The brain is the most sensitive organ in human body and consumes the maximum amount of oxygen and other nutrients to keep it alive and healthy. Thus, the brain needs to be continuously fed with fresh oxygenated blood, whilst deoxygenated blood is flushed out.
Any disturbance to the supply of oxygen or nutrients can irreversibly damage the brain, resulting in serious to fatal implications. There are many cases where this can fail… for instance, due to a heart attack, due to brain tumors, due to blood clots caused by hemorrhage etc.
The ability to study the rate of flushing of brain with blood (called Neuro Perfusion) can be of great help for clinicians to correctly diagnose, detect and devise treatment plans for patients.
Researchers at the Philips Innovation Campus in Bangalore have recently come up with an innovative software package called ‘Neuro Perfusion Package’ (NPP) to help doctors correctly detect brain abnormalities by analysing metabolic characteristics of brain tissue.
S Bhaskaran, Senior Director, Philips Innovation Campus, Bangalore talks with eHEALTH about this innovative solution and its potential clinical applications.
Q. What is Neuro Perfusion?
The brain – like any other part of the human body – requires a constant supply of blood. This is achieved through a complex system of arteries and veins that spread throughout the cranial encasing to ensure that every part of the brain receives the blood supply it needs. The blood in turn supplies all the nutrients required by the brain to keep it alive and healthy. Not surprisingly the brain uses the maximum amount of nutrients per gram vis-à-vis any other part of the body. This is called Brain Perfusion or Neuro Perfusion.
Q. What are the techniques for measuring Neuro Perfusion?
There are of course various quantitative techniques for determining the exact quantum of neuro perfusion. Neuro perfusion can be studied using Magnetic Resonance, Computed Tomography or Nuclear Medicine modalities. Let us take the example of the MR modality. A contrast agent (eg. Gadolinium) is injected into the human body. The initial uptake of the contrast agent by blood vessels in the brain, till it is completely flushed out of the brain is of interest in this study. This gives us a number called the ‘Cerebral Blood Volume’ (CBV). A specific slice of the brain is examined using the MR scanner – starting from the moment the contrast agent starts entering this slice of interest, till it is completely flushed out again.
All of this is done automatically by the clinical software package – NPP or Neuro Perfusion Package.
The CBV in various regions of the brain are compared. The clinician can then determine if any specific region of the brain has more CBV or less CBV than the normal condition. If such an abnormality exists, the clinician can determine the cause and recommend corrective steps.
Q. What clinical inferences can be drawn on the basis of neuro perfusion study and under what conditions it needs to be monitored and/or controlled?
There are of course many possible infections and injuries that a brain can be subjected to. And of course not all cases can be detected by a Neuro Perfusion Package (NPP). What can however be detected are those events that impact the quantum of blood being supplied to a specific part of the brain. Let us discuss two such examples.
The first example is that of a blood clot. A blood clot can develop within the brain or a clot can travel from other parts of the body and embed itself in the arteries supplying blood to the brain. This can lead to one of two situations. Either the part of the brain supplied by the blood vessel is starved of blood and dies. Or the blood vessel bursts because it is incapable of withstanding the pressure of the blood building up behind the clot. This causes a flooding of that part of the brain with blood. This typically leads to all the symptoms of a stroke. In both situations, the CBV value changes and can be detected by a Neuro Perfusion Package. The clinician again can determine the exact course of action based on the quantitative data provided by the package.
The second is the case of a tumor inside the skull. The tumor needs additional blood to continue to live and grow. This is achieved by a process called angiogenesis which promotes the growth of additional blood vessels that supply the tumor with the required nutrients. Obviously the part of the brain which houses the tumor will have an above normal CBV. The clinician can then quickly do a more detailed examination of this part of the brain to decide on the best course of action.
Q. How does the Neuro Perfusion Package (NPP) developed at Philips Innovation Campus promise to improve clinical outcomes?
The ultimate goal of any clinical application package is to:
- Provide accurate information to the clinician – reduce false positives and negatives. The pathology, if it exists, must be recognised by the application and no extraneous artifacts must be recognised as pathology.
- The protocol must be reproducible – there are two aspects to any clinical application package, the actual protocol of the image acquisition itself (that is the imaging of the patient) and the translation of the raw data to clinically meaningful information. If neither of these steps is reproducible, the protocol will have little impact on clinical outcomes.
- It must be simple for the clinician to use – independent of how complex the application/protocol itself, the clinician must never lose focus of the patient.
The NPP satisfies all these conditions. It is accurate, repeatable and extremely simple to use. The radiologist needs very little additional training to be able to use the package.
Q. For how long did your research in this application go on before you came up with the application? Besides PIC-Bangalore, did any part of the R&D happen elsewhere as well?
It is difficult to determine the exact amount of time required to come out with any new clinical package. Typically the concepts come from our research labs or from luminary clinical research sites. These are then converted to pre-clinical packages before clinical trials can start. It is only after this phase can an engineered package be delivered to the open market. Thus many companies, research institutes, clinical labs, doctors and engineers are involved before it hits the market. Only the most simplistic of clinical packages can be the outcome of any one company’s endeavor. PIC Bangalore was involved in engineering the current version of the product as is sold in the market.
Q. Is NPP already available in the market? What are the target clinical specialties where it can have potential use?
Yes, it is available in the market. The target is typically the study of Oncology related events in the brain. Conditions such as angiogenesis around a tumor can be easily determined through this technique. The other situation would be in cases of blood clots leading to a starvation of a part of the brain.
Q. What other cutting-edge research are undergoing at your campus?
We have quite a few research programs underway at any point in time. And across all modalities. Some of the other packages that we have already released for commercial purpose from out of our lab include:
- MR Packages: Functional MRI.
- CT Packages: Bone Mineral Density Analysis Package.
- NM Packages : Multigated Acquisition for Cardiac Applications.