Clinical Features of Crowded Orbital Syndrome on Magnetic Resonance Imaging.

We have previously reported strabismus due to mismatch of orbital volume and globe as 'crowded orbital syndrome' (COS). In this study we have used magnetic resonance imaging (MRI) to investigate its clinical features. This has revealed that a globe with a similar axis occupies a larger volume in the orbit in patients with COS than in controls without strabismus. This suggests that strabismus with high myopia may easily occur in those with relatively small orbits and axial elongation. In acquired esotropia and/or vertical strabismus, a mismatch of orbital volume and globe axis should be investigated with MRI.