Graduated recession of the superior oblique muscle JORGE

Tenotomy or tenectomy is at present the most usual procedure for diminishing the action of the superior oblique muscle (SO). Hughes and Bogart (1942) described the recession of the trochlea but this procedure has not been generally accepted. Foster (1946) performed a recession of the SO after temporary division of the superior rectus with a reasonably good result, but his technique was apparently not tried by other ophthalmic surgeons. Fink (I962), in his book on surgery of the vertical muscles, considered tenotomy to be the most satisfactory operation for reducing the effect of an overactive SO. Ciancia and Prieto-Diaz (1970) described a recession of the SO without severing the superior rectus and reported on I 2 patients with an A phenomenon submitted to bilateral surgery. The amount of recession was the same in all patients. Duke-Elder and Wybar (I973) mentioned recession of the SO when dealing with techniques but not in reference to treatment of the A phenomenon. Stanworth (I968) commented on the difficulty of having to re-attach the SO tendon but concluded that this could be done securely. Overaction of the SO can be bilateral, as seen in some patients with horizontal strabismus and an A phenomenon. It can, however, be unilateral, as observed in some cases with a vertical deviation in the primary position. In both situations a weakening procedure of the SO, either bilateral or unilateral, may be the surgery of choice. The purpose of this paper is first, to describe a technique which allows a graduated recession of the SO; and secondly, to evaluate the results so obtained in cases of A phenomenon or vertical strabismus.