Strabismus management in retinoblastoma survivors.

PURPOSE: To report the result of strabismus surgery in eye-salvaged retinoblastoma (Rb) patients. METHODS: A retrospective case series including 18 patients with Rb and strabismus who underwent strabismus surgery after completing tumor treatment by a single pediatric ophthalmologist. RESULTS: A total of 18 patients (10 females and 8 males) were included with a mean age of 13.3 ± 3.0 (range, 2-39) months at the time tumor presentation and 6.0 ± 1.5 (range, 4-9) years at the time of strabismus surgery. Ten (56%) patients had unilateral and 8(44%) had bilateral involvement and the most common worse eye tumor's group was D (n = 11), C (n = 4), B (n = 2) and E (n = 1). Macula was involved by the tumors in 12 (67%) patients. The tumors were managed by intravenous chemotherapy (n = 8, 47%), intra-arterial chemotherapy (n = 7, 41%) and both (n = 3, 17%). After complete treatment, the average time to strabismus surgery was 29.9 ± 20.5 (range, 12-84) months. Except for one, visual acuity was equal or less than 1.0 logMAR (≤ 20/200) in the affected eye. Seven (39%) patients had exotropia, 11(61%) had esotropia (P = 0.346) and vertical deviation was found in 8 (48%) cases. The angle of deviation was 42.0 ± 10.4 (range, 30-60) prism diopter (PD) for esotropic and 35.7 ± 7.9 (range, 25-50) PD for exotropic patients (P = 0.32) that after surgery significantly decreased to 8.5 ± 5.3 PD in esotropic cases and 5.9 ± 6.7 PD in exotropic cases (P < 0.001). The mean follow-up after surgery was 15.2 ± 2.0 (range, 10-24) months, in which, 3 (17%) patients needed a second surgery. CONCLUSION: Strabismus surgery in treated Rb is safe and results of the surgeries are acceptable and close to the general population. There was not associated with tumor recurrence or metastasis.

Parental perspectives and concerns regarding exotropia surgery and comparison with clinicians' predictions.

PURPOSE: To evaluate parental perspectives and concerns regarding exotropia surgery and compare them with clinicians' predictions of parental responses in Korean pediatric patients with intermittent exotropia. METHODS: This survey study included the parents of pediatric patients with intermittent exotropia who underwent surgery and clinicians at five hospitals from June 2022 to February 2023, who participated in the Survey of Parental Attitude and Concerns of Exotropia surgery (SPACE) study 1. Parental attitudes and concern about exotropia surgery were assessed using a questionnaire. Clinicians' estimation of each item corresponding to the parental questionnaire was also assessed and compared with parental responses. RESULTS: A total of 266 parents and 41 clinicians were included. More parents responded that information about surgery was most helpful or most commonly received from clinicians than clinicians estimated (P = 0.001). More parents reported actively communicating with the child about surgery than clinicians estimated (P < 0.001). Parents showed a higher level of concern for general anesthesia and the hospital environment than clinicians thought they would (P = 0.002 and P < 0.001, resp.). In the postoperative follow-up items, parents showed high levels of concern regarding postoperative infection (P < 0.001), conjunctival redness (P = 0.040), persistent overcorrection (P < 0.001), and glasses wearing (P = 0.019). CONCLUSIONS: Parental perspectives and concerns regarding pediatric intermittent exotropia surgery differed from clinicians' estimations thereof. More parents obtain information on exotropia surgery from clinicians and actively talk about surgery with their child than estimated by clinicians. Parents had a higher level of concern regarding general anesthesia, hospital environment, postoperative infection, conjunctival redness, persistent overcorrection, and glasses wearing compared with clinician estimations.

Surgical management of oculomotor nerve palsy: a comparison of lateral rectus deactivation combined with either medial rectus resection or medial rectus fixation to the medial palpebral ligament.

PURPOSE: To analyze and compare the outcome of two different surgical procedures in patients with complete oculomotor nerve palsy with large-angle exotropia. METHODS: The medical records of patients with total oculomotor nerve palsy and large-angle exotropia operated on at a single center from January 2006 to June 2020 were reviewed retrospectively. One group underwent lateral rectus deactivation with medial rectus resection (resection group); the other group underwent lateral rectus deactivation with medial rectus fixation to the medial palpebral ligament (fixation group). Surgical outcomes on the first postoperative day and at 6 months postoperatively were analyzed, including alignment and postoperative complications. All statistical analyses were performed using STATA version 14. A P value of <0.05 was considered significant. RESULTS: A total of 35 patients were included. There was a trend toward greater surgical success in the fixation group (93%) than in the resection group (65%), but these results were not statistically significant. Postoperative exotropic drifts were noted in both the procedures but tended to be more with patients in the resection group. Postoperative complications were noted only in the fixation group. CONCLUSIONS: Lateral rectus deactivation with medial rectus fixation to the medial palpebral ligament requires more time and greater surgical expertise but appears to better prevent postoperative exotropic drift compared with lateral rectus deactivation combined with medial rectus resection.

Six-month binocular stereopsis recovery and its influencing factors in children with intermittent exotropia.

OBJECTIVE: To investigate the recovery of binocular stereopsis recovery and its influencing factors in children with intermittent exotropia after successful correction of eye position. METHODS: Prospective clinical study. A total of 178 patients, aged 9 ∼ 14 (10.8 ± 1.7) years, who were successfully corrected after intermittent exotropia surgery at the Beijing Tongren Hospital Affiliated to Capital Medical University from October 2023 to September 2023 were collected, the follow-up duration was six-month or longer. Paired t test, Pearson correlation analysis and multivariable linear regression analysis were used to probe preoperative clinical features that may predict the stereopsis six months after surgery. RESULTS: Six months after surgery, the angle of deviation of the patients met the orthotopic standard, and there was significant difference compared with that before surgery (distant: -2.7△±3.2△ vs. -30.5△±8.4△, t=-25.3, P < 0.001. Near:-3.7△±4.1△ vs. -33.7△±8.0△, t=-26.1, P < 0.001). Distant stereopsis (3.0 ± 0.6 vs. 3.9 ± 0.4, t = 4.9, P < 0.05) and near stereopsis (2.3 ± 0.5 vs. 2.6 ± 0.4, t = 3.8, P < 0.05) were both significantly improved compared with that of before surgery. 17% and 22% patients rebuilt normal distant stereopsis and normal near stereopsis, respectively. Preoperative distant stereopsis (r=-0.26, P = 0.004) and near stereopsis (r=-0.23, P = 0.011) was significantly negatively correlated with convergence reserve. Multivariable analysis showed that patients' age (ß = 0.003, p = 0.037), anisometropia (ß = 0.015, p = 0.043), and preoperative distant stereopsis (ß = 0.456, p < 0.001) were significantly associated with postoperative distant stereopsis. Patients' age (ß = 0.005, p = 0.044), anisometropia (ß = 0.127, p = 0.034), angle of deviation (ß=-0.230, p = 0.020), and preoperative near stereopsis (ß = 0.136, p < 0.001) were significantly associated with postoperative near stereopsis. CONCLUSION: IXT patients could get eye position fixed after surgery, about 20% patients benefited from stereopsis improvement. Patient's age, binocular anisometropia, angle of deviation and preoperative stereopsis were independent factors influencing postoperative stereopsis.

The causal effect of obesity on concomitant exotropia: A lifecourse Mendelian randomization study.

Obesity is now a significant global public health issue. Limited understanding exists regarding the association between obesity and concomitant exotropia. Our objective was to identify the causal relationship between lifecourse obesity, including birth weight, childhood body mass index (BMI), and adult BMI, and the risk of concomitant exotropia. We used a two-sample Mendelian randomization (MR) strategy to examine the causal relationship with inverse-variance weighted method as the primary MR analysis. We carried out sensitivity analyses to evaluate the accuracy and robustness of our findings. Also, we performed reverse-direction MR analysis to eliminate the possibility of reverse causality. Childhood BMI, as opposed to birth weight or adult BMI, had a significant impact on the risk of concomitant exotropia (odds ratio = 1.40, 95% confidence interval (CI): 1.08-1.81, P = .01). This significance persisted even after accounting for birth weight and adult BMI using multivariable MR analysis (odds ratio = 1.35, 95% CI: 1.04-1.75, P = .02). There was no significant heterogeneity or pleiotropy observed in sensitivity analyses (P > .05). Multivariable MR analysis further confirmed the absence of pleiotropic effects of some risk factors including prematurity, maternal smoking around birth and refractive error. Reverse causality did not affect the causal relationship (beta = -0.0244, 95% CI: -0.0545 to 0.0056, P = .11). Genetic predisposition to higher childhood BMI was found to be causally linked to an increased risk of concomitant exotropia.

Presence of Copy Number Variants Associated With Esotropia in Patients With Exotropia.

Importance: Strabismus is a common ocular disorder of childhood. There is a clear genetic component to strabismus, but it is not known if esotropia and exotropia share genetic risk factors. Objective: To determine whether genetic duplications associated with esotropia are also associated with exotropia. Design, Setting, and Participants: This was a cross-sectional study conducted from November 2005 to December 2023. Individuals with constant or intermittent exotropia of any magnitude or a history of surgery for exotropia were recruited from pediatric ophthalmic practices. Data were analyzed from March to December 2023. Exposure: Genetic duplication. Main Outcomes and Measures: Presence of genetic duplications at 2p11.2, 4p15.2, and 10q11.22 assessed by digital droplet polymerase chain reaction. Orthoptic measurements and history of strabismus surgery were performed. Results: A total of 234 individuals (mean [SD] age, 19.5 [19.0] years; 127 female [54.3%]) were included in this study. The chromosome 2 duplication was present in 1.7% of patients with exotropia (4 of 234; P = .40), a similar proportion to the 1.4% of patients with esotropia (23 of 1614) in whom it was previously reported and higher than the 0.1% of controls (4 of 3922) previously reported (difference, 1.6%; 95% CI, 0%-3.3%; P < .001). The chromosome 4 duplication was present in 3.0% of patients with exotropia (7 of 234; P = .10), a similar proportion to the 1.7% of patients with esotropia (27 of 1614) and higher than the 0.2% of controls (6 of 3922) in whom it was previously reported (difference, 2.8%; 95% CI, 0.6%-5.0%; P < .001). The chromosome 10 duplication was present in 6.0% of patients with exotropia (14 of 234; P = .08), a similar proportion to the 4% of patients with esotropia (64 of 1614) and higher than the 0.4% of controls (18 of 3922) in whom it was previously reported (difference, 5.6%; 95% CI, 2.5%-8.6%; P < .001). Individuals with a duplication had higher mean (SD) magnitude of deviation (31 [13] vs 22 [14] prism diopters [PD]; difference, 9 PD; 95% CI, 1-16 PD; P = .03), were more likely to have constant (vs intermittent) exotropia (70% vs 29%; difference, 41%; 95% CI, 20.8%-61.2%; P < .001), and had a higher rate of exotropia surgery than those without a duplication (58% vs 34%; difference, 24%; 95% CI, 3%-44%; P = .02). Conclusions and Relevance: In this cross-sectional study, results suggest that the genetic duplications on chromosomes 2, 4, and 10 were risk factors for exotropia as well as esotropia. These findings support the possibility that esotropia and exotropia have shared genetic risk factors. Whether esotropia or exotropia develops in the presence of these duplications may be influenced by other shared or independent genetic variants or by environmental factors.

Comparison of retinal nerve fiber layer thickness between monocular and alternating exotropia in patients with intermittent exotropia.

PURPOSE: To investigate differences in intraocular structure based on the presence or absence of fixation preference in children with intermittent exotropia (IXT) by comparing the thickness of the retinal nerve fiber layer (RNFL). METHODS: From October 2018 to March 2022, RNFL thickness was retrospectively analyzed using spectral domain optical coherence tomography. Participants had uncorrected visual acuity of 20/20, refractive errors close to emmetropia, and no anisometropia. The patients were divided into monocular and alternating exotropia groups through a cover-uncover test. The average and sectoral thickness of the RNFL in both groups were compared. RESULTS: The average global thickness and average thickness of each of the six sectors of the RNFL did not significantly differ between dominant and non-dominant eyes in the monocular exotropia group and between right and left eyes in the alternating exotropia group. The thickness did not significantly differ between the monocular exotropia group and the right or left eye of the alternating exotropia group. Interocular differences in RNFL thickness were negative in the monocular exotropia group (dominant eye-non-dominant eye) and positive in the alternating exotropia group (right eye-left eye) for the average, inferonasal, and inferior sectors, exhibiting statistically significant between-group differences (p = 0.019, p = 0.003, p = 0.023, respectively). CONCLUSIONS: In children with IXT without obvious refractive error, there was a significant interocular difference in RNFL thickness of the average, inferonasal, and inferior sectors between monocular and alternating exotropia groups. The presence of fixation preference may affect RNFL thickness.

Pearls & Oy-sters: Ocular Myasthenia Gravis: Central Ocular Motor Signs and Unilateral Visual Loss Caused by the Great Neuro-Ophthalmologic Impersonator.

Myasthenia gravis (MG) has been described as a great mimicker of other neurologic and ocular motility disorders, including centrally mediated ophthalmoplegia. For example, ocular myasthenia gravis (ocular MG) may cause impaired binocular visual acuity for near vision due to reduced accommodation or for distance vision due to accommodative excess. Notably, accommodative excess due to ocular MG is rare, but may occur with exotropia, with or without diplopia. We report 2 cases of ocular MG: First, a 32-year-old man with exotropia, bilateral hypometric and slowed adducting saccades with dissociated abducting nystagmus, miosis, and decreased distance vision in his right eye; second, a 45-year-old man with similar ocular motor deficits, miosis, and myopia. Both patients showed ocular motor deficits which appeared to localize to the pons but were instead due to ocular MG. Ocular MG should be considered in patients who present with reduced visual acuities due to any disruption in accommodation. Any ocular motor deficit, even if appearing to be centrally mediated or occurring without ptosis, may be caused by ocular MG.

Diagnostic Importance of OCT Pachymetry in Keratoconus.

AIMS: To demonstrate changes in distance and near fusional vergence measured with prism bars, while compensating for present heterophoria using current ametropia correction. In addition, to determine the differences in values of the AC/A ratio determined by the heterophoric (calculation) and gradient methods. MATERIAL AND METHODS: The basic sample includes 19 subjects with a mean age of 21.5 ±3.0 years (min. 18, max. 27). We used the Von Graefe technique for examination of distance and near phoria, and prism bars for examination of fusion vergences measured in prism diopters. We divided the basic cohort into six research sets according to the size of distance and near heterophoria. This was a cohort of patients with distance (D OR) and near orthophoria (N OR), a cohort of patients with distance (D EX) and near exophoria (N EX) and a set of patients with distance (D ES) and near esophoria (N ES). RESULTS: In the case of both groups with exophoria (distance, near) we found a statistically significant result only for negative fusion vergence (NFV). There was a statistically significant increase in NFV in the sample with distance and near exophoria (D EX, p = 0.01 and B EX, p = 0.02, respectively). In our study, we also demonstrated a statistically significant difference (p < 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method. CONCLUSION: By comparing fusion vergence values in patients with exophoria and orthophoria, we demonstrated that in the presence of distance or near exophoria there is an increase in ipsilateral fusion vergence. In the case of an increase in ipsilateral fusion vergence, the finding was statistically significant both distance and near (p = 0.01 and p = 0.02, respectively). By contrast, we were unable to prove this fact in the group of patients with esophoria. In our study, we also demonstrated a statistically significant difference (p < 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method.

The Effect of Heterophoria on the Size of Distance and Near Fusion Vergence.

AIMS: To demonstrate changes in distance and near fusional vergence measured with prism bars, while compensating for present heterophoria using current ametropia correction. In addition, to determine the differences in values of the AC/A ratio determined by the heterophoric (calculation) and gradient methods. MATERIAL AND METHODS: The basic sample includes 19 subjects with a mean age of 21.5 ±3.0 years (min. 18, max. 27). We used the Von Graefe technique for examination of distance and near phoria, and prism bars for examination of fusion vergences measured in prism diopters. We divided the basic cohort into six research sets according to the size of distance and near heterophoria. This was a cohort of patients with distance (D OR) and near orthophoria (N OR), a cohort of patients with distance (D EX) and near exophoria (N EX) and a set of patients with distance (D ES) and near esophoria (N ES). RESULTS: In the case of both groups with exophoria (distance, near) we found a statistically significant result only for negative fusion vergence (NFV). There was a statistically significant increase in NFV in the sample with distance and near exophoria (D EX, p = 0.01 and B EX, p = 0.02, respectively). In our study, we also demonstrated a statistically significant difference (p < 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method. CONCLUSION: By comparing fusion vergence values in patients with exophoria and orthophoria, we demonstrated that in the presence of distance or near exophoria there is an increase in ipsilateral fusion vergence. In the case of an increase in ipsilateral fusion vergence, the finding was statistically significant both distance and near (p = 0.01 and p = 0.02, respectively). By contrast, we were unable to prove this fact in the group of patients with esophoria. In our study, we also demonstrated a statistically significant difference (p < 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method.

Changes in ocular extorsion after horizontal muscle surgery in patients with intermittent exotropia coexisting with hypertropia and mild inferior oblique overaction.

PURPOSE: To investigate changes in vertical strabismus and extorsion in patients with intermittent exotropia and mild unilateral inferior oblique muscle overaction (IOOA) who underwent horizontal muscle surgery without vertical or oblique muscle surgery. METHODS: The medical records of 41 patients were retrospectively analyzed. The patients were followed up for at least 6 months after surgery. Fundus photography was performed before and after surgery, and the sum of the angles of torsion in both eyes was used to measure changes in extorsion using ImageJ software. The enrolled patients were divided into two groups according to the degree of IOOA: patients with grade 1 IOOA were placed in +1 IOOA group and those with grade 2 IOOA in +2 IOOA group. The pre- and postoperative angles of horizontal and vertical strabismus and extorsion were compared between the two groups. RESULTS: The +1 IOOA and +2 IOOA groups included 24 and 17 patients, respectively. The angle of preoperative exotropia did not differ significantly: 25.54 ± 5.68 prism diopters (PD) and 25.65 ± 8.11 PD in the +1 IOOA and +2 IOOA groups, respectively. In the +1 IOOA and +2 IOOA groups, hypertropia was 2.67 ± 1.52 PD and 2.82 ± 1.13 PD, respectively, and extorsion angles were 7.14 ± 2.77° and 7.94 ± 2.87°, respectively. As the IOOA degree increased, the extent of hypertropia and extorsion also increased. However, there were no significant differences between the two groups. Postoperative angles of hypertropia and extorsion significantly decreased in both groups (p < 0.001) after surgery. The degree of change in hypertropia and extorsion was not significantly different between the two groups (p = 0.563 and p = 0.354, respectively). CONCLUSIONS: Hypertropia and extorsion improved significantly after horizontal muscle surgery in patients with mild unilateral IOOA and intermittent exotropia. There was no significant difference in the improvement in hypertropia or extorsion between IOOA grades I and II.

The distribution characteristics of strabismus surgery types in a tertiary hospital in the Central Plains region during the COVID-19 epidemic.

OBJECTIVE: This study aimed to analyze the distribution of different types of strabismus surgery in a tertiary hospital in Central China during the three-year period of the COVID-19 pandemic. METHODS: A retrospective analysis was conducted on the clinical data of strabismus patients who underwent surgery and were admitted to the Department of Strabismus and Pediatric Ophthalmology at the First Affiliated Hospital of Zhengzhou University between January 2020 and December 2022. RESULTS: A total of 3939 strabismus surgery patients were collected, including 1357 in 2020, 1451 in 2021, and 1131 in 2022. The number of surgeries decreased significantly in February 2020, August 2021, and November and December 2022. Patients aged 0-6 years accounted for 37% of the total number of strabismus surgery patientsr. The majority (60%) of all strabismus surgery patients were diagnosed with exotropia, with intermittent exotropia accounting for the highest proportion (53%). There was no statistically significant difference in the proportion of intermittent exotropia and constant exotropia during the three-year period (χ2 = 2.642, P = 0.267 and χ2 = 3.012, P = 0.221, respectively). Among patients with intermittent exotropia, insufficient convergence type was the most common form of strabismus (accounting for over 70%). Non-accommodative esotropia accounted for more than 50% of all internal strabismus cases. CONCLUSION: During the period from 2020 to 2022, the total number of strabismus surgeries in our hospital did not show significant fluctuations, but there was a noticeable decrease in the number of surgeries during months affected by the pandemic. Exotropia accounted for the highest proportion among strabismus surgery patients. Intermittent exotropia was the most common type among patients undergoing surgery for exotropia, and the most prevalent subtype was the insufficient convergence type. The age distribution of patients varied in different months, with a concentration of surgeries for strabismus patients in the 7-12 years old age group during the months of July and August each year.

Outcomes for maximal bilateral lateral rectus recession in large-angle exotropia.

BACKGROUND: Surgical treatment for large-angle exotropia can be challenging. The aim of this study was to evaluate short-term surgical outcomes of patients with large-angle exotropia (≥50Δ) undergoing maximal bilateral lateral rectus muscle recession of 10 mm. METHODS: This was a retrospective study of consecutive patients at our institution who underwent maximal bilateral lateral rectus muscle recession for exodeviation ≥50Δ from January 1, 2008, to July 22, 2022. We subdivided the cohort into large-angle exotropia (largest amount of exodeviation at near and/or distance ≥50Δ and <65Δ) and very large-angle exotropia (largest exodeviation ≥65Δ). Patients with a history of prior eye muscle surgery, neurologic deficits, and three- or four-muscle surgery were excluded. RESULTS: A total of 22 patients were included. Mean preoperative exodeviation at distance was 51.9Δ in the large-angle group and 67.5Δ in the very-large-angle group (P = 0.001). Outcomes for the large-angle and very-large angle groups were, respectively, as follows: mean follow-up, 31.1 weeks and 11.8 weeks (P = 0.97); success, 75.0% and 16.7% (P = 0.02); undercorrection rates, 18.7% and 83.3% (P = 0.01); and mean postoperative exodeviation at distance, 3.7Δ ± 6.3Δ and 28.0Δ ± 13.5Δ (P = 0.001). CONCLUSIONS: Our study identified good surgical outcomes (75%) with maximal bilateral lateral rectus muscle recession of 10 mm in treating patients with large-angle exotropia between 50Δ and <65Δ. Other surgical techniques such as recession-resection and three- or four-muscle surgery may result in better outcomes when treating patients with exotropia ≥65Δ.

[Application of modified fusion convergence index in intermittent exotropia].

Objective: To investigate a modified fusional convergence parameter-total convergence amplitude/distance angle and its relationship with exotropia control, stereoacuity, and other visual functions in intermittent exotropia. Methods: The cross-sectional study included children diagnosed with intermittent exotropia at the First Affiliated Hospital of Nanjing Medical University from August 2020 to June 2021. A modification was made by combining total convergence amplitude using synoptophore and distance angle at distance using prism bars to calculate total convergence amplitude/distance angle. Exotropia control at distance and near measured by Office-based Scale for Assessing Control was classified as good control (scale 0-1) and poor control (scale 2-5). Statistical analysis was performed using Spearman correlation analysis, Mann-Whitney U test, Fisher's exact test, χ2 test, logistic regression analysis, and mediation effect analysis. Results: The study included 212 patients, of which 105 (49.5%) were male and 107 (50.5%) were female. The median (interquartile range) age was 9.0 (8.0, 10.0) years. Of 211 cases, 201 (94.8%) had binocular fusional function, while 11 cases (5.2%) did not have binocular fusional function. Among patients with binocular fusional function, inverse correlation was observed between total convergence amplitude and exotropia control scores for both distance (r=-0.427, P<0.001) and near (r=-0.194, P=0.006). Total convergence amplitude/distance angle was an independent predictive factor for exotropia control at distance (OR=0.195; 95%CI, 0.060-0.630; P=0.006) and near (OR=0.252; 95%CI, 0.085-0.746; P=0.013). Stereoacuity at distance (OR=3.110; 95%CI, 1.311-7.379; P=0.010) and near (OR=2.780; 95%CI, 1.401-5.517; P=0.003) were also factors associated with distance exotropia control. Mediation analysis revealed that stereoacuity was not a mediating factor between the ratio and distance control (distance: P=0.066; near: P=0.181). In patients with ratio≥1.5 °/PD, all the 15 patients demonstrated good control. On the contrary, patients with ratio<1.5 °/PD showed worse exotropia control (distance: P=0.001; near: P=0.040) and larger angles of deviation (distance: P<0.001; near: P<0.001). Conclusion: The modified fusional ratio, total convergence amplitude/distance angle, combining synoptophore and prism bars, could be used to evaluate the severity of intermittent exotropia. A higher ratio may be associated with poorer exotropia control. Though it may also be associated with distance exotropia control, stereoacuity is not the mediating factor between the modified ratio and distance exotropia control.

Binocular Summation With Quantitative Contrast Sensitivity Function: A Novel Parameter to Evaluate Binocular Function in Intermittent Exotropia.

Purpose: Intermittent exotropia (IXT) is the most common form of strabismus. Surgery can potentially improve binocular function in patients with IXT. We aimed to evaluate binocular function using a novel parameter-binocular summation ratio (BSR), measured using quantitative contrast sensitivity function (CSF) in patients with IXT before and after surgery. Methods: Prospective study of 63 patients with IXT and 41 healthy controls were consecutively enrolled and underwent quantitative CSF testing binocularly and monocularly. BSR was calculated by dividing the CSF of the binocular value by the better monocular value. Forty-eight patients with IXT underwent strabismus surgery. BSR, stereoacuity, fusion ability, and strabismus questionnaires were assessed pre-operatively and 2 months postoperatively. Results: Sixty-three patients with IXT (median age = 9 years) compared with 41 healthy controls showed a worse mean BSR based on all CSF metrics at baseline (the area under the log CSF [AULCSF], spatial frequency [SF] cutoff, and contrast sensitivity at 1.0-18.0 cpd SF). All 48 patients with IXT showed successful alignment after surgery, and there were significant improvements in BSR based on the AULCSF, SF cutoff, and contrast sensitivity at 6.0, 12.0, and 18.0 cpd SF, respectively. The distance stereoacuity and fusion ability also improved after surgery, and a better BSR was associated with better stereoacuity and fusion. For strabismus questionnaires, the psychosocial subscale scores improved postoperatively, whereas the functional subscale scores did not change. Conclusions: BSR based on quantitative CSF can characterize binocular function across a range of spatial frequencies and can be used as a supplemental measurement for monitoring binocularity in patients with IXT in clinical settings.

Visual and auditory attention defects in children with intermittent exotropia.

BACKGROUND: Previous studies have shown that children with intermittent exotropia (IXT) have a higher rate of psychiatric abnormalities as they grow up, such as attention deficit. This study explored visual and hearing attention among children with IXT, and evaluated its association with clinical characteristics and cognitive development. METHODS: Forty-nine children with a diagnosis of IXT and 29 children with traditional development were recruited. The Integrated Visual and Auditory Continuous Performance Test (IVA-CPT) was used to measure the subjects' full-scale response control quotient (FSRCQ), full-scale attention quotient (FSAQ), auditory response control quotient (ARCQ), auditory attention quotient (AAQ), visual response control quotient (VRCQ), and visual attention quotient (VAQ). The Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) was used to assess their cognitive function. The differences between the scores of children with IXT and normal controls were analyzed. RESULTS: The results showed that the FSRCQ, FSAQ, ARCQ, AAQ, VRCQ, and VAQ of children with IXT were all lower than those of normal controls with the same age (P < 0.05). The level of attention was significantly correlated with the age of strabismus onset (P < 0.05), but not with the degree of strabismus, stereopsis, or fusion control score. In addition, audiovisual attention was correlated significantly with their cognitive development level. The random forest classifier prediction model showed that age of strabismus onset was an important predictor of attention. CONCLUSION: Children with IXT have lower visual and auditory attention and control than their peers, and the age of onset of strabismus may be a major factor.

Occurrence of Dry Eye Disease in Patients With Concomitant Strabismus: A Preliminary Cross-sectional Analysis.

PURPOSE: To determine the effects of strabismus on dry eye parameters. METHODS: In this cross-sectional study, the preliminary assessment of ocular parameters related to dry eye disease was performed in patients with untreated concomitant strabismus. In total, 204 patients with concomitant strabismus and 125 volunteers without strabismus (4 to 30 years old, 170 male and 159 female) were enrolled. The Ocular Surface Disease Index questionnaire (OSDI) was administered, and ocular surface was examined using the Oculus Keratograph 5M (Oculus Optikgeräte GmbH) to collect data on tear film break-up time (TBUT), ocular redness index (based on bulbar conjunctival blood vessel engorgement), and meibomian gland atrophy. Subgroup analysis was performed based on strabismus type (concomitant exotropia, concomitant esotropia, and non-strabismus); age (juvenile versus adults age > 18 years); and 5- to 10-year and 10- to 20-year strabismus course, according to an age of 12 years. RESULTS: Concomitant exotropia and esotropia were reported in 134 and 70 patients, respectively. A total of 125 healthy volunteers were recruited. The three groups showed significant differences in the ocular redness index (right eye: P = .012, left eye: P = .018). In contrast, other parameters were not significantly different. Similarly, no statistical differences in ocular surface indicators were observed when patients were divided by age (P > .05 for all) and the 5- to 10-year and 10- to 20-year strabismus course. The meibomian gland showed varying degrees of atrophy in both the strabismus and non-strabismus groups. CONCLUSIONS: Strabismus does not affect tear film stability with age in this cohort with constant strabismus up to 30 years, indicating that strabismus may not increase the risk of dry eye disease. [J Pediatr Ophthalmol Strabismus. 2024;61(1):30-37.].

Surgical Approach and Reoperation Risk in Intermittent Exotropia in the IRIS Registry.

Importance: There is no consensus on the optimal surgical treatment for children with intermittent exotropia (IXT). Objective: To compare the 5-year reoperation rates for children with IXT treated with horizontal muscle strabismus surgery using bilateral lateral rectus recession (BLR) vs unilateral lateral rectus recession with medial rectus resection (RR). Design, Setting, and Participants: This cohort study examined data obtained from the Intelligent Research in Sight (IRIS) Registry on 7482 children (age, <18 years) with IXT who underwent horizontal eye muscle strabismus surgery between January 1, 2013, and December 31, 2017. Children undergoing initial surgeries involving 3 or more horizontal muscles, vertical muscles, or reoperations were excluded. Main Outcomes and Measures: The primary outcome was the adjusted cumulative incidence of repeat horizontal muscle surgery within 5 years after the initial surgery. Reoperation risk was analyzed using adjusted hazard ratios (AHRs) derived from multivariable Cox regression models, adjusting for individual demographic and surgical factors (age, sex, race and ethnicity, US Census region, and surgeon subspecialty). Data were analyzed between January 16 and September 20, 2023. Results: The study included 7482 children (median [IQR] age at initial surgery, 6 [4-9] years; 3945 females [53%]) with IXT treated with horizontal muscle strabismus surgery. Bilateral lateral rectus recession was performed more frequently than RR (85.3% vs 14.7%, P < .001), especially in younger children (rates of BLR vs RR by age: age 0 to ≤4 years, 88.4% vs 11.6%; age 5 to ≤11 years, 84.7% vs 15.3%; age 12 to ≤17 years, 78.1% vs 21.9%; P < 0.001). After data adjustment, the 5-year cumulative incidence of reoperation was 21.3% (95% CI, 20.1%-22.5%). The adjusted 5-year cumulative incidence of reoperation was higher for BLR than for RR (22.2% vs 17.2%; difference, 4.9%; 95% CI, 1.9%-8.0%). Unilateral lateral rectus recession with medial rectus resection was associated with a lower 5-year reoperation risk compared with BLR (AHR, 0.77; 95% CI, 0.64-0.93). Younger age at time of initial surgery was associated with a higher reoperation risk (AHR per 1-year decrease, 1.09; 95% CI, 1.07-1.11) after adjusting for all other covariates. Conclusions and Relevance: In this nationwide registry, approximately 1 in 5 children with IXT underwent reoperation within 5 years after the initial surgery. Children treated with RR were less likely to require a reoperation within 5 years compared with those treated with BLR. Further efforts to identify modifiable risk factors for reoperation are needed to reduce the surgical burden and improve outcomes for children with IXT.

Efficacy of Soft Contact Lenses for Myopia Control: A Systematic Review.

PURPOSE: To summarize and analyze critically the scientific evidence focused on the effectiveness of the use of hydrophilic contact lenses (HCLs) in myopia control, as well as their impact on visual quality and the involvement on the accommodative and binocular function. METHODS: This systematic review was developed selecting all original studies which evaluated HCLs for myopia control with follow-up of at least 1 year. Eligible randomized controlled trials (RCTs) were retrieved from PubMed MEDLINE and Scopus. Methodological quality of the studies was assessed using the Critical Appraisal Skills Programme (CASP) for RCTs. RESULTS: The search provided a total of 276 articles, selecting 13 according to the inclusion and exclusion criteria. The majority of studies evaluating the effectiveness of HCL showed a good efficacy in myopia progression, providing a good quality of vision. The quality of these studies was found to be suitable according to the CASP tool. The accommodative and binocular function with these lenses was evaluated in few studies, reporting a trend to an increase in the accommodative response and exophoria in near vision, while maintaining good level of stereopsis. Aberrometry and pupillometry were only studied in one trial, in which the authors did not find changes in these variables after the use of a myopia control HCL. CONCLUSIONS: There is a strong evidence about the effectiveness of different HCLs designs for slowing down myopia progression in children, providing all of them good levels of visual quality. However, there is still poor evidence about changes in accommodation and binocular function, as well as in pupil size and aberrometry with myopia control HCLs, being necessary more studies focused on this issue.