Advances in imaging in oculoplastics

Computed anatomical modelling of the optic pathway and oculomotor system using magnetic resonance imaging

This study presents a computer-based tool for three-dimensional (3D) visualization of the optic pathway and oculomotor system using 3D high-resolution magnetic resonance imaging (MRI) datasets from a healthy subject. The 3D models were built as wireframe grids co-registered with MRI sections. First, 3D anatomical models were generated of the visual pathway from the eyeball to the primary visual cortex and of the cranial oculomotor nerves from the brain stem to the extrinsic eye muscles. Second, a graphical user interface allowed individual and group visualization, translation, rotation and zooming of the 3D models in different spatial positions simultaneously with MRI orthogonal cut planes. Educational and clinical applications are also discussed.

Imaging studies for diagnosing Graves' orbitopathy and dysthyroid optic neuropathy

Although the diagnosis of Graves' orbitopathy is primarily made clinically based on laboratory tests indicative of thyroid dysfunction and autoimmunity, imaging studies, such as computed tomography, magnetic resonance imaging, ultrasound and color Doppler imaging, play an important role both in the diagnosis and follow-up after clinical or surgical treatment of the disease. Imaging studies can be used to evaluate morphological abnormalities of the orbital structures during the diagnostic workup when a differential diagnosis versus other orbital diseases is needed. Imaging may also be useful to distinguish the inflammatory early stage from the inactive stage of the disease. Finally, imaging studies can be of great help in identifying patients prone to develop dysthyroid optic neuropathy and therefore enabling the timely diagnosis and treatment of the condition, avoiding permanent visual loss. In this paper, we review the imaging modalities that aid in the diagnosis and management of Graves' orbitopathy, with special emphasis on the diagnosis of optic nerve dysfunction in this condition.