Vertical rectus muscle transposition and botulinum toxin (Oculinum) to medial rectus for abducens palsy.

Ten adult patients developed sixth-nerve palsy after trauma or a cerebral tumor. No clinical evidence of recovery of function was noted by at least 8 months after onset. All patients underwent total transposition of the superior and inferior rectus muscle insertions to the area of the lateral rectus insertion, accompanied by botulinum toxin (Oculinum) injection of the ipsilateral medial rectus. These patients developed a mean diplopia-free field of 51 degrees, with a diplopia-free field in the abducted field of 20 degrees. This procedure involved surgery on only two rectus muscles, but the results compared favorably with surgical strategies involving three rectus muscles. Thus, the risk of developing anterior segment ischemia was greatly reduced.