Vertical Rectus Muscle Transposition Research Articles

Outcomes and Factors Associated with Successful Strabismus Surgery for Abducens Nerve Palsies: A Retrospective Study and Literature Review.

Several studies reported surgical outcomes for abducens nerve palsy, but information on factors that affect treatment success remains lacking. These factors are crucial for developing a treatment plan and providing disease counseling. This study aimed to investigate the outcomes of strabismus surgery for abducens nerve palsy and determine the factors that influence its success, including a review of relevant literature. This retrospective analysis included abducens nerve palsy cases, focusing on surgical interventions and relevant patient data, at the outpatient clinics of Phramongkutklao Hospital from April 1, 2012, to April 30, 2022. A relevant literature review included the surgical success rate and factors that influence surgical outcomes. This study enrolled 32 patients, including 19 with partial and 13 with complete abducens nerve palsy. The overall success rate of strabismus surgery was 78.1%. Trauma was the leading cause of abducens nerve palsy in this population (28.13%). Fisher's exact and Mann-Whitney U-tests revealed that shorter abducens nerve palsy onset and smaller preoperative angle were significantly associated with successful surgical outcomes of strabismus surgery among the groups. In contrast, subgroup analysis revealed that only preoperative smaller angles were significantly associated with good surgical outcomes in horizontal strabismus surgery. However, the vertical rectus muscle transposition group demonstrated no significant factors. The literature review revealed that the success rate of surgery in abducens nerve palsy was 25%-82.6% for horizontal rectus muscle surgery and 46.2%-91% for rectus muscle transposition. The surgical success rate for abducens nerve palsy reached 78.1%, including 78.95% for partial and 76.92% for complete abducens nerve palsy. Notably, a shorter onset preceding surgery and a smaller preoperative angle significantly correlated with successful surgical outcomes one year postoperatively.

Modified Nishida Procedure Combined with Lateral Rectus Disabling for Duane Retraction Syndrome

ABSTRACT Duane retraction syndrome (DRS) is a complex congenital cranial dysinnervation disorder. The choice of surgical procedure in esotropic-DRS depends upon several factors that include: the amount of esotropia in the primary position, the presence and severity of palpebral fissure narrowing, globe retraction, presence of medial rectus muscle (MR) contracture, the likelihood of improving abduction, age of the patient, and the presence of binocularity and stereopsis. In the presence of MR contracture, MR recession is performed either alone (unilaterally or bilaterally) or in conjunction with Y splitting plus recession of the lateral rectus muscle (LR) for reducing globe retraction. MR recession, with or without adjustable sutures, may be simultaneously combined with partial thickness vertical rectus muscle transposition (VRT) or with superior rectus muscle transposition (SRT). We describe a novel combination of surgical procedures in the management of esotropic-DRS in two patients. In our first patient, following an initial MR recession combined with LR disinsertion and periosteal fixation (LRDAPF), a modified Nishida procedure was performed. In our second patient following a prior simultaneous MR recession and LR Y splitting with recession, we combined periosteal fixation of the LR with a modified Nishida procedure of the vertical rectus muscles.

Vertical Tropia Following Horizontal Transposition Surgery.

Aim:The aim of this study was to determine the prevalence of vertical tropia following horizontal transposition of both vertical rectus muscles (HToVR) in patients with Duane syndrome or sixth nerve palsy.Methods:This retrospective study included patients with Duane syndrome or sixth nerve palsy who had undergone HToVR muscles. Data collected included: age, gender, diagnosis, laterality, pre-operative angle of deviation, type of surgery and post-operative angle of deviation at one week, three months and six months. Information on the use of botulinum toxin (BT) ipsilateral medial rectus (MR), additional surgery was performed, and the presence of preoperative and postoperative binocular function and any vertical deviation was collected.Results:There were 11 patients, eight patients with a diagnosis of Duane syndrome and three patients with a diagnosis of sixth nerve palsy. The mean age of the patients was 13 ± 14.79 years (range 5–55 years), four were female. The prevalence of post-operative vertical tropia was 54%. The mean vertical deviation for distance, was 7.6^ ± 2.94 (SD) (range 3^–9^). Stereoacuity was present preoperatively in 5 patients and 8 postoperatively. No patient developed diplopia or received further surgery for the vertical tropia. Of the six patients who had intraoperative BT at the time of the HToVR, four developed a vertical deviation.Conclusion:The prevalence of vertical deviation following HToVR muscles was 54% in our series. None of the patients with an induced postoperative vertical deviation reported diplopia or required further surgery for it.

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

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

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

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

Dual-Augmented Transposition of Vertical Recti in Chronic Abducens Palsy

To report the results of dual augmentation of vertical rectus muscle transposition (VRT) in the treatment of chronic sixth nerve palsy. Retrospective case series. This is a retrospective review of medical records of patients with chronic sixth nerve palsy who underwent dual augmented VRT with or without medial rectus (MR) recession from 2013 to 2016. Data collection included sex, age, laterality, and duration of postoperative follow-up. Pre- and postoperative limitation of abduction and adduction were recorded using a 6-point scale. Improvement of esotropia in prism diopter (PD), head turn in degrees, and limitation of abduction and adduction were reported and analyzed. Fourteen cases were identified. Mean patients' age at the time of surgery was 22.5 years. Postoperatively, esotropia and head turn were corrected by a mean of 31.3 PD and 18.2 degrees, respectively. Limited abduction was improved from -4.3 to -1.6, while in cases that underwent MR recession, adduction declined from 0.4 to -0.3. Postoperative induced small-amplitude hypertropia was reported in 3 cases. Dual augmented VRT was effective in controlling esotropia, head turn, and limited abduction associated with chronic sixth nerve palsy with low rate of induced vertical deviation. Combined MR recession carries a risk of induced limitation of adduction.

Foster Modification of Full Tendon Transposition of Vertical Rectus Muscles for Sixth Nerve Palsy

Since 1907 a variety of muscle transposition procedures for the treatment of abducens nerve palsy has been established internationally. Full tendon transposition of the vertical rectus muscle was initially described by O'Connor 1935 and then augmented by Foster 1997 with addition of posterior fixation sutures on the vertical rectus muscle. Full tendon transposition augmented by Foster belongs to the group of the most powerful surgical techniques to improve the abduction. Purpose of this study was to evaluate the results of full tendon vertical rectus transposition augmented with lateral fixation suture for patients with abducens nerve palsy. Full tendon transpositions of vertical rectus muscles augmented with posterior fixation suture was performed in 2014 on five patients with abducens nerve palsy. Two of the patients received Botox injections in the medial rectus muscle: one of them three months after the surgery and another during the surgery. One of the patients had a combined surgery of the horizontal muscles one year before. On three of the patients, who received a pure transposition surgery, the preoperative deviation at the distance (mean: + 56.6 pd; range: + 40 to + 80 pd) was reduced by a mean of 39.6 pd (range 34 to 50 pd), the abduction was improved by a mean of 3 mm (range 2 to 4 mm). The other two patients, who received besides the transposition procedure additional surgeries of the horizontal muscles, the preoperative deviation at the distance (+ 25 and + 126 pd respectively) was reduced by 20 and 81 pd respectively. The abduction was improved by 4 and 8 mm respectively. After surgery two patients developed a vertical deviation with a maximum of 4pd. None of the patients had complications or signs of anterior segment ischemia. The elevation and/or depression was only marginally affected. There was no diplopia in up- or downgaze. Full tendon transposition of vertical rectus muscles, augmented with lateral posterior fixation suture is a safe and effective treatment method for abducens nerve palsy and in most cases recession of the medial rectus can be avoided. Upgaze and downgaze are affected very slightly. Diverse studies have shown that the risk of anterior segment ischemia is low.

The pursuit of stereopsis

Pediatric ophthalmologists are increasingly expected to promote, preserve, and restore binocular vision. Clinical studies on restoring alignment and stereopsis in the management of amblyopia, esotropia, exotropia, and complex strabismus are reviewed from the perspective of the author's published work and personal experiences. Treatment of amblyopia by means of optical rehabilitation, occlusion, or penalization has been reinforced by medical treatment and perceptual training with monocular or binocular video games. Studies indicate that early management of esotropia and alignment within 8Δ is required for regaining stereopsis. In the surgical management of intermittent exotropia, distance stereopsis by Frisby Davis Distance stereotest can predict better stereopsis, with patients having preoperative distance stereopsis of <70 arcsec less likely to improve after surgery. The surgeon's armamentarium for correcting alignment and restoring binocular vision include procedures such as adjustable, partial vertical rectus muscle transposition in cases of exotropic Duane syndrome and lateral rectus palsy, periosteal fixation of the globe or of the lateral rectus muscle, and medial transposition of the split lateral rectus muscle. The goal for present-day strabismologists is not merely to correct strabismus but also to achieve alignment of eyes in time to ensure normal development of stereopsis in children and to restore alignment and stereopsis in adults.

Efficacy of Vertical Muscle Transpositions with and without Simultaneous Rectus Muscle Recession for Unilateral Sixth Nerve Palsy

We report results of a modified vertical muscle transposition procedure according to the Hummelsheim principle - with and without simultaneous rectus muscle recession - for unilateral sixth nerve palsy. We examine the influence of the duration of the palsy, preoperative angle of squint and preoperative abductive capacity on surgical results of the procedures. Retrospective study of 29 consecutive patients with unilateral abducens nerve palsy who underwent surgery between 2001 and 2012. 21 patients had a modified vertical rectus muscle transposition according to the Hummelsheim principle (HUM); 8 patients had this operation combined with simultaneous medial rectus muscle recession (HUM+I). Surgery was performed at least 9 months after onset of the palsy (HUM: 9 to 98, median 19, mean 30months; HUM+I: 12 to 65, median 25, mean 29 months). The median preoperative angle of squint (far distance) for the HUM group was 27.0° (20.0 to 45.0; mean 28.1°), and for the HUM+I group 30.5° (21.8 to 50.0; mean 33.4°). The median preoperative abductive capacity was for - 1,6 mm before midline (- 8.0 to + 1.2; mean - 1.8 mm) for the HUM group, and - 3.0 mm before midline (- 10.0 to - 1.0; mean - 4.1 mm) for the HUM+I group. The median postoperative angle of squint (far distance) was 0° (- 11.3 to + 20.0; mean 0.1°) for the HUM group, and - 2.3° (- 11.3 to + 12.0; mean - 2.1°) for the HUM+I group. The median postoperative abductive capacity was 1.0 mm (0 to + 3.0; mean + 1.1 mm) for the HUM group, and 1.1 mm (- 1.2 to + 3.0; mean + 0.9 mm) for the HUM+I group. The median reduction of squint angle was 27.0° (9.1 to 45.0; mean 28.0°) for the HUM group, and 36.8° (25.2 to 41.4; mean 35.5°) for the HUM+I group. The median effect on abductive capacity was 2.5 mm (0 to 11.0; mean + 2.9 mm) for the HUM group, and 4.6 mm (2.4 to 8.8; mean + 5.0 mm) for the HUM+I group. In the HUM group, the effect on squint angle reduced with the duration of the palsy, whereas, in the HUM+I group, the effect improved with the duration of the palsy. For patients with unilateral sixth nerve palsy, simultaneous medial rectus recession increases the effect of modified vertical rectus muscle surgery according to the Hummelsheim principle. The duration of the palsy is a relevant parameter for the selection of a sole or combined intervention with medial rectus recession.

Augmented vertical recti transposition with intraoperative botulinum toxin for complete and chronic sixth nerve palsy.

PurposeTo evaluate the results of augmented vertical rectus muscle transposition (VRT) with intraoperative botulinum toxin (BTX) for complete and chronic sixth nerve palsy.MethodsDuring a 10-year period (2004-2014) all patients with chronic and complete sixth nerve palsy and contracted medial rectus (MR) who underwent augmented VRT and BTX injection into the MR enrolled in this study.ResultsIn total, 29 patients (5 bilateral) were enrolled in this study. Preoperative deviation was 45±17.5 Prism Diopter (PD), which was improved to -3.1±13.2 after the operation (P<0.001). Mean preoperative and postoperative abduction limitation was -4.4±1.1 and -1.8±0.9, respectively (P<0.001). The success rate was 76% (deviation within 10 PD of orthotropia). Four patients (13.7%) had hypotropia. In 19 patients with preoperative deviation ≤45 PD, four patients had consecutive exotropia.ConclusionIntraoperative BTX injection with augmented vertical rectus transposition is an effective procedure. In deviation ≤45 there is a risk of overcorrection.

Functional and Motor Outcomes of Strabismus Surgery for Chronic Isolated Adult Sixth Nerve Palsy

Abducens nerve palsy is the most common acquired ocular motor nerve palsy in adults. Chronic cases of abducens palsy often require surgical intervention to relieve disabling diplopia. The goal of this study was to identify factors associated with surgical outcomes in isolated abducens palsy. Medical records of all adult patients from 1988 to 2012 with abducens palsies who underwent strabismus procedures were retrospectively reviewed. Motor alignment, extraocular motility, and sensory outcomes were recorded. Success was defined as absence of diplopia without prisms or face turn, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Eighty-one patients (age range: 20–86 years) met inclusion criteria. Success was achieved in 58% of patients. Final success rates for abducens palsy were 50% for neoplastic, 59% traumatic, 57% for microvascular/unknown, and 67% for other central nervous system causes (p > 0.05). Patients with an underlying neoplastic or traumatic aetiology required more than one strabismus procedure more often than those with microvascular/idiopathic or other central nervous system causes (48% vs. 24%; p = 0.03). For complete abducens palsies, patients who underwent Hummelsheim-type procedures had a higher success rate than those who underwent a full-tendon vertical rectus muscle transposition. (78% versus 35%; p = 0.049). Success rates for strabismus procedures in patients with abducens palsies are similar across all aetiologies. Frequency of re-operation is higher among those patients with neoplastic or traumatic aetiologies for their abducens palsies. Hummelsheim-type procedures have a higher success rate for complete abducens palsies than full-tendon vertical rectus transpositions.

Outcomes of three different vertical rectus muscle transposition procedures for complete sixth nerve palsy

Outcomes of three different vertical rectus muscle transposition procedures for complete sixth nerve palsy

Outcomes in patients with esotropic duane retraction syndrome and a partially accommodative component

Background:The management of Duane retraction syndrome (DRS) is challenging and may become more difficult if an associated accommodative component due to high hyperopia is present. The purpose of this study is to review clinical features and outcomes in patients with partially accommodative esotropia and DRS.Setting and Design:Retrospective, non-comparative case series.Materials and Methods:Six cases of DRS with high hyperopia were reviewed.Results:Of the patients studied, the mean age of presentation was 1.3 years (range: 0.5-2.5 years). The mean amount of hyperopia was + 5D (range: 3.50-8.50) in both eyes. The mean follow up period was 7 years (range: 4 months-12 years). Five cases were unilateral while one was bilateral. Four cases underwent vertical rectus muscle transposition (VRT) and one had medial rectus recession prior to presentation; all were given optical correction. Two (50%) of the four patients who underwent vertical rectus transposition cases developed consecutive exotropia, one of whom did not have spectacles prescribed pre-operatively. All other cases (four) had minimal residual esotropia and face turn at the last follow-up with spectacle correction.Conclusion:Patients with Duane syndrome can have an accommodative component to their esotropia, which is crucial to detect and correct prior to surgery to decrease the risk of long-term over-correction. Occasionally, torticollis in Duane syndrome can be satisfactorily corrected with spectacles alone.

Augmented superior rectus muscle transposition for the treatment of strabismus in Möbius syndrome

Möbius syndrome is a rare congenital disorder characterized by bilateral facial nerve palsy and abducens nerve palsy. It is associated with a wide spectrum of systemic and ocular manifestations; esotropia is commonly the reason for ophthalmic referral. There are few published studies in the literature on strabismus surgery in Möbius syndrome. An augmented vertical rectus muscle transposition in which lateral fixation sutures are used on the transposed vertical rectus muscles (Foster augmentation) has been used to correct esotropia caused by severe sixth nerve palsy and type 1 Duane syndrome. We describe the surgical outcome after treating moderate- to large-angle esotropia in 3 patients with Möbius syndrome with the augmented vertical rectus muscle transposition.

Surgical Management of Chronic Complete Sixth Nerve Palsy

to evaluate the results of strabismus surgery in patients with chronic complete sixth nerve palsy. the patients with negative traction test underwent full tendon vertical rectus muscle transposition, whereas the patients with positive traction test had medial rectus recession and transposition surgery. Traction sutures were used in patients with deviations greater than 65 prism diopters (PD) in addition to medial rectus recession. the mean age of 6 female (35.3%) and 11 male (64.7%) patients was 45.1 ± 20.5 years (range: 13 to 80 years). The average preoperative and postoperative deviations at the primary position were 64.1 ± 14.3 PD (range: 45 to 85 PD) and 9.6 ± 17.6 PD (range: 0 to 75 PD), respectively, with an overall success rate of 76.5%. most of the patients with chronic sixth nerve palsy could achieve good ocular alignment with a surgical approach that is tailored according to the needs of the individual patient.

Long-term results of vertical rectus muscle transposition and botulinum toxin for sixth nerve palsy

To report the long-term outcome of full-tendon vertical rectus muscle transposition combined with chemodenervation of the ipsilateral medial rectus muscle for acquired chronic sixth (abducens) nerve palsy. A retrospective study of all patients treated for severe abduction deficit with transposition plus botulinum toxin over the course of 11 years. Minimum follow-up was 12 months. Main outcome measures were the surgical result and its stability. A total of 22 patients were included. Mean age at the time of surgery was 41.7 ± 19.1 years (range, 4.5-69). The etiologies for the palsy were head trauma (11), tumor (10), and idiopathic (1). Mean follow-up time was 44.2 ± 37.4 months (range, 12-123). The average distance deviation was 38.1(Δ) ± 11.6(Δ) preoperatively, 4.0(Δ) ± 16.1(Δ) 3 months after the operation (p = 0.0004), and 7.9(Δ) ± 8.8(Δ) at 12 months (p = 0.0003), with no subsequent change. At the final examination, on average 44.2 months after the operation, 13 patients (59%) were within 10(Δ) of alignment, 2 (1%) were overcorrected, and 7 (32%) had vertical deviations. The majority of patients (73%) had no double vision in the primary position. No patient developed anterior segment ischemia. Vertical rectus muscle transposition combined with intraoperative botulinum toxin injection into the ipsilateral medial rectus muscle improved alignment in patients with complete chronic sixth nerve palsy. While the effects of treatment may have diminished slightly during the first year after surgery, they remained stable thereafter.

Management of large exotropia with medial rectus muscle transection following endoscopic sinus surgery

To evaluate and compare the effect of surgeries in large exotropic patients who underwent a medial rectus muscle (MR) transection after endoscopic sinus surgery (ESS). In 5 patients with exotropia (XT) and a lack of adduction after ESS, orbital CT revealed a complete transection of the midportion of the MR. 3 patients was treated within 3 months after injury. Foster procedure in 2 patients, augmented Hümmelsheim procedure in 1 other patients. Two patients were treated over 6 months after ESS with lateral rectus contraction. Surgery was divided into two stages. The adduction deficits were divided into -1 through to -8. The patients were followed up for more than than 6 months. Postoperatively, 5 patients showed orthophoria or small exophoria within -5°among which 4 had no diplopia in the primary position, another one avoid diplopia by prism lens. The adduction deficits improved to -2 to -5. Surgical management (vertical rectus muscle transposition) is effective in correcting a large exotropia secondary to a medial rectus transection after ESS. The best time for surgery is 3 months after injury.

Adjustable suture technique for enhanced transposition surgery for extraocular muscles

To evaluate the results of 2 methods of vertical rectus muscle transposition surgery for sixth (abducens) nerve palsy. Retrospective, comparative case series. Historically at our institution, transposed vertical rectus muscles were adjusted toward or attached at the adjacent corners of the lateral rectus muscle ("conventional transposition") before the development of a technique in which adjustable sutures are passed beneath the lateral rectus muscle to attach at its opposite corners ("crossed-adjustable transposition"). Comparative outcomes with these 2 techniques were analyzed in a consecutive series of sixth nerve palsy patients. The change from preoperative to postoperative deviation at distance was 39.3(Δ) ± 22.7(Δ) in 23 conventional transposition cases and 48.5(Δ) ± 27.8(Δ) in 19 crossed-adjustable transposition cases, which demonstrated no statistically significant difference (p = 0.24, t-test). Simultaneous medial rectus weakening was needed less in the crossed-adjustable transposition group (37%) than in the conventional transposition group (83%), and this difference was statistically significant. (p = 0.004, Fisher exact test). Adjustable vertical rectus muscle transposition surgery for the management of chronic sixth nerve palsy, enhanced by passing the adjustable sutures beneath the lateral rectus muscle, requires simultaneous medial rectus muscle weakening less than half as often for satisfactory results.

The Efficacy of Vertical Rectus Transposition and Its Modalities in Patients with Abducens Nerve Palsy

Patients with VIth nerve palsy that does not resolve within 6 months should undergo surgery. The most common procedure used in such cases is transposition of a whole or a part of a vertical rectus muscle combined or not with a resection of the lateral rectus muscle. Commonly, a simultaneous recession of medial rectus muscle with or without prior injection of botulinum toxin is performed. The aim of our study was to evaluate the results of vertical rectus transposition performed in patients with abducens nerve palsy. Nine cases of abducens nerve palsy ware retrospectively analyzed. All patients underwent full ophthalmic and orthoptic examination before and after surgery. All patients underwent vertical rectus muscle transposition to the lateral rectus insertion in the affected eye. Additional procedures included Jensen procedure, botulinum toxin injection, resection of the lateral rectus, recession of the medial rectus on the same side with or without adjustable sutures, and Foster modification of lateral rectus posterior fixation. In all cases, we found a varying degree of postoperative improvement. There was a significant reduction in the strabismus angle for distance and near, increase in abduction of the affected eye, and broadening of the field of binocular single vision. The vertical rectus muscle transposition technique is a safe and successful method of treatment in abducens nerve palsy. Its use together with additional procedures and modifications allows one to achieve orthophoria, improvement of abduction, and larger field of binocular single vision.

Vertical Rectus Muscle Transposition for Correcting Abduction Deficiency in Duane’s Syndrome Type 1 and Sixth Nerve Palsy

Vertical Rectus Muscle Transposition for Correcting Abduction Deficiency in Duane’s Syndrome Type 1 and Sixth Nerve Palsy