Plication as an alternative to resection in horizontal strabismus: A randomized clinical trial

Analysis of temporal changes in thickness from conjunctiva to sclera after plication of the medial rectus muscle measured by anterior segment optical coherence tomography

PURPOSE

We evaluated long-term changes in conjunctival bulge after medial rectus muscle (MR) tightening using the plication method.

STUDY DESIGN

Retrospective and observational.

METHODS

Patients who underwent MR plication for exotropia from December 2016-March 2020 at Okayama University Hospital were included. Thirty two eyes of 27 patients were enrolled. The thickness from the conjunctiva to sclera (TCS) at the limbus and insertion sites were measured using anterior segment optical coherence tomography preoperatively and 1 month, 4 months, and 12 months postoperatively. Correlations between the 1- and 12 month postoperative TCS and amount of MR tightening were analyzed.

RESULTS

Preoperative and 4 month postoperative TCS at the limbus site were not significantly different (P=0.07). The 12 month postoperative TCS at the insertion site was significantly thinner than at 1 month postoperative (P<0.01), although significantly thicker than the preoperative TCS (P<0.01). No significant correlations were found between the amount of MR tightening (in mm) and 1- or 12 month postoperative TCS at the limbus (P=0.62 and P=0.98, respectively) and insertion (P=0.50 and P=0.24, respectively) sites.

CONCLUSION

The TCS at the insertion site peaked at 1 month postoperatively, continued to decrease for longer than 4 months postoperatively, continuing until 12 months postoperatively. The TCS at the insertion site 12 months postoperatively is thicker than preoperatively. The TCS at both the limbus and insertion sites was not related to the amount of medial rectus muscle tightening.

Medial Rectus Muscle Resection Versus Plication: A Comparison of Conjunctival-Scleral Thickness Measured by AS-OCT

PURPOSE

To compare conjunctival-scleral thickness measured with anterior segment optical coherence tomography before and after medial rectus muscle resection and plication for exotropia.

METHODS

In this prospective observational study, patients with exotropia aged 5 years and older who underwent medial rectus muscle resection or plication through limbal incision of the conjunctiva between April 2016 and June 2018 were enrolled. Conjunctivalscleral thickness was measured with anterior segment optical coherence tomography before and 3 and 6 months after surgery at 1.5 mm (limbus), 4 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur. One examiner made measurements twice blinded for the initial data. Conjunctival-scleral thickness was compared between groups using the Mann-Whitney U test.

RESULTS

Twenty participants were divided into two groups: resection (n = 11) and plication (n = 9). The respective conjunctival-scleral thicknesses before and 3 and 6 months after surgery in the resection group were as follows: 0.76, 0.90, and 0.86 mm at the limbus; 0.86, 1.18, and 1.12 mm at the insertion; and 1.04, 1.41, and 1.33 mm at the tendon. Corresponding values in the plication group were as follows: 0.74, 0.87, and 0.81 mm at the limbus; 0.84, 1.16, and 1.08 mm at the insertion; and 1.00, 1.39, and 1.27 mm at the tendon. No between-group differences were observed at any location or time.

CONCLUSIONS

No differences in conjunctival-scleral thickness were observed between the resection and plication groups before surgery or at 3 months and 6 months postoperatively. [J Pediatr Ophthalmol Strabismus. 2022;59(4):274-278.].

Interventions for intermittent exotropia

BACKGROUND

The clinical management of intermittent exotropia (X(T)) has been discussed extensively in the literature, yet there remains a lack of clarity regarding indications for intervention, the most effective form of treatment, and whether there is an optimal time in the evolution of the disease at which any given treatment should be carried out.

OBJECTIVES

The objective of this review was to analyze the effects of various surgical and non-surgical treatments in randomized controlled trials (RCTs) of participants with intermittent exotropia, and to report intervention criteria and determine whether the treatment effect varies by age and subtype of X(T).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 1), which contains the Cochrane Eyes and Vision Trials Register; Ovid MEDLINE; Ovid Embase; Latin American and Caribbean Health Science Information database (LILACS); the ISRCTN registry; ClinicalTrials.gov, and the WHO ICTRP. The date of the search was 20 January 2021. We performed manual searches of the British Orthoptic Journal up to 2002, and the proceedings of the European Strabismological Association (ESA), International Strabismological Association (ISA), and American Association for Pediatric Ophthalmology and Strabismus meeting (AAPOS) up to 2001.

SELECTION CRITERIA

We included RCTs of any surgical or non-surgical treatment for intermittent exotropia.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.

MAIN RESULTS

We included six RCTs, four of which took place in the United States, and the remaining two in Asia (Turkey, India). A total of 890 participants with basic or distance X(T) were included, most of whom were children aged 12 months to 10 years. Three of these six studies were from the 2013 version of this review. Overall, the included studies had a high risk of performance bias as masking of participants and personnel administering treatment was not possible. Two RCTs compared bilateral lateral rectus recession versus unilateral lateral rectus recession with medial rectus resection, but only one RCT (n = 197) reported on the primary outcomes of this review. Bilateral lateral rectus recession likely results in little difference in motor alignment at near (MD 1.00, 95% CI -2.69 to 4.69) and distance (MD 2.00, 95% CI -1.22 to 5.22) fixation as measured in pupillary distance using PACT (moderate-certainty evidence). Bilateral lateral rectus recession may result in little to no difference in stereoacuity at near fixation (risk ratio (RR) 0.77, 95% CI 0.35 to 1.71), adverse events (RR 7.36, 95% CI 0.39 to 140.65), or quality of life measures (low-certainty evidence). We conducted a meta-analysis of two RCTs comparing patching (n = 249) with active observation (n = 252), but were unable to conduct further meta-analyses due to the clinical and methodological heterogeneity in the remaining trials. We found evidence that patching was clinically more effective than active observation in improving motor alignment at near (mean difference (MD) -2.23, 95% confidence interval (CI) -4.02 to -0.44) and distance (MD -2.00, 95% CI -3.40 to -0.61) fixation as measured by prism and alternate cover test (PACT) at six months (high-certainty evidence). The evidence suggests that patching results in little to no difference in stereoacuity at near fixation (MD 0.00, 95% CI -0.07 to 0.07) (low-certainty evidence). Stereoacuity at distance, motor fusion test, and quality of life measures were not reported. Adverse events were also not reported, but study authors explained that they were not anticipated due to the non-surgical nature of patching. One RCT (n = 38) compared prism adaptation test with eye muscle surgery versus eye muscle surgery alone. No review outcomes were reported. One RCT (n = 60) compared lateral rectus recession and medial rectus plication versus lateral rectus recession and medial rectus resection. Lateral rectus recession and medial rectus plication may not improve motor alignment at distance (MD 0.66, 95% CI -1.06 to 2.38) (low-certainty evidence). The evidence for the effect of lateral rectus recession and medial rectus plication on motor fusion test performance is very uncertain (RR 0.92, 95% CI 0.48 to 1.74) (very low-certainty evidence).

AUTHORS' CONCLUSIONS

Patching confers a clinical benefit in children aged 12 months to 10 years of age with basic- or distance-type X(T) compared with active observation. There is insufficient evidence to determine whether interventions such as bilateral lateral rectus recession versus unilateral lateral rectus recession with medial rectus resection; lateral rectus recession and medial rectus plication versus lateral rectus recession and medial rectus resection; and prism adaptation test prior to eye muscle surgery versus eye muscle surgery alone may confer any benefit.

Lateral rectus resection versus lateral rectus plication in patients with residual Esotropia

This study was aimed to compare the surgical outcomes of lateral rectus plication and resection techniques on patients with residual esotropia. In this randomized clinical trial, a total of 57 patients with residual esotropia (31 females) who were candidates for lateral rectus resection were randomized into plication (n = 27) and resection (n = 30) groups. The inclusion criteria were residual Esotropia after uni- or bilateral medial rectus recession. Subjects with a history of prematurity, lack of central fixation, extraocular muscle palsy, systemic, ocular disorders, history of lateral rectus operation, or follow up less than 3 months were excluded. Ophthalmic examinations were conducted preoperatively and at 1, 3-, and 6-month follow-ups. Surgical success rate was considered postoperative eso- or exotropia ≤10 pd. Based on the study results, there was no statistically significant difference between the two groups regarding the pre- (plication: 27.9 ± 9.8 pd and resection: 26.4 ± 7.6 pd; P = .52) and postoperative mean angle of deviation at far distance in month 3 (plication: 5.1 ± 7.1 pd and resection: 5.4 ± 3.2 pd; P = .82). Postoperative success rate also showed similarity between these two groups at all postoperative follow-ups of months 1, 3, and 6.There was no statistically significant difference between dose responses of these groups in uni- or bilateral operations. In conclusion, lateral rectus plication and resection showed statistically similar results. Each surgical method could be selected according to surgeon's skill and comfort. We recommend plication method for patients with postoperative probability of anterior segment ischemia.

Comparison of medial rectus resection and plication in exotropic patients

PURPOSE

To compare the surgical outcomes of the plication technique with the resection method to treat exotropic patients.

METHODS

In this prospective randomized clinical trial, a total of 52 exotropic patients (27 females and 25 males) who were candidates for medial rectus resection were randomly classified into the plication (n = 24) and resection (n = 28) groups. Comprehensive ophthalmic examination included cyclorefraction, assessment of the best corrected visual acuity (BCVA), evaluation of the extraocular muscle, ocular deviation measurement and stereopsis measured using a Titmus test. Ocular anterior and posterior segments were examined using slit-lamp and indirect ophthalmoscopy. Patients were randomly divided to medial rectus plication and medial rectus resection groups. The plication technique was the same as for resection, but in the last step the muscle was folded. Examinations were repeated at the 1- and 3-day as well as 1-, 2-, 3- and 6-month follow-ups. If the postoperative ocular deviation was in the range of 5 PD esotropia to 10 PD exotropia, it was considered a successful surgical outcome.

RESULTS

Results show that there was no statistically significant difference between the two groups regarding near and far deviations (P_N = 0.298, P_F = 0.103), surgical dose response (P = 0.904) and postoperative success rate (plication, 87% and resection, 89.3%, P > 0.99). Reoperation was needed in 13% and 10.7% of the plication and resection groups, respectively (P > 0.05).

CONCLUSIONS

Medial rectus plication is an effective and appropriate alternative option for medial rectus resection in exotropic patients.

Surgical outcomes of plication versus resection in basic type of intermittent exotropia

OBJECTIVES

To compare the surgical outcomes of plication versus resection in basic type of intermittent exotropia.

DESIGN

Prospective interventional study.

PARTICIPANTS

60 patients above 6 years of age with diagnosis of basic type of intermittent exotropia.

METHODS

A randomized study was conducted in 60 patients above 6 years of age with diagnosis of basic type of intermittent exotropia. They were equally divided in two groups by computer generated random number table. Group A underwent recession and plication (RP) and group B underwent recession and resection (RR) based on post patch deviation with constant 8 mm lateral rectus recession in both groups. Parameters assessed were postoperative alignment, cosmetic outcome, improvement in binocularity & stereoacuity and dose effect. Successful outcome was defined as post patch deviation ≤ 10 Prism diopters (PD) of exophoria/exotropia to < 5 PD of esophoria/esotropia at 12 months follow up.

RESULTS

The mean preoperative and postoperative deviation was 44.67 ± 4.5 PD and 10.13 ± 3.6 PD respectively in group A and 43.17 ± 4.8 PD and 9.40 ± 3.3 PD respectively in group B (p = 0.423). The exodrift at 12 months follow up was 4.4 ± 2.8 PD in group A and 4.67 ± 3.29 PD in group B. There was statistically no significant difference in outcomes between the two groups. Mean effect of MR plication at last follow up was 5.91 PD/mm and MR resection was 5.5 PD/mm (p = 0.877).

CONCLUSION

Both procedures achieved acceptable ocular alignment and had a comparable dose effect. Plication has certain added advantages over resection hence may be preferred as an alternate tightening procedure.

Comparison of bilateral medial rectus plication and resection for the treatment of convergence insufficiency-type intermittent exotropia

PURPOSE

To compare the clinical outcomes of bilateral medial rectus plication and resection for the treatment of convergence insufficiency (CI)-type intermittent exotropia (IXT).

METHODS

Fifty-five patients with CI-type IXT were included in this prospective study and were followed for 6 months. The patients were randomized into two groups: the bilateral medial rectus plication (BMRP) group (n = 27) and the bilateral medial rectus resection (BMRR) group (n = 28). The eye examinations of each patient were carried out before the surgery and at 1 day and 1, 3 and 6 months postoperatively. The success rate, angle of deviation, stereoacuity, operative time and postoperative conjunctival swelling and redness score were analysed.

RESULTS

The mean deviation at distance at 1 day postoperatively was +6.6 ± 5.6 prism dioptres (PD) in the BMRP group, which was lower than the value of +10.8 ± 9.3 PD observed in the BMRR group (p = 0.046). There was more overcorrection in the BMRR group at first day after surgery. However, there were no significant differences in deviations or success rates were observed between the two groups at 1, 3 and 6 months after surgery (p > 0.05). The operative time in the BMRP (12.9 ± 1.4 min) group was shorter than that in the BMRR (14.7 ± 1.4 min) group (p < 0.001). Postoperative conjunctival swelling and redness were milder in the BMRP group than in the BMRR group (p < 0.001).

CONCLUSION

The BMRP surgery could be an alternative procedure to BMRR for the treatment of CI-type IXT with less immediate postoperative overcorrection and simpler, safer, less traumatic characteristics.