RESULTS OF SURGICAL THERAPY OF THE RETRAC TION SYNDROME OF STILLING-TURK-DUANE

Background The typical signs of the retraction syndrome (Stilling-Turk -Duane) are abnormal head posture, marked limitation of abduction, sli ght limitation of adduction and convergence, which are always accompan ied by retraction of the globe, narrowing of the palpebral fissure, ve rtical deviation and increased intraocular pressure upon adduction. Al l signs are explicable by the cocontraction of the horizontal muscles or the failing relaxation of the lateral rectus muscle. Abnormal syner gistic innervation occurs when in aplasia of the abducens nerve the la teral rectus muscle receives abnormal innervation by branches of the o culomotor nerve, which may also be accompanied by fibrosis of those pa rts of the muscle that are not innervated. This pathogenesis gives rea son for the variety of signs and reduces the value of all classificati ons defined by electromyography. It seems more sensible to classify th e retraction syndrome with respect to the direction of the head turn. Patients and methods According to this classification, the left-sided retraction syndrome with head turn in adduction made up the largest, t ypical group (58%) in our study (n=82). All other groups represented l ess than 12%. The main goal of surgical therapy was the elimination of the abnormal head turn, the vertical deviation and the retraction. Ba sed on the pathogenesis, only recessions of one or both horizontal mus cles were performed and strengthening procedures were avoided. Results Concerning the horizontal and vertical deviation and the head posture , the surgical results of this procedure were satisfactory. Preoperati vely less than 10% in all groups showed a deviation at distance of 5-d egrees and less, whereas 6 month after surgery this small angle was ob tained in over 60% in all groups. While preoperatively less than 20% i n all groups had a head turn of 10-degrees and under at distance fixat ion, 6 months after surgery this was demonstrated in over 70% of all o ur cases. Conclusion The main goal of surgery is the reduction of the abnormal head posture. the retraction with narrowing of the palpebral fissure and the vertical deviation. Only recessions of one or both hor izontal muscles can achieve the necessary mechanical relief. In cases with marked retraction one must avoid strengthening procedures.