Factors affecting postoperative stereopsis in acquired nonaccommodative esotropia

Acquired comitant esotropias - comparison of surgical outcomes of accommodative vs non-accommodative types

Purpose: To compare the motor and sensory outcomes of strabismus surgery and the factors affecting surgical success in acquired acute non-accomodative esotropia (ANAET) and partially accommodative refractive esotropia (pARET). Methods: A retrospective chart review of patients with ANAET and pARET who underwent unilateral or bilateral horizontal rectus muscle surgery between January 2020 and December 2021 was conducted. Patients with postoperative follow-up of at least six weeks were included. Patients with pattern deviation, lateral incomitance, and near-distance disparity were excluded. Motor success was defined as a postoperative deviation within eight prism diopters of orthophoria. Sensory success was defined as presence of binocular single vision (BSV) for both distance and near (Worth four dot test). The effect of factors like age at onset, age at surgery, amblyopia before surgery, duration of squint before treatment, presence or absence and magnitude of vertical deviation, preoperative angle of deviation, and spherical equivalent on the motor and sensory success in each group were analyzed and compared. Results: 38 patients with ANAET and 33 patients with pARET were included. The mean age of onset of esotropia was 8.55 ± 4.65 years and 4.39 ± 2.27 years (p < .001) and the mean age at surgery was 10.62 ± 4.99 years and 7.89 ± 2.84 years (p = .006) in the ANAET and the pARET group respectively. The mean duration of the final follow-up was 38.51 weeks in the ANAET and 48.68 weeks in the pARET group (p = .089). Patients were successfully aligned for both distance and near in 81.5% of patients in the ANAET and 78.9% of patients in the pARET group at the final follow-up (p. 0.775). A BSV for both distance and near at the final follow-up was seen in 81.2% vs 66.6% of patients in the ANAET and the pARET group respectively (p = .25). A good near stereoacuity (<120 arcsecs) was seen in 60.6% and 41.9% of the ANAET and the pARET groups respectively (p = .175). The percentage of patients in the ANAET group who had orthophoria, any esodeviation, and any exodeviation for distance at the final follow-up was 63.1%, 34.2% and, 2.6%. The percentage of patients in the pARET group in similar categories was 36.3%, 42.4% and, 21.2%. None of the demographic and preoperative factors were found to affect the surgical outcomes in the two groups. Conclusions: The motor and sensory outcomes were similar in the two groups. A higher proportion of ANAET patients remained orthophoric during the follow-up. The patients in the pARET group showed a tendency toward exodrift.

Basic acquired nonaccommodative esotropia patients managed with surgery; a study of 2102 patients

INTRODUCTION

Several studies investigated preoperative clinical features of patients with basic-acquired nonaccommodative esotropia (BANAET); however, their sample sizes were small, and they did not compare the clinical features among cases that needed different surgery times. The main purpose of this study is to compare the preoperative clinical features of patients with BANAET managed with one surgery with patients who underwent two or more strabismus surgery over 10 years.

METHODS

This historical cohort study was performed on the hospital records of 13,252 Iranian strabismic patients who underwent surgery at Farabi eye hospital, Tehran, Iran, from 2012 to September 2022. Of those, 2102 cases with BANAET were selected as the sample size. Data collected included sex, age at the time of first surgery, corrected distance visual acuity (CDVA), refractive error, presence of amblyopia, angle of deviation, and times of surgery.

RESULTS

The mean age was 18.9 ± 15.6 [1200 (57.1%) males and 902 (42.9%) females] and the median age was 14 years. In 1599 (76.1%) patients, esotropia was managed with one surgery; however, 342 (16.3%) cases were managed with two surgeries and 161 (7.6%) patients underwent three or more surgeries. The mean angle of horizontal deviation at distance and near in patients managed with two and ≥3 surgeries was significantly higher than in cases managed with one surgery (P < .001). Amblyopia was observed in 289 (18.1%) patients who were managed with one surgery, 69 (20.2%) patients with two surgeries and 43 (26.7%) patients with three or more surgeries (P < .001). Patients with BANAET managed successfully with only one surgery were younger, had better CDVA, lower astigmatism and less horizontal angle of deviation at distance and near than those who underwent two or more surgeries (all P < .001).

DISCUSSION

The higher astigmatism, lower CDVA, greater angle of horizontal deviation, and higher frequency of amblyopia were found in the preoperative examinations of BANAET patients managed with two or more surgeries compared with cases managed with only one surgery.

Augmented-Dose Unilateral Recession-Resection Procedure in Acute Acquired Comitant Esotropia

PURPOSE

To compare the surgical amount of unilateral medial rectus recession and lateral rectus resection (RR) in patients with acute acquired comitant esotropia (AACE) versus common forms of esotropia and to provide dose-response reference for surgical planning in AACE.

DESIGN

Retrospective study.

PARTICIPANTS

Consecutive patients who underwent unilateral RR for AACE or common forms of esotropia correction from January 2018 to January 2022. Only patients who achieved motor and sensory success with a minimum follow-up of 3 months were analyzed.

METHODS

Group differences in the amount of medial rectus (MR) recession and lateral rectus (LR) resection were analyzed using multivariate regression models. Surgical dose responses in AACE were analyzed using multivariable regression models. Regression models were performed with and without adjustment for clinical confounders. Piecewise analysis was used to detect segmented results.

MAIN OUTCOME MEASURES

Group difference in surgical amount and dose responses of unilateral RR in AACE.

RESULTS

Fifty-four patients with AACE and 98 patients with common forms of esotropia were included. To correct comparable deviations, surgical amount performed was significant larger in AACE patients, with the adjusted group differences of 0.49 mm (95% confidence interval [CI], 0.34-0.65 mm; P < 0.001) in MR recession and 1.68 mm (95% CI, 1.25-2.11 mm; P < 0.001) in LR resection in patients with deviation < 40 prism diopters (Δ) and with a group difference of 1.22 mm (95% CI, 0.76-1.68 mm; P < 0.001) in LR resection in those with deviation ≥ 40 Δ. In AACE patients, in the adjusted model taking into account the intercept, dose responses of MR recession and LR resection in patients with deviation < 30 Δ were 5.11 Δ/mm (95% CI, 0.98-9.23 Δ/mm; P = 0.02) and 2.51 Δ/mm (95% CI, 0.57-4.45 Δ/mm; P = 0.02), respectively, and for those with deviation ≥ 30 Δ, the dose response of additional LR resection was 5.48 Δ/mm (95% CI, 4.56-6.40 Δ/mm; P < 0.001) to correct remaining deviation beyond 30 Δ.

CONCLUSIONS

These findings provide quantitative evidence that augmented-dose unilateral RR should be performed in AACE for favorable surgical outcomes. The new surgical dose calculation proposed provides reference for surgical planning.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Short-Term Near Stereoacuity Improvements Following Favorable Surgical Alignment in Exotropic and Esotropic Patients

PURPOSE

Surgical treatment for strabismus is to promote binocular vision, and the study is to evaluate the effect of surgical realignment on near stereopsis in exotropic and esotropic patients.

METHODS

The records of patients who underwent strabismus surgery were retrospectively reviewed. Visual acuity, ocular deviations, fusion control, ocular motility, strabismus subtype and duration, surgery procedures, and stereopsis at before and at one month after surgery were collected. RMANOVA was performed to analyze stereopsis improvement by surgery. A logistic analysis was used to investigate the factors for stereopsis improvement.

RESULTS

143 exotropic and 40 esotropic patients were enrolled. The stereopsis was not significantly improved in patients with exotropia (p > .05), but not in esotropic patients (p < .01). Small degree of near deviation (β = 0.01), without vertical surgery (β = 0.11), and the high pre-surgery Titmus (β = -0.44) were related factors for stereopsis improvement in exotropia patients; male (β = 0.21) and the high pre-surgery Titmus (β = -0.36) were related factors for stereopsis improvement in esotropia patients.

CONCLUSION

The loss of stereopsis was significantly restored by surgery in esotropia patients and the extent of stereopsis recovery by surgery depends on the deviation at near distance, vertical surgery, and pre-surgery stereopsis in exotropes and on sex and pre-surgery Titmus in esotropes.

Lateral rectus muscle differentiation potential in paralytic esotropia patients

Purpose and background

Recently, we found that maximal medial rectus recession and lateral rectus resection in patients with complete lateral rectus paralysis resulted in a partial restoration of abduction. In an attempt to understand some of the mechanisms involved with this effect we examined gene expression profiles of lateral recti from these patients, with our focus being directed to genes related to myogenesis.

Materials and methods

Lateral recti resected from patients with complete lateral rectus paralysis and those from concomitant esotropia (controls) were collected. Differences in gene expression profiles between these two groups were examined using microarray analysis and quantitative Reverse-transcription PCR (qRT-PCR).

Results

A total of 3056 differentially expressed genes (DEGs) were identified between these two groups. Within the paralytic esotropia group, 2081 genes were up-regulated and 975 down-regulated. The results of RT-PCR revealed that PAX7, MYOG, PITX1, SIX1 and SIX4 showed higher levels of expression, while that of MYOD a lower level of expression within the paralytic esotropia group as compared with that in the control group (p < 0.05).

Conclusion

The decreased expression of MYOD in the paralytic esotropia group suggested that extraocular muscle satellite cell (EOMSCs) differentiation processes were inhibited. Whereas the high expression levels of PAX7, SIX1/4 and MYOG, suggested that the EOMSCs were showing an effective potential for differentiation. The stimulation resulting from muscle surgery may induce EOMSCs to differentiate and thus restore abduction function.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01994-4.

Surgical outcomes of acute acquired comitant esotropia of adulthood

Background

Acute acquired comitant esotropia (AACE) is a type of strabismus characterized by a sudden onset of large angle esotropia with diplopia, which often occurs in children after infancy, teenagers, and young adolescents. However, studies on the surgical outcomes of only adults are rare. The purpose of this article is to analyze the surgical outcomes for adult patients diagnosed with AACE.

Methods

Medical records of 24 patients who had undergone surgery for AACE were retrospectively analyzed. The main outcome measures were the final motor and sensory success rate after surgery and factors affecting motor and sensory outcomes. Motor success was considered alignment within 8 prism diopter (PD) at both near and distance and sensory success was stereoacuity ≥ 60 sec/arc.

Results

The preoperative mean esodeviation angles were 33.1 ± 10.4 PD at distance and 33.3 ± 11.2 PD at near. The mean period of postoperative follow up was 7.5 ± 4.5 months (range 1–8 months). The postoperative mean esodeviation angles at final follow-up time were 3.4 ± 6.1 PD at distance and 3.8 ± 6.7 PD at near. The surgical motor success rate at final follow-up was 79.2% (19/24). The sensory success rate at final follow-up was 50.0% (12/24). The factor affecting the motor outcome was the type of surgery (p < 0.05). The factor affecting sensory outcome was postoperative follow-up time (p < 0.05).

Conclusions

Surgery type appears to affect surgical motor outcomes in adults with AACE. Although the sensory outcome was favorable, it seems that regaining bifoveal fixation takes time.

Outcome of Esotropia Surgery in 2 Tertiary Hospitals in Cameroon

Purpose

To evaluate the ocular alignment following esotropia surgery in our setting.

Patients and Methods

We conducted a cross sectional descriptive study which spanned 19 years, from October 1999 to September 2018 at the Douala General Hospital and the Yaoundé Central Hospital. Complete medical records of patients who underwent surgery for esotropia during the study period were included. Data collected included age at diagnosis, sex, age of onset of esotropia, age at surgery, refractive error, type of surgery performed, pre and post-operative angle of deviation. The outcome was considered good when the postoperative angle was ≤10 prism diopters (PD).

Results

Four hundred and ninety patients with primary esotropia were seen during the study period. Only 155 returned for follow-up after wearing the full cycloplegic correction for a minimum period of 3 months. Accommodative esotropia was found in 32 cases (20.6%). Among the 123 cases requiring surgery, 63 cases underwent surgery (51.2%). Fifty-nine complete records were included (59.3% females and 40.7% males). The mean age at the time of diagnosis was 6.5 ± 6.1 years and the mean age at the time of surgery was 8.7 ± 6.1 years. The mean preoperative angle at distance was 42.8 ±10.8 PD. The outcome was good in 91.5% of cases. No factor influenced the outcome of surgery.

Conclusion

The outcome of esotropia surgery was good in this study. This could serve to increase patient motivation to accept surgery in our setting.

Long-term motor and sensory outcomes after surgery for the nonaccommodative component of partially refractive accommodative esotropia

PURPOSE

To report long-term motor and sensory outcomes after surgery for the nonaccommodative component of partially refractive accommodative esotropia (PRAET).

METHODS

The medical records of consecutive patients ≤11 years old operated for the nonaccommodative component of PRAET and followed postoperatively for at least 10 years were retrospectively reviewed.

RESULTS

A total of 47 patients were included (median age, 3.0 years). The mean postoperative follow-up was 12.15 ± 2.05 years (range, 10.00-17.50 years). Overall, 23 patients (49%) had surgical success; 10 (21%), decompensation; and 7 (15%), esotropia with a high ratio of accommodative convergence to accommodation (AC/A) or consecutive exotropia. The median age at surgery, mean cycloplegic refraction, median near and distance deviation, presence of binocular vision, and amblyopia did not predict decompensation, a high AC/A ratio esotropia, and consecutive exotropia. Eight patients (18%) achieved stereopsis. Patients with an older age at onset (2.87 ± 1.31 years) and a shorter duration of strabismus (≤4 years) achieved better stereopsis.

CONCLUSIONS

Nearly half of our patients with PRAET achieved a successful ocular alignment after surgery for the nonaccommodative component. Some developed decompensation, a high AC/A ratio esotropia, or consecutive exotropia. Few patients achieved stereopsis. Older age at onset and a shorter duration of strabismus predicted a better stereopsis outcome.

The difference of surgical outcomes between manifest exotropia and esotropia

PURPOSE

To determine the factors that affect ocular alignment and binocular sensory functions after strabismus surgery and compare surgical outcomes between manifest exotropia (XT) and esotropia (ET).

METHODS

In a retrospective study, 41 XT and 17 ET patients who had undergone strabismus surgery were recruited. Information on type and duration of strabismus, age at onset of deviation and surgery, pre- and postoperative strabismus deviation angles, and binocular sensory functions including stereoacuity and macular fusion capacity was recorded.

RESULTS

In all patients, the ocular alignment and binocular sensory functions improved with time following surgery. Residue strabismus deviation angles (≦ 10 prism diopters) at postoperative 1 month determined the final successful ocular alignment. In patients with final excellent binocular sensory functions, XT group restored macular fusion capacity and stereoacuity at postoperative 1 month, but ET group regained macular fusion capacity at postoperative 1 month and then restored stereoacuity at postoperative 3 months. Though XT patients showed better pre- and postoperative stereoacuity than ET patients, patients with successful ocular alignment had an odd of 4.5 in XT group and 22.5 in ET group to achieve excellent and fair binocular sensory functions.

CONCLUSION

Surgical correction of strabismus could improve ocular alignment and binocular sensory functions in patients with manifest strabismus, regardless of onset age, strabismus duration, or type. Postoperative 1-month status may help to predict the final motor and sensory outcomes. ET patients would benefit more final successful ocular alignment and excellent binocular sensory functions from early surgery and maintaining postoperative small deviation angle than XT patients.

Outcomes after the surgery for acquired nonaccommodative esotropia

Background

To analyze the surgical outcomes for patients diagnosed with acquired nonaccommodative esotropia (ANAET).

Methods

In this retrospective study, the medical records of 35 patients who had undergone the surgery for ANAET with a postoperative follow-up period of 6 months or more were reviewed. The main outcome measures were postoperative esodeviation angle, final success rate, and factors affecting surgical outcome. Surgical success was considered to be an alignment within 8 prism diopters (PD) at distance and near.

Results

The preoperative mean esodeviation angles were 37.3 ± 13.7 PD at distance and 38.6 ± 16.6 PD at near. The postoperative mean esodeviation angles at distance were as follows: 4.2 PD at day 1, 4.0 PD at month 1, 3.9 PD at month 3, 4.9 PD at month 6, 4.7 PD at year 1, and 4.8 PD at final follow-up. There was no statistically significant difference in angle of esodeviation between the initial postoperative period (day 1 to month 6) and the final follow-up day (p > 0.05). The surgical success rate at final follow-up was 65.7% (23/35). Among the 12 patients for whom the surgery failed, 9 (24.3%) showed esotropia and 3 (8.1%) exotropia of more than 8 PD. Six patients (16.2%) underwent reoperation (4 for esotropia and 2 for exotropia). There was no factor influencing surgical outcome (p > 0.05).

Conclusions

The surgical outcome in patients with ANAET was relatively favorable: the final success rate was 65.7% and the reoperation rate was 17.1%.

Preoperative Factors Affecting Stereopsis after Surgical Alignment of Acquired Partially Accommodative Esotropia

BACKGROUND/AIM

Despite successful ocular realignment, many strabismus patients never develop high levels of stereopsis. The purpose of this study was to determine preoperative factors that affect postoperative stereopsis in patients with acquired partially accommodative esotropia (APAET).

METHODS

This was a retrospective chart review of patients who underwent successful surgery for APAET. We compared preoperative factors between patients achieving postoperative stereopsis of 100 seconds of arc or better versus those with worse than 100 seconds of arc.

RESULTS

Fifty-seven patients met our inclusion criteria. Twenty-four (42%) had a final stereopsis of 100 seconds of arc or better. The mean age of onset of esodeviation for patients attaining stereopsis of 100 seconds of arc or better was 31.8 ± 12.9 months, versus 23.9 ± 10.0 months (p = 0.012) for patients with worse than 100 seconds of arc. Duration of constant misalignment was not significantly different between the two groups (30.1 ± 18.5 for patients attaining 100 seconds of arc versus 27.3 ± 18.6 months; p = 0.57). A multivariate regression analysis found older age of onset to be the only predictive factor for achieving better postoperative stereopsis (odds ratio 1.065, 95% CI: 1.014-1.118).

CONCLUSION

Age of onset appears to be the most important factor affecting postoperative stereopsis in patients with APAET. Patients with an age of onset after 36 months tended to have better outcomes regardless of the duration of misalignment. Duration of misalignment and age at surgery did not have a significant impact on postoperative stereopsis in our patient population.