An MRI Study of the Sniffing, Neutral and Extended Head and Neck Positions

"Magnetic resonance imaging (MRI) allows measurement of the axes described to suggest which head and neck position would provide best anatomical alignment to reduce anterior impingement.~All the MRI scans will be conducted using 3.0 Tesla (Optima 750w, GE Medical, Milwaukee, WI, USA) using the cervical spine section of the coil. T2-weighted images in the sagittal plane will be acquired using a fast recovery fast spin echo (FRFSE) technique. The scans will take around two and half minutes and a member of the anaesthetic investigator team will be present to facilitate positional changes and maintain consistency. MRI scanning will be performed in following 3 head and neck positions:~Neutral position, Sniffing position and the Extension position."