[Effectiveness of oblique recession with and without resection of horizontal recti in A and V patterns (author's...

Report on 50 patients (17 V-esotropia, 6 V-exotropia, 17 A-esotropia, 10 A-exotropia) who were re-examined between six weeks and six months after oblique recession without/with resection of horizontal recti (procedure of Bietti, Boyd, Lavat et al.). The reduction in A and V patterns achieved varied considerably and nd was unpredictable. In 45% of the patients there was no change at all, or at most a slight change of less than 3%. Thus, the procedure appears to be less effective than oblique muscle surgery or vertical transposition of horizontal recti. Nevertheless, the oblique recession-resection procedure might be of limited use of torsional effects induced by transposition of horizontal recti are undesirable for functional reasons. A curious finding was the reduction in A and V patterns in three out of five patients who were treated with oblique recessions without/with resection in the opposite direction.