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- The 4" step. Medicine make surgery redundant. Remember surgery for peptic ulcer, the commonest major surgery as I became a resident and junior consultant. So also stereotaxy. Two ideas now surfaced. First was the recognition that the nigrostriatal pathway was important for Parkinson’s disease and that dopamine was the neurotransmitter of this pathway. The second was cotzias method of getting dopamine into the brain by use of L.dopa rather than published “Reversal of the pathophysiology of Parkinson’s disease” and Stereotaxic frames were mostly dumped. There was no need for stereotaxy, or if no need at all, certainly the need decreased for the rare case, so, as Dr.Bhagwati told me he was doing one case in 3–4 months and no other neurosurgeons were interested in learning the methodology.
- Then advance occurred with the wheel turning full circle. We realized that after 5–10 years of treatment with L.dopa, lots of problems arose and we could hardly help the resistant cases anymore. With that came additional knowledge. We realized that palidotomy of Globus Pallidus Interna (GPi) not only helped a tremor but in fact helped bradykinesia, and hypertonia and freezing too and surgery returned first in Europe and US and now in the last few years in India. We saw, how, as soon as the electrode enters the GPi of thalamus, tremor disappears. Dr. Ho showed us a video of a case he had done and the dramatic change in the tremor and the hand was most impressive. But I was sitting near Dr. Ramamurthy and Dr. Bhagwati and they looked at one another and smiled. Reminds us of 35 years ago they felt. We had seen this and been impressed with the self same finding 30–40 years ago when we were young like the dozens watching today.
- But technology marches on. Medicine does not move in a circle. It’s more like a spiral so through we are coming backwards to what our forefathers were doing or thinking, we are doing it better. The lesion is more exact, the Pallidotomy replaces the thalamic lesion. We can bilateral cases putting the lesion on the more affected side.
- Then a new idea surfaces – Deep brain stimulation. A needle is put in the pallidum GPi and it is attached to a stimulator. We can stimulate the area at high speed stimulus and thereby cause a loss of function. What is the advantage of deep brain stimulation?
- We can increase or decrease the current so if the effect reduces, we can adjust the stimulating parametres to get effects again.
- The affect is not permanent. The needle can be removed, put in another area by the side to give us flexibility.
- We can keep the stimulus off when the effect is not required (sleep) and on when required.
- While pallidotomy is still a little troublesome if done bilaterally, one can do pallidotomy on one side and deep brain stimulus on the other or deep brain stimulation on both sides. And then a new idea. One can put the deep brain stimulation in the substantia nigra and get results even better than GPi lesions. During the conference, Dr.Ho put electrodes for deep brain stimulation in bilateral substantia nigra in a patient at RHC with excellence results. For non–neurologists which cases of Parkinson’s are suitable for stereotaxy today?
