To the Editor.
—Once again an article1 has been published proclaiming the benefits of an operation to correct overactive inferior oblique (OAIO) muscles.Inferior oblique muscle surgery is so successful because OAIO is a condition that disappears with maturity. Unfortunately, today's pediatric ophthalmologists do not do many motility examinations on adults and so are not struck by the observation that adults do not have OAIOs. Almost 40 years ago Scobee2 referred to the "normal overaction of the inferior oblique muscle" due to the interruption of fusion by the nose on lateral gaze. Even then it was noted to be more common in tropic patients with no fusion. An OAIO is never seen in adults unless it is secondary to a damaged ipsilateral superior oblique muscle. The OAIO responds to so many different weakening procedures because it also goes away without surgery. Except in rare instances, the OAIO should
Fleming AW. 'Normal' Overaction of Inferior Oblique Muscles. Arch Ophthalmol. 1989;107(8):1113. doi:10.1001/archopht.1989.01070020179003