Inferior Oblique MuscleDisinsertion-Myectomy
In this video we demonstrate an inferior oblique disinsertion-myectomy. The left eye is being viewed from its temporal aspect. The inferior part of the globe is to the left and the superior part to the right. After identifying the lateral rectus muscle through the overlying tissues, a fornix incision is initiated by grasping the conjunctiva and Tenonís layers in the inferotemporal quadrant just below the lateral rectus. A small circumferential incision is made through both conjunctival and Tenonís layers using curved Westcott scissors. A combination of blunt and sharp dissection is used to complete the incision and ensure access to the sub-tenonís space. A Jameson muscle hook is slipped under the lateral rectus muscle insertion and the globe is retracted nasally. Further blunt dissection is carried out in a posterior direction, inferior to lateral rectus in order to expose the muscle belly of the inferior oblique. A Graefe hook is then introduced into the subtenonís space, and directed posteriorly along the surface of the sclera until the belly of the inferior oblique muscle is engaged. The subtenonís space is then carefully inspected to ensure that all fibers of the inferior oblique muscle have been isolated. The muscle is then disinserted from the globe using curved Westcott scissors. The cut end of the muscle is grasped and stabilized using toothed forceps. A hemostat is clamped across the muscle 4 mm from its cut end. The distal muscle is resected and the cut end is cauterized using a low-temp disposable cautery. The muscle is released and allowed to retract freely. The conjunctiva will be closed using 6-0 vicryl interrupted sutures.