Hi,

With good clincal result I will avoid invasive testing. We are monitoring patient clinically and with neuropsychological tests. If something is going wrong brain imaging is done. At the end invasive testing.

Thank you too much.

This plan looks very sensible to me Dr. Mariusz.

Can you kindly refer me the details of those clinical points as well as the neuropsychological tests which guide you before doing further investigations.

If improvement happened after a lower adjustment: how do you know if this improvement is a part of a long adjustment procedure or due to shunt obstruction which has started? 

I just don't understand your question completely. A clinical improvement due to shunt obstruction? That should not exist, unless the patient does not need a shunt at all.

NPH: in case of recurring symptoms we perform a test battery to objectivate the symptoms, neuropsychological testing and video analysis of gait and balance, followed by a lumbar infusion test (Liqvor Celda system) to discriminate between shunt malfunction and progressive disease with adequate shunt function, in the latter case we would lower the pressure setting of the valve. otherwise only shunt revision.

IIH: in case of recurrent papiledema we would revise the shunt after an LP, in case of only headache we would perform an LP or preferably another lumbar infusion study because in that case we can perform a shunt performance study.

Brain imaging is of no help in NPH or IIH, although we still perform it.

Hello Erik,

Thank you too much for your sharing answer.

I will try to clarify down:

First we have to agree about one point:

Are you a supporter of fine adjusting patients to optimal or the most possible near to optimal or not? To do this safely you have to go down slowly. 

As discussed before with Professor Satoko Ochi in a previous question of me he said:

"Depending on the pre-shunt examination,such as tap test, CT,or MRI, you will estimate how much volume of CSF is needed to drain"

I liked Prof Satoko words above too much.

If this drainage calculation is not well done, adjustment procedure might take a very long time up to 2 years (you are going down slowly for safety consideration). By this time possibility of partial obstruction is there.

How would you be able to differentiate between partial obstruction or a further need to go down for adjustment? If it is obstruction the patient will need invasive investigations.

Am I clear now?

Nobody knows how much drainage in terms of volumina is required or needed, it cannot be estimated or calculated. And you cannot regulate the drainage accurately, only change pressure settings. Their are to many factors that you cannot influence or take into the calcuation. Therefore I do not believe at all in adjusting and finetuning, maybe with a few exceptions. Programmable valves create a new disease and additional morbidity of dependency on doctors, hospital, scans and reprogramming valves. The optimal valve is a gravity-assisted valve with a fixed setting. Odcourse no evidence at all, but this is my opinion and experience, after having used and tried quite a few different types.

best regards, Erik

Thank you Dr Eric for your clear and straightforward answer. Can you kindly refer me to the papers supporting your opinion.

Best regards,

Omer

1) I am inviting Dr Marc Eric and Dr Sokato Ochi and other experts to share us in this discussion with Dr Erik to enrich it. I am expecting clues to come out regarding the confusion between using either programmable valves or fixed pressure valves. Also discussion is needed regarding the amount of CSF needed to be drained through the 3 days drainage test. I call the latter a curing stage. And I am calling the shunt as the maintaining stage.

2)Respected Dr Erik; I agree totally with you that odcourse  is a very weak evidence, but ignoring odcourse is a mistake. Some discoveries in Medicine were related to chances which were followed up.

3) Dr Erik words: Programmable valves create a new disease and additional morbidity of dependency on doctors, hospital, scans and reprogramming valves.

The above opinion shows clearly current situation of disagreement between neurosurgeons in this point. The words of Dr Erik clarifies clearly that this good technology needs a sensitive indicator to make neurosurgeons see what is going on at different CSF levels.This is a must to make programmable valves work optimal.This makes me believe strongly that my trial to raise this issue is very relevant. I hope my endeavors added to ongoing research would not be a waste. My main reason of sharing is to help with my odd experience in this point. Hydrocephalus is a curable disease and hydrocephalic patients should not have this long suffering. We have a lot of excellent neurosurgeons as well as very good technologies. What else is missing?

My Respect and Regards,

Omer

Dear Omer:

I share the view that gravity-assisted valves with so-called shunt assistant should be used whereever possible to avoid overdrainage, that adjustable valves carry risks in terms of mismanagement and iatrogenic complications and that the potential of "fine tuning" may be overestimated. Furthermore, the parameter of interest is intracranial pressure and not CSF volume needed to drain (which due to temporal variability cannot be sufficiently estimated). Adjustable valves may have a role under special circumstances, e.g., when the brain compliance unexpectedly changes with time, but I do not support the concept of using adjustable valves to titrate the lowest possible pressure setting without creating overdrainage. By doing that, how can we know that we don't just compensatorily amplify CSF production to keep the right balance that could already have been reached at higher valve settings? We have to keep in mind that hydrocephalus is a highly dynamic, not a static process. Thus, determination of "the right valve setting" (I would rather speak of a suitable pressure range) finally depends on the optimal alleviation of clinical symptoms.

Kind regards,

Marc

 Dr. Marc,

I am appreciating too much for your response.

"The right valve setting" finally depends on the optimal alleviation of clinical symptoms.

Can you kindly clarify: in case of fixed gravity assisted valves, how do you come to the right setting. How much is the possibility that patient is still uncomfortable after operation. I am sure that you have your parameters in choosing the correct fixed valve. But does it happen several times that patient needs a second operation because of incorrect choice? When do you decide to implant adjustable valve?

Furthermore, the parameter of interest is intracranial pressure and not CSF volume needed to drain (which due to temporal variability cannot be sufficiently estimated)

Did you mean that amount of CSF drained before operation is not important? What about Dr. Sakoto opinion in the previous question? I have no intention to raise conflicts, but to understand. Why the 3 days drainage by itself is curing for a period of time?

By doing that, how can we know that we don't just compensatorily amplify CSF production to keep the right balance that could already have been reached at higher valve settings? We have to keep in mind that hydrocephalus is a highly dynamic, not a static process.

Thank you too much for this clarifying sentence. It is very important clarification.

What is your hope for hydrocephalus treatment then?

I appreciate your answer and Dr.Erik answer.

Omer 

I want here to express my thanks to three of our brave neurosurgeons Dr. Mariusz Dr. Erik and Dr. Marc- Eric for their excellent answers of this question which is related to improving outcome.