Abstract
Purpose::
This imaging atlas provides the first highly extensive review of the complex orbital bony anatomy seen on CT. The detailed images demonstrate landmarks and anatomical variants to aid in more accurate clinical diagnoses.
Methods::
A review of CT scans in adults with normal anatomical variants was performed. Five scans selected to highlight specific bony anatomy, and obtained in 1 mm thin axial sections. These were reconstructed in the coronal and sagittal planes and supplemented with a 3-D volume image. The CT scans were paired with colored schematics and detailed dimensional data.
Results::
Orbital images were divided into 5 regions and labeled accordingly: orbital rim, medial orbital wall, orbital floor, lateral orbital wall and orbital roof. Special detail was given to integral bony structures that could be identified on CT and their particular relevance to bony pathology. In particular, areas of extension of sinus disease into the orbit, notches and foramen/fissures where neurovascular bundles course, lines of sutures (weakness), important bony prominences of ligament insertions, and fossas, sulci, and canals important for surgical landmarking.
Conclusions::
Precise and accurate knowledge of variants of normal anatomy and dimensions facilitates detection and surgical reconstruction of bony orbital lesions. To our knowledge, anatomic orbital landmarks and variants have never been demonstrated before in a complete imaging atlas to be used for clinical correlation.
Keywords: comparative anatomy • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • orbit