Deficits of Visual Cortex Function in Acute Acquired Concomitant Esotropia Patients

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.

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.