Recurrent Strabismus Research Articles

Heavy eye syndrome as a cause of recurrent strabismus

This is the case of a 69-year-old female with strabismus. She had a corrective surgery; however, 20 years later, progressive esotropia and hypotropia occurred. Magnetic resonance imaging (MRI) of the orbits showed increased dislocation angles of the bilateral lateral recti (LR) and superior recti (SR). Both LR-SR bands were not clearly appreciated. Other findings are staphyloma and irregular borders of the medial recti. MRI findings are suggestive of heavy eye syndrome.

Призматическая коррекция остаточного или рецидивирующего косоглазия

Introduction. Recurrent strabismus is a common issue after operations because of heterotrophy. Many scientific works have examined clinical parameters that may predispose to relapse of esotropia after surgery, including poor sensory status, high ratio of accommodative convergence to accommodation, uncorrected farsightedness or combination of these factors. Purpose. To evaluate the effectiveness of prismatic correction of recurrent esotropia in patients after the first stage of surgical treatment. Material and methods. The study group included 24 patients. They were divided into two groups in depends on the postoperative functional treatment. 1st group consisted of 12 patients with partially accommodative esotropia aged 5 to 8 years (6,48 ± 1,12 years) with average hypermetropic refraction +3,10 ± 0,54 diopters. This group of patients was assigned prismatic correction after a relapse of esotropia. 2st group consisted of 12 patients with partially accommodative esotropia aged 5 to 8 years (6,22 ± 1,29 years) with average hypermetropic refraction +3,13 ± 0,61 diopters. This group of patients was assigned orthoptic treatment after a relapse of esotropia. Results. Prismatic correction contributed to recovery binocular vision at 75 % of patients with recurrent esotropia ≤ 20 PD, in the comparison group (orthoptic treatment) – at 50 %. Moreover, the number of patients with stereopsis in the group «EFP» after the treatment was higher than in the group «Synoptophore» (p < 0,05). Conclusion. Prismatic correction ensures optimal motor status while maintaining sufficient sensory balance in most patients with recurrent esotropia after performing recession rectus medialis in combination with median duplication m. rectus lateralis. Keywords: Recurrent strabismus, binocular vision, elastic Frensel prism

Management of stretched scar\u2013 induced secondary strabismus

BackgroundTo determine characteristics and management of consecutive or recurrent strabismus secondary to stretched scar.MethodsThis is a retrospective review of all patients diagnosed with late secondary consecutive or recurrent strabismus due to stretched scar from 2012 to 2017. The diagnosis of stretched scar was made in any case of late (≥ 1 month) consecutive or recurrent strabismus associated with underaction of the previously operated muscle. The diagnosis was confirmed intraoperatively by negative forced duction test and the characteristic appearance of the scar tissue. Surgical correction involved excision of the scar tissue with muscle re-attachment to the sclera using non-absorbable sutures. Study parameters include improvement in secondary deviations, degree of muscle underaction and diplopia.Results21 consecutive and 6 recurrent cases of stretched scar –induced strabismus were identified and all cases were associated with variable degrees of limited ocular duction. After surgical correction of the stretched scar, consecutive deviations in the form of consecutive esotropia and exotropia were corrected by means of 26.1PD and 65.6PD while recurrent deviations in the form recurrent exotropia and recurrent hypertropia were corrected by means of 34.3PD and 11PD respectively with significant improvement of limited ocular ductions. 21 patients had diplopia at presentation and all were improved after surgery.Conclusionmanagement of stretched scar –induced secondary strabismus by excision of the stretched scar and muscle fixation to the sclera using non-absorbable sutures significantly corrects secondary deviations and improves limitation of ocular duction.

Evalution of life quality of children with intermittent exotropia one year after the effective surgical treatment

Objective: To investigate the changes of life quality in children with intermittent exotropia (IXT) and their parents 1 year after surgical treatment. Methods: Retrospective study. The scores of Chinese version of the intermittent exotropia questionnaire (CIXTQ) and follow-up visits at 1 week preoperatively and 3 months, 12 months postoperatively were collected from 122 IXT children with successful eye positions 3 months postoperatively and their parents in Department of Ophthalmology, the First Affiliated Hospital of Nanjing Medical University from December 2015 to July 2016. The CIXTQ scores of children with different eye positions 1 year postoperatively, the impact of parent CIXTQ scores and 1-year postoperative eye positions on children's CIXTQ scores and parents' proxy CIXTQ scores, were analyzed. Repeated measures anova was used for the analysis. Results: A total of 122 IXT children were collected in this study, there were 64 boys and 58 girls, age (2-15) years, mean (7±3) year. The eye positions of 88 (72.1%) children were successful 1 year postoperatively, and 34 (27.9%) were undercorrected 1 year postoperatively. The CIXTQ scores of children with different eye positions 1 year postoperatively were significantly higher than that at 1 week preoperatively and at 3 months postoperatively(scores of all children, 83.27±9.49 vs. 57.30±8.37 and 69.19±7.95; successful children, 84.12±8.80 vs. 57.36±8.16 and 69.99±7.85; undercorrected children, 81.07±10.95 vs. 57.14±9.04 and 67.10±7.98), with statistical significance (compared with 1 week preoperatively, t=22.44, 22.13, 8.73; compared with 3 months postoperatively, t=12.42, 11.40, 5.49; all P<0.001). However, the parent' CIXTQ scores of children with recurrent strabismus showed no significant differences when compared to those at 3 months postoperatively (P>0.05). The CIXTQ scores of parents and eye positions 1 year postoperatively showed no impact on children's CIXTQ and parents' proxy CIXTQ scores (all P>0.05). Conclusion: The orthodontic surgery can effectively improve the life quality of children with IXT and their parents 1 year after surgical treatment, and there is no correlation between the life quality of children and their parents. (Chin J Ophthalmol, 2019, 55:31-36).

The Impact of Strabismus Surgery on Irish Adults.

Aims:Our primary objective was to evaluate our adult strabismus service and the impact strabismus surgery has on quality of life (QOL) in patients from an Irish cohort. Our secondary objective was to compare QOL outcomes across different subgroups.Methods:A service evaluation was prospectively performed over an 18-month period. We prospectively audited the preoperative and postoperative QOL scores from 35 adult strabismus procedures using the adult strabismus score (AS-20) (0–100).Results:Postoperative patients achieved an average 14.22 score increase in QOL (p = 0.0018). Females showed lower preoperative scores (46.78 vs. 60.89; p = 0.047) and a trend towards larger increases compared to males (21.05 vs. 51.12; p = 0.1). No significant difference was detected between primary and recurrent strabismus repairs (18.10 vs. 16.55; p = 0.4). Lower preoperative scores (0–33) were associated with higher increases compared with moderate (34–66) and high (67–100) preoperative scores (33.47, 12.03, –4.57 respectively). Patients reporting QOL score decreases after surgery were more likely to come from the high preoperative score group than the moderate or low groups (50%, 19% and 22% respectively).Conclusion:We demonstrate that strabismus surgery has a significant positive impact on QOL scores in Irish adults. We show that patients with high preoperative QOL scores may have a greater chance of QOL score decreases postoperatively, despite good clinical alignment. We believe greater preoperative discussion around patient expectations in these cases, may improve subjective postoperative results.

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.

Comparison of lateral rectus muscle re-recession versus medial rectus muscle resection for treatment of moderate angle recurrent exotropia

Recurrent strabismus may develop following surgical treatment for exotropia. We compared the outcomes of unilateral lateral rectus muscle re-recession (LRReRc) and medial rectus muscle resection (MRRs) for treatment of this condition.

Does injection into the dominant or nondominant eye affect the outcome of botulinum toxin injection for recurrent strabismus?

Botulinum toxin injections may be used for patients with recurrent strabismus. We hypothesized that injection into the dominant eye would be more effective than injection into the nondominant eye, because there would be a greater stimulus to restore binocularity by inducing temporary misalignment of the preferred eye. Retrospective review of 46 patients with moderate angle recurrent esotropia following previous extraocular muscle surgery. Patients with deprivation amblyopia or developmental delay were excluded. Injection into the dominant eye was usually recommended, but the injection was performed in the nondominant eye if the parents preferred. The pre- and postoperative records were analyzed. Forty-six patients with recurrent esotropia of 14Δ -25Δ were treated with Botulinum toxin. The injection was performed in the nondominant eye in 21 patients (average deviation 19.6Δ; average age 4.9 years), and in the dominant eye in 25 patients (average deviation, 18.9Δ; average age, 5.6 years). Follow-up was more than one year in all patients (average, 4.4 years)Treatment was successful in 13/21 (61%) of patients in the nondominant group and 14/25 (56%) of patients in the dominant group. There was no significant difference in the outcome of botulinum toxin injection for recurrent esotropia between patients who received injections in the dominant or nondominant eye. The efficacy of botulinum toxin for recurrent strabismus is not affected by ocular dominance. Therefore, other factors may be considered when deciding which muscle to inject.

One muscle strabismus surgery

To describe recent evidence from the literature regarding one muscle strabismus surgery for small- to moderate-angle horizontal deviations. The use of one muscle surgery for comitant strabismus had been controversial because of concerns that it may result in a significant number of undercorrections and/or produce ocular incomitance. Recent evidence in unilateral lateral rectus recession for exotropia, unilateral medial rectus recession for esotropia, and unilateral rectus resections for undercorrected or recurrent strabismus and convergence or divergence insufficiency suggests that unilateral rectus muscle surgery is a safe, effective and predictable procedure for small- to moderate-angle horizontal deviations. Future prospective, comparative studies with larger samples in unilateral rectus muscle surgery are still needed. Unilateral rectus muscle surgery is a safe, effective and predictable treatment for small- to moderate-angle horizontal deviations. This procedure limits surgery to one eye, leaves other muscles untouched for repeat surgery, and therefore, should be considered as a primary or alternative approach in the treatment of small- to moderate-angle strabismus.

Unilateral rectus resection in the treatment of undercorrected or recurrent strabismus.

When surgery is required for an undercorrection or for a recurrent strabismus that is in the same direction as the previous deviation, traditional options have included a rerecession of the previously operated muscle(s), a marginal myotomy of the previously operated muscle(s) with or without a resection of the direct antagonist, or a bilateral resection of the antagonist muscles. While many surgeons prefer to perform a bilateral resection for these reasons, a unilateral resection would be a useful approach for small to moderate deviations. Data were collected for patients who had undergone a unilateral rectus resection: age, number of prior surgeries, the preoperative deviation, the postoperative deviation at 1 week, 6 weeks, and 6 months, and the amount of surgery performed. An acceptable postoperative result was considered to be any deviation >8 pd. A resection of a single rectus muscle was undergone by 11 3 patients. Complete data were available on 81 of these patients: 60 underwent a unilateral resection of the lateral rectus and 21 underwent a unilateral resection of the medial rectus. Of those patients undergoing a unilateral lateral rectus resection, 90% were acceptably aligned at the 6-month postoperative exam. Among those patients undergoing a medial rectus resection, 95.2% obtained a successful result. A unilateral resection of the medial or lateral rectus is an effective tool in the treatment of undercorrected or recurrent strabismus. It is predictable, stable in the immediate postoperative period, and limits surgery to 1 eye.

Intraoperative sponge 5-flourouracil to reduce postoperative scarring in strabismus surgery

Introduction: To determine whether 5-fluorouracil is effective in reducing scarring after strabismus surgery we used rectus muscle surgery in experimental animals to compare a single intraoperative dose of 5-fluorouracil with mitomycin C and to compare results in similarly treated controls not receiving these antimetabolites. Methods: Muscle resections were performed on eight rabbits (16 eyes). Four eyes had 5-fluorouracil (50 mg/ml), and four eyes received mitomycin C (0.2 mg/ml), each of which was applied during surgery on an ophthalmic sponge for 5 minutes. Eight eyes served as controls. Six weeks after surgery conjunctival vascularity, muscle length-tension curves, muscle disinsertion force, and the histologic degree of scarring were assessed. Results: The mitomycin C-treated eyes clearly had more conjunctival avascularity and a lower disinsertion force. Both treated groups had flatter length-tension curves and less scarring on histologic examination than the control eyes. Conclusions: Antifibroproliferative therapy with intraoperative sponge 5-fluorouracil appears as effective as, and is possibly safer than, mitomycin C. It may be a useful adjunct in recurrent strabismus surgery or in other situations where a risk of excessive postoperative scarring exists.