If MRI or any other radiology can give this kind of information, it can help calculating the amount of CSF needed to be drained before shunt insertion. This is very important
Trough iperintensity around the cerebral ventricles in T2-FLAIR sequence, you can get an indirectly amount of transependymal diapedesis. it's not possible to calculate directly the shunt or the flow rate of CSF in the ventricles, but measuring the stroke volume (calculated as the mean of systolic outflow and diastolic inflow) in aqueduct of Sylvius, you can have a way to estimate the amount of CSF to be drained.
Thanks too much Dr Vincenzo for your answer. I think this is very important. Do you neurosurgeons who are using this knowledge? Do you see the whitish areas disappearing after shunt?
In our radiology center we perform these kind of analysis (Stroke volume, CSF dynamic and advanced neuro-MRI scan).
Generally the iperintensity areas, with a good regulation of shunt, tend to reduce. After the surgical treatment, the study of the liquor dynamics proposed as a follow-up allows, by comparison with the pre-operative Stroke Volume values, to adjust the implanted system in order to optimize the results obtained and reduce complications.
Dr Vincenzo,
Thanks again, I am feeling very happy to know about your good work in shunted patients.
How much is the load of shunts in your hospital, and as such no incidents of overdrainage happened. Is your protocol is a standard reliable guideline in most centres worldwide now or is it your centre protocol? I think it is new? My experience with regular CSF flowmetry was that it is insensitive.
What about fine tuning stage? Do you think your CSF dynamic studies are sensitive enough to help in this stage?
My best regards,
Dr Vincenzo,
Let me clarify a point in my above comment, as your answer here is very very important. My previous experience with CSF flowmetry was that it gave normal when shunt was obstructed! So kindly compare the old method of CSF dynamic studies with the recent one. Kindly explain reasons of the fallacies and independability of old methods. If it is a new technique or a new machine clarify it and kindly mention the names of these new techniques and machines.
I appreciate,
Dr Vincenzo,
I think you have important clues for good regulation of shunt. In your first comment, you said it clear that you cannot judge the shunt itself which is the same of my experience of false results of regular CSF flowmetry. You are a neuroradiologist who is talking about advanced MRI techniques.
My question is:
Can you guide neurosurgeons for good shunt control? Good shunt control means Zero overdrainage + ability to fine tune to optimal. If yes, kindly explain details of this point.
I appreciate,
In our radiology center we provide only diagnostic information, so we don't physically perform shunt regulation as a therapy for pseudotumor cerebri or hydrocephalus.
We have a standardised diagnostic protocol, and we measure CSF flowmetry in the aqueduct of Sylvius, generally in 16 different moments during a single cardiac cycle. These data are converted into volume by multiplying the respective speeds for the acqueduct area. Direct downward flow will be obtained during cardiac systole and upward flow during diastole, in this way we calculate Stroke Volume (SV). The normal SV value is equal to 50 +/- 12 microliters per cardiac cycle.
Of course this method requires high field MRI scanner, ad-hoc sequence for CSF dynamics, and trained and experienced equipe (radiographer and neuroradiologist).
Dr Vincenzo,
In case you can see CSF dynamics so accurately, why canot you advice neurosurgeons to go up or down by how much?
of course in our medical report we advice to adjust or modify if there are any problems related to clinical question, but in the end, the final decision it's up to the specialist or neurosurgeon in hospital or a therapy center.
Dr Vincenzo,
I do not know how to thank you for all your good answers. You have been very generous and very patient with me.
I would try my best to find papers done in your centre. Also I will try to contact one of your neurosurgeon colleagues to find out the outcome of shunted hydrocephalus patients who were followed by advanced MRI. You have given me a very good impression about how Italy is treating hydrocephalus.
My best regards and wishes,
Dear Seifollah,
I have shared with you above discussion with Dr Vincenzo. What is your impression?
It was very important. It shows clearly first that good shunt control is a clear aim. Good shunt control includes 3 things: well drained brain before starting fine tuning, zero overdrainage incidents and then getting the golden aim of shunt which is optimal adjustment and keeping it optimal through time as CSF is dynamic.
Dr Vincenzo gave us knowledge now that these aims are currently achieved very accurately through advanced MRI. We need to study the papers of their centre. Before, adjustment was done blindly and the main follow up of neurosurgeons was through clinical testing, and regular MRI to see improvement and to make sure that shunt is patent. This was very crude and not maxmizing shunt value added to incidents of serious risks of overdrainage.
In case this solves the problem, I think that researching in monitoring facial muscles or sleep would be only confirmatory and would aim to better understanding of IH.
What is your opinion?
Dear Omer
We know most important concern related to this subject is valve adjustment of shunt.
When we have got change in the CSF pressure, at the same time, the adjustment of valve of shunt should be change according to new pressure, however, current smart shunt couldnot do this (I'm not sure). MRI couldnot also measure CSF pressure. My recent paper showed CSF velocity or flowrate which are measured using CINE PC MRI are not proportional with intensity of hydrocephalus and not proportion to condition of shunt. The calculation of CSF pressure using computer simulation is also very time consuming process and only useful for research assessment. Hence, we should find other available parameter for controlling valve of shunt. However, if we find new parameter like "stimulation of facial nerve", controll of valve of shunts according to this new parameter is also our new problem......
Solving of upon two issues are not easy and are very complicated
Dear Omer
We know most important concern related to this subject is valve adjustment of shunt.
When we have got change in the CSF pressure, at the same time, the adjustment of valve of shunt should be change according to new pressure, however, current smart shunt couldnot do this (I'm not sure). MRI couldnot also measure CSF pressure. My recent paper showed CSF velocity or flowrate which are measured using CINE PC MRI are not proportional with intensity of hydrocephalus and not proportion to condition of shunt. The calculation of CSF pressure using computer simulation is also very time consuming process and only useful for research assessment. Hence, we should find other available parameter for controlling valve of shunt. However, if we find new parameter like "stimulation of facial nerve", controll of valve of shunts according to this new parameter is also our new problem......
Solving of upon two issues are not easy and are very complicated
Dear Sefoallah,
Dr Vincenzo is talking about advanced MRI with many views of CSF flow. Regarding monitoring facial muscle behavior with CSF pressure change, you can go forward for its investigation. I will cooperate anyway I can. I hope you will get positive results. MRI technical points you are talking about as well as Dr Vincenzo new technique are beyond my knowledge. It would be very useful to discuss it direct with Dr Vincenzo.
My best regards,
We can ask Dr Vincenzo himself to share us any literature or papers done in his medical centre supporting his answers on your rquest.
I will share him this request as well as your above points and we will wait his reply.
Best regards,
Dr Vincenzo,
Kindly can you share us or guide us to literature giving details of role of advanced MRR in hydrocephalus and the accurate CSF dynamics described above.
My best regards,
Dear Omer and Vincenzo
Below title is my previous paper which showed in all hydrodynamic parameters of CSF (e.x. velocity, flowrate, pressure....), only CSF pessure is sensitive parameter for assessment of hydrocephalus condition.
Current MRI method couldnot measure CSF pressure.
Dr. Vincenzo, do you know any new method for calculating CSF pressure using MRI? I familiar with CINE PC MRI which can measure only CSF velocity and flowrate.
Furthermore, invasive method like ICP monitoring and LP can measure CSF pressure in the special hydrocephalus patients in special conditions.
Title of paper:
FSI simulation of CSF hydrodynamic changes in a large population of non-communicating hydrocephalus patients during treatment process with regard to their clinical symptoms
Dear Seifollah,
I have shared Dr Vincenzo with your above comments, as he is the best one to discuss it with you. Down I will copy/paste his words earlier:
" We have a standardised diagnostic protocol, and we measure CSF flowmetry in the aqueduct of Sylvius, generally in 16 different moments during a single cardiac cycle. These data are converted into volume by multiplying the respective speeds for the acqueduct area. Direct downward flow will be obtained during cardiac systole and upward flow during diastole, in this way we calculate Stroke Volume (SV). The normal SV value is equal to 50 +/- 12 microliters per cardiac cycle.
Of course this method requires high field MRI scanner, ad-hoc sequence for CSF dynamics, and trained and experienced equipe (radiographer and neuroradiologist)."
My best regards,
What does upward and downward mean in the "Direct downward flow will be obtained during cardiac systole and upward flow during diastole"
Dear Seifollah,
I canot answer you in this regard because of lack of radiology knowledge. We have to wait for Dr Vincenzo response.
This does not contradict our project of finding other sensitive indicators. On the other hand it does not mean of course we are putting aside MRI. We have to clarify it and search literature about it. Also to find out papers of results of patients outcome in those regulated by the above MRI technique.
Dear Seifollah,
Your Comment two days back, you wrote "facial nerve stimulation". Our target would be monitoring facial muscle tension in groups.
The points you are raising are important, and I wonder why neurosurgeons and neurologists are not coming in to share us this discussion?
Do they see that we are talking irrelevant?
Let us wait and see.
Dear Omer
What is the scientific parameter for assessment of muscle tension? My skill is Biomedical engineering and in Biomechanics science, we assess this using evaluation the stimulation of these nerves. However, please give me enough time. Because Im discussing my friends (neuroscience physician and neurosurgeon). It wouldn't be an issue if other researcher wouldn't like to help or share with us during this discussion and process. I think that we can start this project if I be sure about the vague points of the project. Please give me time
Do you have any idea about the problem that I mentioned earlier. For example we find the relationship between these nerves and condition of the patient after shunting. How can we connect this finding to "valve adjustment" of shunt?
Dear Seifollah,
I have passed through many adjustments, and it was clear to me that at different adjustments facial muscles tensions change in pattern and degree.
I went gradually down to zero but after a time I suffered my first overdrainage (MRI documented). So I have to return up gradually to be stabilised on 12 for a time. On trying to practice swimming I got my second overdrainage and I had to go further up gradually and now I am 18 and my expected target is 20. So blind adjustment to optimal is difficult and takes a very long time and also have overdrainage risks.
During my repeated adjustment trials I noticed that tension is more on front facial muscles supplied by facial nerve during overdrainage. On the otherhand when CSF tension was most probably high the tension of lateral facial muscles was more. These observations have become a self guide to me. My question is: are the same is happening with other patients? If research shows consistency, facial muscle EEG might help adjustment. If not consistent we have to search for other sensitive indicator like EEG during sleep. We have to concentrate on pseudotumor cerebri first.
Dr Vincenzo gave me above great hope, on discussing imaging and calculation of CSF dynamics. Further discussions with hydrocephalus doctors and neuroradiologists are needed to clarify your diagreements. Regular MRI and clinical testing are not enough in my opinion. Dr Vincenzo is describing advanced MRI. A drowning person hardly will gave up to leave away a rope of hope.
My best regards,
Dear Seifollah,
Importance of answer of Dr Vincenzo is that calculation of the amount needed to be drained before shunt is very important. The value is not only for confirming diagnosis in the 3 days drainage test, but also it empties brain from accumulated CSF over many years. If this is not achieved before shunt implantation, adjustment should be at first low to drain this amount. When collected CSF is drained then we can come up for real adjustment until achieving optimal. This adjustment is the correct one which should stay with the patient for a long time. Many will put it after drainage at 20 which is very reasonable. Then go little up or little down to come to optimal. The expertise of shunt control is to achieve the balance between CSF secretion and CSF drainage. But this should be done after squeezing the collected CSF out of the brain. If not, adjustment to optimal would be very confusing and the neurosurgeon has to compromise and accept some adjustment which is not correct as we did not come to CSF balance. Small number of neurosurgeons are doing shunt control correctly as explained above. If not done we are then failing to cure a reversible condition. Recovery is 70-80%.
Suppose a patient, like what happened with me, passed a drainage test and first shunt was implanted. Then shunt was obstructed and a second shunt is needed after few years. What is usually done is to implant the shunt without drainage as 3 days drainage is regarded as a diagnostic test and diagnosis is known. Some also will drain 50 - 100 ml for diagnosis. In my opinion these practices are incorrect.
Dear Seifollah,
Do you recognize now the importance of Dr Vincenzo answer? Suppose also that Dr Vincenzo guides also in fine tuning, it will lead to very good shunt control.
I hope also that others would not underestimate our search for other sensitive indicators like EMG of facial muscle groups or EEG during sleep or others which I donot know.
My best regards,
This old paper is interesting
Furthermore, my idea is this: during change in CSF pressure, at the same time, the adjustment of valve must change proportional to changes in pressure amount. I think this the meaning of smart shunt. Your idea is this: we have unbalancing in the CSF production and drainage, ok, how can we solve this problem? The meaning of smart shunt is this that it controls this unbalancing and donor let to creat exceed CSF
The title of old paper is this
Reversible facial pain due to hydrocephalus with trigeminal somatosensory evoked response changes. Case report
Regular shunt can do it. The confusion comes from 2 things as I explained above:
1 Correct drainage before shunt implantation.
2 To monitor fine tuning by a sensitive indicator like what mentioned or advanced MRI in case you got more information.
Omer
What is the exact definition of Pseudotumor Cerebri? I think these patients have problem about the drainage place of CSF in the sugital sinus. For example, there is the infection in the sugital sinus. Is it correct?
Before I have to clarify that I meant by regular shunt a programmable one versus the smart shunt.
What you mentioned about pseudotumor cerebri is correct. It is called also idiopathic intracranial hypertension (IIH). If the reason is known like venous stenosis or deficiency or others it would be called intracranial hypertension (IH):
https://youtu.be/Ml-TZIiBkwk
Important also to stress to be very cautious on adjusting valve low because of risk of overdrainage. Neurosurgeons who are doing it after MRI calculation are more confident in doing it without the risk of overdrainage.
Seifollah,
The paper you referred to about effects of hydrocephalus on facial nerve and trigeminal nerve confirms my experiences during adjustments. Can you send it to me?
Regarding your comment about smart shunt, I can guess that smart shunt is a machine that can be set to a certain range of pressure or flow or someother parameter. Where is then the patient? Smart shunt should have an input from things like valid advanced MRI calculations, or some other sensitive indicator like what we are looking for. If this sensitive indicator is known in some centres, why it is not well known in most centres all over the world? This is against medical ethics. I ca not say that it is ignorance as there are many many well qualified neurosurgeons. There are huge number of hyxrocephalic patients who should benefit from this piece of neurosurgical knowledge.
Why am I saying that?
Why
Some medical centres and neurosurgeons are getting better results than others. Possibly I am wrong, and the good results have become present in many centres all over the world. Then if this is the case, we as developing countries, have to improve ourselves and take steps against our ignorance of new developments.
I have a feeling (not scientific) that Dr Vincenzo gave us important clues, but I can not answer your technical questions. I feel also grateful to him as he answered my question. So I think that you should not disregard his answers.
All the above is of course is not against to our intention research project about facial and trigeminal nerves.
My best regards,
Omer
I told you that my definition of smart shunt is this and current smart shunt couldnot satisfy me and couldn't do this important duty (self-adjustment)
There is no this smart shunt and we would like to achieve the this. Omer you are right and in my previous comment I noticed you that our main problem will be finding of indicator. I think (I am not sure) the results of MRI or computer simulation methods couldn't be helpful for us because we cannot connect those results to the adjustment of valve. However, I am assessing this subject.
Omer can you search about new progress in current smart shunt?Mybe this be helpful
Thanks Seifollah. Currentl I am trying to pass a first part exam. of a diploma in General Medicine. After 1 month In Shaa Allah I would have more time to know about smart shunt. But the technical part would be difficult for me and so I have to ask you some questions.
Seifollah,
Self adjustment is not advised at all by patient in any shunt and at anytime. The patient can describe his symptoms and can discuss with his doctor. The doctor should be a good listener and giving time to the patient. Also doctors should be given sensitive indicators because regular clinical testing and imaging are not enough. Suppose a patient is sitting for a spectcle testing and he is misguiding his optician intentionally or unintentionally: Can you expect a result of a good spectacles and vision!
Your approach is interesting for me.
Dou sure about "Self adjustment is not advised at all by patient in any shunt and at anytime" ?
I think CSF pressure is main and sensitive indicator for assessing the condition of hydrocephalus (unless NPH). and other indicators are the result of pressure changing.
If physician know the correct value of pressure, he can diagnose the condition of patients without regard to their clinical evidence. I know It is great claim, however, ideally this is my opinion. Hence, self adjustment of valve of shunt will be sufficient and good
The reason why it should be under medical supervision is that overdrainage can result in hygromas and subdural hematomas which are very serious and potentially killing. If happened the valve should be closed for 3 months until MRI shows clearance. After that valve is readjusted to a chosen higher level.
That is the reason why sensitive non invasive indicators are needed. Neurosurgeons clearly recognise this situation, and so they are more on the side of a compromise at a higher value. These higher values are not the good answer in many clinical situations. Also it shortens shunt life because of partial stagnation. So I think you cannot start your project without cooperation with good neurosurgeons and neurologists. It should be a team which would include also neurophysiologists and neuroradiologists.
Do you have this team in your hospital who are accepting to cooperate?
Finally let me ask you:
What are the challenges to get a successful shunt?
I am now in the mood of medical examinations.
Try first to enumerate these challenges and I would follow you.
My best regards,
I forgot to mention above that I am sympathetic with neurosurgeons for their overcautious decisions in the context of unclear guidelines nor semi-accurate indicators. This reflects in my opinion the need of our or similar researches. Otherwise neurosurgeons in good centres who are achieving good results sbould discuss it openly with us and declare their protocls. Their professional secrets will decrease the morbidity and mortality for millions of patients worldwide. If you want to talk more of this drama you need to think of the many poor countries. Where is WHO?
My best regards,
This subject become complicated. I do not access to complete team. Because in my country, almost neurosurgereon think about money not research for developing their knowledge....
By the way, Omer, where do you live? Are you student or.... ? Do you collabrate with University or Hospital? How old are you? How long do you suffer hydrocephalus?
I was born with beginnings of pseudotumor cerebri and I was diagnosed when my age was 56. Confirmation of diagnosis was on 2007 in Germany when my age was 57! I knew the reason of my IH about 3 years back when MRV ordered by myself. I suspect many patients in my family as it is a genetic disease. Up to moment I have confirmed 3.
I am living in Cairo/Egypt. My age now is 67. I tried to contact several institutions to give me a chance for more studies and research on CSF but in vain. I went to experts in a conference in Singapore and presented my case on 2013 which was published. It costs me from my own pocket not less than $ 2000. This doesnot get seen interest by me. I tried WHO office in Cairo, but they refused to meet me as they are not dealing with individuals. Also universities and research institutions here were frustrating. So now I am trying to finish a diploma in General Medicine. This will take not less than 1.5 yeard.
So I am giving my opinions, questions and comments on air (Researchgate) as it might help any interested research.
Also the discussions can increase general awareness of the problem.
I think the problem I faced is: How a patient with a brain disease can help in research. My motives are not self-centered.
Dear Seifollah,
Challenges of a good shunt which I knew over the last 10 years include:
1 Correct decision to implant a shunt
2 Measures to avoid infection during implantation. Some centres achieved zero infection
3 Choice between available valves
4 Choosing shunt site: e.g.,VP or LP
5 Placing of tip of ventricular catheter in a good place like at Monro,s foramen
6 Length of abdominal catheter
7 Valve adjustment
8 During follow up to exclude any maladjustment or shunt obstruction
9 Diagnosing any complcation early
The above are to my knowledge. Some neurosurgeons advise their patients to avoid implanting a shunt. I disagree. Those working on improving shunts and hydrocephalus undestanding include; neurosurgeons, neurologists, neuroradiologists, bioengineers, pathologists, vertinary reseachers, physicits, mathematicians, shunt manufactures and may be others. All my respect and my gratitude to all of them. They are trying to help me and others.
Best regards,
Seifollah,
I am not trying to get a special previlage for hydrocephalus or me. Surely you understand that. All kinds of illnesses should have equal attention:
https://youtu.be/8LZJz7GtJA0
I was only trying to tell my experience. Also to confirm the known attention that hydrocephalus is a reversible condition with a very good chance of full recovery. Also it happens in a very young age. There are also problems in early diagnosis.
For LP, most neurosurgeons prefer VP shunt as it is more safer. Risks of the dangerous overdrainage in LP are much more according to majority. I was lucky to pass safely twice the overdrainage. I think having 2 valves (proGAV+proSA) was part of my passing safely the two incidents. I think that they offered resistance and slowed CSF flow. It could also be the VP shunt and not LP shunt had a role in safety.
A shunt was the plan of my neurosurgeon and not the ETV. I can not say anything more about the comparison.
Note that I am now near optimal after 6 years. I am not a candidate for shunt change except if obstructed or anyvalve malfunction. Also currently I am not a candidate for ETV.
My discussions with you and other experts target is to clarify things and to help others from my long selfexperience. I am sorry to interfere out of my domain. Four shunt operations and 6 years for adjustments are too much. Also surely we are talking about a curable disease which is happening at young age and seriously is affecting brains and lives of hydrocephalic patients. With my notes or without them hydrocephalus diagnosis and treatment has been advancing. There are researchers who are working on it day and night. I am only trying to offer my share.
My best regards,
Seifollah,
Can you talk about yourself? How do you become interested in CSF? Why is it attracting you more than other points? Can you describe your hospital or research centre?
My MSC and PhD thesis were related Hydrocephalus. I accedently faced with this subject
It was an accidental confrontation but you look very interested in CSF. You shouldnot withdraw. We have to face difficulties; it is a challenge.
Dear Seifollah,
I think we shouldont frustrate or withdraw if neurosurgeons are busy with other works. I can mention to you 3 reasons:
1) We are focusing on a point which is a key factor in success in shunt treatment which is to search for "a very sensitive indicator which aims to come to an optimal balance in pseudotumor cerebri" and may be also to other hydrocephalus. Our target is not a compromise, a judgment, nor luck in achieving adjustment. Outcome in hydrocephalus depends on this accurate adjustment, and so all other researches on shunt challenges which I mentioned to you before, will not work without an adjustment indicator and protocol. If this protocol is already present, all we need is to know it and spread it to all neurosurgical centres to be implemented. Sincere researchers will not only work for credit but for scientific truth and for patients.
2) You have with you a unique human experiment, that chances never allowed a second one in any patient. This is me with 6 years of many adjustments to optimal and 2 incidents of radiollogically documented overdrainage. I think that these are experimental data which should not be disregarded.
3) You as a CSF Ph D is elligible to write to hydrocephalus associations, universities and hydrocephalus research centres.
4) We should also try to collaborate with other reseachers.
My best regards,