The effects of topical cycloplegics in acute acquired comitant esotropia induced by excessive digital device usage

Factors affecting outcome of acquired comitant esotropia with restricted use of digital devices: ACEDD Study 3

OBJECTIVE

The objective of this study is to investigate factors associated with outcomes after 3 months of instructed usage of hand-held digital devices (DD) in patients with acquired comitant esotropia (ACE).

METHODS AND ANALYSIS

This prospective multicentre observational study included patients with ACE, aged 5-35 years, who used DD within 1 year of onset and were followed up for clinical findings and instructed use of DD. The outcomes were classified into four groups: cured, improved, unchanged and worsened. After the analysis of group differences in the clinical and DD use-related factors by univariate analysis, we used ordinal logistic regression models to identify factors associated with favourable outcomes.

RESULTS

Of 156 patients (mean age (SD): 16.4 (7.4) years), 10 (6%), 58 (37%), 67 (43%) and 21 (14%) were classified into the cured, improved, unchanged, and worsened, respectively. In the univariate analysis, consultation within 3 months of onset, small-angle strabismus at distance and good stereoacuity were associated with good outcomes. Ordinal logistic regression analysis on adjusting for age with stereoacuity or successful DD-use time halving showed that small-angle strabismus at distance (OR: 1.02, 95% CI 1.00 to 1.03, p=0.023), good stereoacuity (OR: 1.31; 95% CI 1.10 to 1.56; p=0.003) and successful halving of DD-use time (OR: 0.63; 95% CI 0.43 to 0.92; p=0.016) influenced favourable outcomes.

CONCLUSION

Patients with small-angle esotropia, good stereoacuity on consultation and success in halving DD-use time had a higher chance of recovery through instructional DD usage. Further studies using objectively measurable systems are needed to ensure the accuracy of DD-use time.

Comprehensive analysis of strabismus reoperations: clinical insights and progression factors

BACKGROUND

To compare and analyze clinical characteristics of patients undergoing two surgeries and multiple surgeries and explore relevant factors to lay the foundation for clinical prediction.

METHODS

A retrospective analysis was conducted on clinical data from all patients who underwent twice and multiple strabismus surgeries at Tianjin Eye Hospital between October 2012 and September 2021. Patients were divided into Group A (two surgeries) and Group B (more than two surgeries) based on the cumulative number of surgeries performed. Clinical details at the first recurrence, including sex, age, native place, overall medical history, onset time, visual acuity, affected muscle(s), etc., were documented. Non-parametric tests and chi-square tests were used to analyze clinical characteristics in each group. Binary and ordered logistic regression analysis assessed parameters associated with multiple reoperations. A linear mixed-term model observed factors impacting affected muscle(s) during surgery. Researchers examined clinical traits related to secondary strabismus variables.

RESULTS

Among the 910 included patients, 840 required two surgeries (Group A) and 70 underwent more than two surgeries (Group B). Significant differences were found in age, onset time, interval time, and secondary factors. Regression analysis highlighted the significant impact of interval time on the reoperation rate, effectively predicting outcomes in patients with concomitant strabismus. Other ophthalmoplegia and secondary factors significantly influenced reoperation rates in patients with non-concomitant strabismus. Interval time, esotropia, and exotropia were linked to concomitant secondary strabismus patients, while the number of surgeries, DVD, esotropia, exotropia, and esotropia V-pattern were associated with non-concomitant secondary strabismus patients. In a longitudinal study, patients with multiple surgeries showed a correlation between the vertical deviation angle magnitude and the number of involved extraocular muscles. Regression analysis revealed that in patients with concomitant strabismus, interval time, exotropia, and esotropia influenced the total number of muscles during surgery. For patients with non-concomitant strabismus, interval time, secondary factors, and SOP impacted the total number of muscles during surgery.

CONCLUSIONS

Interval time in patients with concomitant strabismus, as well as secondary and other ophthalmoplegia in non-concomitant strabismus, are the main factors for multiple reoperations.

Effects of cycloplegia on crystalline lens morphology and location in acute acquired concomitant esotropia

PURPOSE

The study aims to compare morphology and location of crystalline lens between acute acquired concomitant esotropia (AACE) patients and control subjects, both before and after cycloplegia.

METHODS

This is a prospective and observational clinical study. Morphological and locational parameters of the crystalline lens in 53 AACE patients and 32 control subjects were assessed before and after cycloplegia using CASIA2 system, which represents the latest swept-source anterior segment optical coherence tomography. Cycloplegic refraction was recorded by administering 1% atropine in patients younger than 12 years and 1% cyclopentolate in those > 12 years old. Morphological parameters included anterior radius of curvature (ARC), posterior radius of curvature (PRC), lens thickness (LTH), and equivalent diameter of lens (LED). Locational parameters comprised lens decentration (LD) and lens tilt (LT). Comparison of these parameters before and after cycloplegia were conducted between AACE and controls. Additionally, the study analyzed and compared the changes in these parameter post-cycloplegia.

RESULTS

Our findings suggest no significant difference in morphological parameters including ARC, PRC, LTH and LED between AACE patients and controls before or after cycloplegia. However, 2D-modeling data in the 0° meridian revealed that variation post-cycloplegia of LD (lens shift) in right eyes was different in AACE patients, measuring - 0.03(0.08) [median(interquartile range)] which was significantly distinct from the control group, exhibiting a measurement of 0.01(0.06) (z =  - 2.373, p = 0.018). In left eyes, a similar trend was observed with lens shift in the 0° meridian being 0.02(0.06) in AACE, significantly differing from control group's measurement of - 0.02(0.08) (z =  - 2.809, p = 0.005). Further, correlation analysis revealed that larger temporal shift of lens was associated with greater changes in ARC (r = 0.294, p = 0.006) and LTH (r =  - 0.230, p = 0.031).

CONCLUSIONS

The morphological features of the crystalline lens were similar in AACE patients and controls; however, the change of lens location by cycloplegia was observed only in AACE patients, suggesting an association with excessive accommodation.

Medial rectus insertion site in cases of acute acquired comitant esotropia associated with excessive digital device usage

PURPOSE

To compare the distance of the medial rectus muscle insertion to the limbus (DMIL) between patients with acute acquired comitant esotropia (AACE) associated with excessive digital device usage (EDDU) and exotropic patients.

STUDY DESIGN

Retrospective study.

METHODS

The medical records of 72 eyes of 44 patients with EDDU were retrospectively analyzed. The DMIL was measured from the anterior part at the midpoint of the medial rectus muscle insertion into the anterior limbus using a caliper after dissecting the medial rectus muscle with two control sutures at 12 o'clock and 6 o'clock. The DMIL in the non-fixation eye was compared between 44 patients with AACE and 23 patients with exotropia.

RESULTS

The mean daily EDDU was 6.5 ± 3.1 h. The mean cycloplegic refractive errors (spherical equivalent: SE) were - 3.18 ± 2.52 diopters (D) OD and - 3.03 ± 2.42 D OS. The mean DMIL in the 72 eyes of 44 patients with AACE associated with EDDU was 4.30 ± 0.66 mm. The difference in DMIL of non-fixation eyes between 44 AACE patients and 23 exotropic patients was significant (4.28 ± 0.65 mm vs. 5.28 ± 0.50 mm, p < 0.0001). However, the SE in 44 non-dominant eyes of AACE was - 3.08 ± 2.56 D, significantly stronger than - 1.22 ± 1.93 D in the 23 exotropic eyes (p = 0.008).

CONCLUSION

DMIL in patients with AACE associated with EDDU was significantly shorter. This anatomical anomaly may be an etiology of AACE associated with EDDU.

Advances in the diagnosis and treatment of acute acquired comitant esotropia

Acute acquired comitant esotropia (AACE) is mainly characterized by sudden onset, accompanied by diplopia, without extraocular muscles paralysis or ocular motility disorders. In recent years, the incidence of AACE has been increasing, researchers have found that this phenomenon may be related to the widespread use of electronic devices and the increase in the number of people working from home during the COVID-19 pandemic. However, its neural mechanisms have not been fully elucidated. This article primarily reviews the latest developments in the diagnosis and treatment of AACE from the perspectives of etiology and treatment methods, aiming to provide direction for future in-depth exploration of the pathogenesis and treatment approaches of this disease.

Botulinum toxin type A in treating early-stage patients with small-angle acute acquired comitant esotropia

AIM

To investigate botulinum toxin A (BTXA) efficacy on small-angle (≤25Δ) acute acquired concomitant esotropia (AACE) in early-stage patients.

METHODS

The electronic medical record data of AACE patients during March 2019 and June 2023 were collected in this retrospective and hospital-based cohort study. A total of 72 small-angle AACE patients received BTXA extraocular muscle injection. Patients were grouped by onset-to-treatment time (Group A: ≤6mo, Group B: >6mo). Deviation of esotropia, eye alignment and stereopsis were analyzed at the period of pre/post-injection (1wk, 1, 3, and 6mo). Orthophoria rate at 6mo (horizontal deviation <10Δ and binocular single vision) were considered as outcome index.

RESULTS

There were no significant baseline differences (P>0.05) between two groups except onset-to-treatment time (2mo vs 11mo, P<0.001). Higher orthophoria rates were in Group A at last follow-up (94.74% vs 73.53%, P=0.013). Post-BTXA deviations of two groups at 1mo showed no difference (P>0.05); while in 3 and 6mo Group A was significantly smaller than group B (all P<0.001). No statistically significant differences were observed among all post-BTXA deviations of near and distance in Group A. In Group B, deviation at 3mo (near: 2Δ vs 0, P<0.001; distance: 4Δ vs 0, P<0.001) and 6mo (near: 6Δ vs 0, P<0.001; distance: 6Δ vs 0, P<0.001) was significant increased compared to deviation at 1wk after treatment. Group A showed better stereopsis recovery in last follow-up compared to Group B (80″ vs 200″, P=0.002). Both groups obtained improved stereopsis after treatment (Group A: 80″ vs 300″, P<0.001; Group B: 200″ vs 300″, P=0.037).

CONCLUSION

BTXA is effective for AACE with small deviation (≤25Δ) in early stage. Delayed treatment (>6mo) may reduce BTXA efficacy. Early BTXA intervention benefits long-term eye alignment and stereopsis recovery.

Conformation of Horizontal Extraocular Muscle Insertions in Acute Acquired Concomitant Esotropia Induced by Excessive Digital Device Usage

Purpose

Acute acquired concomitant esotropia induced by excessive digital device usage, especially smartphones (SAACE), has been increasing over the past few years. Convergence spasm induced by excessive near work has been suggested as a mechanism. Anatomical differences could also potentially contribute to SAACE onset. The present study investigated the conformation of horizontal recti between SAACE patients and normal subjects.

Patients and Methods

In 15 SAACE patients (SAACE group), the distances between the limbus and insertion of the horizontal recti (LI distance) and the widths of horizontal recti on the insertion (insertion width) were measured. The control group consisted of 30 patients who underwent retinal detachment surgery. Differences in LI distances and insertion widths were compared between SAACE and control groups.

Results

While there were no differences between the two groups for LI distances and insertion widths of lateral recti, there were significantly shorter LI distances for the medial recti in the SAACE group (P<0.05). Moreover, the SAACE group tended to exhibit larger insertion widths of the medial recti. Medial/lateral ratio of LI distances were significantly lower and insertion widths were significantly higher in the SAACE compared to the control group (P<0.05).

Conclusion

Based on the observations of more anterior insertion and larger muscle widths, this suggests there are stronger forces of medial recti in SAACE. In addition to excessive accommodation followed by increases in medial recti tonus, the results also suggest that an anatomical imbalance between lateral and medial recti contributes to esotropia onset following excessive near work.