Motility disturbances after Molteno implants

Molteno implants are gaining wide acceptance for refractory glaucoma in both children and adults. Such surgery led to vertical strabismus in three patients. Two children developed an inability to elevate the globe after Molteno implants were placed superiorly. One adult, whose Molteno implant was placed inferiorly, could not fully depress the globe postoperatively, and experienced vertical diplopia. This complication of Molteno implants was explored using forced duction testing and surgery. We feel a likely explanation for this is a Faden or posterior fixation suture effect induced by scarring under the rectus muscle. Patients undergoing this surgery should be counseled about possible postoperative diplopia, an especially devastating complication when the implant is placed inferiorly.