Vertical muscle transposition augmented with lateral fixation (Foster) suture for Duane syndrome and sixth nerve palsy

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.

Superior Rectus Transposition in the Management of Duane Retraction Syndrome: Current Insights

Various surgical approaches have been described for the management of Duane retraction syndrome (DRS), a type of congenital cranial dysinnervation disorder (CCDD), the goals of which include correcting the primary position deviation and abnormal head posture (AHP), minimizing globe retraction and overshoots and improving the ocular rotations. Vertical rectus transposition (VRT) is one such technique, found more effective in improving abduction and thereby expanding the field of binocular vision, as compared to horizontal muscle surgery. VRT, however, is associated with the risk of inducing vertical deviations and also poses a risk for development of anterior segment ischemia. To overcome these concerns, transposition of only the superior rectus to the lateral rectus was proposed and evaluated to reveal improvement in alignment, AHP and motility comparable to VRT but with lesser surgical time and fewer post-operative complications. With promising results in the management of DRS, superior rectus transposition (SRT) has been extensively studied and has evolved over the last decade with several modifications to further increase the efficiency and reduce the risk of post-operative complications. This article focusses on the pre-operative considerations while planning SRT in DRS, various approaches and surgical techniques described, and the outcomes and complications of SRT in DRS. The role of SRT in the management of other CCDDs may be explored with further studies.

Medial rectus disinsertion for management of chronic complete sixth nerve palsy

PURPOSE

To report the outcomes of the medial rectus (MR) disinsertion procedure for the management of refractory esotropia (ET) with or without Abnormal head posture (AHP) in chronic complete sixth nerve palsy.

METHODS

This is a retrospective case series of patients with sixth nerve palsy who suffered from residual ET and diplopia following the conventional strabismus surgeries and underwent MR disinsertion procedure between April 2017 and February 2020. This procedure was offered to the patients who declined to use prism and did not wish to perform surgery on the fellow eye. The demographic and clinical data, including sex, age, visual acuity, pre and postoperative angle of strabismus, duction limitations, results of forced duction and force generation tests, details of prior strabismus surgeries, orbital CT scan findings, and follow up duration were collected from the medical records.

RESULTS

Six patients were enrolled in this study. Mean age was 35.0  ±  14.0 years, and mean follow-up was 15.3  ±  5.9 months. The ET at the Primary position (PP) was 35.0  ±  18.4 prism dioptre (PD) before MR disinsertion, which decreased to 14.2  ±  17.4 PD after MR disinsertion procedure. Four cases needed additional complementary surgeries to improve residual ET in PP. No case developed overcorrection. Abduction deficiency was -5.0  ±  1.3 before MR disinsertion, which improved to - 2.8  ±  0.5 units at last follow-up. The mean of induced adduction deficiency was - 2.9  ±  0.4 at last follow-up.

CONCLUSIONS

MR disinsertion can be considered in patients with chronic complete sixth nerve palsy and refractory diplopia when the conventional methods have failed.

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.

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.

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.

Efficacy and complications of transposition surgery in Duane esotropia syndrome

OBJECTIVE

To study the long-term efficacy and the complications of several transposition techniques for the treatment of Duane syndrome. These included, full vertical rectus transposition, partial vertical rectus transposition, transposition without muscle disinsertion, and superior rectus transposition.

MATERIAL AND METHODS

A retrospective study of the patients diagnosed with Duane syndrome, and who underwent any of the different transposition techniques associated or not to the medial rectus recession with a follow-up longer than 12 months. A good result was considered a final deviation≤10 prism dioptres (pd) in primary position, anomalous head posture<10°, and an improvement of the abduction without diplopia.

RESULTS

Seven cases were included (6 women, 6 unilateral), and a mean age of 37.71 years. Pre-operative central gaze esotropia of 28±11.68pd decreased to 6±4.62pd at the final visit (P=.009). The anomalous head posture decreased in 6 patients, and the abduction improved one degree from -3.14 to -2.14 (mean). An induced vertical deviation≤8pd was observed in 4 cases. None experienced diplopia at the final visit. The percentage of reoperations was 71.42%. Only 28.57% had a favourable outcome with a single surgery, which increased to 71.42% with further surgeries at the final follow-up. Mean evolution time was 52±31.65 months.

CONCLUSIONS

Vertical rectus transpositions in Duane syndrome with moderate or severe clinical signs have only been effective in a small percentage of the cases. Most of them required further surgeries to resolve the complications or the under-corrections.

Vertical rectus muscle union combined with lateral rectus plication for complete abducens nerve palsy

PURPOSE

The aim of this study was to report our postoperative results concerning the vertical rectus (VR) muscle union combined with lateral rectus (LR) plication for the treatment of large-angle esotropia (ET) in complete abducens nerve palsy.

METHODS

Medical records from 36 patients who had undergone the VR union procedure for ET treatment due to sixth-nerve palsy between July 2014 and July 2018 at Beyoglu Eye Research and Training Hospital were reviewed. One week before surgery, all patients underwent a 4-IU botulinum toxin A (btx) injection into the ipsilateral medial rectus (MR). All patients then underwent a VR muscle union procedure. A non-absorbable suture was inserted through the lateral muscular margin of each VR muscle at approximately 1/5 the width from the edge at 10 mm distance from the VR insertion. Both sutures were then tied to each other above the LR. Plication of the LR muscle using a non-absorbable suture was performed in all cases.

RESULTS

The study population consisted of 14 (38.9%) females and 22 (61.1%) males. The mean age was 36.31 ± 19.16 years. The mean preoperative deviation angle in primary gaze into distance was 47.77 ± 18.48 prism diopter (PD). The mean deviation angle 1 year after surgery was - 1.0 ± 6.62 PD. Abduction improved from - 4.27 ± 0.46 to - 1.88 ± 0.96.

CONCLUSION

The VR muscle union in combination with LR plication appears to be an effective treatment procedure for complete abducens nerve palsy patients.

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.

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.

Comparison of the efficiency of various muscle transposition procedures using a novel three-dimensional model

AIM

To investigate the performance of a newly developed three-dimensional (3D) biomechanical model in various transposition procedures for correction of complete sixth nerve palsy with educational purpose.

METHODS

A 3D biomechanical eye model was created using Hyperworks software based on geometry data and the biochemical properties of the eyeball and extraocular muscles. A complete sixth nerve palsy model was achieved via modification of lateral rectus muscle strength. Four different muscle transposition procedures (the Hummelsheim, Jensen, Foster, and muscle union procedures) were set up, and the objective surgical effect of each procedure was calculated using 3D model simulation.

RESULTS

In the 3D simulation, sixth nerve palsy was modeled by rotating the eye 34.16 degrees in the medial direction, consistent with 70 prism diopter (PD) esotropia. In surgical model simulation, the Hummelsheim procedure resulted in a 28 PD reduction of total deviation, the Jensen procedure achieved a 34 PD reduction, the Foster procedure led to a 57 PD reduction, the muscle union procedure yielded a 57 PD reduction in esotropia in sixth nerve palsy.

CONCLUSION

The 3D simulation provided a consistent model of sixth nerve palsy and objective data excluding the potential for variation of surgical skill. It could also help predict surgical outcomes.

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

PURPOSE

To compare the effectiveness of superior rectus transposition and medial rectus recession (SRT/MRc) vs inferior and superior rectus transposition (VRT) for acquired sixth nerve palsy.

DESIGN

Consecutive, interventional case series.

METHODS

The medical records of a consecutive series of patients with acquired sixth nerve palsy who underwent VRT or SRT/MRc by a single surgeon were reviewed. The preoperative and postoperative findings were compared between the 2 groups.

RESULTS

Eight patients (mean age, 46.8 years) underwent SRT/MRc and 8 patients underwent VRT (mean age, 51.1 years). Lateral fixation was performed on all but 4 patients in the VRT group. Preoperative esotropia in primary position and abduction deficit were similar in both groups (SRT/MRc, 41.9 prism diopter [PD], -4.6; VRT, 55.6 PD, -4.5; P = .195, 1.0). The SRT/MRc group underwent a mean MR recession of 6 (range, 5-7) mm. Four patients in the VRT later underwent MR recession (mean 5.3 mm, range 5-6 mm). In addition, 5 patients in the VRT group had 1 or more botulinum toxin injections in the medial rectus muscle. No additional procedures were performed in the SRT/MR group. Fewer additional procedures were performed with SRT/MR (SRT/MR, 0; VRT, 1.8 ± 1.2; P < .010). At last follow-up, residual esotropia (SRT/MRc, 7.1 PD; VRT, 10.3 PD; P = .442) was similar in both groups, but abduction was better in the SRT/MRc group (SRT/MR, -3.0 ± 0.7; VRT, -3.8 ± 0.4; P = .038). There were no new persistent vertical deviations or torsional diplopia.

CONCLUSIONS

Final outcomes were similar with SRT/MRc vs VRT. However, fewer additional surgical procedures were needed with SRT/MR.

What's new for us in strabismus?

Strabismus is one of the most challenging subspecialties encountered in the field of ophthalmology. The concept of etiology of strabismus is being advanced with the development of newer imaging modalities and increased understanding of the genetics of strabismus. Imaging is also being used to aid in the planning of strabismus surgery. Newer horizons are being explored in the amblyopia management. The good old eye-pad is being replaced with the iPad. Early detection of loss of stereopsis is being used to decide the timing for strabismus surgery. Improvement of binocular summation has been discovered as a benefit of corrective strabismus surgery. Newer surgical techniques such as new transposition procedures are being developed to correct complex strabismus. Strabismus surgeries aided by adjustable sutures have increased the precision of a strabismologist. A new light has been thrown on the psychosocial impact of strabismus. A present-day strabismologist has advanced from the goal of ocular alignment to a bigger perspective "to regain the paradise lost: stereopsis."

Pearls and pitfalls in the management of Duane syndrome

Duane syndrome (DS) is a common form of congenital cranial dysinnervation disorders. The ocular motility pattern lies in a wide clinical spectrum, and the choice of treatment must be individualized depending on the severity of the clinical findings. There is no perfect method of treatment and no real “cure” in DS. In this paper, the aim is to give some guidelines to the reader for selection of the most appropriate treatment method for the patient.

Vertical rectus transpositions in sixth nerve palsies

PURPOSE OF REVIEW

There are many surgical options to address a sixth nerve palsy including transpositions of the vertical recti to the lateral rectus. This review will summarize the results from variations on transpositions as they apply to sixth nerve palsies.

RECENT FINDINGS

Transposition of both vertical recti with posterior fixation creates the greatest correction of esotropia in primary position with largest field of single vision. Transposition of the superior rectus alone preserving anterior segment circulation achieves effects similar to transposition without posterior fixation. Augmentation with partial transposition also creates similar improvement in esotropia with possibilities for adjustable sutures and circulation preservation.

SUMMARY

These various options on transpositions allow options to specifically address surgeon preferences and patient needs to select the appropriate surgery.

A 1-Year Review of Amblyopia and Strabismus Research

PURPOSE

This current review highlights some of the literature published in the past year from April 2013 to May 2014.

DESIGN

Literature Review.

METHODS

The present review is based on an extended search for pertinent articles on amblyopia and strabismus published during the specified period.

RESULTS

Many articles are often not very comparable to one another because of a lack of randomized clinical trials with most of the studies being retrospective in nature. There is often disagreement on some terminology. Typically, the definition of binocular vision is rarely related to the tests used for evaluating it.

CONCLUSIONS

The authors conclude that adult strabismus patients seem to gain benefits from corrective surgery not only for their ocular misalignment, but also for social anxiety levels that may be associated with improvements in their quality of life and disability levels.