b catenin inhibitor Patients with both primary gaze consecut

Patients with both primary gaze consecutive esotropia (Fig. 1) and consecutive exotropia (Fig. 2) showed significantly less vertical deviation postoperatively compared with preoperative measurements (p < 0.01).
Discussion The treatment of constant vertical tropia associated with consecutive horizontal deviation, in the absence of oblique muscle dysfunction, dissociated vertical deviation, or extraocular muscle palsy, has been enigmatic. Previously, Pratt–Johnson and Tillson determined 5 PD to be an appropriate baseline and indicator of whether surgical intervention may be warranted. The findings in our report are dramatic in that the vertical deviation present preoperatively in all patients with consecutive horizontal deviation underwent spontaneous b catenin inhibitor with surgical treatment of the horizontal component alone in all cases. Previously, it had been documented that hypertropia in the setting of intermittent exotropia was correctable solely with treatment aimed at the exotropia. However, to date, there are no case reports of resolution of vertical deviation with correction of consecutive horizontal strabismus. We have described the resolution of the vertical component of tropias in patients whose indication for surgery dealt with horizontal deviation alone. Our data suggests that additional surgery intended to correct the component of vertical deviation may not be necessary in some patients with consecutive horizontal deviation. Previous investigators have hypothesized a linear relationship between the millimeters of vertical offset of the horizontal muscles and the shift in prism diopters. However, our study shows this relationship to be nonlinear in patients who had horizontal surgery alone. Therefore, patients with consecutive horizontal deviation with vertical tropia may be better served with horizontal muscle surgery alone rather than a combination surgery involving both horizontal and vertical muscles. There is no consensus in the literature for the effect that was observed in this study regarding correction of vertical tropia in patients undergoing surgery on horizontal extraocular muscles alone. In our patients, hypertropia was corrected by horizontal muscle surgery alone. We found these results to hold true even in patients with consecutive strabismus with large hypertropia (at least 10 PD) in whom there was consideration of vertical rectus muscle surgery. The potential explanation may involve both mechanical and extraocular muscle factors. Pulley heterotopy and pulley instability have both been linked to imcomitant strabismus. Costa et al. reported and extended study that suggested functionally distinct superior and inferior zones within the horizontal rectus extraocular muscles in both humans and monkeys. Recently, functional evidence for differential compartmental activation of the human horizontal rectus extraocular muscles was obtained from magnetic resonance imaging during ocular counter-rolling induced by head tilt, convergence and vertical fusional vergence. Shin et al. extended results to active contraction. Rabinowitz and Demer found that the path lengths of the horizontal rectus EOMs in intermittent and alternating esotropia and exotropia were not abnormal. This possibility could not be tested in our study. We could find no study that addressed surgical treatment of solely horizontal muscle for consecutive horizontal strabismus with vertical tropia. In our study, surgical correction of consecutive horizontal deviation successfully resolved vertical tropia that was unrelated to oblique muscle dysfunction, manifest or latent dissociated vertical deviation, or extraocular muscle palsy, and was not accompanied by subjective torsion or compensatory head posture. Based on our findings, we recommend that patients with consecutive horizontal deviation and hypertropia receive surgical alignment of the horizontal muscles alone. Only if hypertropia does not resolve should vertical alignment be undertaken. Our study confirms that horizontal muscle surgery alone can lead to resolution of hypertropia in association with consecutive horizontal strabismus.