Outcomes After Superior Rectus Transposition and Medial Rectus Recession Versus Vertical Recti Transposition for Sixth Nerve Palsy

Three-muscle surgery for large-angle esotropia in chronic sixth nerve palsy: comparison of two approaches

AIMS

To report the effect of two three-muscle surgeries, inferior rectus belly transposition plus augmented superior rectus transposition plus medial rectus recession (ISM) and modified vertical rectus belly transposition plus medial rectus recession (VM), in the management of large-angle esotropia in Chinese patients with chronic sixth nerve palsy.

METHODS

Twenty-eight consecutive patients with large-angle esotropia ≥50Δ were prospectively enrolled and underwent either ISM or VM. Main outcomes included preoperative and postoperative deviation in primary position, abduction limitation and complications. Follow-up was at least 6 months.

RESULTS

Of the included patients, 13 underwent ISM and 15 underwent VM. Preoperatively, ISM group displayed larger esotropia and more severe abduction limitation. 27 patients completed the follow-up. The postoperative horizontal deviation and abduction limitation were similar in both groups. At the last follow-up, ISM group demonstrated greater improvement of abduction limitation than VM group in both grading (group difference -2.1, p<0.001) and quantitation (group difference 2.6 mm, p=0.001). However, eight (30%) patients revealed an induced adduction limitation ≤-1. Of the 22 patients with unilateral palsy, more esotropia of 14.8Δ was corrected in ISM group, compared with VM group (p=0.003). Three patients (14%) developed vertical diplopia and three (14%) developed torsional diplopia. Unexpectedly, keratitis was observed in 4 of 27 (15%) patients, all with concurrent fifth and/or seventh nerve palsy. Three patients aggravated to corneal ulceration.

CONCLUSIONS

Two three-muscle surgeries, ISM and VM were both effective for large-angle esotropia in Chinese patients with chronic sixth nerve palsy. However, attention should be paid to potential complications.

Inferior rectus transposition as a secondary surgery in patients with acquired abducens nerve palsy

We report the outcomes in 2 patients with acquired abducens nerve palsy with residual esotropia following superior rectus transposition and medial rectus recession who subsequently underwent inferior rectus transposition as a second procedure. Both patients showed improved abduction and reduced esotropia, with no induced cyclotorsion or vertical deviation. Inferior rectus transposition as a secondary procedure in these 2 patients with abducens nerve palsy appeared to augment the effect of prior superior rectus transposition and medial rectus recession.

Preliminary Results of New Modification of Vertical Muscle Transposition to Enhance Abducting Force in Sixth Nerve Palsy

Introduction

Since 1907, multiple transposition procedures have been established for the treatment of abducens paralysis. The purpose of the study was to determine where the transposed muscle should be reattached in order to increase the tangential force necessary to improve abduction.

Methods

Retrospective case review of 12 consecutive patients with abducens paralysis who underwent transposition procedures between 2016 and 2019 was conducted. Vertical rectus muscles are transposed to the insertion of lateral rectus muscle; the temporal parts are joined and sutured to the sclera on top of the lateral rectus muscle in the middle of the insertion. The nasal parts are sutured to the sclera following the spiral of Tillaux. The muscle junction suture is placed 8 mm from the insertion, with the temporal parts of the vertical muscles bellies joined and sutured to the lateral rectus muscle. A full-tendon transposition was performed on 11 patients, a half-tendon transposition procedure on 1 patient. The minimum follow-up was 3 months.

Results

The mean preoperative deviation was ET of 37° (range: ET 24° to ET 51°). The mean preoperative abduction limitation was 5 mm from midline (range: 7 to 1 mm). The postoperative mean deviation was ET of 2° (range: 0° to ET 5°). The postoperative mean abduction improvement was 5 mm past midline (range: 2-6 mm). There were no complications or signs of anterior segment ischemia.

Conclusion

To achieve the maximal abductive force from the transposed muscles, we suggest that the vertical muscles be reattached as close as possible to the middle of the lateral rectus insertion.

A comparative multicentric long-term study of un-augmented modified Nishida procedure vs augmentation in unilateral sixth nerve palsy

PURPOSE

To compare the effectiveness of three procedures: modified Nishida procedure alone vs modified Nishida procedure combined with medial rectus recession (MRc) vs modified Nishida procedure combined with MRc and botulinum toxin (BT) for severe unilateral sixth nerve palsy.

DESIGN

Consecutive, interventional case series.

METHODS

The medical records of a consecutive series of patients with severe unilateral sixth nerve palsy who underwent modified Nishida procedure in multiple centres were reviewed. Surgical technique was decided preoperatively at the surgeon's discretion. The preoperative and postoperative findings were compared.

RESULTS

Of the 43 patients with abducens palsy that received the procedure, 32 were included (mean age 38.6 ± 19.8 years). Mean preoperative deviation was 63.0 ± 27.3 prism dioptres (PD) and mean limitation of abduction -4.5 ± 1.2. Five patients underwent a modified Nishida procedure alone, 24 patients had an additional MRc and 3 patients were also injected with BT. Overall, the average correction of modified Nishida technique by itself was 29.4 ± 6.6 PD (range 20-36) and adding a MRc corrected 62.6 ± 23.8 PD (range 24-120). Modified Nishida procedure, MRc and BT altogether corrected 95.0 ± 18.0 PD (range 75-110). No postoperative complications were observed in any of the patients.

CONCLUSIONS

Excellent outcomes with fewer complications are obtained with modified Nishida procedure alone. The need for additional procedures such as MRc and BT which increase the effect in primary position can be determined depending on passive duction and preoperative horizontal deviation.

Effect of Modified Vertical Rectus Belly Transposition vs Augmented Superior Rectus Transposition Plus Medial Rectus Recession for Chronic Sixth Nerve Palsy: A Randomized Clinical Trial

Importance

Both vertical rectus belly transposition (VRBT) and superior rectus transposition (SRT) can be performed simultaneously with ipsilateral medial rectus recession (MRc) and have been shown to be effective for chronic sixth nerve palsy. However, it is unclear whether VRBT is superior to SRT in correcting esotropia.

Objective

To compare the effectiveness of modified VRBT plus MRc (mVRBT-MRc) vs augmented SRT plus MRc (aSRT-MRc) in Chinese patients with chronic sixth nerve palsy.

Design, Setting, and Participants

This parallel-design, double-masked, single-center, randomized clinical trial was conducted from January 15, 2018, to May 24, 2021. The follow-up visits were scheduled at 1 month and 6 months. Eligible Chinese participants with unilateral chronic sixth nerve palsy were randomly assigned to receive either mVRBT-MRc (VRBT group) or aSRT-MRc (SRT group).

Interventions

mVRBT-MRc or aSRT-MRc.

Main Outcomes and Measures

Change of horizontal deviation in primary position from baseline to 6 months.

Results

Of the total 25 eligible participants, the mean (SD) age was 45.4 (12.6) years, with 10 male participants (40%) and 15 female participants (60%). Thirteen participants (52%) were randomly assigned to the VRBT group, and 12 (48%) were randomly assigned to the SRT group. At baseline, the mean (SD) horizontal deviation was 65.7 (10.8) prism diopters (Δ) in the VRBT group and 60.5Δ(14.1Δ) in the SRT group. Similar amounts of MRc were performed in both groups. At 6 months, the horizontal deviation changed from baseline by 66.3Δ in the VRBT group and by 51.5Δ in the SRT group. The adjusted group difference was 10.9Δ (95% CI, 5.3Δ-16.6Δ), favoring the VRBT group (P = .001). Four times as many participants corrected more than 60Δ with mVRBT-MRc compared with aSRT-MRc. The group difference of the improvement of abduction limitation was -0.2 (95% CI, -0.8 to 0.5; P = .64). Although there was a higher proportion of undercorrection in the SRT group (difference, 45%; 95% CI, 16%-75%; P = .01), no differences were identified for other suboptimal outcomes between groups.

Conclusions and Relevance

Compared with aSRT-MRc, mVRBT-MRc showed better effect in correcting esotropia with no differences detected for other suboptimal outcomes. mVRBT-MRc may be a promising alternative surgical procedure for chronic sixth nerve palsy, particularly for large esotropia of more than 60Δ, if these results are confirmed in larger, diverse cohorts with longer follow-up.

Trial Registration

ChiCTR Identifier: ChiCTR-INR-17013705.

Supramaximal Horizontal Rectus Recession-Resection Surgery for Complete Unilateral Abducens Nerve Palsy

Purpose

To review the surgical procedures and outcomes of supramaximal horizontal rectus recession–resection surgery for abduction deficiency and esotropia resulting from complete unilateral abducens nerve palsy.

Methods

A total of 36 consecutive cases diagnosed as complete abducens nerve palsy, receiving supramaximal medial rectus recession (8.5 ± 1.4 mm, range: 6–10) combined with a supramaximal lateral rectus resection (11.1 ± 1.7 mm, range: 8–14) as performed over the period from 2017 to 2020, were reviewed retrospectively. All surgeries were performed by a single surgeon. Pre- and post-operative ocular motility, ocular alignment, forced duction test, binocular vision, abnormal head posture, and surgical complications were assessed.

Results

Of these 36 cases, 23 (63.8%) were followed up for greater than 2 months (Mean ± SD = 8.4 ± 6.0, range: 2–24) after surgery and the collected data was presented. Mean ± SD age of these patients was 41.7 ± 14.4 (range: 12–67) years with 73.9% being female. Trauma (52.2%, 12/23) and cerebral lesions (21.7%, 5/23) were the primary etiologies for this condition. Esodeviation in primary position improved from 55.5 ± 27.2 prism diopters (PD) (range: +25 to +123) to 0.04 ± 7.3 PD (range: −18 to +12) as assessed on their last visit. Pre-operative abduction deficits of −5.6 ± 1.0 (range: −8 to −4) reduced to −2.4 ± 1.4 (range: −4 to 0) post-operatively. The mean dose-effect coefficient of 2.80 ± 1.20 PD/mm (range: 1.07–6.05) was positively correlated with pre-operative esodeviation. Rates of overcorrection and ortho were 69.6 and 26.1%, respectively, on the first day after surgery, while on their last visit the respective levels were 4.3 and 82.6%.

Conclusion

Supramaximal horizontal rectus recession–resection surgery is an effective treatment method for complete abduction deficiency. The dose-effect was positively correlated with pre-operative esodeviation. Overcorrection on the first day post-operatively is required for a long-term satisfactory surgical outcome.

Outcomes of half-width vertical rectus transposition augmented with posterior fixation sutures for sixth cranial nerve palsy

AIM

To describe the experience with half-width vertical muscles transposition (VRT) augmented with posterior fixation sutures.

METHODS

The clinical charts of all patients, who underwent half-width VRT augmented with posterior fixation sutures for sixth cranial nerve palsy from January 2003 to December 2018, were retrospectively reviewed. For each patient, pre- and post-operatively, the largest measured angle was used for the calculations, usually resulting with the angle for distance, except in young infants, where measurements were made at near fixation using the Krimsky test.

RESULTS

Fifteen patients met the inclusion criteria for the study, of them 9 (60.0%) had also medial rectus muscle recession at the time of surgery. Mean follow-up period was 21.4±23.2mo (range 1.5-82mo). Preoperative mean esotropia was 51.3±19.7 prism diopter (PD; range 20-90 PD). Postoperative mean deviation on final follow-up was 7.7±20.2 PD (range -40 to 35 PD; P=0.018). In all patients with preoperative abnormal head position, improvement was noted. Ten (66.7%) patients had improvement in abduction and 10 (66.7%) patients reported improvement in their diplopia, by final follow-up. The addition of medial rectus recession was correlated with a larger change in postoperative horizontal deviation compared to baseline (P=0.026). Two (13.3%) patients developed a vertical deviation in the immediate postoperative period which had resolved in one of them.

CONCLUSION

Half-width VRT augmented with posterior fixation suture, with or without medial rectus muscle recession, is an effective and safe procedure for esotropia associated with sixth cranial nerve palsy. A major improvement in the angle of deviation is expected. Most patients will have improvement in their abnormal head position and diplopia.

A Review of Transposition Techniques for Treatment of Complete Abducens Nerve Palsy

Purpose:

To review various types of extraocular muscle transposition procedures for management of strabismus in sixth cranial nerve palsy with little lateral rectus (LR) muscle function, along with their pros and cons.

Methods:

We performed a comprehensive review of transposition procedures in sixth cranial nerve palsy, based on literature published anytime up to March 2021. A thorough search through PubMed and Cochrane databases was performed. All types of clinical studies on different transposition procedures in LR palsy, were included.

Results:

Eighty-six original articles in English, with full text or abstracts available, were included in the review, among which 16 are prospective studies, 48 retrospective, 3 review articles, 1 randomized clinical trial, 17 case reports, and 1 letter. Vertical rectus transposition has demonstrated promising results, especially in abduction improvement and expansion of binocular diplopia-free visual field, albeit the possible adverse effects such as anterior segment ischemia, especially in the presence of medial rectus contracture, and induced vertical deviation may become troublesome. Partial muscle transposition, single muscle transposition, and also transposition without tenotomy have all been introduced to reduce the risk of multiple muscle manipulation and ischemia. On the other hand, different adjustable transpositions are being utilized to manage concomitant or induced vertical deviations.

Conclusion:

Transposition procedures are highly effective in the treatment of esotropia caused by complete LR palsy. Various techniques for vertical muscle transposition have been proposed, with each of them having certain advantages and disadvantages.

Strabismus Surgery Outcomes and Their Determinants in Patients with Chronic Sixth Nerve Palsy

PURPOSE

Patients with chronic sixth nerve palsy (CSNP) comprise a heterogeneous population, and the optimal surgical solution remains uncertain. Here, we present the success rate and factors associated with the success of strabismus surgeries for CSNP.

METHODS

This was a retrospective cohort study of patients with strabismus due to CSNP operated on between 2015 and 2019 in a tertiary eye hospital in central Saudi Arabia. Surgical success was defined as a horizontal deviation of ≤10 prism diopters (PDs) assessed at least 12 months after surgery. Differences between groups with respect to the primary outcome were assessed.

RESULTS

Fifty-five patients were analyzed with a median follow-up of 24 (range 12-48) months. Superior rectus and inferior rectus transposition (34.5%) and medial rectus recession with lateral rectus resection (32.7%) were the main surgeries performed. The overall success rate was 67.3% (95% confidence interval 54.9-79.7). Bilateral CSNP (P = 0.05), a higher preoperative angle of deviation (P = 0.002), or a greater degree of preoperative limitation of abduction (P = 0.012), but not the type of surgery (P = 0.09), were more likely to result in an under-corrected outcome of >10 PD. The preoperative deviation angle showed a trend toward being associated with a poor outcome after surgery (P = 0.06). Six patients with high-angle deviation before surgery required second surgery.

CONCLUSION

While the surgical procedure does not impact outcomes, the severity of preoperative horizontal deviation might impact surgical success and the need for reoperation. Patients with severe CSNP should be counseled appropriately about the chances of surgical success and the potential need for further interventions.

Risk of torsion in superior rectus transposition surgery augmented with posterior scleral fixation sutures

It has been reported that superior rectus transposition combined with medial rectus recession can provide as good results as transposition of both vertical rectus muscles, with no adverse effects on torsion or postoperative vertical misalignment. Further augmentation of transposition surgery can be achieved through the use of posterior fixation sutures, myopexy and botulinum toxin into the medial rectus. We report a patient with complete bilateral traumatic sixth cranial nerve palsies who underwent sequential superior rectus transposition surgery combined with medial rectus recession. The surgery was augmented with a myopexy (posterior suture joining superior and lateral recti with no scleral fixation) in the first eye and with a posterior fixation suture (with scleral fixation) in the second eye. After the second procedure, despite a significant improvement in horizontal alignment, the patient developed 15 degrees of incyclotorsion which was attributed to the scleral fixation suture. The patient underwent removal of the scleral suture and 3 months postoperatively had a significant reduction in incyclotorsion to 8 degrees; however this continued to be a barrier to fusion. Vertical rectus transposition of superior and inferior recti augmented with posterior scleral fixation sutures is one type of conventional surgery for complete lateral rectus palsy. In more recent times, it has become common to transpose the superior rectus alone along with recession of the contracted medial rectus. This procedure can also be augmented with a posterior fixation suture which may or may not be attached to the sclera. Whilst this surgery has gained popularity it is not without risk as demonstrated by our case in which transposition of the superior rectus was associated with postoperative incyclotorsion. In this case a possible explanation may be the use of a the posterior scleral fixation suture as it did not occur when no scleral fixation was used. Furthermore, removal of the posterior scleral fixation suture did reduce the torsion significantly although it did not eliminate it.

[Nishida Extraocular Muscle Transposition Surgery for Abducens Nerve Palsy]

BACKGROUND

Surgical treatment of abducens nerve palsy depends on the remaining function of the lateral rectus muscle. Vertical rectus transposition surgery is indicated if the attempted maximal abduction effort does not rotate the eye beyond the midline. After the first description more than 100 years ago, a variety of muscle transposition modifications have been suggested. Nishida's minimally-invasive adaptation has attracted a great deal of attention in recent years.

PATIENTS AND METHODS

Retrospective case series of four patients with abducens nerve palsy who were treated with Nishida muscle transposition surgery. Patients' characteristics with special emphasis on comparison between pre- and postoperative angle of deviation and ocular motility are reported.

RESULTS

Four patients (2 females, 2 males) were included in this study. Unilateral transposition surgery was performed in a 7-year-old girl and a 37-year-old woman with a left abducens nerve palsy. In a 56-year-old male with a left sixth nerve palsy and in an 82-year-old male with a right sixth nerve palsy the transposition maneuver was combined with a recession of the medial rectus muscle in the same eye. In all patients, ocular motility was improved and the angle of deviation was reduced.

CONCLUSIONS

Transposition of vertical rectus muscles is well established in the surgical treatment of abducens nerve palsy. Nishida's adaptation is a safe, effective and minimally-invasive treatment option. This vessel-sparing technique also allows for equilateral weakening of the medial rectus muscle.

[Outcomes after medial rectus recession and lateral rectus plication for abducens nerve palsy: A retrospective study]

BACKGROUND

Abducens nerve palsy (ANP) is the most common oculomotor palsy. This study aimed to evaluate the efficacy of medial rectus recession with lateral rectus plication in patients with unilateral acquired ANP and to describe the etiologies of this condition.

METHODS

Thirty-one patients were included in this retrospective single-center study conducted between 2000 and 2019 at the university research hospital in Tours. The following data were collected before and after surgery: diplopia, oculomotor deviations, ocular motility, and head posturing.

RESULTS

The mean age was 55.9±18.9 years and the mean postoperative follow-up was 11±4 months. Postoperatively, the patients had significant reduction in diplopia in primary position (P<0.001), in abduction of the affected eye (P<0.001) and in distance and near horizontal deviations (P<0.001). Abduction of the affected eye was significantly improved (P<0.001), but reduction in head posturing was insignificant (P=0.27). The etiologies were as follows: trauma (8 patients, 26%), neoplasm (6 patients, 16%), stroke-related (5 patients, 16%), compressive (5 patients, 16%), undetermined (5 patients, 16%) and inflammatory (2 patients, 6%).

CONCLUSION

Medial rectus recession with lateral rectus plication is an effective procedure in reducing diplopia and ocular deviation in unilateral acquired ANP and may be used as a first-line intervention regardless of the initial ocular motility limitation in abduction. The causes are mainly traumatic but remain undetermined in one case out of six.

Outcomes of modified vertical rectus belly transposition versus augmented superior rectus transposition for chronic abducens nerve palsy

PURPOSE

To compare the surgical outcomes of modified vertical rectus belly transposition (mVRBT) and medial rectus recession (MRc) versus augmented superior rectus transposition (aSRT) and MRc in Chinese patients with chronic abducens nerve palsy.

METHODS

The medical records of patients with chronic abducens nerve palsy who underwent mVRBT/MRc or aSRT/MRc were retrospectively reviewed. Pre- and postoperative deviation in primary position, pre- and postoperative abduction limitation, and complications were recorded. Follow-up was at least 6 months.

RESULTS

A total of 26 patients (mean age, 37.9 ± 19.6 years; 16 males [62%]) were included. Fourteen patients underwent mVRBT/MRc (mVRBT group) and 12 underwent aSRT/MRc (aSRT group). Both groups had similar amounts of recession (t = 0.27; P = 0.79). After surgery, statistically significant changes of abduction limitation and esotropia were observed (both P < 0.05). However, the difference in abduction improvement between groups was not statistically significant (mVRBT vs aSRT, 2.3 ± 0.91 vs 2.3 ± 0.97; t = 0.10, P = 0.92). Of the 19 patients who underwent unilateral surgery, preoperative esotropia was similar in both groups (t = 1.3; P = 0.21), but more esotropia was corrected in the mVRBT group than in the aSRT group (mVRBT vs aSRT, 57.8^Δ ± 14.3^Δ vs 44.6^Δ ± 9.8^Δ; t = 2.1; P = 0.047). There was no symptomatic vertical or torsional deviation.

CONCLUSIONS

In our patient cohort, mVRBT/MRc showed a better effect in correcting esotropia and a similar effect in improving abduction limitation compared with aSRT/MRc.

Augmented superior rectus muscle transposition in management of defective ocular abduction

Background

Superior rectus muscle transposition (SRT) is one of the proposed transposition techniques in the management of defective ocular abduction secondary to chronic sixth nerve palsy and esotropic Duane retraction syndrome (Eso-DRS). The aim of the current study is to report the outcomes of augmented SRT in treatment of Eso-DRS and chronic sixth nerve palsy.

Methods

a retrospective review of medical records of patients with Eso-DRS and complete chronic sixth nerve palsy who were treated by augmented full tendon SRT combined with medial rectus recession (MRc) when intraoperative forced duction test yielded a significant contracture. Effect on primary position esotropia (ET), abnormal head posture (AHP), limitation of ocular ductions as well as complications were reported and analyzed.

Results

a total of 21 patients were identified: 10 patients with 6th nerve palsy and 11 patients with Eso-DRS. In both groups, SRT was combined with ipsilateral MRc in 18 cases. ET, AHP and limited abduction were improved by means of 33.8PD, 26.5°, and 2.6 units in 6th nerve palsy group and by 31.1PD, 28.6°, and 2 units in Eso-DRS group respectively. Surgical success which was defined as within 10 PD of horizontal orthotropia and within 4 PD of vertical orthotropia was achieved in 15 cases (71.4%). Significant induced hypertropia of more than 4 PD was reported in 3 patients (30%) and in 2 patients (18%) in both groups, respectively.

Conclusion

augmented SRT with or without MRc is an effective tool for management of ET, AHP and limited abduction secondary to sixth nerve palsy and Eso-DRS. However, this form of augmented superior rectus muscle transposition could result in high rates of induced vertical deviation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-020-01779-1.

Hummelsheim procedure combined with medial rectus recession in complete sixth nerve palsy and esotropic Duane Retraction Syndrome

PURPOSE

To evaluate the effect of half tendon vertical rectus muscle transposition (HVRT) combined with medial rectus muscle recession (MRrec) in complete sixth nerve palsy (CSNP) and esotropic Duane Retraction Syndrome (eDRS).

METHODS

A retrospective study of patients with unilateral CSNP or eDRS who underwent HVRT combined with medial rectus recession over the course of 18 years. The patients with previous strabismus surgery and follow up less than 3 months were excluded. Overcorrection was defined as any amount of exotropia, and undercorrection was defined as residual esotropia of ⩾10 prism diopter (PD).

RESULTS

A total of 39 patients were enrolled including 22 CSNP and 17 eDRS patients. Esotropia improved from 45.8 ± 22 and 22.5 ± 6.4 PD to 0.8 ± 2.5 and 0.3 ± 1 PD in CSNP group and eDRS group respectively. The angle of face turn improved from 34.3 ± 8.4° and 26.5 ± 9° to 0.6 ± 2.4° and 0.8 ± 1.6° in the CSNP group and eDRS group respectively. Abduction limitation improved from -4.5 ± 0.5 and -4 ± 0 units to -2.9 ± 0.5 and -2.7 ± 0.5 units in CSNP group and eDRS group respectively. No patient developed a new vertical deviation. An overcorrection occurred in one patient of the eDRS group who improved after botulinum toxin injection in the ipsilateral lateral rectus muscle. Undercorrection was seen in two patients.

CONCLUSION

HVRT combined with MRrec is an effective procedure to improve esotropia, face turn, and abduction limitation in CSNP and eDRS.

Incidence of symptomatic vertical and torsional diplopia after superior rectus transposition for esotropic Duane syndrome and abducens nerve palsy

PURPOSE

To report the incidence of symptomatic vertical and torsional diplopia after superior rectus transposition (SRT) for esotropic Duane syndrome and abducens nerve palsy.

METHODS

The medical records of patients with esotropic Duane syndrome or abducens nerve palsy seen at Boston Children's Hospital (2006-2018) and treated with unilateral SRT with or without augmentation was performed. The primary outcome was incidence of postoperative vertical or torsional diplopia in primary position. The secondary outcome was induced vertical deviation in affected side gaze.

RESULTS

A total of 69 patients met inclusion criteria: 32 with abducens nerve palsy and 37 with esotropic Duane syndrome. Vertical alignment changed in both hyper- and hypotropic directions. Median pre- and postoperative vertical deviation in primary gaze was 1.1^Δ (10th-90th percentile, 0^Δ-6^Δ hypertropia) and 0.4^Δ (10th-90th percentile, 6^Δ hypotropia to 8 ^Δ hypertropia), respectively. Postoperative vertical diplopia occurred in 7%, including 4 of 49 treated with loop myopexy (8%), 1 of 13 without augmentation (8%), and 0 of 7 treated with sclera-fixated augmentation. All but one was successfully treated with prism or secondary surgery. Intorsional change predominated, but no patient had torsional diplopia post adjustment. Vertical misalignment in affected side gaze increased from 19% to 45% after SRT (P = 0.01).

CONCLUSIONS

In this largest-to-date review of patients treated with SRT, with or without MR recession, no patient developed persistent torsional diplopia, while 7% developed symptomatic vertical diplopia in primary position, similar to the reported incidence after balanced vertical rectus transposition. Vertical misalignment in affected side gaze increased, however fusion is already limited by unresolved esotropia in this field.

Adjustable graded augmentation of superior rectus transposition for treatment of abducens nerve palsy and Duane syndrome

PURPOSE

To report the results of adjustable graded augmentation of superior rectus transposition, a novel modification of superior rectus transposition (SRT) designed to reduce postoperative vertical or torsional diplopia.

METHODS

The medical records of patients who underwent adjustable graded augmentation of SRT with or without adjustable medial rectus recession (MRc) from February 2017 to December 2019 were reviewed retrospectively. A Mendez ring was used to monitor torsional change after transposition of the superior rectus muscle to the lateral rectus muscle and after sequential placement of 2 or 3 augmentation sutures by superior rectus-lateral rectus loop myopexy. If excessive mechanical intorsion was induced, the responsible augmentation suture was severed intraoperatively. If torsional or vertical diplopia was noted after recovery, the distal-most augmentation suture was cut. Exotropia was managed by severing the distal-most augmentation suture or by medial rectus adjustment.

RESULTS

A total of 8 patients who underwent adjustable graded augmentation of SRT were included (6 using the 3-suture technique): 3 for esotropic Duane syndrome, 2 for abducens nerve palsy, 1 for Moebius syndrome, and 2 for combined trochlear and abducens nerve palsies. Of the 8 patients, 4 had prior strabismus surgery, and 1 patient had previously undergone treatment with botulinum toxin. Severing one augmentation suture in 3 cases resolved vertical (n = 2) or torsional (n = 1) diplopia and consecutive exotropia (n = 2), resulting in excellent alignment and reduction of torticollis to ≤4° in 7 cases. The technique proved insufficient in 1 patient, who had undergone 3 prior strabismus procedures.

CONCLUSIONS

In this study cohort, adjustable graded augmentation of SRT effectively managed the risk of postoperative vertical or torsional diplopia.

Inferior rectus belly transposition for residual esotropia after augmented superior rectus transposition and medial rectus recession in patients with chronic abducens nerve palsy: a case series

We introduce a novel method for managing residual esotropia after vertical muscle transposition, with minimal risk of anterior segment ischemia, and report 3 patients with chronic abducens nerve palsy who underwent inferior rectus belly transposition subsequently or simultaneously after augmented superior rectus transposition and medial rectus recession.

Vertical rectus transposition procedures for lateral rectus palsy: A systematic review

Multiple transposition procedures have been described for management of lateral rectus palsy. However, relative effect and indications of each procedure are unclear. This systematic review was planned to evaluate functional and anatomical outcomes of vertical rectus transposition (VRT) surgery in patients with lateral rectus palsy. We searched databases in English language, namely, MEDLINE, PubMed Central, EMBASE, Google Scholar, Scopus, and Index Copernicus without any date restrictions in electronic searches, using the search words 'vertical rectus transposition for lateral rectus palsy," "vertical rectus transposition for abducens palsy," "superior rectus transposition," "inferior rectus transposition," and "Hummelsheim procedure." References of the selected publications were also searched to find any relevant studies. We searched for studies that provided data on single VRT and double VRT surgeries for lateral rectus palsies. Three authors independently assessed the related studies gathered from electronic and manual searches. We found 27 studies which were relevant to the review question. As there were no randomized control trials (RCTs) available related to our study question, nonrandomized studies were used to arrive at summarization of outcomes of different transposition procedures. There is a need for prospective RCTs to investigate the different types of transposition procedures for lateral rectus palsy.

Postoperative Correction and Drift After Vertical Rectus Muscle Transposition for Total Sixth Cranial Nerve Palsy

PURPOSE

To determine the magnitude of change between the preoperative and postoperative alignment and amount of postoperative drift for two vertical rectus muscle transpositions (VRTs).

METHODS

Retrospective review of medical records of patients with total sixth cranial nerve palsy who underwent VRT procedures. The primary outcome measure was the magnitude of esotropia in prism diopters (PD) at the preoperative and postoperative visits.

RESULTS

Twenty-seven patients were included. Sixteen had full tendon transposition with Foster augmentation (FTT+FA) and 11 had partial tendon transposition with resection and simultaneous medial rectus recession (PTT+R+MRR). A larger correction was obtained with PTT+R+MRR (mean ± standard deviation [SD]: 52 ± 19 PD; range: 27 to 87 PD) when compared to FTT+FA (mean: 40 ± 13 PD; range: 15 to 68 PD). At postoperative month 2, a greater esotropic drift was noted in the PTT+R+MRR group (16 PD) than the FTT+FA group (6 PD). Although the difference in the amount of correction was not statistically significant (P = .071), the difference in the amount of drift was statistically significant (P = .009).

CONCLUSIONS

There was a trend toward greater correction with PTT+R+MRR than FTT+ FA, but it was not statistically significant. FTT+FA had significantly less postoperative drift than PTT+R+MRR. The results suggest that a small immediate postoperative overcorrection may be desirable in some VRT procedures. [J Pediatr Ophthalmol Strabismus. 2019;56(4):238-242.].

Long-term outcome of full tendon vertical rectus transposition with Foster suture in unilateral complete sixth cranial nerve palsy

Purpose

To evaluate the success rate and long-term motor and sensory outcomes of the full tendon vertical rectus transposition (VRT) with Foster suture for unilateral complete sixth cranial nerve palsy.

Patients and methods

We reviewed the medical records of patients with unilateral acquired sixth cranial nerve palsy who underwent unilateral full tendon VRT with Foster suture between 2005 and 2016 and had a follow-up of ≥2 years. Data on pre- and postoperative diplopia, face turn, ocular deviation, and limitation of abduction were collected. A successful outcome was defined as a horizontal deviation ≤10 prism diopter (PD) of ortho in a primary position at distance and absence of diplopia.

Results

A total of 20 patients were included in this study. Median (IQR) preoperative deviation was esotropia 65 (40–130) PD, which improved to 10 (−4 to 45) PD postoperatively. Median (IQR) improvement of esotropia was 54 (30–76) PD (P<0.001). Median (IQR) preoperative limitation of abduction was −15° (−22.5° to 10°; negative value means before reaching midline), which improved to 15° (7.5°–45°) pass midline postoperatively. Median (IQR) improvement of abduction deficit was 26° (15°–35°) (P<0.001). Successful surgical outcomes were obtained in eleven patients (55%). All patients in the non-successful group (n=9, 45%) had residual esotropia. Two of them underwent additional bilateral medial rectus recession. No postoperative vertical deviation or torsional diplopia was observed.

Conclusion

In our series, the full tendon VRT with Foster suture in unilateral complete sixth cranial nerve palsy resulted in significant improvement of the ocular alignment and range of abduction over the 2-year follow-up period.

Transposition procedures in Duane retraction syndrome

Duane retraction syndrome, or Duane syndrome (DS), is one of several congenital cranial dysinnervation disorders. Patients present with limited horizontal eye movement(s) and globe retraction with eyelid fissure narrowing on attempted adduction due to co-contraction of the lateral and medial rectus muscles in one or both eyes. Various surgical approaches have been proposed to improve binocular alignment, reduce head turn, and minimize undesirable up- or downshoots in DS. Transposition procedures are one such approach, and a number of techniques have been described. These may involve one or both vertical rectus muscles and may or may not include full or partial disinsertion of the rectus muscle(s) from the insertion. Options involving both vertical rectus muscles include full vertical rectus transposition (VRT), partial VRT, rectus muscle union, and other modifications to be discussed. Options involving one vertical rectus muscle include superior rectus transposition (SRT) and inferior rectus transposition (IRT). The effectiveness of any transposition procedure may be enhanced with augmentation (posterior fixation) sutures, resection of the transposed muscle(s), and/or simultaneous weakening of the ipsilateral medial rectus muscle. This review discusses the indications, strengths, weaknesses, and other considerations of these approaches within the context of DS. Since the majority of DS cases are unilateral and most have the esotropic form, this will be the main focus of the review, although other forms will also be discussed.

Anomalous Vertical Deviations in Attempted Abduction Occur in the Majority of Patients With Esotropic Duane Syndrome

PURPOSE

To describe a phenomenon, depression in attempted abduction, not previously recognized as a feature of Duane syndrome (DS).

DESIGN

Retrospective, observational case series.

METHODS

Setting: Institutional practice.

PATIENT POPULATION

Patients diagnosed with esotropic DS at Boston Children's Hospital from 2002 to 2015. Patients with clinical photographs documenting horizontal gaze were included. Patients with prior strabismus surgery were excluded.

OBSERVATION PROCEDURES

Patients were classified into 3 groups according to their vertical eye position in attempted abduction: midline group, depression group, and elevation group. Group assignment was performed by 3 independent ophthalmologists. Baseline characteristics, eye movement, and ocular deviation were compared among the 3 groups.

MAIN OUTCOME MEASURES

Horizontal and vertical deviation on attempted abduction in the DS eye.

RESULTS

Depression in attempted abduction was present in 74 of 113 unilateral patients (66%) and 18 of 42 gradable eyes (43%) of bilateral patients. Abduction limitation was significantly less severe in the midline group (median: -3.0) than in the depression group (median: -4.0) (P = .01). Vertical deviation in attempted abduction was more severe in the elevation group than in the depression group (P = .003).

CONCLUSIONS

Depression of the eye in attempted abduction has not been widely described, yet it is present in the majority of DS patients. It is more likely to occur with more severe abduction limitation. This phenomenon is likely another form of dysinnervation in DS, the result either of anomalous vertical rectus muscle activation or asymmetric lateral rectus muscle innervation during attempted abduction. Awareness of vertical deviation in attempted abduction may facilitate surgical planning in affected patients.

A Modified Surgical Technique to Treat Strabismus in Complete Sixth Nerve Palsy

Introduction

A lot of different techniques have been proposed in order to manage abduction limitation secondary to sixth nerve palsy; however, anterior segment ischemia remains a concern. The aim of this study was to evaluate the results of augmented vertical recti muscle transposition (VRT) with partial recession of medial rectus muscle (MR) for complete, chronic sixth nerve palsy, a new modified technique that could also minimize the risk for anterior segment ischemia (ASI).

Methods

In this nonrandomized 8-year (2009–2017) retrospective review, 20 patients with complete sixth nerve palsy and contracted MR were enrolled. All of them underwent augmented VRT and partial recession of the MR, following a new proposed surgical technique. Only the central part of the MR tendon and belly was recessed by 6.5 mm, leaving 1.5 mm of the upper pole and 1.5 mm of the lower pole of the muscle intact, preserving the circulation of two anterior ciliary arteries.

Results

Twenty patients with a mean age of 43 years (range 12–71), all unilateral cases, were enrolled in this study. The mean preoperative deviation was 64.25 ± 10.9 prism diopters (PD) base out (range 50 to 90). In 17 cases (88%), the postoperative deviation was within 10 PD of orthotropia. Two patients (10%) had residual esotropia (15 PD and 20 PD, respectively), and one patient (5%) had 10 PD of hypotropia. The mean preoperative abduction limitation of −5.9 improved to −3.1 (p < 0.0001). None of the cases presented with ASI (success rate 100%).

Conclusion

Partial recession of the MR preserving the two anterior ciliary arteries (Kozeis modified technique) with augmented vertical recti muscle transposition is an effective procedure, with a high success rate and is probably less risky for ASI.

Surgical outcome of superior rectus transposition in esotropic Duane syndrome and abducens nerve palsy

PURPOSE

To evaluate surgical outcome of superior rectus transposition (SRT) in esotropic Duane syndrome (DS) and abducens nerve palsy.

METHODS

Retrospective medical record analysis of all patients with esotropic DS and abducens nerve palsy treated with SRT at our center with minimum follow-up of 6 months. Primary outcome measures were esotropia in primary position and abduction limitation. Secondary outcome measures included head turn, stereopsis, and cyclovertical deviations.

RESULTS

A total of 20 eyes of 19 patients were included: 9 with DS and 10 with traumatic abducens nerve palsy. One patient had bilateral esotropic DS. Mean age of DS patients was 12.5 ± 10.1 years; of abducens nerve palsy patients, 25.4 ± 11.3 years. Medial rectus recession (MRc) of 3.5 mm was additionally performed in 5 DS eyes. An adjustable MRc 5.6 ± 2.2 mm with or without augmentation suture was performed in all abducens nerve palsy patients. In DS patients, esotropia improved from 27.5^Δ ± 5.4^Δ to 3.6^Δ ± 6.4^Δ (P < 0.001), abduction limitation reduced from -3.8 to -1.8 (P < 0.001), and head posture improved from 20° to 4° (P < 0.001) at 6 months. In abducens nerve palsy patients, esotropia improved from 51.5^Δ ± 18.8^Δ to 6.1^Δ ± 10.7^Δ (P < 0.001), abduction limitation reduced from -3.8 to -2, and head posture improved from 25° to 8° (P < 0.001). Stereopsis improved in 4 patients (P = 0.12). No patient had vertical deviation or torsional diplopia.

CONCLUSIONS

In our patient cohort with esotropic DS or abducens nerve palsy, SRT reduced esotropia and improved abduction. Because of a long-term exotropic drift, initial undercorrection in the immediate postoperative period may prevent eventual overcorrection.

Bilateral superior rectus transposition and medial rectus recession for bilateral sixth nerve palsy

Purpose

To present the results of bilateral superior rectus transposition with medial rectus recession in a case of chronic bilateral sixth nerve palsy.

Observation

Bilateral superior rectus transposition with medial rectus recession resulted in full correction of esotropia with resolution of horizontal diplopia, improvement in abduction, and regain of stereoacuity in our case. There was minimal limitation of adduction, with no abnormal vertical or torsional changes.

Conclusion and importance

Bilateral superior rectus transposition with medial rectus recession appears to be a useful procedure for surgical treatment of bilateral sixth nerve palsy with minimal side effects. Given its potential for reduced risk of anterior segment ischemia (ASI), it may have especially good value in the select group of patients at risk for ASI. Studies with larger sample size and longer follow up are needed to further evaluate this procedure and elucidate the variables in surgical technique for superior rectus transposition.

Augmented superior rectus transposition procedure in Duane retraction syndrome compared with sixth nerve palsy

PURPOSE

Superior rectus transposition (SRT) with medial rectus recession has been used for the treatment of sixth nerve palsy and esotropic Duane retraction syndrome (DRS). The purpose of this study was to compare the results of augmented SRT (with scleral fixation) without medial rectus recession in DRS and sixth nerve palsy.

METHODS

Patients with unilateral esotropic DRS (DRS group) and sixth nerve palsy were included in this prospective, comparative study and underwent SRT. Preoperative forced duction testing was negative or slightly positive in both groups. Prospective measurements were compared between the two groups.

RESULTS

There were 11 patients in the DRS group and 11 patients in the sixth nerve palsy group. The mean preoperative esotropia decreased from 20.9 ± 6.0 prism diopter (PD) at far to 13.2 ± 5.8 PD in the DRS group (P = 0.003). The same measurement improved from 28.0 ± 8.5 PD to 8.4 ± 7.3 PD in the sixth nerve palsy group (P = 0.003). In the sixth nerve palsy group, the improvement in primary gaze esotropia and abnormal head posture was more than the DRS group (Both P < 0.001).The average dose effect for SRT was 7.8 ± 2.2 PD in the DRS group and 19.2 ± 4.6 PD in the sixth nerve palsy group. Although objective intorsion was significantly induced after SRT, subjective torsion was not significant after surgery in both groups.

CONCLUSION

SRT appears to be more effective in improving primary gaze deviation and head posture in sixth nerve palsy compared with DRS. Subjective torsional and vertical diplopia were rare in both groups.