Normal Pressure Hydrocephalus

I'm currently seeing a 60 y/o gentleman with normal pressure hydrocephalus (NPH) on an outpatient basis.
He has been diagnosed for about 3 years now and was recently admitted after his shunt malfunctioned and he had a revision done. The revision helped significantly and now he's home. I've been seeing him for about a month and I'm realizing that we are plateauing. I started researching the literature for some guidelines on PT approach in this population and there is very little. Most of the articles refer to acute care management, gait characteristics of NPH vs. Parkinson's disease, and NPH pre/post lumbar drain testing prior to shunt placement. Nothing I can find really makes recommendations for chronic management.

As for the specifics of his case, he demos fairly common gait characteristics: small step length (festinating when fatigued) that worsens in doorways and turns and in dynamic situations. Also reduced arm swing unilaterally with ipsilateral pelvic protraction. He is easily distractible, and like many of my PD patients, cannot multitask very well. His carry over early on was good, most notably he was able to stop himself at the first sign of festination and begin his gait cycle again with focus on a good first step. This has cut down significantly his furniture walking and wall grabbing tendencies. Now, he always begins stepping well, including a fair amount of left arm swing. But soon, he is taking short steps on the left again, the trunk gets rotated anteriorly on the left, and he has to stop and start over after about 75'...and that is when walking in a straight line on level surface! Strength is near normal and tone is normal. There is mild neuropathic sensory loss in the feet due to diabetes. Endurance seems limited and has definitely been a target area. I've encouraged use of the recumbent bike at home because his fear of falling and tendency for increased instability with fatigue limit his ability to push himself with walking distance for the purpose of increasing the stamina. So my main goals are to improve his stability in a wider variety of environments, improve functional endurance, and to improve his specific ability to self-manage his home environment which is small and has lots of turns. Mostly, I've used strategies that have been successful with moderately impaired PD patients but we are hitting a wall and from what I understand from the research I have found, the two diseases appear similar, but probably impair motor planning in different ways. Therefore, some say verbal cueing doesn't work well in this group (like it does work fairly well in PD). We tried using a metronome in a couple of sessions but I'm not formally trained with it. Pretty mixed results.

So again, 2 part question: 1) What evidence based (or expert opinion based) guidelines exist for chronic management of NPH? Any articles even that address this issue? 2) What do you think about this particular patient as I've described him?

Thanks in advance for your feedback.

Jerram