Ocular Misalignment and Motility Limitation in Orbital Tumors

To predict prognosis and aid in the treatment of residual strabismus/ocular misalignment by analyzing the pattern of ocular motility disturbances caused by orbital tumors, and investigating factors associated with the severity of misalignment or motility limitation.

The medical records of 63 patients diagnosed with orbital tumors were retrospectively reviewed. The location, type, and size of the tumor were noted. The limitation of extraocular muscle (EOM) movement was quantitatively scored for upgaze, downgaze, abduction, and adduction by the severity of limitation on a grading scale of 0 to -4. The maximum range of abduction, adduction, supraduction, and infraduction was measured by image analysis based on 9 gaze photographs using the 3D Strabismus Photo Analyzer.

Twenty patients (29%) experienced ocular motility limitations in the affected eye. Twelve patients had orbital tumors situated in the extraconal space (60%), while the other 8 patients (40%) had lesions in the intraconal space. The mean size of extraconal tumors was significantly larger than intraconal tumors (p = 0.010), and there were no significant differences in tumor size between every four groups. In 75% of patients with extraconal tumors, ocular motility was limited toward the action of the adjacent EOM. Conversely, in cases with intraconal tumors, ocular motility was limited toward the opposite direction of the nearest EOM action in 75% cases. Compared with the normal fellow eye, significant limitations of ocular motility were observed in adduction (p = 0.043) and supraduction (p = 0.002). The size of intraconal tumors was the only significant factor related to ocular motility limitation (p = 0.010).

Ocular motility limitations were more common with large extraconal tumors, mostly in the direction of the adjacent EOM. In contrast, ocular motility was limited toward the opposite direction of the nearest EOM with intraconal tumors. Tumor size in the intraconal space was the only significant factor associated with ocular motility impairment.