Novel method of calculation of MRI perfusion and comparison of single versus double barrel STA-MCA bypass for revascularisation in Moya Moya disease

Moyamoya disease (MMD) is characterised by supraclinoid internal carotid artery (ICA) narrowing causing cerebral parenchyma to starve. Direct and indirect revascularisation techniques are the treatment norm. We provide a clinicoradiological comparison of single and double barrel superficial temporal artery to middle cerebral artery (STA-MCA) bypass for MMD. The perfusion in cerebral hemispheres and vessel density in DSA have been evaluated using novel algorithms. DSA, ASL MR imaging methods and Suzuki, Matsushima, Angiographic Outcome Score (AOS) scales were used to quantify perfusion parameters; modified Rankin score (mRS) was used for clinical evaluation. A novel image processing algorithm was designed to perform analysis of ASL sequences and compare perfusion. Vessel density was calculated using connected component analysis on thresholded DSA images. 54 hemispheres with MMD underwent STA-MCA bypass 42(77.8%) single barrel and 12 (22.2%) double barrel. Clinical outcome - mRS was significant with p