 I am a consultant neurosurgeon and head of the department at Madipa hospitals Baner Pune and my specialization is in cerebrovascular surgery and epilepsy surgery. So friends today we are going to talk about brain bypass procedures and in what conditions it is done. So it is an interesting topic because we are connecting one vessel to another vessel inside the brain. So that is a bypass procedure. So it is typically carried out whenever there is ischemia or less blood supply to the brain in particular conditions like from those aneurysms or giant aneurysms or a particular disease called as Moa Moa disease. So whenever there is less blood supply to the brain and the patient is suffering from recurrent strokes or episodes of ischemia then we consider a bypass procedure inside the brain. So it can be either a low flow bypass or a high flow bypass. So typically we will talk today about Moa Moa disease, Moa Moa means a puff of smoke in Japanese language and majority of the patients were initially found in Japan. So it is a particular condition in which there is progressive narrowing of the internal carotid arteries which are the main vessels which supply the brain. So it is an idiopathic process we do not know why exactly this happens and the narrowing occurs from inside the lumen of the vessel. So this disease can occur in children as well as young adults, the symptoms can be ischemic that is because of stroke, they can have recurrent weakness, upper limb, lower limb or facial asymmetry or they can have sometimes hemorrhages also inside the brain. So what happens exactly is because of this progressive narrowing the blood supply to the brain becomes less and less and the brain becomes thirsty and it keeps on drawing blood from the external carotid circulation which is outside the brain. And so what happens is there is lot of collateralization or extra vessels which come inside the skull base or the base of the brain to increase the blood supply to the brain. That is why this appearance of these collateral looks like a puff of smoke on angiopathy. So whenever someone has these strokes, recurrent strokes or ischemic symptoms we subject them to MRI and VC, infarcts or areas of less blood supply and the diagnostic test for this molybdenum disease is a BSA that is a digital subtraction angiography that is an angiography of the brain and it typically reveals there is narrowing of the internal carotid arteries near the base of the brain. So how do we treat it? So basically there are no medications which can reverse this narrowing. So we have to give anti-platelets like aspirin to these patients to prevent the future episodes of stroke. However, a definitive treatment for this disorder is a brain bypass. So the bypass can be indirect bypass as well as a direct bypass. So what we are specialized in is a direct bypass. So direct bypass is always combined with an indirect bypass. So whenever we do a direct bypass of one blood vessel to the blood vessel inside the brain there is an indirect re-vascularization which is also taking place at the same time. So what do we do in brain bypass procedure? This is typically a bypass between superficial temporal artery which is a blood vessel of the cheek which supplies our scalp to the middle cerebral artery that is the MCA which is a small blood vessel inside the brain. So this is typically called as SCA MCA bypass. So typically we harvest the blood vessel from in front of the ear and take it inside the skull by doing a small craniotomy and we anastomose the blood vessel with fine sutures by approximately 10 to 12 knots and we connect one blood vessel to the other blood vessel and the blood supply typically increases over a period of time and in future these patients do not suffer or suffer less from the future SCA MCA attacks. So after doing this bypass procedure the blood supply to the affected brain increases slowly over next 2 to 3 months and the ischemic symptoms of the patients reduce in severity as well as frequency and these patients however remain on anti platelets for lifelong. So to conclude brain bypass procedures are complex neurosurgical operative procedure in which one blood vessel is anastomosed to another blood vessel inside the brain to increase the blood supply of the brain and this procedure is carried out in very few centers in India and Manipal Hospital Barnair is one of them. So just to demonstrate I will show a small video of the same procedure that is the SCA MCA bypass and we can see this is the brain and we will be opening the CVN fissure and this is the superficial temporal artery which is seen here which is the donor vessel we have harvested from in front of the ear we are actually anastomosing now this blood vessel to the middle cerebral artery so these are the fine sutures being taken and once the sutures are completed you will release these clips and allow the blood to flow. So this is how this procedure is done and these patients do well after surgery and they can lead a normal life which is free from strokes. So this procedure of direct re-visualization is carried out at very few centers in India and Manipal Hospital Barnair Pune is one of them.