Article

Long-term outcome of uncomplicated infantile exotropia

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Abstract

The term congenital exotropia (XT) is typically reserved for patients presenting in the first year with a large, constant angle, however, no published study provides a rationale for this restrictive definition. In this study, the present classification system for XT was evaluated and differences between infants with constant versus intermittent XT at presentation were characterized. Medical records of all patients diagnosed with XT before 12 months of age between 1980 and 1994 were identified by computer search. Exclusion criteria included previous eye muscle surgery, resolution of the XT by 3 months of age, and concomitant systemic or ocular disease. Patients were separated into intermittent XT and constant XT groups. The clinical characteristics and outcomes of these two groups were compared. Of 2018 patients examined on our service during the first year of life for all causes, 23 (1.1 %) met the inclusion criteria. Follow-up data of more than 1 year was available for 13 patients, and of these, 46% had constant XT. The 2 groups had similar clinical features at presentation except for a larger initial angle in the constant XT group (P =.02). Average follow-up was 58 months (range: 13-158 months). Twelve patients (92%) required surgery. The reoperation rate was 27%, and 82% had final horizontal deviations of less than 10 PD. The incidence of A/V-patterns (38%), dissociated vertical deviation (46%), and binocularity (70%) was similar between groups. Half of infantile XT patients may present with intermittent XT, with similar clinical outcomes regardless of presentation. Surgical intervention resulted in successful alignment in most cases. More than half the patients developed measurable stereopsis, but none achieved bifixation.

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... Infantile exotropia or primary infantile exotropia is the term used to describe patients who are otherwise healthy and present with exotropia in the first year of life. 35 Under the umbrella of infantile exotropia, there is congenital exotropia that is usually defined as an idiopathic, large angle (mean angle = 42 ∆) constant exotropia, and early onset IXT (or known as infantile IXT) that usually has a smaller angle (mean angle = 31 ∆). 36 At presentation, 54% of infantile exotropia is intermittent in nature. ...
... 36 At presentation, 54% of infantile exotropia is intermittent in nature. 35 Transient ocular misalignment during the first few months of life is known to be present during normal development 37 and only misalignment that persists after 3 months of age should be regarded meaningfully as having exotropia. 35 The presentation and treatment of convergence insufficiency is significantly different from divergence excess and basic exotropia, 38 so for this review the focus will be on divergence excess and basic exotropia types of IXT only. ...
... 35 Transient ocular misalignment during the first few months of life is known to be present during normal development 37 and only misalignment that persists after 3 months of age should be regarded meaningfully as having exotropia. 35 The presentation and treatment of convergence insufficiency is significantly different from divergence excess and basic exotropia, 38 so for this review the focus will be on divergence excess and basic exotropia types of IXT only. ...
Article
Introduction: Intermittent exotropia (IXT) is a common form of strabismus. It is an outward deviation of one eye typically when viewing at distance. Symptoms include, but are not limited to double vision, eyes feeling tired, excessive blinking, and reduced quality of life. Its clinical characteristics are distinctive from other types of strabismus. This paper provides a comprehensive review of prevalence, classification, risk factors, natural history and clinical characteristics of the divergence excess and basic exotropia types of IXT. Methods: Search strategies involving combination of keywords including intermittent exotropia, exotropia, divergences excess, basic exotropia, prevalence, incidence, classification, terminology, risk factor, natural history, observation, angle of deviation, control, control score, symptom, quality of life, suppression, anomalous retinal correspondence, AC/A, accommodative convergence/accommodation, accommodative convergence, convergence, accommodation, vergence, incomitance and vertical were used in Medline. All English articles from 1900/01/01 to 2020/09/01 were reviewed. The reference list of the identified article was also checked for additional relevant article. Studies focused on animal model or strabismus associated with neurologic disorder or injury were excluded. Results: The estimated prevalence of IXT in children ranges from 0.1% to 3.7%. Hypoxia at birth and being female are potential risk factors of IXT. Using validated measures of control, multicenter prospective studies showed that the rate of conversion from IXT to constant exotropia is low. The angle of deviation is the most reported outcome measure in studies of IXT. It is often used to represent the severity of the condition and has been suggested as one of the four core outcomes for studies of the surgical management of IXT. Control of exodeviation is one of the four suggested core outcomes for study of surgery of IXT and is considered the main parameter of disease severity. Several validated tools for quality of life score are available to evaluate the subjective severity of IXT. Discussion: We reviewed the prevalence, classification, risk factors, natural history and clinical characteristics of the divergence excess and basic exotropia types of IXT. Further research into these areas, especially its clinical characteristics (e.g. suppression, dual retinal correspondence), will increase our understanding of this condition and potentially lead to better management of this common form of strabismus.
... 1 Surgical intervention for infantile exotropia before the age of 24 months is recommended to obtain optimal motor and sensory results. [2][3][4][5][6][7][8] However, in most infantile exotropia cases, the outcomes of long-term ocular alignment after surgery have been disappointing, with the major reason for unsuccessful postoperative results yet to be determined. 1 Recently, the most common procedure for infantile exotropia has been the use of bilateral lateral rectus recession (BLRR), [2][3][4][5][6][7][8][11][12][13][14][15] unilateral lateral rectus recession (ULRR), or unilateral lateral rectus recession and medial rectus resection (uniRandR). ...
... [2][3][4][5][6][7][8] However, in most infantile exotropia cases, the outcomes of long-term ocular alignment after surgery have been disappointing, with the major reason for unsuccessful postoperative results yet to be determined. 1 Recently, the most common procedure for infantile exotropia has been the use of bilateral lateral rectus recession (BLRR), [2][3][4][5][6][7][8][11][12][13][14][15] unilateral lateral rectus recession (ULRR), or unilateral lateral rectus recession and medial rectus resection (uniRandR). [13][14][15][16] However, the surgical results of these procedures for infantile exotropia are yet to be definitively proven. ...
... Most long-term outcomes for infantile exotropia after ocular alignment surgery are disappointing. [2][3][4][5][6][7][8] Biglan et al reported that reoperations were required in 4 (40%) of 10 patients who underwent initial surgery for infantile exotropia. 3 Hunter et al also reported a 67% success rate for the initial surgery in 12 cases of infantile exotropia. ...
Article
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Purpose: To evaluate the effects of bilateral medial rectus resection (BMRres) on motor outcomes in infantile exotropia. Methods: We evaluated 19 cases of infantile exotropia surgery. The mean age at surgical alignment was 4.8±3.4 years (range, 1.5-11.8 years). The surgical procedures included BMRres (5 cases), BMRres with unilateral lateral rectus recession (ULRR) (3 cases), bilateral lateral rectus recession (BLRR) (8 cases), unilateral lateral rectus recession and medial rectus resection (uniRandR) with contralateral lateral rectus recession (2 cases), and uniRandR (1 case). After dividing the cases into two groups (BMRres group, n=8; other group, n=11), the outcomes at 1 day and at 1, 3, and 6 months after surgery were compared. Surgical outcomes were defined as (1) success: distant esotropia ≤5 prism diopters (Δ) or exotropia ≤10Δ, (2) recurrence: exotropia >10Δ, or (3) overcorrection: esotropia >5Δ. Results: Although postoperative distant deviations at 1 day were not different between the two groups, the BMRres group showed smaller distant deviations at 1, 3, and 6 months than the other group (p=0.015, 0.019, and 0.006, respectively). Success rates of the BMRres and other groups were 88% and 73% at 1 day, 100% and 36% at 1 month, 88% and 27% at 3 months, 88% and 18% at 6 months, respectively. Although there were no significant differences between the two groups within 3 months after surgery, surgical outcomes in the BMRres group 6 months after surgery were significantly better than those in the other group (p=0.003). Conclusion: BMRres is a better procedure than others for infantile exotropia to achieve desirable motor outcomes after surgery.
... In a study by Hiles and Biglan [8], 93% of infantile exotropic patients with a history of operation before 2 years of age showed fusion on the Worth four-dot test, and 75% responded to the Titmus stereo test in near distance; meanwhile in some other studies, sensory outcomes were disappointing [3,9]. Elsewhere, Choi and Kim [10] found that only 25% of their infantile exotropic patients who underwent surgery before the age of 1 year achieved good sensory outcomes after 12 months of follow-up. ...
... Infantile exotropia is defined as a large and constant outward eye deviation with an onset age of up to 12 months [1,2]. As reported by different studies, even with early surgery, bifoveal fixation is less likely to be obtained in these cases [3,9]. ...
... Hunter et al. [3] reported the 1-year follow-up sensory results of 13 infantile exotropic patients with the same distribution of 50% between the intermittent and constant exotropic patients. Postoperative binocular vision was achieved in 70% of cases, while none of the included patients achieved bifixation. ...
... Infantile exotropia is defined by idiopathic, large-angle, constant exotropia appearing in the first six to 12 months of life [1,2] . Based on the literature, infantile exotropia has an incidence rate of 1.1% [3] and it is reported to affect about one per 30,000 infants in the general population [4] . Early surgery is essential to achieve optimal motor and sensory outcomes [2,5] . ...
... In a study by Hiles et al. [8] , 93% of infantile exotropic patients with a history of operation before two years of age showed fusion on the Worth four-dot test, and 75% responded to the Titmus stereo test in near distance; meanwhile in some other studies, sensory outcomes were disappointing [3,9] . Elsewhere, Chio et al. [10] found that only 25% of their infantile exotropic patients who underwent surgery before the age of one year achieved good sensory outcomes after 12 months of follow-up. ...
... Infantile exotropia is defined as a large and constant outward eye deviation with an onset age of up to 12 months [1,2] . As reported by different studies, even with early surgery, bifoveal fixation is less likely to be obtained in these cases [3,9] . ...
Article
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Purpose: We aimed to determine the long-term motor and sensory outcomes of patients with infantile exotropia. Methods: In this longitudinal retrospective (historical cohort) study, the records of 76 patients with infantile exotropia were Studied. Subjects with constant exotropia manifesting before the age of 1 year who were at least 5 years old at recruitment time between 2008 and 2017 were included. Results: The medical records of 26 patients were excluded due to not participating in follow-up examinations or having incomplete records. In total, 54 infantile exotropic patients (51.9% male) with a mean age of 11.1 ± 6.8 years and follow-up of 4.99 ± 3.58 years were studied. Postoperative sensory outcomes (central stereopsis [<60 sec/arc], peripheral fusion [60-3,000 sec/arc], and non-stereopsis [>3,000 sec/arc]) were observed in 38.9%, 38.9%, and 21.2% of patients, respectively. In terms of postoperative motor outcomes, 69%, 24%, and 7% were achieved as orthophoria, residual exotropia, and consecutive esotropia, respectively. Patients with a higher surgical age (p = 0.022) and better visual acuity (p = 0.004) had significantly better sensory outcomes, while higher preoperative deviation resulted in more suppression (p = 0.039, rs = 0.218). Conclusions: With rates of 69% for motor success and 78.8% for sensory success, surgical outcomes of infantile exotropic patients seems to be favorable. Further studies are recommended to verify our findings.
... It has also been reported that there are two types of infantile exotropia before 1 year of age; early onset intermittent exotropia and primary infantile exotropia which do not have difference in their motor outcome [3]. Surgical management is necessary in most cases of infantile exotropia Based on previous reports, the eyes aligned successfully before 24 months of age have optimal motor and sensory outcomes [4][5][6]. Surgery at an older age might have an increased risk of recurrence and poor sensory outcomes. On the other hand ,proponents of surgery at an older age (beyond 2 years) note that early surgery might cause overcorrection and monofixation syndrome promoting amblyopia [7][8][9]. ...
... However, several studies show good sensory outcomes when operated before 2 years of age due to improvement in motor alignment and chances of improvement of binocular fusion [5,6]. Other factor which played a role was the constancy where surgical correction of early onset intermittent exotropia could be delayed since they had stronger sensorial adaptation [4]. Suh and Park., et al. have showed that age does not affect the surgical outcomes [14,16]. ...
Article
Full-text available
The purpose of our study is to determine the motor and sensory outcomes in children undergoing surgery for infantile exotropia after age of 2 years and to review the association of pre-operative variables with surgical outcomes. In this retrospective study, we included patients who were diagnosed as infantile exotropia with a deviation of > 25 Prism diopters (PD) before 12 months age and subsequently underwent strabismus surgery at a single centre from 2014 to 2019. Postoperative motor alignment was assessed at 6 weeks and binocular sensory status was assessed using Worth 4-Dot (WFDT) and Titmus stereoacuity tests at 6 months follow up. A total of 30 patients were analysed. At 6 weeks post-op, motor success was seen in 24 patients (80%), whereas 6 patients (20%) constituted failure group which included 5 patients (17%) with a recurrence and 1 (3%) with an overcorrection. At 6 months post-op, measurable stereopsis was present in 15 patients (50%) with a stereopsis better than 400 sec of arc in 12 patients (40%), binocular single vision was present in 6 patients (20%) on WFDT. Smaller pre-operative angle of deviation was significantly associated with motor success for distance (p = 0.009) and near (p = 0.020). Smaller pre-operative angle for distance was associated with better sensory outcomes (p = 0.041). Pre-operative vision, age at surgery and duration of misalignment did not show statistically significant association with motor and sensory outcomes. Thus we conclude, smaller pre-operative angle of deviation for distance and near are associated with good motor and sensory outcomes. Older age at surgery in this study had outcomes comparable to younger age group reported in previous studies. The association of surgical outcomes with pre-operative vision and duration of misalignment could not be proven by this study.
... In such young patients, it can be difficult to distinguish between these two entities. Hunter et al. (2001) found that, except for the larger angle observed in congenital XT, distinction between the latter and intermittent exotropia can be difficult in infants presenting within the first 12-months of life, where rates of strabismus associated abnormalities including A-or V-patterns, oblique muscle overaction, nystagmus or dissociated vertical deviation (DVD) are similar between both groups. They raised the question of whether they are simply variable expressions of the same disease where most infantile XTs' would have an intermittent phase initially while those that are intermittent at presentation can become constant if control is poor. ...
... However, Saunders & Trivedi (2008) suggest that at least gross binocularity is achievable in both subgroups, with X(T) more able to achieve measurable stereopsis or even bifoveal fixation than XT. Hunter et al. (2001) retrospectively analysed 13 patients with XT presenting before the age of one year and split their cohort into constant XT and X(T) groups where 92% underwent surgery for constant exotropia or progressive loss of control of X(T). Post-operatively, 27% needed further surgery within the follow up range of 13-158 months. ...
Article
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Aim: To describe an unexpected sensory outcome in an adult male who is seeking ocular re-alignment for a psychosocially symptomatic large non-specific exotropia with suppression. The primary diagnosis was infant onset exodeviation of unclear diagnosis, was managed with bilateral strabismus surgery at two years of age, little memory of follow-up. Result: Measurable binocular single vision (BSV) was demonstrable following surgery at 17 years of age, albeit slowly between two weeks and six months postoperatively and subsequently enhanced. His newly acquired sub-optimal BSV led to symptomatic occupation-associated asthenopia. Following two subsequent operations over a 15-year period, he has stable, symptom-free ocular realignment within three prism diopters of orthophoria and performing tasks that require extended periods of near-vision activity. Conclusion: Delayed high levels of stereovision were unexpectedly achieved in an adult with infant onset exotropia with pre-operative sensory suppression that was surgically aligned to near orthophoria. The re-establishment of BSV in such a clinical scenario has to attain a level that is robust enough to meet an individual's social and occupational needs.
... [13][14][15][16] Views on surgical management are equivocal. [17][18][19] It is reported that even after surgery to treat IXT, there is a strong tendency for reoperation (up to 60%) [19][20][21][22][23] or recurrence (up to 65%) [23][24][25][26] of IXT. Although surgical approaches are commonly adopted, systematic reviews 14,15 have reported a lack of randomised clinical trials comparing the effectiveness of surgery to observation alone. ...
Article
Purpose To evaluate the short‐term (1 week after completion of treatment) effect of office‐based vergence and anti‐suppression therapy (OBVAT) on the Office Control Score when compared to observation alone in children with small‐to‐moderate angle intermittent exotropia (IXT). Methods In this single‐masked (examiner masked), two‐arm, single‐centre randomised clinical trial, 40 participants, 6 to <18 years of age with untreated IXT, were randomly assigned to OBVAT or observation alone. Participants assigned to therapy received 60 min of OBVAT with home reinforcement once per week for 16 weeks. Therapy included vergence, accommodation and anti‐suppression techniques. The primary outcome measure was the comparison of the distance Office Control Score between the two groups at the primary outcome visit (i.e., 17‐week follow‐up visit). Results At the primary outcome visit, the OBVAT group ( n = 20) had a significantly better distance Office Control Score (adjusted mean difference: −0.9; 95% CI: −0.2 to −1.5; p = 0.008; partial eta squared: 0.19) than the observation group ( n = 16). Participants from the OBVAT group were more likely than those from the observation group to have ≥1 point of improvement at the 17‐week visit (OBVAT group: 75%; Observation group: 25%; p = 0.006). Conclusions In this randomised clinical trial of participants aged 6 to <18 years with IXT, we found that the OBVAT group had a significantly better distance Office Control Score than the observation group at the 17‐week visit. This study provides the first data from a randomised clinical trial demonstrating the effectiveness of OBVAT for improving the control of IXT. Eye care practitioners should consider OBVAT as a viable, non‐surgical treatment option for IXT. A full‐scale randomised clinical trial investigating the long‐term effectiveness of OBVAT in treating IXT is warranted.
... Choi and Kim described two types of infantile exotropia; early-onset intermittent exotropia and primary infantile exotropia (2). More than 90% of patients with infantile exotropia eventually need surgery, resulting in successful alignment and limited binocularity in most patients (4). Although many studies have studied factors associated with infantile exotropia's surgical results, there is a shortage of knowledge about preoperative deviation effects on postoperative outcomes (5)(6)(7)(8). ...
Article
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Background: This study aims to assess the impact of preoperative deviation on surgical success and sensory function in infantile exotropia. Furthermore, to assess the effects of late surgical timing in these patients.Materials and Methods: This retrospective study evaluated 16 subjects with infantile exotropia that underwent surgical management between 2012 and 2018. Patients with deviation ≤ 50 prism diopters (PD) were added to Group 1, and Patients with deviation > 50 PD were added to Group 2 to assess the impact of preoperative deviation on surgical success and sensory function. The surgical success is descri-bed as ≤5 PD esotropia and ≤10 PD exotropia for patients. The Titmus stereopsis and Worth 4-Dot tests were used for sensory function assessment.Results: The average preoperative deviation was 50,63 ± 18,7 PD (20-90). The median age at the time of surgery was 73 (24-400) months. Surgical success was observed in 75% of the patients after the first surgery, and surgical success was observed in all patients after the second surgery. The sensory function was assessed in 11 testable patients (68.7%), of which 5 (45.4%) fusion was observed in the Worth 4-Point test, and 2 (18.1%) achieved measurable stereopsis. While the preoperative deviation had an effect on fusion, it had no effect on stereopsis and surgical success(p=0,015; p=0,45; p=0,77 respectively).Conclusions: The smaller preoperative deviation may be associated with a higher rate of sensorial fusion development. Furthermore, relatively high surgical success can be achieved with late surgical timing in these patients.Keywords: Exotropia, Preoperative deviation, Strabismus, Stereopsis
... Infantile exotropia refers to the onset of exodeviation within 1 year after birth. It is broadly classified as intermittent and constant strabismus based on the clinical features [1]. Infantile exotropia is associated with neurological, ocular, or craniofacial anomalies, but may also present in the healthy infants, a condition referred as primary infantile exotropia (PIE) [2][3][4]. ...
Article
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Background The surgical outcome is usually not satisfactory for treatment of primary infantile exotropia (PIE) with large exodeviation angels of more than 50 prism diopters (PD). Here, we evaluate the effectiveness of augmented bilateral lateral rectus muscle recession (ABLRR) in treatment of PIE with large deviation angles. Methods A retrospective analysis was performed for 25 patients with PIE who underwent ABLRR. ABLRR was performed using a hemi-hang-back technique. Ocular alignment, ocular motility and binocular vision were evaluated pre- and postoperatively. Results Fourteen males and 11 females with PIE were included in this study, with a mean age of (3.92 ± 2.02) years (range, 1–7 years). The average exodeviation angle was (−66.32 ± 7.84) PD (range, −60–−80 PD) preoperatively. All patients underwent ABLRR using the hemi-hang-back technique. Three of them underwent bilateral inferior oblique muscle anterior transposition in the same operation. The mean surgical dosage was (11.08 ± 1.19) mm for each lateral rectus muscle. The mean of deviation angel was −2.28 ± 5.08 PD postoperatively (P < 0.05). All patients did not have abduction deficiency after a large amount of lateral rectus recession. Twenty-one of 25 patients (84.0%) achieved orthophoria at the primary gaze position at the final visit, and 13 patients obtained binocular vision. Conclusions ABLRR is an effective and safe surgical procedure for treatment of PIE with a large deviation angle.
... Congenital exotropia refers to the onset of exodeviation within 1 year after birth, and it is broadly classi ed as intermittent and constant strabismus based on the clinical features [1]. Constant exotropia is associated with neurological, ocular, or craniofacial anomalies, but may also present in healthy infants, a condition referred to as primary infantile exotropia (PIE) [2][3][4]. ...
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Background: For the majority of the patients, surgical treatment of primary infantile exotropia (PIE) with large exodeviation angels of more than 50 prism diopters (PD) is not satisfactory. We evaluate the effectiveness of augmented lateral rectus (LR) muscle recession in treatment of congenital exotropia with large deviation angles. Methods: A retrospective analysis was performed for 25 patients with congenital exotropia who had at least 60 prism diopters (PD). Augmented LR recession was performed using a hemi hang-back technique. The ocular alignment, ocular motility and binocular vision were evaluated pre- and postoperatively. Results: There were 14 male and 11 female affected individuals with congenital exotropia included in this study, with a mean age of (3.92±2.02) years (range, 1 - 7 years). The average exodeviation angle was (68.0±8.78) PD (range, 60 - 80 PD) preoperatively. All patients underwent bilateral LR recession, of whom 3 patients underwent bilateral inferior oblique muscle transposition in the same operation. The mean surgical dosage was (11.08±1.19) mm for each lateral rectus muclse. All patients did not have abduction deficiency after a large amount of lateral rectus recession. 21 of 25 patients (84.0%) acquired orthophoria at the primary gaze position at the final visit. 13 patients obtained binocular vision. Conclusions: Augmented bilateral LR recession is an effective and safe surgical procedure for treatment of congenital exotropia with large deviation angles.
... [7][8][9][10] Views on surgical management are equivocal. [11][12][13] It is reported that, even after surgery, there is a strong tendency for reoperation [13][14][15][16] or recurrence 17,18 of intermittent exotropia. Although surgical approaches are commonly adopted, systematic reviews 8,9 have reported a lack of randomized clinical trials comparing the effectiveness of surgery to observation alone. ...
Article
Significance: This study will help to demonstrate the potential value of office-based vergence/accommodative therapy for the treatment of intermittent exotropia and provide data that can be used for planning future clinical trials. Purpose: This study was designed to evaluate changes in the office control score after office-based vergence/accommodative therapy for intermittent exotropia. Methods: This was a prospective, unmasked pilot study. Fourteen Chinese participants aged 6 to 18 years with intermittent exotropia (excluding the convergence insufficiency type) were enrolled. All participants received 60 minutes of office-based vergence/accommodative therapy with home reinforcement once per week for 12 weeks. Therapy included vergence, accommodation, saccades and pursuits, antisuppression, and monocular fixation in binocular field techniques. The primary outcome measure was the change in the office control score from the baseline visit to the 13-week outcome visit. Results: All participants completed the study. The office control score at distance changed by -1.0 (95% confidence interval [CI] = -1.6 to -0.4; P = .005; Cohen's d effect size, 0.93). The distant Look And Cover, then Ten seconds Observation Scale for Exotropia score and distant Newcastle control score total score changed by -0.7 (95% CI, -1.2 to -0.2; P = .02; Cohen's d effect size, 0.55) and -1.9 (95% CI, -2.8 to -1.0; P < .001; Cohen's d effect size, 1.37), respectively. Although there was no significant change in the angle of distance exodeviation (-1.8 prism diopter [Δ] less exodeviation; 95% CI, -3.74 to 0.14Δ; P = .11), a significant change was observed in the near angle (-4.4Δ less exodeviation; 95% CI, -7.3 to -1.5Δ; P = .01; Cohen's d effect size, 0.79). There was no significant change in stereopsis or the Chinese Intermittent Exotropia Questionnaire score. Conclusions: In this select group of children with intermittent exotropia, 12 weeks of office-based vergence/accommodative therapy with home reinforcement resulted in a statistically and clinically significant improvement in the distance control of exodeviation and the near exodeviation magnitude. These results suggest that there is a need for a randomized clinical trial designed to determine the effectiveness of vision therapy as a treatment modality for intermittent exotropia.
... Patients with exotropia who had history of prematurity (defined as a gestational age <37 weeks), trauma or neurological problems (such as developmental delay, seizures, or cerebral palsy), ocular diseases that could affect vision or ocular alignment, history of previous ocular muscle surgery, and follow-up duration <3 years after primary exotropia surgery were excluded. All patients were referred to a pediatrician to exclude neurological disorders [1]. ...
Article
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Purpose: To investigate the effect of preoperative part-time occlusion therapy on long-term surgical success in early-onset exotropia. Methods: The medical records of patients who underwent surgery for exotropia with onset before the first year of age and who were followed for ≥3 years were reviewed. Patients were divided into two groups according to the degree of compliance with part-time occlusion therapy: the good compliance group (>50% adherence rate) and the poor compliance group (≤50% adherence rate). Surgical success was defined as orthophoria to exodeviation less than 10 prism diopters both at distance and near. The level of postoperative stereopsis was compared between the two study groups among total enrolled patients and among those with constant exotropia. Results: Of the 51 patients, 26 were assigned to the good compliance group and the remaining 25 patients to the poor compliance group. The surgical success rate was significantly higher in the good compliance group than in the poor compliance group (80.8% vs. 52.0%, p = 0.040). Among 24 constant exotropia patients (12 patients for each group), the success rate was insignificantly higher in the good compliance group than in the poor compliance group (75.0% vs. 58.3%, p = 0.448). The good compliance group had a better level of stereopsis than the poor compliance group (p = 0.045 for all 44 patients, p = 0.020 for 19 patients with constant exotropia). Conclusions: Preoperative part-time occlusion therapy was useful for improving the surgical outcome of early-onset exotropia and postoperative stereopsis.
... Tradicionalmente se ha considerado que la división en subtipos es importante en cuanto a la planificación de la técnica quirúrgica que se vaya a realizar, sin embargo, recientemente se cuestiona la necesidad de esta distinción en el manejo de los pacientes 12 .Algunos autores han propuesto la intervención precoz para mejorar la estereoagudeza 13 ya que más de la mitad de los pacientes podrá desarrollar estereopsis de alto grado [14][15][16][17] . Esta intervención suele ser una recesión bilateral de los rectos laterales, ya que constituye la técnica estándar 18 . ...
Article
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Purpose: To describe the long-term surgical outcomes of bilateral lateral rectus recession in patients with intermittent exotropia. Methods: Retrospective review of 18 patients diagnosed with intermittent exotropia between 1995 and 2005 who underwent surgical treatment in the Ramon y Cajal Hospital. Results: Of the 18 patients with intermittent exotropia, 50% were basic subtype. All of them underwent bilateral lateral rectus recession, associated with a previous failed botulinum toxin injection in 8 of them. Satisfactory results (less than 10 PD orthophoria) were obtained in 68.2% of the patients after a 4.5-year follow-up period. Conclusions: Bilateral lateral rectus recession is an effective and stable surgical procedure in the long-term motor control of intermittent exotropia, especially in basic subtype. Previous injection of botulinum toxin did not affect the results.
Article
Purpose To report long-term motor and sensory outcomes after unilateral lateral rectus recession–medial rectus resection for infantile constant exotropia. Methods The medical records of patients who had undergone unilateral lateral rectus recession–medial rectus resection for infantile constant exotropia who were followed up postoperatively for a minimum of 4 years were reviewed retrospectively. Results A total of 20 patients were included. The mean age at surgery was 3.21 ± 1.54 years (range: 1.25 to 6.00 years). The mean duration of exodeviation was 2.99 ± 1.61 years (range: 9 months to 6 years). The mean angle of exodeviation was 70.1 ± 20.9 prism diopters (PD) (range: 35 to 90 PD). The median postoperative follow-up was 9.1 years (range: 4 to 24 years). Overall, 12 patients (60%) had surgical success at their last follow-up visit. Age at first surgery, cycloplegic refraction, strabismus duration, preoperative angle of deviation, presence of amblyopia, and the number of exotropia surgeries did not predict motor outcome after surgery. At the last follow-up visit, 20% of patients had residual exotropia and 15% had recurrent exotropia. Peripheral binocular single vision was achieved in 25% of patients and stereopsis in none. Age at first surgery, strabismus duration, and surgical outcome had no effect on sensory outcome. Conclusions In this study, 60% of patients achieved a successful long-term motor outcome and 25% achieved peripheral binocular single vision after unilateral recession-resection for infantile constant exotropia. Stereopsis outcome was nil. Age at surgery and duration of strabismus had no effect on motor and sensory outcomes. [ J Pediatr Ophthalmol Strabismus . 20XX;XX(X):XXX–XXX.]
Article
Introduction: Currently, there is no consensus regarding the management of intermittent exotropia (IXT), which includes both surgical and non-surgical treatment options. Nonsurgical management of IXT has been suggested and includes watchful observation, patching, overminus lenses, prism, and vision therapy/orthoptics. While a significant portion of IXT patients are treated by surgery, it is reported that there is a substantial tendency for reoperation or recurrence of IXT. This paper provides a comprehensive review of non-surgical and surgical treatment options for the IXT. Methods: Search strategies involving combination of keywords including intermittent exotropia, divergence excess, basic exotropia, refractive error, glasses, spectacles, natural history, untreated, observe, occlusion, patch, overminus, overcorrecting minus, prism, vision therapy, orthoptic, anti-suppression, fusion exercise, and surgery were used in Medline. All English articles from 01/01/1900 to 01/09/2020 were reviewed. The reference list of the identified articles was also checked for additional relevant articles. Studies focused on animal models or strabismus associated with neurologic disorders or injury were excluded. The following filters were used for surgical management due to the abundance of reports: full text, randomized controlled trial, review, in the last 5 years. Results: Appropriate optical correction of refractive error is generally the starting point for all management approaches, but there is a lack of randomized clinical trial data regarding this treatment modality. Randomized clinical trial data indicate that both observation and occlusion are reasonable management options for children 3-10 years old, and there were insufficient data to recommend occlusion for children 12-35 months old. While overminus lenses were found to improve the control of IXT when assessed wearing overminus spectacles, this improvement did not persist after the treatment ended. The result of the only randomized clinical trial on the effectiveness of base-in prism indicated that this treatment is no more effective than nonprism spectacles for improving control. A recent randomized clinical trial showed that vision therapy/orthoptics is effective in improving the control of IXT when compared to observation alone. Surgery was found to alter a number of clinical characteristics of IXT, including reducing the distance and near angle of deviation, reducing photophobia, improving health-related quality of life, stereopsis, and the Newcastle Control Score. However, there are no randomized clinical trial data comparing surgery with a control group such as placebo or a no treatment observation group. Discussion: Rigorously designed clinical trials to investigate the effectiveness of non-surgical and surgical treatments for intermittent exotropia are needed.
Chapter
When strabismus is comitant, the angle of deviation is similar regardless of the direction of gaze or the fixating eye. Comitant horizontal deviations are generally not associated with underlying serious CNS pathology; thus, the distinction between comitant and incomitant strabismus is clinically important. In the first few months of life, normal infants may demonstrate variable degrees of esotropia and/or exotropia. The ideal outcome of early surgery for infantile esotropia is attainment of high-grade stereoacuity. More often the large-angle esotropia is converted to a microesotropia (monofixation syndrome) with the development of peripheral fusion and a central suppression scotoma. It is estimated that infantile exotropia is 150–300 times less common than infantile esotropia. In contrast, transient exodeviations are relatively common in healthy neonates. In older children, uncorrected hypermetropia and decompensated monofixation syndrome are the most common etiological factors in acquired comitant esotropia. The clinician must recognize that over time comitant forms of strabismus may develop associated features that may not be comitant and thought to reflect poor binocular vision development. These include latent nystagmus, optokinetic nystagmus asymmetry, dissociated vertical deviation, and inferior oblique overaction. Children with intermittent exotropia and esotropia may have a tendency to squint one eye in bright illumination; hence, the term “squint” has become synonymous with strabismus in some countries. Children with refractive/accommodative esotropia (typically >2.5 diopters of hyperopia) present around age 2–3 years, at a time when toddlers are learning to explore the “near world” at hand.
Article
PurposeThe causative factors of infantile exotropia are unknown. The purpose of this study was to investigate the relationships between the biorbital angle and the pathogenesis of infantile exotropia.Study designRetrospective.Methods Of all patients diagnosed as infantile exotropia with onset prior to 12 months of age between 2010 and 2017, 31 patients without any neurological disorders or developmental delay were identified.The angle between both lateral walls of the orbit, defined as the biorbital angle, was measured in the horizontal plane at the optic nerve and where the horizontal extraocular muscles appeared on axial magnetic resonance imaging (MRI) or computed tomography (CT) of the orbit. These patients’ data were compared with those of 129 ophthalmologically normal children. All subjects of this study were Japanese.ResultsThe mean biorbital angle was significantly larger in patients with infantile exotropia than in the normal children (106.6 ± 5.7° vs 94.2 ± 5.1°, p < 0.001). Of the patients with infantile exotropia, 21 (68%) had an angle outside the 95% confidence interval calculated in normal children. All cases were divided into a constant (15 cases) and intermittent (16 cases) group; there was no significant difference between them in the mean biorbital angles (107.9 ± 5.6° vs 105.4 ± 5.8°, p = 0.224). No correlations were identified between the biorbital angle and the angle of exodeviation, either distant or near.Conclusions Children with infantile exotropia have a larger biorbital angle. This anatomical abnormality may be an associate factor of infantile exotropia.
Book
Full-text available
The subject of strabismus is like a vast ocean; standing by its shores, one cannot assess its full expanse but only by taking a deep plunge into it does one realize its true depth and dimension. The aim of writing this book was to develop a basic understanding, an insight into this complex problem, and to develop a stepwise approach to managing patients. Strabismus (squint) is a sign, Nature’s way of telling us that something is wrong with the eye itself, either structurally, functionally, or with the visual pathways/higher centers controlling the ocular motility. It has a multifactorial etiology. In order to plan the correct management, it is essential to find the causative factors and an attempt should be made to rectify them first before embarking on strabismus surgery. About 80-85% of cases of strabismus are due to mismanaged refractive errors. Explicit conceptual knowledge of refractive errors forms the backbone of strabismus management. There are certain Laws governing ocular movement, which should be kept in mind while assessing a strabismus patient. Listing’s Law describes how a fixed ocular movement takes place around an equatorial plane going through the center of rotation of the eye; hence, the strabismic surgeon should not disturb this plane by too much recession/resection of the recti. According to Hering’s Law, there is an equal and simultaneous innervation of the yoke muscles in both eyes for any direction of gaze (while assessing ocular motility, both yoke muscles should act to the same extent without any under-action/over-action of either member of the group). Sherrington’s Law describes reciprocal innervation of the agonist and the antagonist, so when one muscle contracts, its direct antagonist relaxes. Hence, the strabismologist must understand these basic concepts to interpret complex ocular motility patterns, particularly in paralytic strabismus where secondary muscle changes commonly occur in longstanding cases. Finally, always remember, “Vision before Surgery”; only equal vision in both eyes allows sensory fusion to Lock the ocular alignment in all directions of gaze. However, if the vision is poor in one eye, the absence of sensory fusion will not allow the eyes to Lock even after an excellent squint surgery, and the eye with poor vision will drift outwards under the influence of active divergence in adults. The chapter on "Amblyopia" focuses on the theory as well as the management of amblyopia prior to embarking on strabismus surgery.
Article
Full-text available
Introduction We evaluated the effectiveness of office-based vergence/accommodative therapy with home reinforcement for intermittent exotropia in a private practice environment. Methods This was a retrospective chart review study. Patients who received office-based vision therapy for intermittent exotropia in a private optometric clinic were reviewed. Patients with intermittent exotropia treated with and without strabismus surgery were both included. The pre-therapy baseline data were compared to the re-evaluation data obtained at the last therapy session. All patients received office-based vergence/accommodative therapy administered by a trained therapist during a 60 min office visit every one to two weeks, combined with home reinforcement for a minimum of 15 min, five times per week. The primary outcome measure in this study was the change in the Office Control Score from the pre-therapy visit to the post-therapy visit. The hypothesis was that office-based vergence/accommodative therapy would significantly improve the Office Control Score. Results Forty patients aged from 5 to 22 years old fulfilled the inclusion criteria. Eight of them were postoperative patients. After treatment, there was a change of −1.1 ± 1.6 (p < 0.001, z = 3.73, effect size: 0.42) and −1.1 ± 1.4 (p < 0.001, z = 4.26, effect size: 0.48) in distance and near Office Control Score, respectively. In the subgroup analysis, significant improvements in the Office Control Score were observed in both the operated and unoperated intermittent exotropes at distance and near. Conclusion This study showed that office-based vergence/accommodative therapy with home reinforcement significantly improved the distance and near control of exodeviation in both operated and unoperated intermittent exotropia patients in a private practice environment.
Article
Purpose: To investigate recovery from suppression when the target motor alignment is achieved following surgery for intermittent exotropia. Methods: The medical records of 237 patients who underwent surgery for exotropia were retrospectively reviewed. The age at surgery, sex, preoperative angle of deviation, suppression status, and near stereopsis were investigated. Suppression status was classified as no, alternate, or constant suppression. Target motor alignment was defined as 10 prism diopters (PD) or less of exodeviation or 2 PD of esodeviation at the final visit. Results: The mean age at surgery was 8.2 ± 3.2 years and 115 (48.5%) patients were male. The preoperative angle of deviation was 26.3 ± 5.9 PD and the follow-up postoperative period was 21.6 ± 7.6 months. The preoperative suppression status included 23 (9.7%), 55 (23.2%), and 159 (67.1%) patients who showed no, alternate, or constant suppression, respectively. Two hundred fifteen (90.7%) patients obtained the target motor alignment by the final visit. Of the 144 patients who demonstrated constant suppression preoperatively but achieved the target motor alignment postoperatively, 12 (8.3%) patients demonstrated residual suppression. All 12 of these patients had a preoperative angle of exotropia of greater than 20 PD. Conclusions: Most patients undergoing surgery for intermittent exotropia obtained both successful motor alignment and fusion postoperatively. However, successful motor alignment did not guarantee recovery of suppression when the preoperative angle of exotropia was greater than 20 PD. The preoperative factors and functional implications underlying this finding are unclear and merit further study. [J Pediatr Ophthalmol Strabismus. 2020;57(1):21-26.].
Article
Full-text available
The aim of this retrospective study was to determine the strabismus angle variability and rationality of surgical treatment of strabismus in prematurely born children with neurological impairment during 12-year follow up. Eleven premature infants born in 2003 were included in the study and treated with equal conservative approach from 2005 until 2016. Initial esotropia was found in seven and exotropia in four of eleven children. Changes in the strabismus angle correlated significantly with aging of the children. In children with initial esotropia, the strabismus angle became less convergent (less positive), changed the orientation and became more divergent with aging. In those with initial exotropia, the angle became less divergent (more positive), changed the orientation and became more convergent. Moreover, a significant difference in the strabismus angle was found during the 12-year follow up. Based on our results, due to the variability in strabismus angle, we did not find enough evidence for optimal timing or rationality of strabismus surgery in neurologically impaired children born prematurely.
Article
Purpose: To determine whether age of onset influences surgical outcomes in infantile exotropia. Methods: The medical records of patients at our tertiary care facility who underwent bilateral lateral rectus recession for infantile exotropia during the period 2004-2013 were reviewed retrospectively. Patients were grouped by onset age: 6 months or earlier (E6 group) or later than 6 months (L6 group). Motor outcomes, near stereoacuity, and distance fusional status in both groups were evaluated. Results: A total of 134 patients were included: 35 in the E6 group and 99 in the L6 group. At a mean follow-up of 4.6 years, recurrence occurred in 12 (34%) of the E6 group and 38 (38%) of the L6 group (P = 0.496). Overcorrection occurred in 3 (9%) of the E6 group and in 4 (4%) of the L6 group (P = 0.341). In the analysis of 109 patients eligible for sensory examinations, the E6 group demonstrated a higher proportion of patients with reduced stereoacuity of 80 arcsec or worse (54% vs 25% [P = 0.007]) and suppression (46% vs 12% [P < 0.001]) compared with those in the L6 group. In logistic regression analyses, onset of ≤6 months was significantly associated with reduced stereoacuity (OR = 6.42) and suppression (OR = 37.67) but not with recurrence or overcorrection. Conclusions: In our study cohort, age of onset ≤6 months was associated with worse sensory prognosis for children with infantile exotropia but not with a difference in motor outcomes.
Article
Background and Purpose: Early onset exodeviations in systemically and ocularly healthy young children, diagnosed at less than 1 year of age, may be of the constant, “infantile XT” type, or early X(T) type. The onset of common childhood X(T) is not clearly known. The purpose of this lecture is to discuss theories and characteristics of early onset exodeviations, and report on our observations of infantile XT and early X(T) at Children's Eye Care in Michigan. Patients and Methods: A retrospective review of 470 cases of childhood exodeviations (ages 6 months to 15 years) were reviewed and met inclusion criteria of no prior surgical treatment, no ocular, CNS or craniofacial disease, and no significant prematurity. Thirty-nine cases were diagnosed at less than 1 year of age: thirty-five patients with early X(T) and four patients with infantile XT, based upon a motility evaluation at 6 m and 1/3 m fixation using dissociative methods. The clinical characteristics and outcomes of these two groups were described and compared. Results: Comparing infantile XT and early X(T) groups, reported onset by caregivers was significantly younger in the infantile XT group (3 months vs. 6 months), and size of the deviation at both distance and near fixation ranges was significantly larger in the infantile XT group (XT-43/XT′-48Δ vs. X(T)-25/X(T)′-23Δ). Three of 4 infantile XT patients received surgery, one spontaneously resolved, and all resulted in small, residual XT, and DVD without measurable stereoacuity. Many patients with early X(T) demonstrated good/excellent control at near range and fair/poor control at distance range. Four early X(T) patients who did not receive surgical correction either resolved, remained the same, or decompensated. Surgical correction for X(T) resulted in a 50% success rate for one procedure with a minimum of 2 years postoperative follow-up. Stereoacuity outcomes did not appear to correlate with quality of control. Conclusions: Most healthy children with X(T) are diagnosed by age 5 years, although many have a reported onset by caregivers of less than 1 year of age. Good control of X(T) at near range may preclude early examinations. Motility evaluation by dissociative methods at near and far-range fixation may facilitate early diagnosis. Infantile XT is less common than early X(T), by a ratio of 1:10. Characteristics of infantile XT and early X(T) have significant differences in report onset, deviation size, and outcomes with and without surgical intervention. Patients with either infantile XT or early X(T) may spontaneously resolve over time.
Article
Purpose: To evaluate a group of infants with this disorder to determine the long-term outcome of surgery and to assess the need for neurologic evaluations. Methods: This interventional case series reviewed the records of infants who underwent surgery for the treatment of exotropia with onset during the first year of life. The preoperative ophthalmic and systemic findings, treatment, and developmental and ophthalmic outcomes were reviewed. Surgery was considered successful if the horizontal deviation was less than 10 prism diopters (PD). Developmental assessments were obtained at each visit. Results: Twenty-six patients presented between age 2 and 10 months with exotropia ranging from 20 to 95 PD. Ten (38%) patients had a developmental delay that was recognized at the first visit, 9 of whom had a systemic diagnosis at that time; the other patients remained developmentally normal during a mean follow-up of 7 years. Age at surgery ranged from 4 to 18 months. Surgery was successful in 10 (38%) of 26 patients after 1 surgery and in an additional 13 (50%) of 26 patients after a second surgery. Conclusions: In this study, the need for more than 1 surgery was higher in infantile exotropia when compared to other forms of childhood strabismus, but most children achieved good alignment with one or two surgeries. Developmental delay is common in patients with infantile exotropia, but this was usually recognized at the time of the initial evaluation. In the current patients, routine neurologic screening or imaging of these otherwise developmentally normal infants was not required. [J Pediatr Ophthalmol Strabismus. 200X;XX(X):XX-XX.].
Article
Purpose: To review the association of postoperative ocular alignment, sensory outcomes, and need for reoperation after surgical management of infantile exotropia. Methods: The clinical records of patients who presented with constant infantile exotropia of >25Δand subsequently underwent strabismus surgery at a single center from 2004 to 2014 were reviewed retrospectively. Postoperative binocular sensory status was assessed using Worth 4-Dot and Titmus stereoacuity tests. Patients with postoperative exotropia of >10Δor esotropia of >5Δwere advised to undergo additional surgery. Results: A total of 49 cases were included (28 boys; age at diagnosis, 1-12 months). The patients who underwent reoperation were younger at the time of first surgery (mean age, 13.15 ±1.68 vs 18.58 ± 0.92 months [P = 0.005]). Patients who developed consecutive esotropia were younger at the time of initial operation (P = 0.039). Among 20 patients who were testable for sensory outcome assessment, only 4 patients developed stereopsis, whereas 15 patients achieved bifixation by Worth 4-Dot test. All of the 4 patients with measurable postoperative stereoacuity had initial surgery after 1 year of age. Conclusions: In this patient cohort, earlier surgery did not necessarily lead to better sensory outcomes, and reoperation was associated with younger age at time of first surgery.
Article
Full-text available
Recent studies have implicated exotropia as a risk factor for schizophrenia. We determined whether schizophrenia biomarkers have abnormal levels of expression in extraocular muscles from patients with strabismus and explored whether differences in gene expression between medial and lateral rectus muscles may explain the specific association of schizophrenia with exotropia but not esotropia. Samples from horizontal extraocular muscles were obtained during strabismus surgery and compared with age- and muscle type-matched normal muscles from organ donors. We used PCR arrays to identify differences in gene expression among 417 signaling molecules. We then focused on established schizophrenia-related growth factors, cytokines, and regulators of the extracellular matrix. Among 36 genes with significantly altered gene expression in dysfunctional horizontal rectus muscles, over one third were schizophrenia-related: CTGF, CXCR4, IL1B, IL10RA, MIF, MMP2, NPY1R, NRG1, NTRK2, SERPINA3, TIMP1, TIMP2, and TNF (adjusted p value ≤ 0.016667). By PCR array, expression of three of these genes was significantly different in medial rectus muscles, while eleven were significantly altered in lateral rectus muscles. Comparing baseline levels between muscle types, three schizophrenia-related genes (NPY1R, NTRK2, TIMP2) had lower levels of expression in medial rectus muscles. Despite the surprisingly large number of schizophrenia-related genes with altered gene expression levels in dysfunctional muscles, the lack of specificity for medial rectus muscles undermines a model of shared, region-specific gene expression abnormalities between exotropia and schizophrenia, but rather suggests consideration of the alternative model: that exotropia-induced aberrant early visual experiences may enable and/or contribute as a causative factor to the development of schizophrenia.
Article
Purpose: To determine whether age at surgery influences postoperative outcome in infantile exotropia. Methods: This longitudinal, retrospective study included children who underwent bilateral lateral rectus recession between 2004 and 2012 for an exotropia with onset by 12 months of age. Surgical outcomes were considered failures if recurrence with exodeviation of >8(Δ) or overcorrection with esodeviation of >5(Δ) developed during postoperative period. Univariate and multivariate analyses were conducted to compare the association of age at surgery with development of recurrence and overcorrection. Results: A total of 93 children were included. Mean age at surgery was 3.2 years. At a mean follow-up of 3.6 years, 19 of 93 patients (20.4%) experienced recurrence and 3 (3.2%) had overcorrection. In the multivariate analyses, increased age at surgery was associated with higher risk for recurrence (OR = 1.031 per 1-month; 95% CI, 1.003-1.060). In subgroup analyses, the association was significant only in the constant exotropia group (OR = 1.410; 95% CI, 1.037-1.917) and not in the intermittent exotropia group (OR = 0.995; 95% CI, 0.938-1.056). In both groups, overcorrection was not associated with any factors, including age at surgery. Conclusions: Older age at surgery was associated with risk of recurrence in infantile exotropia with constant deviation, but it was not correlated with surgical outcomes for patients with intermittent exotropia in this study.
Article
Purpose: To review the evolution of theories and practices concerning surgery for exotropia over the last approximately 200 years. Methods: Major ophthalmology texts and relevant references were reviewed to discover experience and thinking concerning the causes of comitant intermittent and constant exotropia and corrective surgical approaches. Results: The concept that excessive divergence is the cause of comitant exotropia has given way to one recognizing that this disorder is a position of rest modified by convergence. Some operations discarded as unreliable or dangerous remain so today. Others continue to be well accepted, whether or not relating to advances in understanding of this condition. Several procedures practiced at former times have regained popularity. Conclusions: Concern for the characteristics of extraocular muscle structure and function has led to surgical thinking that goes beyond consideration only of direction and magnitude of deviation. Sophisticated devices now provide heretofore unavailable information consistent with this new approach. The history of progress in surgery for exotropia is mixed. Although some procedures now employed are new, others currently in favor had been well known and formerly utilized by ophthalmologists for many decades. These should be regarded as rediscoveries or revivals rather than as novel. This review also suggests a need to address how to better report retrospective studies.
Article
Purpose: To determine the incidence and related risk factors of reoperation among patients with infantile exotropia who were operated on at Imam Hossein Medical Center, Tehran, Iran, from 2001 to 2015. Methods: In this study, 82 children (55 girls and 27 boys) with infantile exotropia were divided into two groups 3 months after their first operation: children with horizontal deviation of 10 prism diopters (PD) or less (n = 64; success group) and those with horizontal deviation greater than 10 PD (n = 18; failure group). Patients with deviation of 20 PD or greater were indicated for reoperation. Factors including age at the first operation, preoperative angle of deviation, inferior oblique muscle overaction, dissociated vertical deviation, and A- or V-pattern in relation to reoperation were studied. Sensory status of children older than 5 years was also evaluated using Worth 4-dot and Titmus tests. Results: Reoperation was indicated in 18.30% (n = 15) of patients after 11.50 ± 19 months of follow-up. Pre-operative angle of deviation (P < .001) and surgical approach (P = .017) were statistically different between the failure and success groups. The majority of patients (71%) achieved fusion and gross stereopsis (< 3,000 seconds of arc) after surgery. Conclusions: According to the results, 18.3% of patients with infantile exotropia, especially those with more preoperative exotropia, needed reoperation to achieve good alignment. Although the recession-resection method had better motor results, the authors could not recommend it as a first operation for all patients with infantile exotropia because it was only performed on patients with amblyopia. Gross stereop-sis and binocular fusion were seen in the majority of patients. [J Pediatr Ophthalmol Strabismus. 201X;XX(X):XX-XX.].
Chapter
A number of complex ocular motility disorders are discussed in this chapter. The diversity of these conditions reflects the need for the ophthalmologist to maintain a broad working knowledge of pediatric neurologic disorders along with their ocular motor manifestations. Some clinical features of these conditions (e.g., congenital ocular motor apraxia, congenital fibrosis syndrome) are sufficiently unique that the diagnosis can be established solely on the basis of the clinical appearance. Other disorders either show overlapping manifestations or effectively masquerade as other entities. Unique features of some conditions, such as conjugate ocular torsion in patients with skew deviation, are considered worthy of emphasis because they significantly expand the differential diagnosis. Indeed, assessment of objective torsion (and subjective torsion when possible) is a necessary component of any comprehensive strabismological evaluation [422]. Correction of coexisting torsion can be integrated into the surgical plan, except when the torsion serves a compensatory function, as in patients with skew deviation.
Article
Purpose: To evaluate the long-term surgical outcomes and the clinical features between infantile-onset constant and intermittent exotropia. Methods: The medical records of 67 patients diagnosed as having infantile exotropia before 12 months of age who underwent surgery were reviewed retrospectively. Patients were divided into intermittent exotropia and constant exotropia groups based on presentation before surgery. All patients underwent bilateral lateral rectus recession. Preoperative and postoperative clinical features were investigated. Results: There were 37 children in the intermittent exotropia group and 30 children in the constant exotropia group. The cumulative probabilities of success 3 years after bilateral lateral rectus recession were 91.9% in the intermittent exotropia group and 70% in the constant exotropia group. Constant deviation was more closely associated with both dissociated vertical deviation (DVD) and inferior oblique muscle overaction (IOOA) (P = .009 and P = .009, respectively) and related to poor stereopsis outcome (P = .002) and distance suppression (P = .029). Conclusions: Constant deviation was associated with the development of recurrence, DVD/IOOA, and poor stereopsis after surgery. Constancy of exotropia is a reliable factor for predicting poor surgical outcomes in infantile exotropia at long-term follow-up. [J Pediatr Opthalmol Strabismus. 200X;XX(XX):XX-XX.].
Article
Objective: To evaluate the effect of press-on prism test lor eve position observation and adjustable suture of reeus muscle of early surgical intervention in congenital exotropia. Design: Retrospective case series. Participants: We reviewed 25 subjects diagnosed with congenital exotropia in Beijing Children Hospital in 2008-2012. aged 10 months to 67 months (28.84±16.01 months). Of the 25 cases. 1 case of intermittent exotropia, 24 cases of constant exotropia. 4 cases existed with V sign, 4 cases with DVD, 1 case with V sign and DVD, 1 case with nystagmus. Methods: Pressure prism test (or deviation degree was used in young children before or after surgery. Adjustable suture of recus muscle was used during surgery. The follow-up was performed on 1 day, 2 weeks, 1 months, 6 months, and 12 months after surgery. Main Outcome Measures: The angle of near and far deviation in primary position. Result: Pressure prism test has good compliance in young children. On 1 day after operation. 80% patients had a deviation of less than 10 PD, and 2 weeks after adjusting suture 100% patients had a deviation of <10 PD (P<0.05). On half a year eye position change of strabismus degree was not obvious. One year after the operation (-7.12±3.24Δ) had a tendency to develop in the direction of exotropia with time and surgical success rale was 88%. Conclusion: Press-on prism test can be used in congenital exotropia in young children for preoperative strabismus degree examination. Application of adjustable suture obviously increases the success rate of congenital exotropia.
Article
• Exotropic deviations include exophoria, infantile exotropia, sensory exotropia, consecutive exotropia, intermittent exotropia, and dissociated horizontal deviation. • The decision whether to treat should be based on control, and how to treat is based on the magnitude of the deviation. • Burian’s classic treatment recommendations and classification of exotropia are based on some assumptions that are probably incorrect. They need not be strictly followed. • Intermittent exotropes with a true high AC/A ratio are uncommon but do exist. Standard surgery based on the distance angle frequently results in an overcorrection at near. • Patients with fusional convergence insufficiency are different from exotropes with accommodative convergence insufficiency; the latter have a low or absent AC/A ratio and are difficult to treat surgically; the former do well with orthoptic exercises. • Patients with intermittent exotropia and monofixation syndrome have a poorer sensory outcome after surgery.
Article
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AIM: To observe the changes of binocular vision in V-pattern exotropia children before and after surgical correction, and the effect of training in reconstructing the binocular vision after surgical corrections. METHODS: Sixty V-pattern exotropia children were enrolled in this study and were divided into three groups according to their age: group A (4~6 years old), group B (7~9 years old), and group C (10~12 years old), 20 cases for each group. Patients received routine refraction and ophthalmic examinations. Distance and near deviation were measured by prism-covering method and synoptophore. The simultaneous perception and fusion were examined with a synoptophore, and the stereacuity was measured with stereograms (Titmus). The children who didn't reconstruct binocular vision function 1wk after surgery received binocular vision training. The data were recorded before and 1, 2, 4, and 8wk after surgery. RESULTS: Binocular vision significantly improved among the children after surgery in group A and B(P<0.05). Significantly divergence showed between group C and the other groups 1wk after surgery (P<0.05). Binocular vision of the three groups all significantly improved 8wk after surgery, with no significant differences (P>0.05). CONCLUSION: V-pattern exotropia children can benefit from early surgical correction and training after surgery in reconstruct binocular vision.
Article
Purpose: Although long-term results following repair of esotropia and exotropia in childhood have been reported, the two entities have never been directly compared. Methods: Records of all children younger than 18 years who underwent horizontal strabismus surgery from 2000 through 2012 were reviewed. Children with structural eye pathology, severe vision loss, neurologic disorders, and incomitant or combined horizontal and vertical deviations were excluded. Failure was defined by a second horizontal surgery or a primary position deviation greater than 20 prism diopters (PD) at any time during follow-up (as long as 10 years). A threshold of 20 PD was chosen because families often consider deviations important enough to warrant a first or second surgery if it is larger but not if it is smaller. Results: Of 317 children, 235 with esotropia had surgery at a mean age of 42 months and 82 with exotropia had surgery at a mean age of 60 months. Overall, surgery was successful in 78% of those with esotropia and 65% of those with exotropia. A second surgery was performed in 29 (12%) of those with esotropia and 15 (18%) of those with exotropia. The mean deviation at last follow-up, using absolute values, was 9 PD for esotropia and 10 PD for exotropia. Survival curve success was better for esotropia (P = .008). Conclusion: By survival curve analysis, success was more likely among children with esotropia. Many "failures" slipped beyond the 20 PD threshold only transiently and had deviations that were not noticeable to family or friends. Overall, children did reasonably well long-term following surgery for both esotropia and exotropia. Only 14% of the entire group required a second surgery during an average of 41 months of follow-up. [J Pediatr Ophthalmol Strabismus. 2015;XX(X):XX-XX.].
Chapter
Binocular single vision (BSV) is the ability to use both eyes simultaneously so that each eye contributes to a common single perception. The main purpose of the investigation of the binocular function is to determine whether the aim of treatment should be to restore BSV or to improve the patient's appearance and ensure that he or she has the best possible visual acuity (VA). Suppression, either physiological or pathological, is the cortical inhibition of unwanted visual stimuli, and can affect one or both eyes and can be constant or intermittent. This chapter talks about a number of tests for binocular vision for assessing different aspects. There are many different tests for the assessment of stereopsis and the one chosen is dependent on several factors including age of the patient, level of stereoacuity expected and VA. The chapter also talks about the tests specifically used to assess correspondence.
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Clinical manifestations and surgical outcomes of intermittent exotropia with or without dissociated vertical deviation (DVD) were evaluated.
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In strabismus, potentially either eye can inform the brain about the location of a target so that an accurate saccade can be made. Sixteen human subjects with alternating exotropia were tested dichoptically while viewing stimuli on a tangent screen. Each trial began with a fixation cross visible to only one eye. After the subject fixated the cross, a peripheral target visible to only one eye flashed briefly. The subject's task was to look at it. As a rule, the eye to which the target was presented was the eye that acquired the target. However, when stimuli were presented in the far nasal visual field, subjects occasionally performed a "crossover" saccade by placing the other eye on the target. This strategy avoided the need to make a large adducting saccade. In such cases, information about target location was obtained by one eye and used to program a saccade for the other eye, with a corresponding latency increase. In 10/16 subjects, targets were presented on some trials to both eyes. Binocular sensory maps were also compiled to delineate the portions of the visual scene perceived with each eye. These maps were compared with subjects' pattern of eye choice for target acquisition. There was a correspondence between suppression scotoma maps and the eye used to acquire peripheral targets. In other words, targets were fixated by the eye used to perceive them. These studies reveal how patients with alternating strabismus, despite eye misalignment, manage to localize and capture visual targets in their environment.
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Objet Évaluation de l’âge lors de la chirurgie et de la durée du désalignement qui affecte le résultat chirurgical de l’exotropie infantile chez un enfant en santé âgé de moins d’un an. Méthodes Étude rétrospective des dossiers de 39 patients ayant subi une chirurgie pour diagnostic d’exotropie avec un suivi d’au moins 1 an. Les patients ont été répartis en deux groupes (DP) : « Réussite » (exodéviation ≤8 PD ou ésodéviation ≤5 PD dans l’année suivant la chirurgie sans reprise chirurgicale durant la période de suivi) ou « Échec » (exodéviation ≤8 PD ou ésodéviation ≤5 PD dans l’année suivant la chirurgie, ou reprise chirurgicale pour récurrence ou correction excessive dans la période de suivi). Nous avons évalué l’âge lors de la chirurgie et la durée du désalignement, répartis en cinq catégories : avant 6, 12, 18, 24 et 30 mois, pour suggérer le temps idéal de l’intervention chirurgicale affectant le résultat et comparer les deux groupes. Résultats En tout, 74 % des patients formèrent le groupe de réussite et 26 %, le groupe d’échec. Il n’y avait pas de différence statistiquement significative de durée du désalignement entre les deux groupes (p=0,91). La durée moyenne du désalignement était de 16,7 mois dans le groupe de réussite et de 20,1 mois dans le groupe d’échec, sans écart significatif (p=0,52). Il y avait quatre patients (14 %) ayant une durée de désalignement de 24 mois ou plus dans le groupe de réussite et cinq (50 %) dans celui de l’échec; l’écart était statistiquement significatif (p=0,024). Ainsi, avec une durée de désalignement allant jusqu’à 24 mois comme niveau de référence, les chances de réussite diminuent significativement en 24 mois, avec le modèle de régression logistique multiple entrainant une estimation de risque d’échec 6 fois plus élevé (OR-6,25, p-0,024). DP= Dioptries Prismatiques Conclusions Le résultat chirurgical postopératoire a été influencé par la durée du désalignement, plutôt que par l’âge au moment de la chirurgie. La chirurgie en-deçà de 24 mois de désalignement a affecté favorablement le pourcentage des patients qui avaient obtenu un résultat réussi du traitement de l’exotropie infantile.
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The clinical findings and management of two patients with congenital exotropia are described.
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The Roto-Extractor, designed by Nicholas Douvas, M.D., was used by the authors in 66 eyes for cataracts, secondary membranes, and persistent hyperplastic primary vitreous. The average age of the patients with congenital cataracts was 2.4 years, for traumatic cataracts 16.4 years. The pupil wal cleared well in 63 of these eyes. There was no vitreous to the wound in any of the eyes. Unplanned iridectomies and prolonged inflammation were the major complications.
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In order to prospectively study the development of strabismus in infancy, the ocular alignment of a large population of normal neonates was studied and follow-up examinations were obtained in a subset of these infants. The characteristic findings of congenital esotropia subsequently developed in three infants who were either orthotropic or exotropic at birth. Pathologic exotropia developed in two infants; both were exotropic at birth, but no more so than most normal neonates. In infants with congenital esotropia or pathologic exotropia, the characteristic deviation appears to develop between 2 and 4 months of age, a period during which normal infants are becoming increasingly orthotropic.
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Constant exotropia is uncommon during the first year of life. We retrospectively identified 13 patients with large, constant exotropia during the first year of life which required surgery. Bilateral lateral rectus muscle recessions were done in all 13 cases. Only two patients have required reoperation. The clinical characteristics and management of this unusual condition are similar to those of infantile esotropia.
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Essential infantile esotropia is an early acquired, not a congenital, condition, although congenital factors may favor its development between the ages of 3 and 6 months. It must be distinguished from other forms of esotropia with an onset between birth and the first six months of life. The cause of essential infantile esotropia remains unknown, but advances in our knowledge can be expected from the rapidly emerging discipline of infant psychophysics. In analyzing treatment results, a clear distinction must be made between normal, subnormal, and anomalous forms of binocular cooperation. While complete restoration of normal binocular function is rarely, if ever, achieved, anomalous binocular cooperation has many functional advantages over suppression or diplopia and should not be disturbed by overzealous treatment. Subnormal binocular vision is considered to be an optimal, microtropia a desirable, and a residual small angle heterotropia an acceptable end stage of surgical therapy. In a study of 358 surgically treated patients with a documented onset of essential infantile esotropia before age 6 months, subnormal binocular vision was present in 71 (20%), a microtropia in 25 (7%), and a small angle esotropia or exotropia in 140 (39%) of the patients. Surgical alignment before completion of the second year of life improved the chances for an optimal treatment result.(ABSTRACT TRUNCATED AT 250 WORDS)
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The term congenital esotropia has been challenged for many years. The basis of this challenge is that the deviation is not confirmed connatally. However, the term congenital esotropia is valid based on clinical observations and is easily separated from other forms of acquired esotropia.
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In an attempt to learn whether esotropia is present at birth or develops later in infancy, we observed 1,219 alert infants in a normal newborn nursery at a city hospital. Of these, 593 (48.6%) had orthotropic findings; 398 (32.7%) had exotropia, 40 (3.2%) had esotropia (intermittent in 17 with 14 varying between esotropia and exotropia and nine with a variable esotropia), and 188 (15.4%) were not sufficiently alert to permit classification. No infant displayed typical signs of congenital esotropia. We concluded that congenital-infantile esotropia is not connatal but rather develops in the first few weeks or months after birth.
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Exotropia is uncommon in healthy children between 6 months and 1 year old. The charts of patients treated in our practice between January 1980 and August 1994 were reviewed for a diagnosis of infantile exotropia. All of them had an exodeviation during the first year of life. Children with neurologic defects, prematurity, trauma, craniofacial syndromes, or orbital abnormalities or ocular defects that would reduce vision were eliminated. Sixty-six healthy patients with normal eyes had an exodeviation of 15 prism diopters (delta) or more that persisted through the first year of life. Fifty-four were eliminated because the diagnosis had not been confirmed by a pediatric ophthalmologist before they were 1 year old or they had not been followed for more than 4 years. The 12 remaining patients were followed for at least 4 years (mean, 7.9 years). The mean age at the first examination was 7.8 months (range, 4 to 12 months). On early evaluation, exotropia was intermittent in four and constant in eight. Three had amblyopia. Ten required surgical correction. Exotropia was corrected with one operation in six patients; four required additional procedures, mostly to correct oblique muscle overaction and dissociated vertical deviation (DVD). At the most recent visit, all 12 patients had equal visual acuity in both eyes and satisfactory ocular alignment. Five had fusion at distance and near, but only two had stereo acuity of 100 seconds of arc or better. Infantile exotropia is rare. But, like patients with infantile esotropia, those with exotropia can be expected to have good visual acuity but unstable ocular alignment. Also, as with early-onset esotropia, although surgical intervention is usually required, high levels of binocular function develop in some patients with exotropia. Oblique muscle overaction and DVD are common, often becoming manifest by the first year of age. Unlike infantile esotropia, nystagmus is rare.
Article
Exotropia in infancy is believed to be associated with an increased prevalence of neurologic, ocular, and craniofacial abnormalities; however, the prevalence of coexisting ocular and systemic disease in these patients is unknown. In this study, the prevalence of ocular disease and systemic illness was determined in patients diagnosed with exotropia in infancy. Observational comparative case series. Medical records of 70 patients diagnosed with exotropia in the first year of life were reviewed and compared with records of 136 patients diagnosed with esotropia before 1 year of age. Patients with no disorders (other than latent nystagmus, dissociated vertical deviation, or oblique muscle overaction) were grouped as "simple" strabismus. Patients with systemic disorders (including prematurity, neurologic disease, and genetic disease) and patients with ocular disorders (including congenital nystagmus, other strabismus, ptosis, and any condition associated with loss of vision [except amblyopia]) were grouped as "complex" strabismus. Prevalence of coexisting systemic and ocular disorders. The demographics, strabismus measurements, and types of coexisting disease in the simple and complex groups were compared. A high percentage of both exotropia (67%) and esotropia (49%) patients had a coexisting ocular or systemic abnormality. Exotropia patients with a constant strabismus were more likely to have coexisting ocular or systemic disease than those with an intermittent strabismus. Smaller angles of exotropia or esotropia were associated with a higher likelihood of coexisting ocular or systemic diseases. Systemic disorders were found more frequently than ocular disorders in both the exotropia and esotropia groups. In 25% of all patients referred for evaluation of strabismus, an additional ocular or systemic abnormality was discovered by the ophthalmologist. Patients presenting to a university hospital-based practice in the first year of life with exotropia were more likely than those presenting with esotropia to have coexisting ocular and systemic disease. Both groups had a notably high prevalence of associated disorders. The percentages measured in this population may not be applicable to other practices because of referral bias. However, clinicians should consider that children presenting with infantile exotropia and esotropia appear to be at risk for coexisting ocular or systemic disease.
Article
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