IGF1 and Strabismus: Sustained delivery of IGF-1, and the potential slow and gradual changes associated with such delivery, would avoid the large single change in eye alignment often associated with surgical intervention and, therefore, allow plasticity mechanisms in the visual system and/or ocular motor system to adapt to the change in eye alignment.18, , –21 This conceptually has interesting implications for strabismus treatment, and experimental animal models allow this to be studied in more detail.