Parasagittal oblique (interlaminar) view (PSO view). L3/4 space mid-screen. Suboptimal view, yet saw-tooth pattern of lamina and interspaces easily identified. Vertebral body cortex between lamina faintly seen at 10 cm depth. The ligamentum flavum was not visible in this patient. In the PSO view, with an interspace centred mid-screen, mark the skin at each level during the prescan. ESM, erector spinae muscle; ITS, intrathecal space; Lamina, L4 lamina; VB, vertebral body. Informed consent was obtained from the patient for using clinical images.