Winking owl sign is seen in:

Ans: (b) Vertebral metastasisRef: Radiology ReviewThe winking owl sign, also called absent pedicle sign occurs on plain film when a pedicle is absent on AP view of thoracic or lumbar spine.The term, winking owl sign, where the missing pedicle corresponds to the closed eye, the contralateral pedicle to the other open eye, and the spinous process to the beak of the owl on AP views of the thoracic or lumbar spine, it usually occurs almost always due to a vertebral bony metastasis* causing destruction of the pedicle (closed eye).