Abstract:AIM: To investigate the therapeutic effects of simultaneous horizontal and vertical operations on dissociated vertical deviation (DVD) associated with other deviations. METHODS: Forty-five cases of DVD with horizontal and torsional strabismus underwent combined operation were collected retrospectively. All clinical records were analyzed. All patients were followed up for 6 to 24mo. Wilcoxon signed-ranks test was performed to evaluate the changes of vertical and horizontal deviation. χ2 test was used to evaluate the changes of binocular visual function. RESULTS: Forty-five cases included 36 patients with intermittent exotropia and binocular inferior oblique overaction (IOOA), 5 patients with concomitant esotropia and binocular IOOA, 4 patients with intermittent exotropia and monocular superior oblique palsy. The superior rectus recession (SRR) combined with horizontal rectus recession and the myectomy of inferior oblique or anterior transposition were operated simultaneously to correct all types of strabismus. There were 43 cases who achieved normal eye position in vertical direction, while 2 cases were with undercorrection of 5Δ to 6Δ. In patients with horizontal strabismus, 2 cases of exotropia were with overcorrection of 6Δ to 8Δ, 1 case of esotropia was with undercorrection of 6Δ, and 1 case of monocular superior oblique palsy with compensatory head posture was not significantly improved. The binocular visual function of most patients recovered after operation. The difference of the binocular visual function and eye position were significant compared with that before operation (P<0.05). CONCLUSION: The simultaneous operation on DVD with horizontal and torsional strabismus is successful.