Contralateral lateral rectus recession versus recess-resect for recurrent exotropia after unilateral recess-resect

Analysis of postoperative exodrift according to surgical methods for intermittent exotropia

PURPOSE

This study aimed to compare the periods for exodrift stabilization and the long-term surgical outcomes among different surgical methods in intermittent exotropia.

METHODS

The medical records of 350 patients who had undergone intermittent exotropia correcting surgery [unilateral lateral rectus recession-medial rectus resection (R&R, n = 221), bilateral lateral rectus recession (BLR, n = 51) and unilateral lateral rectus recession (ULR, n = 78)] with a postoperative follow-up period of 1.5 years or more were retrospectively reviewed. The deviation angles every 6 months after surgery, periods of exodrift stabilization and surgical outcomes were analysed. The period of postoperative exodrift stabilization was defined as when exodrift was no longer significantly different from that at the next visit (p > 0.05). An alignment of 5 PD (prism diopters) esotropia to 10 PD exotropia at a distance and near fixation was considered surgical success.

RESULTS

The mean angle of exodeviation was significantly different among surgical procedures at postoperative 1 month (BLR > ULR > R&R, p < 0.001); however, there were no differences among the procedures at 6 months (p = 0.088). The periods of exodrift stabilization were 6 months after ULR, 1 year after BLR and 4.5 years after R&R. The surgical success and reoperation rates did not show significant differences among procedures at the final follow-up.

CONCLUSION

Patients undergoing R&R showed smaller exodeviation shortly after surgery but required a longer period to stabilize the exodrift. Following ULR, exodeviation was larger in the early postoperative period, but the exodrift was stabilized earlier. Therefore, the long-term surgical outcomes were similar among ULR, BLR and R&R.

Comparison of sensory outcomes in patients with successful motor outcome versus recurrent exotropia after surgery for intermittent exotropia

Here, we compared sensory outcomes between patients with successful motor outcomes and recurrent exotropia after intermittent exotropia surgery. We retrospectively analyzed 303 patients who underwent surgery for intermittent exotropia, divided into two groups: successful motor outcome defined as an alignment between 10 prism diopters (PD) exodeviation and 5PD esodeviation at the final follow-up (Group A, n = 177) and residual or recurrent exotropia defined as exodeviation > 10 PD (Group B, n = 126). Preoperative and postoperative (at final visit) sensory outcomes were compared using the Titmus stereotest and distance Worth 4-dot test. Stereoacuity significantly improved postoperatively in both successful motor outcome group (Group A) and residual or recurrent exotropia group (Group B). However, stereoacuity did not differ between groups preoperatively and postoperatively. On the other hand, fusion rates for the Worth 4-dot test were significantly higher in group A than in group B, preoperatively and postoperatively, and significantly increased postoperatively only in group A. Therefore, the distance Worth 4-dot test may be useful for evaluating postoperative prognosis and preoperative sensory status.

Initial overcorrection after surgery for intermittent exotropia in children less than 4 years old: Comparison with older children

Purpose

While initial overcorrection after exotropia-correcting surgery is widely accepted for a favorable long-term outcome, some have not advocated such overcorrection in younger children owing to concerns regarding rapid deterioration of bifixation ability. This study aimed to evaluate the relationship between initial overcorrection after intermittent exotropia surgery and the surgical outcome in patients aged <4 years.

Methods

In this retrospective study, 391 patients who had undergone surgery for intermittent exotropia were classified into two groups according to the age at surgery: <4 years old (group Y [young], 130 patients) and 4–16 years old (group O [old], 261). The patients were subdivided into three groups according to the angle of deviation at postoperative 1 week: esophoria-tropia (ET) ≥10 prism diopters (PD) (subgroup I), ET 1–9 PD (II), and orthotropia or exophoria-tropia (XT) (III). We compared the surgical outcomes between the two groups and among subgroups; then, we analyzed consecutive esotropia patients.

Results

The mean exodeviation was smaller in the order of subgroup I, II, and III at every postoperative visit (p<0.05) in group Y but showed no difference among subgroups after 2 years in group O. Consecutive esotropia occurred at 1 month, postoperatively, in 6.9% and 2.6% of the patients in groups Y and O (p = 0.133), respectively. However, it persisted in two and one patient in groups Y and O, respectively, until the last visit.

Conclusion

Early overcorrection after intermittent exotropia surgery was a safe and desirable result in terms of motor outcome in children aged under 4 years, as well as for children aged between 4–16 years.

Unilateral lateral rectus recession is an effective surgery for intermittent exotropia in young children

Background

Different surgical methods have been suggested for the correction of intermittent exotropia. Unilateral lateral rectus recession has been described as a surgical alternative for small and moderate-angle exotropia. In general, previous studies did not focus on the outcomes of unilateral lateral rectus recession in young children with intermittent exotropia. The purpose of this study is to evaluate the surgical outcomes of unilateral lateral rectus recession in the treatment of moderate-angle exotropia (≤ 25 PD (prism diopters)) in children.

Methods

The charts of all patients younger than 12 years of age with moderate-angle exotropia (up to 25 PD) who were operated during the years 2006–2018 were retrospectively reviewed. Fifty-eight patients underwent unilateral lateral rectus recession and had a minimum follow up of 6 months. The angle of exotropia (PD) before and after surgery and the success rate were documented.

Results

Mean age at surgery was 6.4 ± 1.9 (range 3.5–11.0) years. Exotropia improved from a preoperative angle of 21.4 ± 4.0 PD to 3.5 ± 5.9 PD postoperatively (p < 0.001). Success rate, defined as deviation of ≤ 10 PD, was achieved in 86.2%. There were 2 (3.4%) cases of overcorrection (consecutive esotropia). There were no intra- or postoperative complications. The mean follow-up duration after surgery was 2.3 ± 1.7 years.

Conclusions

In children with moderate angle exotropia, good postoperative success rate was achieved by performing unilateral lateral rectus recession.

Risk factors associated with poor outcome after medial rectus resection for recurrent intermittent exotropia

PURPOSE

To describe characteristics of recurrent intermittent exotropia after bilateral lateral rectus (BLR) recession, and identify factors associated with poor outcome after unilateral medial rectus (MR) resection for recurrent intermittent exotropia.

METHODS

We retrospectively reviewed 124 patients who have undergone unilateral MR resection for recurrent intermittent exotropia after BLR recession. Patients were followed for at least 2 years after MR resection. Clinical characteristics and risk factors associated with poor outcome after unilateral MR resection were evaluated. Successful outcome was defined as distant deviation within the range of 4 prism diopters (PD) esotropia and 10 PD exotropia at last visit after MR resection.

RESULTS

Among 124 patients, 50 patients (41.1%) were male, and the mean age at the time of MR resection was 9.5 ± 3.1 years. The average follow-up period after MR resection was 43.8 ± 23.7 months. Forty-seven patients (37.9%) were classified to have poor outcome at last visit, and 29 patients (23.4%) underwent third operation. None of the patients was overcorrected after MR resection. Multiple logistic regression analyses showed that distant deviation at post-operative 3 months and male gender were associated with poor outcome (OR 1.49; 95% CI 1.27-1.73; P < 0.001, and OR 5.19; 95% CI 1.42-18.98; P = 0.013, respectively).

CONCLUSION

Ocular deviation at 3 months after unilateral MR resection for recurrent intermittent exotropia may play a valuable role in anticipating poor outcome. Patients whose exotropia exceeded 9 PD at distance at 3 months' follow-up tended to recur while those whose exotropia remained below 9 PD at distance showed a stable disease course.

Factors Associated with the Prognosis after Operation in Children with Recurrent Intermittent Exotropia

BACKGROUND

To describe factors affecting the prognosis after operation for recurrent intermittent exotropia (X[T]) in children.

METHODS

Clinical records of 50 patients who underwent operation for recurrent X(T) by a single surgeon were reviewed. The age at diagnosis of X(T), and first and second operations, deviation angle at distance and near, surgical method, concurrent vertical strabismus, stereoacuity, and Worth's Four Dot (W4D) examination before reoperation were analyzed, along with the postoperative deviation angle. A successful surgical outcome was defined as orthophoria, esodeviation ≤ 5 prism diopters, or exodeviation ≤ 10 prism diopters at distance.

RESULTS

Among the 50 recurrent exotropes who underwent surgery and were followed up for more than 1 year postoperatively, 13 showed recurrent exotropia and 1 showed consecutive esotropia. The mean age at reoperation was 8.49 ± 2.19 years, and the mean duration of postoperative follow-up was 27.78 ± 12.02 months. Good near fusion before reoperation was a significant factor in the success of surgery (P = 0.006). Smaller postoperative deviation angle measured immediately and 2 months after surgery were related to smaller final deviation angle (P = 0.027 and P = 0.022, respectively).

CONCLUSION

Peripheral suppression lowers the success rate of operation for recurrent X(T) in children. Overcorrection rather than orthotropia should be the target of immediate postoperative deviation angle. Peripheral suppression status and immediate and 2-month postoperative deviation angle may be important clues for predicting the final result of operation for recurrent X(T).

Bilateral Lateral Rectus Recession for the Treatment of Recurrent Exotropia after Bilateral Medial Rectus Resection

PURPOSE

To evaluate the efficacy of bilateral lateral rectus muscle recession (BLR) to treat recurrent exotropia after bilateral medial rectus muscle resection (BMR).

METHODS

Twenty-four patients who underwent BLR for recurrent exotropia and were followed up for more than 6 months were included in this retrospective study. All of them had prior BMR. The angle of deviation, success rates, near stereopsis, and surgical effect of BLR were evaluated. Surgical success was defined as postoperative deviations ≤10 prism diopters (PD).

RESULTS

The overall mean follow-up time after reoperation for patients was 24.13 ± 15.01 months (range 6-60 months). The mean angle of deviation at distance was significantly reduced from -37.75 ± 14.93 PD to +1.50 ± 6.43 PD (p < 0.001). Twenty-two (91.6%) of 24 patients had successful outcomes, 1 (4.2%) had overcorrection, and 1 (4.2%) had undercorrection at the last follow-up. Improved stereopsis after reoperation was observed in 78.3% (18/23) of the patients. The mean surgical effect was 2.78 ± 0.71 PD/mm.

CONCLUSION

Based on our results, BLR could be an effective and safe method for treating recurrent exotropia after a moderate to large amount of BMR.

Outcomes of bilateral lateral rectus recession in treatment of recurrent exotropia after bilateral medial rectus resection

PURPOSE

To report the results of bilateral lateral rectus muscle recession for recurrent exotropia in cases where the primary surgery was a bilateral medial rectus resection.

METHODS

Retrospective chart review of 15 subjects who completed 6 months of follow-up. Data collected included patients' demographics and pre- and post-operative measurements of ocular alignment and motility. Surgical nomogram used was the same nomogram we use for primary cases of exotropia.

RESULTS

At 6-month follow-up, 73.3% of cases had a successful surgical outcome (defined as 8 PD of esotropia to 10 PD of exotropia). In addition, recession of lateral rectus muscles against the previously resected medial recti did not result in a significant increase in the limitation of abduction.

CONCLUSION

Bilateral lateral rectus recession using standard surgical tables is a safe and effective method for treating recurrent exotropia following bilateral medial rectus resection. Even large primary resections up to 12 mm do not seem to affect the results of bilateral lateral rectus recession.

Comparison of Long-term Surgical Outcomes Between Unilateral Recession and Unilateral Recession-Resection in Small-Angle Exotropia

PURPOSE

To compare the surgical outcomes of unilateral lateral rectus recession-medial rectus resection (RR) and unilateral lateral rectus recession (ULR) for intermittent exotropia of ≤20 prism diopters (PD).

DESIGN

Retrospective, nonrandomized clinical study.

METHODS

A total of 130 children with intermittent exotropia of ≤20 PD who underwent unilateral RR or ULR of 10 mm were included. Patients were observed for at least 2 years. Success rates, cumulative probabilities of success, and factors related to recurrence and overcorrection were evaluated.

RESULTS

The mean follow-up duration after surgery was 3.1 ± 1.0 years in the RR group and 3.6 ± 1.6 years in the ULR group. In the RR group, 38 of 61 patients (62%) had ocular alignment within 10 PD of exophoria/tropia and 5 PD of esophoria/tropia; 18 patients (30%) had recurrence, and 5 (8%) had overcorrection. In the ULR group, 26 of 69 patients (38%) had successful alignment, 41 patients (59%) had recurrence, and 2 patients (3%) were overcorrected. At 6 months after surgery, the success rate was significantly higher in the ULR group (RR 61%; ULR 78%, P = .039), but it became comparable after 2 years (RR 60%; ULR 52%, P = .370). At the final examination after a mean duration of 3 years, the recurrence rates were lower in the RR group (30% vs 59%, P = .001), and the overcorrection rates were comparable (8% vs 3%, P = .252).

CONCLUSION

Unilateral RR resulted in more successful alignment and lower recurrence compared to ULR for the treatment of small-angle intermittent exotropia of ≤20 PD.

Comparative study of lateral rectus recession versus recession-resection in unilateral surgery for intermittent exotropia

PURPOSE

To compare the outcomes of unilateral lateral rectus recession to unilateral recession-resection in the treatment of patients with intermittent exotropia.

METHODS

The medical records of patients with intermittent exotropia with exodeviation of 20(Δ) to 25(Δ) who underwent unilateral lateral rectus recession or recession-resection at a single center from 2002 to 2010 were retrospectively reviewed, and surgical outcomes between groups were compared.

RESULTS

Of 70 patients, 37 underwent lateral rectus recession; 33, recession-resection. The mean preoperative exodeviation was 22.2(Δ) ± 2.1(Δ) at distance and 22.3(Δ) ± 3.3(Δ) at near in the lateral rectus group and 24.5(Δ) ± 1.4(Δ) at distance and 26.4(Δ) ± 3.6(Δ) at near in the recession-resection group. Successful surgical outcome was defined as esodeviation of ≤5(Δ) to exodeviation of ≤10(Δ) at distance in primary position. The mean follow-up period was 37.1 months in the lateral rectus group and 44.6 months in the recession-resection group (P = 0.078). The surgical success did not differ significantly between groups at the final follow-up (45.9% in the lateral rectus group and 39.4% in the recession-resection group; P = 0.215). However, posteroperative overcorrection was less common in the lateral rectus group through 12 months' follow-up.

CONCLUSIONS

Surgical outcomes at a mean of 3.4 years did not differ significantly between groups. In our study cohort, unilateral lateral rectus recession showed a low risk of overcorrection in the treatment of mild to moderate angle exotropia.

Hyperopic refractive errors as a prognostic factor in intermittent exotropia surgery

Purpose: To evaluate and compare surgical outcomes with respect to refractive errors in strabismus surgery for the treatment of intermittent exotropia (IXT).

METHODS

The medical records of patients with IXT who were treated by one surgeon from January 2005 and June 2011 were reviewed. Three hundred and thirty-three IXT patients were included and divided into three groups according to preoperative refractive error: IXT with hyperopia (group I), IXT with emmetropia (group II), and IXT with myopia (group III). The surgical outcomes with respect to sensory and motor criteria were compared among the three groups.

RESULTS

The surgical success rates according to motor criteria and sensory and motor criteria combined were higher in groups I (29 patients) and III (124 patients) than in group II (180 patients) at postoperative 3 and 6 months and at the last follow-up. Stereopsis was significantly better in groups II and III than in group I preoperatively (P=0.002 by one-way analysis of variance test); however, the difference was not significant postoperatively. Twenty patients in group I (69.0%) were prescribed undercorrected hyperopic spectacles postoperatively, while only 22 patients in group III (17.7%) were prescribed spectacles with more myopic power than their refractive errors.

CONCLUSION

In the surgical treatment of IXT, hyperopia was not an indicator of poor prognosis. Taking into consideration the age effect, follow-up period after IXT surgery, and stereopsis improvement, hyperopic refractive error is rather a good prognostic factor.

Unilateral medial rectus resection for the treatment of recurrent exotropia in children

PURPOSE

To investigate the outcomes of unilateral medial rectus resection (UMR-res) for the treatment of small to moderate angles of recurrent exotropia in children followed up for a minimum of 6 months.

METHODS

This study is a retrospective, consecutive, interventional case series in which 48 children who underwent UMR-res (range 4.0-7.5 mm) for recurrent exotropia [range 12-25 prism diopters (PD)] between January 2009 and February 2013 were enrolled. Of these 48 children, 32 had recurrent intermittent exotropia, and 16 had recurrent constant exotropia. A successful surgical alignment was defined as +5 to -10 PD of orthophoria in the primary position while viewing distant or near targets.

RESULTS

At a mean follow-up of 12 months, the surgical success rate was 75 % (36/48), and the undercorrection rate was 25 % (12/48). No patient exhibited overcorrection. The success rates of the UMR-res in the recurrent intermittent exotropia group and recurrent constant exotropia group were 78 % and 69 %, respectively, and were not significantly different (P = 0.50). In the initial surgical procedure groups, the success rates of patients with bilateral lateral rectus recession, unilateral lateral rectus recession, and unilateral lateral rectus recession combined with medial rectus resection were 81.8 % (18/22), 81.25 % (13/16), and 50 % (5/10), respectively. The surgical success rates did not differ among these three groups (P = 0.122).

CONCLUSION

Based on our results, UMR-res would appear to be an effective and safe procedure for the treatment of intermittent or constant recurrent exotropia of ≤25 PD in children.

Surgical treatment for residual or recurrent strabismus

Although the surgical treatment is a relatively effective and predictable method for correcting residual or recurrent strabismus, such as posterior fixation sutures, medial rectus marginal myotomy, unilateral or bilateral rectus re-recession and resection, unilateral lateral rectus recession and adjustable suture, no standard protocol is established for the surgical style. Different surgical approaches have been recommended for correcting residual or recurrent strabismus. The choice of the surgical procedure depends on the former operation pattern and the surgical dosages applied on the patients, residual or recurrent angle of deviation and the operator's preference and experience. This review attempts to outline recent publications and current opinion in the management of residual or recurrent esotropia and exotropia.