(middle cerebral artery or MCA). This procedure is also commonly referred to as an EC-IC (External Carotid-Internal Carotid) bypass. All of these operations have in common the concept of a blood and oxygen "starved" brain reaching out to grasp and develop new and more efficient means of bringing blood to the brain and bypassing the areas of blockage. The modified direct anastomosis and encephalo-myo-arterio-synangiosis play a role in this improvement by increasing cerebral blood flow (CBF) after the operation. A significant correlation is found between the postoperative effect and the stages of preoperative angiograms. It is crucial for surgery that the anesthesiologist have experience in managing children being treated for moyamoya, as the type of anesthesia they require is very different from the standard anesthetic children get for almost any other type of neurosurgical procedure. Prognosis The natural history of this disorder is not well known. The long term outlook for patients with treated moyamoya seems to be good when direct bypass is used. Although symptoms may seem to improve almost immediately after the in-direct EDAS, EMS, and multiple burr holes surgeries, it will take probably 6 to 12 months before new vessels can develop to give a sufficient blood supply. With the direct STA-MCA surgery, increased blood supply is immediate. Once a major stroke or bleeding takes place, even with treatment, the patient may be left with permanent loss of function so it is very important to treat this condition promptly. Research Recent investigations have established that both moyamoya disease and arteriovenous fistulas (AVFs) of the lining of the brain, the dura, are associated with dural angiogenesis. These factors may represent a mechanism for ischemia contributing to the formation of dural AVFs. At least one case of simultaneous unilateral moyamoya syndrome and ipsilateral dural arteriovenous fistula has been reported at the Barrow Neurological Institute. In this case a 44-year-old man presented with headache, tinnitus, and an intraventricular hemorrhage, as seen on computed tomographic scans. Cerebral angiography showed a right moyamoya pattern and an ipsilateral dural AVF fed by branches of the external carotid artery and draining into the transverse sinus. This extremely rare coincidental presentation may have deeper pathogenic implications. The research into the pathogenesis of moyamoya disease has found a breakthrough with the proposal of a "Mechano-biological theory" of pathogenesis of this disease. A research group in southern India have proposed this unifying theory based on computational fluid