Excision of Cyst Associated with Previous Strabismus Surgery

Cystic lesions in the area of previous strabismus surgery and not terribly uncommon.  These cysts can often be observed, but if they are bothersome, they can be removed. It is important to be aware of possible attachment of the cyst to the underlying rectus muscle.  The surgeon should be prepared to possibly detach the rectus muscle and reattach it at the end of the case. 

This is Richard Allen at oculosurg.com.  This video demonstrates excision of a cystic lesion that developed years after a previous strabismus surgery.  The patient has noted slow growth of the lesion.  Traction sutures are placed with 4-0 silk suture beneath the superior and inferior rectus muscles and the eye is placed in an abducted position.   Westcott scissors are then used to incise the conjunctiva overlying the cyst.  The goal is to remove the cyst completely without rupture and conserve conjunctiva.  Sharp and blunt dissection can be carried out along the surface of the cyst, subconjunctivally.  A second incision is then made through the conjunctiva more medially, parallel to the initial incision.  This will leave a small cuff of conjunctiva on the anterior surface of the cyst that can be used as a handle, rather than trying to fixate the surface of the cyst, which may result in rupture.  Dissection the continues carefully along the surface of the cyst.  My approach to dissection around cysts is to dissect until it is difficult, then move to another area, until you have gotten completely around the cyst.  Again, the cuff of retained conjunctiva on the surface of the cyst is used for fixation, rather than using the cyst wall for fixation which may result in rupture of the cyst.  As this is s a cyst associated with a previous strabismus surgery, there is the possibility of attachment of the cyst to the rectus muscle.  As is noted here, dissection around the cyst has resulted in detachment of the medial rectus muscle.  It is important to recognize this and tag the muscle with a suture.  A double armed 5-0 Vicryl suture on a spatula needle is used to engage the muscle.  The cyst can then be dissected from the muscle.  The muscle is then reattached to the globe.  Calipers are used to measure approximately 6 mm from the limbus and the suture are placed partial thickness through the sclera.  Tying the sutures places the muscle in the appropriate position.  The conjunctiva is then closed with interrupted 7-0 Vicryl sutures in a buried fashion.  Forced ductions are checked and the eyes appear to be aligned.   Antibiotic ointment is placed in the eye and the patient will follow up in approximately one week for reevaluation.