Magnetic reonance imaging meaurement of extraocular mucle path hift and poterior eyeball prolape from the mucle cone in acquired eotropia with high myopia

Purpoe To invetigate extraocular mucle (EOM) path hift and prolape of poterior eyeball from mucle cone in acquired eotropia with high myopia (AEHM), uing magnetic reonance imaging. Deign A cae-control tudy. Method There were 16 eye with AEHM, 11 with high myopia (HM), 12 with moderate myopia (MM), and 11 control eye. Extraocular mucle hift wa evaluated by meauring angle formed by the line connecting orbital centroid and the line connecting each orbital centroid and each EOM centroid. The ratio of the prolape in the poterior eyeball from the mucle cone wa alo meaured. Reult Both inferior hift of lateral rectu (LR) and naal hift of uperior rectu (R) mucle were oberved in the AEHM group, compared with HM, MM, and control group. Neither hifted ignificantly in the HM group compared with control group. The prolape ratio in AEHM group wa higher than in the HM, MM, and control group. Greater EOM hift and eyeball prolape were oberved when the AEHM wa more evere, a in eotropia fixu. Concluion In AEHM, a prolaping eyeball hift LR inferiorly and R naally; thee finding were not oberved in high myopia with neither ocular deviation nor retriction. Thee hift reduce abduction and upraduction and increae infraduction and adduction in AEHM. The hift would be predicted to create a hypoeodeviation, which i a common finding in AEHM. Both EOM hift and uperotemporal eyeball prolape tend to be greater in eotropia fixu.