Anatomy and surgery of the inferior oblique muscle: Recent findings

Background. Surgery of the inferior oblique muscle (10) has undergone signi ficant changes in the past 160 years. Many investigators have contributed t o our understanding of the action of this muscle and to the surgical option s that have developed. This article reviews the history of 10 surgery with particular emphasis on the anterior transposition procedure. Methods. Anato mic and physiologic studies on the neurofibrovascular bundle of the 10 are presented. Results:The ligamentous structure of the neurofibrovascular bund le of the 10 provides the ancillary origin for the posterior temporal fiber s of the 10 when its insertion is transposed anteriorly. Discussion: Recent anatomic findings have helped explain the effects of the anterior transpos ition procedure and allow further development of our surgical armamentarium for vertical strabismus problems. Further nasal transposition of that inse rtion should reduce or eliminate the incidence of the antielevation syndrom e. If transposed far nasally, the 10 could convert to an intorter, as well as to an antielevator and tonic depressor.