Vessel-Sparing Strabismus Surgeries

A rare but potentially serious complication of strabismus surgery is anterior segment ischemia (ASI). The incidence of ASI due to strabismus surgery is reported to be approximately 1 in 13,000 cases [1]. ASI can occur after strabismus surgery because disinsertion of rectus muscles disrupt anterior ciliary vessels that supply the anterior segment via the episcleral limbus plexus, intramuscular circulation within the ciliary body, and major arterial circle in the iris root [2]. Iris filling defects on iris angiography have been found more commonly after surgery on vertical rectus muscle involving muscle disinsertion (i.e., vertical tenotomy or resection) [3]. Iris filling defects can be detected utilizing iris angiography after intravenous injection of indocyanine green as shown in Fig. 20.1.