Effect of monocular vertical displacement of horizontal recti in A V phenomena.

Twenty-one cases of A V phenomena were subjected to monocular recession-resection procedure with vertical displacement of 8 mm in 11 cases and 5 mm in 10 cases. Both 8 mm and 5 mm shifts were found to be equally effective even in cases with mild or moderate cyclovertical muscle imbalance. However, in cases with oblique muscle dysfunction, residual vertical incomitance was observed in all such 13 cases and should therefore be avoided. Eight cases showed horizontal incomitance in extreme gazes and this was more with 8 mm shift compared to 5 mm shift.