Surgical results were compared in a small series of 11 cases of V pattern exotropia regarding simple bilateral lateral rectus recessions (with supraplacement) versus bilateral lateral rectus recessions combined with inferior oblique weakenings. None of the cases demonstrated inferior oblique overaction. Up-down comitance was considerably better in those cases that had inferior oblique surgery.
Billet E, Freedman M. Surgery of the Inferior Oblique Muscles in V Pattern Exotropia. Arch Ophthalmol. 1969;82(1):21-22. doi:10.1001/archopht.1969.00990020023006