DNAH8 and Parkinson disease: To further evaluate the impaired energy metabolism in the occipital lobe of PD patients, we directly measured the forward reaction rate constant (kf,ATPase and kf,CK) and cerebral ATP production rate (CMRATP and CMRCK) via the ATPase and CK reactions, respectively, using in vivo 31P MRS in combination with magnetization transfer (MT) technique (31P MRS-MT) [44] in Cohort II.