Longitudinal changes in binocular coordination of smooth pursuit in patients with intermittent exotropia after strabismus surgery

Comparative Analysis of Strabismus Measurement Using a Video Oculagraphy System and Alternate Prism Cover Test

PURPOSE

The aim of the study was to compare distance vision measurements obtained with video oculography (VOG) and an alternate prism cover test (APCT).

DESIGN

Single-center, retrospective, and cross-sectional.

METHODS

Eighty-seven subjects with strabismus were included. All patients underwent an optometric examination. The measurement of strabismus in distance vision was performed with the best optical correction using the APCT and the VOG GazeLab. Subjects were divided according to the type of strabismus; 41 were esotropic and 46 were exotropic.

RESULTS

The general comparison of APCT and VOG showed a mean difference of 0.60±2.74 prism diopters (Δ), not observing statistical differences between both methods ( P =0.059) and presenting a correlation of 0.976 ( P <0.001). Using APCT, the mean amount of esotropia for the group was 18.31±11.64 Δ and that of exotropia was 19.62±8.80 Δ. Compared with the VOG, the mean value of esotropia for the group was 18.65±11.65 Δ and that of exotropia was 19.48±8.62 Δ. The means are statistically different for the esotropia group ( P =0.005) but not for the exotropia group ( P =0.318). There was a high direct correlation between the methods of measurement for both the esotropic ( R =0.980; P <0.001) and exotropic patients ( R =0.975; P <0.001). Bland-Altman analysis shows a mean difference of 1.37±2.76 Δ for the esotropia patients and 0.31±2.66 Δ for the exotropic patients, respectively.

CONCLUSIONS

This study demonstrated comparable results in measuring strabismus between VOG and APTC for esotropia and exotropia, with an excellent correlation between both methods and good agreement, especially in subjects with exotropia.

Hypertelorbitism Corrected by Facial Bipartition Improves Exotropia

BACKGROUND

The purpose of this study was to detail perioperative ophthalmologic evaluations to characterize functional ocular outcomes after facial bipartition surgery.

METHODS

Patients with hypertelorbitism who underwent facial bipartition surgery were studied specifically for eye motility disorders by separating patients into rare craniofacial clefts (midline and paramedian) (n = 34) and craniofacial dysostosis (Apert, Crouzon, and Pfeiffer) (n = 74). Preoperative and postoperative (12 months) ophthalmologic examinations (with depth perception tests), computed tomography scans, and magnetic resonance imaging scans were analyzed.

RESULTS

Among craniofacial cleft patients, mean interdacryon distance was reduced from 39 ± 4 mm to 17 ± 2 mm, with strabismus improved from 88 percent (exotropia 82 percent) preoperatively to only 29 percent postoperatively. Depth perception improved to a lesser degree, with abnormal tests at a rate of 79 percent preoperatively to 56 percent postoperatively. Wider hypertelorbitism had a higher degree of strabismus. Among craniofacial dysostotic patients, mean interdacryon distance was reduced from 37 ± 3 mm to 17 ± 2 mm, and strabismus improved from 55 percent to only 14 percent. Depth perception improved to a lesser degree, with 68 percent abnormal tests preoperatively and 46 percent postoperatively. Apert patients had more V-pattern strabismus and exotropia (79 percent) than did other craniofacial dysostosis patients (42 percent).

CONCLUSIONS

The authors' data indicate that facial bipartition for hypertelorbitism-known to improve periorbital aesthetics-also improves eye motility disturbances. Thus, vision problems related to exotropia should be considered a functional indication for facial bipartition surgery in patients with hypertelorbitism.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Study on Binocular Accommodative Function in Children With Different Types of Intermittent Exotropia

Objective: This study aims to investigate the monocular and binocular accommodative amplitude (AMP) and accommodative function (AF) in children with different types of intermittent exotropia (IXT). Methods: A total of 40 children with IXT were enrolled in the study. Monocular and binocular AMP and AF were measured using the modified approach method and the ±2D flip method, and the differences between the fixing and non-fixing eyes of non-strabismic children and children with different types of IXT were compared. Results: The AMP of the fixing eyes of children with IXT was lower than that of their non-fixing eyes (p = 0.007). Conversely, the AF was higher in the fixing eyes than in the non-fixing eyes (p < 0.001). The AMPs of each group of children with IXT were lower than those of the control group, while the AMP of the group with convergence insufficiency was lower than that of the other two groups with IXT. In addition, the AF of the group with convergence insufficiency was lower than that of the group with basic exotropia and the control group (p < 0.05). Conclusion: There is a difference in accommodation between the fixing and non-fixing eyes of children with IXT, and the degree of variation depends on the type of IXT. Moreover, the binocular accommodative function of children with IXT is lower than that of non-strabismic children.