SUMMARY
The study goal was to compare the results of two different techniques of surgical weakning of superior oblique muscle for “A” anisotropia. A retrospective review was conducted on data of 40 cases operated for horizontal deviation associated to “A” pattern up until 25 pd. Patients were divided in two groups according to surgical technique: partial posterior tenectomy (TPP) and muscle desinsertion (Ds). The results were compared considering the inicial amount of “A” pattern, tipes of horizontal deviation and amount of surgical correction of inicial “A” pattern. Correlation between initial “A” pattern and surgical correction was also analyzed. There was no statistical difference between the two groups when considering the analyzed parameters. Mean values of surgical correction plus standard deviation were: for TPP (26 cases): 12.8 ± 6.7 and for Ds (14 cases), 12.9 ± 5.2 pd. Correlation between initial amount of “A” pattern and surgical correction was achieved for the TPP group but not for the Ds group.