[Orbit: Part 1: anatomy, imaging procedures and retrobulbar lesions].

The aim of this 2-part review article on diseases of the orbit is to give the reader an insight into the anatomical structure and an overview of the most important diseases in the area of the eye socket. The main focus is on a description of the imaging procedures and their individual advantages and disadvantages. The most important tumors, trauma and degenerative alterations of the orbit are also described.