Recession of the inferior rectus muscle in Graves’ orbitopathy

Update on the surgical management of Graves' orbitopathy

Graves' orbitopathy (GO) is a complex autoimmune disorder of the orbit that causes the eye to appear disfigured. GO is typically associated with Graves' disease, an inflammatory autoimmune condition that is caused by thyrotropin receptor autoantibodies. Although our knowledge of the pathophysiology of GO has improved, its exact pathogenesis remains unclear. Some patients suffer from disfigurement, double vision, and even vision loss rather than hyperthyroidism. The disease severity and activity prompt different treatments, as the signs of GO are heterogeneous, so their management can be very complex. Despite medical advances, the first-line treatment for moderate-to-severe active GO is still glucocorticoids, while surgery can be critical for the treatment of chronic inactive GO. Surgery is sometimes required in the acute phase of the disease when there is an immediate risk to vision, such as in dysthyroid optic neuropathy. Most surgeries for GO are rehabilitative and subdivided into three categories: decompression, strabismus repair, and lid surgery. This review is a basic overview of the field, with up-to-date knowledge of the surgical techniques for GO. We review and summarize recent literature on the advances in surgery for GO to provide up-to-date insights on the optimal surgical treatment for GO.

Elongation of the inferior rectus tendon with fascia lata graft for large vertical squint angles in patients with Graves' orbitopathy

PURPOSE

To investigate the use of fascia lata (FL) grafts for inferior rectus muscle (IRM) tendon elongation in patients with large vertical squint angles with Graves' orbitopathy (GO).

METHODS

In this retrospective study, we included a consecutive series of 20 eyes of 13 patients with GO who underwent IRM tendon elongation with FL. Orthoptic and ophthalmologic examinations including measurement of the head posture, the extent of deviation in primary position (PP), elevation, motility, and binocular diplopia at the tangent of Harms were conducted preoperatively and after a mean postoperative time of 10.8 (5.0-35.0) months in all patients.

RESULTS

The mean total repositioning distance was 9.3 ± 3.6 (3.5-16.0) mm. Postoperatively, we found a significant increase in elevation (5.4 ± 2.4 vs. 2.7 ± 2.4 mm preoperatively, p = 0.011). A significant reduction in vertical squint angle (2.8 ± 3.7 vs. 20.2 ± 18.8 Δ preoperatively, p = 0.004), chin elevation (2.3 ± 3.7 vs. 12.9 ± 6.3° preoperatively, p < 0.001), extorsion in PP (0.1 ± 3.8 vs. 8.4 ± 7.8° preoperatively, p = 0.002), and in elevation (1.8 ± 4.8 vs. 11.1 ± 10.9° preoperatively, p = 0.004) occurred postoperatively. A mean dose-effect relation of 2.6 ± 2.9 Δ/mm was calculated. Postoperatively, the lower eyelid retraction was significantly increased (1.5 ± 1.4 vs. 0.4 ± 0.5 mm preoperatively, p = 0.005).

CONCLUSION

IRM tendon elongation with FL is a feasible and effective procedure without relevant risk for surgery-related complications.

Long-term follow-up of surgical treatment of thyroid-associated orbitopathy restrictive strabismus

OBJECTIVE

Thyroid-associated orbitopathy (TAO) is the most frequent cause of extraocular muscle enlargement, with consecutive restrictive strabismus. The main muscles involved are inferior and medial rectus, resulting in horizontal esotropia and/or vertical strabismus. Surgery may either establish or improve binocular single vision. The aim of the present study is to describe long-term follow-up of patients who underwent horizontal or vertical TAO strabismus surgery.

METHODS

This observational retrospective study included 29 patients suffering from either vertical or horizontal TAO strabismus and diplopia, of whom 11 underwent bilateral medial recti muscle recession (Group A) and 18 underwent unilateral inferior rectus muscle recession (Group B). The endpoint of the study was the assessment of changes in deviation angle and diplopia across four time points (baseline, 7 days, 6 months, and 24 months) in each group.

RESULTS

In Group A, the horizontal deviation angle significantly decreased 7 days after intervention (p < 0.001), without modifications overtime. In Group B, both deviation angles in primary and down-gaze position significantly decreased from baseline, both 7 days after surgery (p < 0.001) and at 6 months (p = 0.040). An overcorrection, with an inversion of vertical deviation angle, was observed across the different time points.

CONCLUSIONS

Horizontal TAO strabismus correction leads to significant improvements of deviation angle and diplopia, with a stable undercorrection overtime. Inferior rectus recession leads to more unstable results, with a trend towards overcorrection limited to the first 6 months after surgery.

Primary and secondary superior rectus recessions to correct vertical deviations in Graves' orbitopathy patients

PURPOSE

Patients with vertical strabismus and consecutive diplopia due to Graves' orbitopathy (GO) might need recession of the rectus superior muscle. The aim of this retrospective analysis is to provide dose-effect values and motility analysis for these patients.

METHODS

Dose-effect relations (deviation reduction in primary position per amount of recession in mm), monocular excursions and size of the field of binocular single vision (BSV) were evaluated in three different groups of patients. Group 1 (n = 33) patients with primary fibrosis of superior rectus muscle undergoing recession of the ipsilateral rectus superior, Group 2 (n = 14) superior rectus muscle recession after recession of inferior rectus on the contralateral eye and Group 3 (n = 15) simultaneous ipsilateral superior rectus recession and contralateral inferior rectus muscle recession. Surgery was performed using the dose-effect for inferior rectus recession of 4 prism dioptre (PD,Δ ) reduction/per mm recession and the intraoperative traction test.

RESULTS

Restoration of BSV in the central 20° of gaze could be reached in 88%, 79% and 67% of patients in the three groups, respectively. Restoration of BSV in downgaze (up to 30°) was a little less successful, 79%, 57% and 53%, respectively. The median dose-effect was 3.2Δ reduction/mm recession in Group 1 (Spearman correlation r = 0.75, p < 0.0001) and 3.3Δ /mm in Group 2 (n.s.) and 4Δ /mm in Group 3 (r = 0.67, p = 0.016). The basis for the improvement was the symmetrization of ductions.

CONCLUSION

If superior rectus recession is necessary in GO, higher dosing around 3Δ reduction/per mm recession should be applied. In case of large deviations, combined vertical surgery (inferior rectus and superior rectus contralateral) is required and reasonable (low cyclotorsion). Single-step or two-step procedures lead to similar results.

Initial Postoperative Alignment in Strabismus Related to Thyroid Eye Disease

PURPOSE

To investigate the surgical outcome according to the initial postoperative angle of deviation in patients with thyroid eye disease.

METHODS

The medical records of patients who underwent strabismus surgery were retrospectively reviewed. The patients were divided into overcorrection (> 5 prism diopters [PD]), full correction, or undercorrection (> 5 PD) groups, according to the angle of deviation on postoperative day 1. The surgical outcome was considered successful when there was no diplopia vertically (< 5 PD) and horizontally (< 10 PD) at primary gaze. Surgical success rates were evaluated according to the initial postoperative angle of deviation at the final visit.

RESULTS

Seventy-eight patients were enrolled in this study. The mean age of the patients was 53.4 ± 9.5 years, and the mean follow-up duration was 17.4 ± 8.7 months. There were 51 patients with hypotropia and 27 patients with esotropia. Success rates for hypotropia were higher in the undercorrection (80.0%) and full correction (66.7%) groups than in the overcorrection (35.7%) group on postoperative day 1 (P = .02). Regarding esotropia, the success rates were higher in the undercorrection (84.6%) and full correction (83.3%) groups than in the overcorrection (37.5%) group on postoperative day 1 (P = .02). Reoperation for residual or overcorrected strabismus was performed in 15 patients (29.4%) with hypotropia and 7 patients (25.9%) with esotropia.

CONCLUSIONS

Intended minimal undercorrection or full correction after hypotropia and esotropia surgery during early postoperative periods could improve surgical success rates in patients with thyroid eye disease. [J Pediatr Ophthalmol Strabismus. 2021;58(1):23-27.].

Changes in horizontal strabismus after inferior rectus muscle recession with or without nasal transposition in thyroid eye disease: A retrospective, observational study

Since the inferior rectus muscle (IRM) is a secondary adductor, it is expected to commonly observe esotropia in thyroid-associated inferior rectus myopathy, but this can be improved after the IRM recession. However, variable outcomes regarding the changes in horizontal strabismus after IRM recession ± IRM nasal transposition have been encountered in patients with thyroid eye disease (TED). We, therefore, examined the changes in 62 patients with TED in this retrospective, observational, comparative study. The patients were classified into 3 groups based on the results of postoperative changes in horizontal strabismus: Groups A (reduced esotropia), B (unchanged esotropia), and C (increased esotropia). Consequently, Groups A, B, and C included 23 (38.7%), 11 (17.7%), and 27 (43.5%) patients, respectively. In the multivariate linear regression analysis, the angle of preoperative esotropia (P < 0.001) and the amount of IRM nasal transposition (P = 0.049) were significant predictors of postoperative changes in horizontal strabismus. The results of our study will be helpful to ophthalmologists for formulating an effective preoperative surgical plan.

Surgical treatment of strabismus in thyroid eye disease: characteristics, dose-response, and outcomes

PURPOSE

To describe the surgical management, dose-response, and postoperative outcomes of strabismus surgery in patients with thyroid eye disease.

METHODS

The medical records of patients operated on between 2014 and 2018 were reviewed retrospectively. Patient characteristics and surgical data were collected. Motor success was defined as vertical deviation of ≤5^Δ and horizontal deviation of ≤10^Δ; sensory success, as no diplopia in primary gaze.

RESULTS

A total of 76 patients (mean age, 62.2 ± 12.9 years; 50 females) underwent 87 surgeries, most commonly unilateral inferior rectus recession (unilateral IR, 48%) and bilateral medial rectus recession (bilateral MR, 23%). Motor success was achieved in 69% and sensory success in 58%. For unilateral IR surgery, the dose-responses were 3.25^Δ/mm (SE = 0.616; β = 0.650; P < 0.001) at distance and 2.48^Δ/mm (SE = 0.752; β = 0.472; P = 0.002) at near; for bilateral MR surgery, 3.93^Δ/mm (SE = 0.997; β = 0.680; P = 0.001) at distance and 5.05^Δ/mm (SE = 1.374; β = 0.655; P = 0.002) at near. Median (Q₁, Q₃) postoperative drift was toward overcorrection for both procedures (unilateral IR, -2^Δ [-8, 0] at distance and -2^Δ [-7, 0] at near; bilateral MR, -2^Δ [-8, 2] at distance and -2^Δ [-10, 0] at near). Sex, age, duration of strabismus, prior orbital decompression, and concurrent vertical and horizontal procedures were not associated with dose-response or postoperative drift.

CONCLUSIONS

Concurrent vertical and horizontal surgery did not affect the motor success rate, dose-response, or postoperative drift. Although unilateral IR surgery had a larger dose-response at distance, bilateral MR surgery had a larger dose-response at near. Most procedures tended to have a postoperative drift toward overcorrection.

Objective and subjective outcomes of strabismus surgery in Graves' orbitopathy: a prospective multicentre study

PURPOSE

To assess the change and interrelationship of the field of binocular single vision (BSV) and the quality of life (QoL), tested with two different tools, after one or two strabismus surgeries in patients with Graves' orbitopathy (GO).

METHODS

Prospectively, consecutive patients with GO who were scheduled for their first strabismus surgery were recruited from five centres specialized in the treatment of GO. One week preoperatively and 3 months after the last operation, a full ophthalmic and orthoptic examination was performed. Change in field of BSV, GO-QoL and thyroid eye disease-QoL (TED-QoL) was recorded.

RESULTS

A total of 59 met all the eligibility criteria of whom 15 underwent two strabismus operations. The median (interquartile range) preoperative score of the field of BSV was 0 (0-0), which improved to 73 (53-85) after the correction(s) (p < 0.001). After the first surgery, a significant higher score of the field of BSV was found in the patients who underwent one operation (76; 60-86) compared with those who underwent two 0 (0-63) operations (p < 0.001). After the second surgery, this score increased to 62 (40-76; p = 0.05). A moderate correlation was found between the score of the field of BSV and the GO-QoL visual functioning (VF) questionnaires (r = 0.485; p < 0.001). Both the GO-QoL and TED-QoL for VF and appearance (AP) showed significantly higher scores after the treatment (p < 0.001).

CONCLUSION

After strabismus surgery in GO patients, both the field of BSV and quality of life questionnaires increase. In approximately 30% of the patients, an additional strabismus surgery is performed. This second surgery significantly expands the field of BSV and the quality of life.

Medial and mediolateral orbital decompression in intractable Graves' Orbitopathy

OBJECTIVE

Graves' Orbitopathy (GO) has well established treatment guidelines; however, its management is still controversial. The aim was to evaluate the results of medial and mediolateral orbital decompression (OD) in intractable GO.

METHODS

Retrospective chart review of all patients with advanced stages of GO, who underwent medial (1-wall) or mediolateral (2-wall) OD between May 2012 and November 2014 in our institution. Ophthalmologic examinations included visual acuity, Hertel exophthalmometry (proptosis), intraocular pressure (IOP), visual field (30:2) and diplopia. Follow-up was performed 1 week, 3 months and 1 year postoperatively. Additionally, a questionnaire was used to investigate subjective benefits.

RESULTS

The study included 34 eyes of 20 patients. In our study, GO patients who underwent mediolateral OD had significantly higher IOP preoperatively (p<0.05) and lower visual acuity, proptosis and visual field compared with patients who underwent medial OD. After 1- and 2-wall OD, visual acuity, proptosis, visual field and IOP in upgaze improved significantly. Using a questionnaire, the patients reported significant improvements in impaired vision, eye pain and pressure, vitality and social life. 94% of all patients reported they would repeat the operation. After 2-wall OD, the surgical scar had little effect.

CONCLUSION

With GO patients in advanced stages, both medial (1-wall) and mediolateral (2-wall) OD procedures are convincing therapeutic options. In more advanced GO stages with high IOP, 2-wall OD should be prioritized, as mediolateral OD had superior long-term functional outcomes.

Correction of Excyclotropia by Surgery on the Inferior Rectus Muscle in Patients with Thyroid Eye Disease: A Retrospective, Observational Study

Purpose

To examine the characteristics of excyclotropia correction through surgery on the inferior rectus muscle in patients with thyroid eye disease.

Methods

This was a retrospective, observational study at a single institution. We reviewed 36 patients who had undergone unilateral inferior rectus muscle recession, with or without nasal inferior rectus muscle transposition. The following factors were investigated as possibly influencing excyclotropia correction: inferior rectus muscle thickness, degree of adipose change in the inferior rectus muscle, smoking status, history of orbital radiotherapy, and the amount of inferior rectus muscle recession. Using T1-weighted coronal magnetic resonance imaging, we measured the cross-sectional area of the inferior rectus muscle at its largest point, as well as the bright-signal area of the inferior rectus muscle, which reflects intermuscular adipose change. We then calculated the percentage internal bright-signal area at the point of the largest inferior rectus muscle cross-sectional area. The history of orbital radiotherapy was graded using a binary system. We evaluated correlations among excyclotropia correction, the amount of nasal inferior rectus muscle transposition, and the possible influencing factors listed, using stepwise multiple regression analyses.

Results

The multiple regression model demonstrated a significant relationship among excyclotropia correction, amount of nasal inferior rectus muscle transposition, and the amount of inferior rectus muscle recession (Y_CORRECTION = 8.546X_{TENDON WIDTH} + 0.405X_RECESSION− 0.908; r = 0.844; adjusted r² = 0.695; P < 0.001).

Conclusions

Excyclotropia correction was correlated with the amount of nasal inferior rectus muscle transposition and the amount of inferior rectus muscle recession, but not with the other factors. The regression model presented in this study will enable us to determine more precisely the amount of nasal inferior rectus muscle transposition in patients with excyclotropia of various angles.

Surgical Responses of Medial Rectus Muscle Recession in Thyroid Eye Disease-Related Esotropia

We evaluate the surgical outcomes and surgical responses of medial rectus muscle (MR) recession patients with thyroid eye disease (TED)-related esotropia (ET). The surgical dose-response curves 1 week postoperatively and at the final visit were analyzed. Univariable and multivariable linear regression analyses were applied to investigate factors influencing surgical dose-response. A total of 43 patients with TED-related ET that underwent MR recession were included. The final success rate was 86.0% and the rate of undercorrection was 14.0%. The surgical dose-response curves of TED-related ET showed a gentle slope compared with those of standard surgical tables. In the univariable model, simultaneous vertical rectus muscle recession was the only significant factor influencing surgical dose-response of MR recession in TED-related ET (β = -0.397, P = 0.044). In a model adjusted for age, sex, type of surgery, and preoperative horizontal angle of deviation, simultaneous vertical rectus muscle recession showed marginal significance (β = -0.389, P = 0.064). The surgical dose-response curve of TED-related ET was unique. Simultaneous vertical rectus muscle recession was associated with increased surgical dose-response in TED-related ET.

Predictability of horizontal versus vertical muscle surgery outcomes in thyroid eye disease

Surgical repair of vertical muscles in thyroid eye disease (TED) is believed to yield more unpredictable results than horizontal muscle surgery. The purpose of this study is to determine if the short-term outcomes for strabismus surgery in TED are equally predictable for horizontal and vertical muscle surgery. We retrospectively reviewed the charts of 27 consecutive patients who underwent strabismus surgery for TED from a single surgeon's practice. Eligibility for inclusion in the study included biochemically stable thyroid disease for at least a year and stable orthoptic measurements for at least 6 months prior to surgery. Nine patients had surgery only on vertical rectus muscles, three only on horizontal, and fifteen on both vertical and horizontal rectus muscles. Mean follow-up was 2.4 ± 5.2 months. In primary gaze at 6 m, a mean horizontal deviation of 16.6 ± 22.3 PD, and a mean vertical deviation of 19.7 ± 14.1 PD were measured pre-operatively. Post-operatively, this measured 2.3 ± 8.4 PD horizontally and 2.1 ± 7.8 PD vertically (p = 0.933). There was no statistically significant difference between post-operative horizontal and vertical deviations in elevation, depression, adduction, and abduction. Nine patients required reoperation to attain satisfactory ocular alignment; seven of these cases involved repeat surgery on vertical muscles, while two cases required operation on both horizontal and vertical muscles. Results suggest that surgical outcomes of both horizontal and vertical muscle surgery are equally predictable in stable TED; however, reoperation rates were higher for vertical muscles compared to horizontal muscles.

Proposal of success criteria for strabismus surgery in patients with Graves' orbitopathy based on a systematic literature review

Proposal of success criteria for strabismus surgery for patients with Graves' orbitopathy (GO) based on a systematic review of the literature. We performed a systematic search of OVID MEDLINE, OVID Embase, the Cochrane Central Register of Controlled Trials (CENTRAL) and the publisher subset of PubMed, to identify studies reporting on success criteria of strabismus surgery in GO. In addition, we handsearched several orthoptic journals and proceedings of strabismological congresses. Of the 789 articles retrieved, 42 articles described success criteria for strabismus surgery in GO. Most studies defined success in terms of a subjective diplopia-free field in primary and down gaze. Almost half of the studies used a graded scale (excellent, good, acceptable and failure) to describe the outcome of surgery. Three of the eligible studies described a tool to quantify the field of single vision in detail. Quality of life was not reported as an outcome measure in any of the published studies. In conclusion, success criteria for strabismus surgery in patients with GO are poorly defined and no consensus is available. The lack of standardization hampers comparative studies and thus the search for the best surgical treatment for diplopia in patients with GO. Therefore, we propose strict success criteria including a tool for quantification of remaining diplopia plus a disease-specific quality of life questionnaire (the GO-QoL).

Outcome of inferior and superior rectus recession in Graves' orbitopathy patients

PURPOSE

To evaluate the surgical effect of unilateral inferior rectus recession (IR-group) with or without a recession of contralateral superior rectus (IR-SR-group) on squint angle and motility restrictions in Graves' Orbitopathy (GO) patients.

DESIGN

Retrospective case series.

MATERIALS AND METHODS

Primary outcome parameters were the changes of squint angle 3 months and 6-12 months postoperatively. As in a previous study, success was defined as a postoperative vertical squint angle of ≤3° in primary position and on downgaze. Secondary outcome parameters were the influence of surgery on duction range and influence of muscle size on dose-effect response.

RESULTS

Fifty-six patients were included in the study; 31 patients in the IR-group and 25 patients in the IR-SR-group. The amount of (fixed suture) recession ranged from 2 mm to 7 mm. Vertical deviations in primary position changed from 8.0° [95% CI 6.6-9.7°] to 1.0° [95% CI -0.4-6.5°] in the IR-group and from 17.0° [95% CI 15.7-20.0°] to 1.5° [95% CI 0.8-2.9°] in the IR-SR-group. The success rate was 74% in the IR-group and 64% in the IR-SR-group. Elevation significantly improved in both groups (IR-group p = 0.007; IR-SR- group p = 0.000). The volume of vertical rectus muscles as assessed on CT-scans did not influence the dose-effect response.

CONCLUSIONS

The highest success rate and highest reduction of depression was found in the IR-group. The total duction range remained stable after strabismus surgery (IR-group) or improved (IR-SR-group). Both squint angle and cyclodeviation remained stable during long time follow-up (6-12 months after surgery).

Predictors of the Dose-Effect Relationship regarding Unilateral Inferior Rectus Muscle Recession in Patients with Thyroid Eye Disease

Purpose. To evaluate whether inferior rectus muscle (IRM) thickness, the degree of adipose change in the IRM, smoking status, and the previous history of orbital radiotherapy can predict the dose-effect relationship regarding unilateral IRM recession in thyroid eye disease (TED). Methods. Twenty-five patients were retrospectively reviewed. We calculated the largest IRM cross-sectional area and evaluated the degree of adipose change in the IRM using magnetic resonance imaging. The degree of adipose change and smoking status were classified using grading scales (0-3); previous orbital radiotherapy was graded as 0 when a history was not available and 1 when it was available. The correlation between the dose-effect relationship and the hypothesized predictive factors was evaluated using stepwise multiple regression analysis. Results. The multiple regression model, with the exception of the history of the previous orbital radiotherapy, estimated a significant dose-effect relationship for the parameters evaluated (Y DOSE-EFFECT = 0.013X IRM AREA  - 0.222X ADIPOSE  - 0.102X SMOKING + 1.694; r = 0.668; adjusted r (2) = 0.367; P = 0.005). Conclusions. The dose-effect relationship regarding unilateral IRM recession in TED could be predicted using IRM thickness, degree of intramuscular adipose change, and smoking status but could not be predicted using the previous orbital radiotherapy history.