Comparison of Postoperative Exodrift after First Unilateral and Second Contralateral Lateral Rectus Recession in Recurrent Exotropia

Abstract

PurposeTo compare postoperative exodrift of the first unilateral lateral rectus (ULR) muscle recession with the exodrift of the second contralateral ULR muscle recession in patients with recurrent small-angle exotropia (XT).MethodsWe evaluated the results of a second ULR muscle recession in 19 patients with recurrent XT with deviation angles under 25 prism diopter (PD), following a first procedure of ULR muscle recession for small-angle XT. Recession of the lateral rectus muscle ranged from 8 to 9 mm. The postoperative motor alignment and degree of exodrift were investigated after the first ULR muscle recession and the second ULR muscle recession in the same patients.ResultsObserved differences in postoperative ocular alignment between the first ULR muscle recession and the second ULR muscle recession were statistically significant at follow-up periods of six months (7.84 ± 4.43 vs. 3.89 ± 3.47 PD), one year (9.58 ± 4.97 vs. 5.21 ± 4.94 PD), and at a final follow-up (21.11 ± 2.98 vs. 7.52 ± 4.06 PD) after surgery (p = 0.006, 0.013, and 0.000). Postoperative exodrift was statistically different between the first and second ULR muscle recessions at three to six months (2.89 ±3.75 vs. 0.63 ± 3.45 PD) and one year to final follow-up (11.52 ± 5.50 vs. 2.32 ± 3.53 PD) (p = 0.034 and 0.000). All of the first ULR muscle recession patients showed XT with deviation angles of more than 15 PD at the final follow-up. Regardless, the surgical success rate (<8 PD) after the second ULR recession was 63.16% (12 patients) among the total amount of patients with recurrent XT.ConclusionsThis study shows that changes in exodrift after a second ULR muscle recession are less than changes after the first URL muscle recession among patients with recurrent XT. A second ULR muscle recession may be a useful surgery for small-angle XT patients with deviation angles of 25 PD or less after a first ULR muscle recession.

Long-term surgical outcomes of bilateral vs. unilateral medial rectus resection for recurrent exotropia

“…However, in our study, the desirable amount of initial overcorrection was 10 PD or less after BMR/UMR resection for recurrent exotropia. These results may be due to the differences in surgical methods [31] or the difference in exodrift rates between the first operation and reoperation [9].…”

“…To date, there is scarce evidence in the literature determining long-term outcomes of BMR resection and/or UMR resection in recurrent exotropia [7,9]. Luk et al [10] and Kim et al [11] evaluated surgical outcomes of BMR and UMR resection in recurrent exotropia; however, only a small number of patients were included in those studies with short durations of follow-up periods.…”

Comparison of outcomes of unilateral recession-resection as primary surgery and reoperation for intermittent Exotropia

“…Resection of contralateral MR might act as a mechanical force, and recession of contralateral LR would change the arc of contact, which in turn would induce a low postoperative exodrift and a large dose-effect ratio of R&R in a reoperation group [ 17 , 20 ]. According to Kim et al’s report, the exodrift changes after a second ULR muscle recession were smaller than those after a first ULR muscle recession in small-angle (< 25 PD) exotropia patients [ 21 ]. They explained that the stability of ULR recession as a second surgery is affected by several factors such as age at the time of surgery and the presence of latent exodeviation [ 21 ].…”

“…According to Kim et al’s report, the exodrift changes after a second ULR muscle recession were smaller than those after a first ULR muscle recession in small-angle (< 25 PD) exotropia patients [ 21 ]. They explained that the stability of ULR recession as a second surgery is affected by several factors such as age at the time of surgery and the presence of latent exodeviation [ 21 ]. In the same manner, our study results might have been affected by these factors.…”