Patient with long-standing exotropia had strabismus surgery performed using only topical anesthesia. During the surgical procedure, horizontal saccades were measured by electro-oculography. It was found that horizontal saccades were slowed from 240°/sec, preoperatively to 100°/sec following muscle disinsertion. Further saccadic slowing was noted when the disinserted muscle was held taut and was prevented from contracting. This decrease is attributed to limitation of the effective action of the disinserted muscle through posterior attachments to intermuscular membrane and fascia bulbi. Findings following disinsertion may resemble the ocular rotations and saccades noted after release of a suture in early postoperative period after strabismus surgery. Saccadic velocity measurements may be clinically useful in the diagnosis of this problem.
Metz HS, Rice LS. Human Eye Movements Following Horizontal Rectus Muscle Disinsertion. Arch Ophthalmol. 1973;90(4):265-267. doi:10.1001/archopht.1973.01000050267001