Abstract
BACKGROUND: Vertical orbital dystopia is a difference in the horizontal level of the orbits often causing head tilt. Almost all of these cases are due to some pathological process including clefting syndromes, tumors, trauma, and craniosynostosis. In a bilateral primary overaction of the inferior obliques there is no head tilt or hyperdeviation in primary gaze, but rather an over-elevation of each eye in the diagnostic action field of the muscle. There are many hypothesized causes.CASE REPORT[S]. A 7 year old male was brought into the eye clinic because his mother noticed an occasional left head tilt. Upon observation it was noted that he had a vertical misalignment of his eyes, with the left being slightly higher than the right. Uncorrected distance visual acuities were 20/30+ OD and 20/25+ OS. During acuity testing he closed the occluded eye and exhibited a variable 30 degree head tilt. Extraocular muscle testing revealed a V-pattern and a grade 2 bilateral overaction of the inferior oblique muscles. This same motility pattern was also demonstrated by his mother. He also had reduced accommodative amplitudes OD and OS. DEM testing showed a ratio that placed him in the 25th percentile based on age. In addition, he was also found to have deuteranopia. All other binocular and pupil testing were within normal limits. Both slit lamp findings and a dilated fundus exam were unremarkable.
CONCLUSIONS. This patient exhibits vertical orbital dystopia associated with bilateral primary overaction of the inferior obliques. A video of the oculomotor pattern and facial asymmetry will be displayed. These conditions will be reviewed. It has been documented in the literature that extraocular muscle irregularities occur with vertical orbital dystopia, specifically superior oblique overaction. However, to the best of our knowledge there has not been a case associated with a bilateral primary overaction of the inferior obliques.