The Orbit and Optic Nerves
Magnetic Resonance Imaging (MRI) of the orbits and optic nerves has developed into the gold standard of imaging modalities for the evaluation of many soft tissue abnormalities of the orbit. Computed tomography (CT) remains the modality of choice for evaluation of the bony structures of the orbit. MRI is also more flexible, allowing for multiplanar imaging that is not possible with CT. This unit presents a basic protocol for imaging of the orbit. An alternate protocol is presented for the case of dedicated high-resolution surface coil orbital study.
|Amano, Y., Amano, M., and Kumazaki, T. 1997. Normal contrast enhancement of extraocular muscles: Fat-suppressed MR findings. AJNR Am. J. Neuroradiol. 18:161-164.|
|Anzai, Y., Lufkin, R.B., Jabour, B.A., and Hanafee, W.N. 1992. Fat-suppression failure simulating pathology on frequency-selective fat-suppression images of the head and neck. AJNR Am. J. Neuroradiol. 13(3):879-884.|
|Atlas, S.W., Bilaniuk, L.T., and Zimmerman, R.A. et al. 1987. Orbit: Initial experience with surface coil spin-echo imaging at 1.5 T. Radiology 164:501-509.|
|Barakos, J.A., Dillon, W.P., and Chew, W.M. 1991. Orbit, skull base and pharynx: Contrast enhanced fat suppression MR imaging. Radiology 179:191-198.|
|Herrick, R.C., Hayman, L.A., Taber, K.H., et al. 1997. Artifacts and pitfalls in MR imaging of the orbit: A clinical review. Radiographics 17(3):707-724.|
|Kelly, W.M., Paglen, P.G., Pearson, J.A., et al. 1986. Ferromagnetism of intraocular foreign body causes unilateral blindness after MR study. AJNR Am. J. Neuroradiol. 7:243-245.|
|Lagouros, P.A., Langer, B.G., Peyman, G.A., et al. 1987. Magnetic resonance imaging and intraocular foreign bodies. Arch. Ophthalmol. 105:551-553.|
|Mafee, M.F., Ainbinder, D., Afshani, E., and Mafee, R. 1996. The eye, imaging of the globe, orbit, and visual pathways. Neuroimaging Clin. North Am. 6:29-59.|
|Otto, P.M., Otto, R.A., Virapongse, C., et al. 1992. Screening test for detection of metallic foreign objects in the orbit before magnetic resonance imaging. Invest Radiol 27:308-311.|
|Sacco, D.C., Steiger, D.A., Bellon, E.M., et al. 1987. Artifacts caused by cosmetics in MR imaging of the head. AJR Am. J. Roentgenol. 148:1001-1004.|
|Shellock, F.G. 1996. Pocket Guide to MR Procedures and Metallic Objects. Lippincott-Raven, Philadelphia.|
Mafee et al.,
This reference is a general review article focused on imaging of the orbit and visual system.