Axenfeld-Rieger syndrome (ARS) is associated with ocular and systemic anomalies. PITX2 is known to be a major controlling gene in the pathogenesis of ARS and is associated with differentiation in both the neural crest and mesoderm during eye development. A 4-year-old girl with bilateral ARS had 20 prism diopters (PD) of exotropia with 30PD of A- pattern deviation, more than 20PD of dissociated vertical deviation (DVD), and severe superior oblique overaction (SOOA). During surgery we observed that the SO inserted more posteriorly than normal. We believe this finding is one of the abnormal manifestations of the development of the extraocular muscles in ARS.
*Abnormalities, Multiple ; Anterior Eye Segment/*abnormalities ; Child, Preschool ; Eye Abnormalities/*diagnosis/surgery ; Eye Movements ; Female ; Follow-Up Studies ; Humans ; Oculomotor Muscles/*abnormalities/surgery ; Ophthalmologic Surgical Procedures/*adverse effects ; Optic Nerve/abnormalities ; Postoperative Complications ; Sclera/*pathology/surgery ; Syndrome ; Tooth Abnormalities/*genetics

We report two cases of mirror image anomalies in two different pairs of monozygotic twins. In case 1, the twins exhibited mirroring of strabismus and refractive errors. Twin 1 had 35 prism diopters (PD) right intermittent exotropia at distant fixation and myopic anisometropia that was spherical 2.00 diopters more myopic in the right eye. Twin 2 had 35 PD left intermittent exotropia at distant fixation and her left eye was more myopic by - spherical 1.00 diopters. In case 2, the twins were diagnosed with infantile nystagmus with upbeat jerk. Twin 1 exhibited a habitual head turn of 30degrees to the left with dampening of her nystagmus in dextroversion. Twin 2 also exhibited abnormal head position, but in his case the habitual turn was 30degrees to the right. We believe that this is the first report describing mirror imaged intermittent exotropia with anisometropia and infantile nystagmus with opposite abnormal head positions in pairs of monozygotic twins.
Child ; Eye Abnormalities/*diagnosis/genetics/surgery ; Eyeglasses ; Female ; Humans ; Male ; Twins, Monozygotic ; Visual Acuity