Prospective evaluation of extraocular motility following double-plate molteno implantation

To determine the incidence and type of extraocular motility disturbance after double-plate Molteno implantation.

In a prospective clinical series, we evaluated preoperative and postoperative ocular motility at 3 and 6 months in 24 eyes of 24 patients undergoing double-plate Molteno implantation. Visual acuity, motility testing, and subjective and objective diplopia were evaluated at each examination.

Within the first 6 months postoperatively, new or worse strabismus developed in 11 (46%) of the 24 study patients. Three of the 11 patients had a generalized restriction of the superior rectus and the superior oblique muscles, all of which persisted 6 months after surgery. Four patients had clinical features consistent with an acquired Brown syndrome, and 6 months after surgery, 3 of the 4 patients had a residual deviation, although the deviation in 1 patient resolved. A superior oblique palsy developed in 3 patients, and a lateral rectus palsy developed in 1 patient. All 4 of the muscle palsies resolved or were resolving during the follow-up period, which ranged from 6 to 12 months.

Extraocular motility disturbances are not rare after double-plate Molteno surgery. Muscle palsies, acquired Brown syndromes, and generalized restrictions occurred in similar proportions.

Patients should be counseled before Molteno surgery concerning the risk of strabismus and diplopia.