.  It is possible that a large volume lumbar puncture would reveal whether she is likely to respond to shunt and I described that test.  About 30% of my patients with walking impairment in a setting of possible adult hydrocephalus can be diagnosed with a large volume lumbar puncture.  Alternatively, I could bring her into the hospital for four days of CSF drainage to determine whether she is likely to respond to shunt surgery.  This procedure carries a 2% to 3% risk of meningitis.  I also explained that it would be reasonable to start with an outpatient lumbar puncture and if that is not sufficient we could proceed with admission for the spinal catheter protocol.