Adherence to home-based videogame treatment for amblyopia in children and adults.

Clinical relevance: Home-based videogame treatments are increasingly popular for amblyopia treatment. However, at-home treatments tend to be done in short sessions and with frequent disruptions, which may reduce the effectiveness of binocular visual stimulation. These treatment adherence patterns need to be accounted for when considering dose-response relationships and treatment effectiveness.Background: Home-based videogame treatments are increasingly being used for various sensory conditions, including amblyopia ('lazy eye'), but treatment adherence continues to limit success. To examine detailed behavioural patterns associated with home-based videogame treatment, we analysed in detail the videogame adherence data from the Binocular tReatment of Amblyopia with VideOgames (BRAVO) clinical trial (ACTRN12613001004752).Methods: Children (7-12 years), teenagers (13-17 years) and adults (≥ 18 years) with unilateral amblyopia were loaned iPod Touch devices with either an active treatment or placebo videogame and instructed to play for a total of 1-2 hours/day for six weeks at home. Objectively-recorded adherence data from device software were used to analyse adherence patterns such as session length, daily distribution of gameplay, use of the pause function, and differences between age groups. Objectively-recorded adherence was also compared to subjectively-reported adherence from paper-based diaries.Results: One hundred and five of the 115 randomised participants completed six weeks of videogame training. Average adherence was 65% (SD 37%) of the minimum hours prescribed. Game training was generally performed in short sessions (mean 21.5, SD 11.2 minutes), mostly in the evening, with frequent pauses (median every 4.1 minutes, IQR 6.1). Children played in significantly shorter sessions and paused more frequently than older age groups (p < 0.0001). Participants tended to over-report adherence in subjective diaries compared to objectively-recorded gameplay time.Conclusion: Adherence to home-based videogame treatment was characterised by short sessions interspersed with frequent pauses, suggesting regular disengagement. This complicates dose-response calculations and may interfere with the effectiveness of treatments like binocular treatments for amblyopia, which require sustained visual stimulation.

Surgical interventions for infantile nystagmus syndrome.

BACKGROUND: Infantile nystagmus syndrome (INS) is a type of eye movement disorder that can negatively impact vision. Currently, INS cannot be cured, but its effects can potentially be treated pharmacologically, optically, or surgically. This review focuses on the surgical interventions for INS. Despite the range of surgical interventions available, and currently applied in practice for the management of INS, there is no clear consensus, and no accepted clinical guidelines regarding the relative efficacy and safety of the various treatment options. A better understanding of these surgical options, along with their associated side effects, will assist clinicians in evidence-based decision-making in relation to the management of INS. OBJECTIVES: To assess the efficacy and safety of surgical interventions for INS. SEARCH METHODS: We searched CENTRAL, MEDLINE Ovid, Embase Ovid, ISRCTN registry, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) to 3 July 2020, with no language restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) studying the efficacy and safety of surgical options for treating INS. DATA COLLECTION AND ANALYSIS: Our prespecified outcome measures were the change from baseline in: binocular best-corrected distance visual acuity; head posture; amplitude, frequency, intensity, and foveation period durations of the nystagmus waveform; visual recognition times; quality of life and self-reported outcome measures; incidence of adverse effects with a probable causal link to treatment; and permanent adverse effects after surgery. Two review authors independently screened titles and abstracts and full-text articles, extracted data from eligible RCTs, and judged the risk of bias using the Cochrane tool. We reached consensus on any disagreements by discussion. We summarised the overall certainty of the evidence using the GRADE approach. MAIN RESULTS: We only identified one eligible RCT (N = 10 participants), undertaken in India. This trial randomised participants to receive either a large retro-equatorial recession of the horizontal rectus muscle of 9 mm on the medial rectus and 12 mm on the lateral rectus, or a simple tenotomy and resuturing of the four horizontal rectus muscles. We did not identify any RCTs comparing a surgical intervention for INS relative to no treatment. In the single eligible RCT, both eyes of each participant received the same intervention. The participants' age and gender were not reported, nor was information on whether participants were idiopathic or had sensory disorders. The study only included participants with null in primary position and did not explicitly exclude those with congenital periodic alternating nystagmus. The study did not report funding source(s) or author declaration of interests. The evaluation period was six months. We judged this study at low risk for sequence generation and other sources of bias, but at high risk of bias for performance and detection bias. The risk of bias was unclear for selection bias, attrition bias, and reporting bias. There is very uncertain evidence about the effect of the interventions on visual acuity and change in amplitude, frequency, and intensity of the nystagmus waveform. We were unable to calculate relative effects due to lack of data. None of the participants in either intervention group reported adverse effects at six-month follow-up (very low-certainty evidence). There was no quantitative data reported for quality of life, although the study reported an improvement in quality of life after surgery in both intervention groups (very low-certainty evidence). Change in head posture, foveation period durations of the nystagmus waveform, visual recognition times, and permanent adverse effects after surgery were not reported in the included study. We judged the certainty of the evidence, for both the primary and secondary efficacy outcomes, to be very low. Due to a lack of comprehensive reporting of adverse events, there was also very low-certainty of the safety profile of the evaluated surgical interventions in this population. As such, we are very uncertain about the relative efficacy and safety of these interventions for the surgical management of INS. AUTHORS' CONCLUSIONS: This systematic review identified minimal high-quality evidence relating to the efficacy and safety of surgical interventions for INS. The limited availability of evidence must be considered by clinicians when treating INS, particularly given these procedures are irreversible and often performed on children. More high-quality RCTs are needed to better understand the efficacy and safety profile of surgical interventions for INS. This will assist clinicians, people with INS, and their parents or caregivers to make evidence-based treatment decisions.

Why bilateral medial rectus recession fails? Factors associated with early repeated surgery.

BACKGROUND: To explore the risk factors for failure of bilateral medial rectus muscle recession (BMR) for esotropia. METHODS: We reviewed 171 consecutive patients with esotropia who underwent bilateral medial rectus muscle recession as a primary procedure from January 2009 to December 2011. Patients with infantile, partially accommodative and acquired esotropia were included. We compared patients who required more than one surgery to patients who only had one operation. RESULTS: A total of 171 patients (89 males, 52%, mean age 5.1 ± 6.0 years, range 0.4-51 years) fulfilled the inclusion criteria and comprised the study population. Mean follow-up period was 17.4 ± 15.5 months (range 1-65 months). A second strabismus surgery was performed in 17 (9.9%) cases within a mean time of 11.7 ± 9.2 months (range 0.4-27.7 months) from the initial surgery. Univariate analysis demonstrated that in patients younger than 1 year the odds ratio (OR) of failure was 4.00 (95% CI 1.12-14.35, p = 0.033) and for patients older than 7 years the OR of surgical failure was 3.27 (95% CI 1.10-9.76, p = 0.033). In addition, patients with esotropia > 60 prism diopters (PD) had a trend towards needing further surgery (OR = 3.91, 95% CI 0.93-16.44, p = 0.063). A multivariate model of regression revealed that age and angle of esotropia > 60 PD remained significant risk factors for requiring additional surgeries. CONCLUSIONS: In our cohort of patients who underwent BMR for esotropia, a large angle of esotropia and age were associated with failure of surgery and need for reoperation.

Single Muscle Transposition in the Management of Monocular Elevation Deficiency.

Monocular elevation deficiency is characterized by the inability to elevate one eye in abduction, adduction, and primary gaze. To date, various operations, including Knapp's procedure, have been used in the management of hypotropia associated with this condition. However, single muscle transposition has only recently been described as a feasible alternative, offering a number of advantages over other techniques. In particular, it reduces the risk of anterior segment ischemia and allows for an inferior rectus recession to occur simultaneously as is often required, thus avoiding the need for staged operations. It also facilitates a wider range of management options to correct for associated horizontal deviation. We present a case detailing the use of single muscle transposition in the management of monocular elevation deficiency and in doing so confirm the utility of this novel technique.

Optical treatment of amblyopia in older children and adults is essential prior to enrolment in a clinical trial.

PURPOSE: Optical treatment alone can improve visual acuity (VA) in children with amblyopia, thus clinical trials investigating additional amblyopia therapies (such as patching or videogames) for children require a preceding optical treatment phase. Emerging therapies for adult patients are entering clinical trials. It is unknown whether optical treatment is effective for adults with amblyopia and whether an optical correction phase is required for trials involving adults. METHODS: We examined participants who underwent optical treatment in the Binocular Treatment for Amblyopia using Videogames (BRAVO) clinical trial (ANZCTR ID: ACTRN12613001004752). Participants were recruited in three age groups (7 to 12, 13 to 17, or ≥18 years), and had unilateral amblyopia due to anisometropia and/or strabismus, with amblyopic eye VA of 0.30-1.00 logMAR (6/12 to 6/60, 20/40 to 20/200). Corrective lenses were prescribed based on cycloplegic refraction to fully correct any anisometropia. VA was assessed using the electronic visual acuity testing algorithm (e-ETDRS) test and near stereoacuity was assessed using the Randot Preschool Test. Participants were assessed every four weeks up to 16 weeks, until either VA was stable or until amblyopic eye VA improved to better than 0.30 logMAR, rendering the participant ineligible for the trial. RESULTS: Eighty participants (mean age 24.6 years, range 7.6-55.5 years) completed four to 16 weeks of optical treatment. A small but statistically significant mean improvement in amblyopic eye VA of 0.05 logMAR was observed (S.D. 0.08 logMAR; paired t-test p < 0.0001). Twenty-five participants (31%) improved by ≥1 logMAR line and of these, seven (9%) improved by ≥2 logMAR lines. Stereoacuity improved in 15 participants (19%). Visual improvements were not associated with age, presence of strabismus, or prior occlusion treatment. Two adult participants withdrew due to intolerance to anisometropic correction. Sixteen out of 80 participants (20%) achieved better than 0.30 logMAR VA in the amblyopic eye after optical treatment. Nine of these participants attended additional follow-up and four (44%) showed further VA improvements. CONCLUSIONS: Improvements from optical treatment resulted in one-fifth of participants becoming ineligible for the main clinical trial. Studies investigating additional amblyopia therapies must include an appropriate optical treatment only phase and/or parallel treatment group regardless of patient age. Optical treatment of amblyopia in adult patients warrants further investigation.

Effectiveness of a Binocular Video Game vs Placebo Video Game for Improving Visual Functions in Older Children, Teenagers, and Adults With Amblyopia: A Randomized Clinical Trial.

Importance: Binocular amblyopia treatment using contrast-rebalanced stimuli showed promise in laboratory studies and requires clinical trial investigation in a home-based setting. Objective: To compare the effectiveness of a binocular video game with a placebo video game for improving visual functions in older children and adults. Design, Setting, and Participants: The Binocular Treatment of Amblyopia Using Videogames clinical trial was a multicenter, double-masked, randomized clinical trial. Between March 2014 and June 2016, 115 participants 7 years and older with unilateral amblyopia (amblyopic eye visual acuity, 0.30-1.00 logMAR; Snellen equivalent, 20/40-20/200) due to anisometropia, strabismus, or both were recruited. Eligible participants were allocated with equal chance to receive either the active or the placebo video game, with minimization stratified by age group (child, age 7 to 12 years; teenager, age 13 to 17 years; and adult, 18 years and older). Interventions: Falling-blocks video games played at home on an iPod Touch for 1 hour per day for 6 weeks. The active video game had game elements split between eyes with a dichoptic contrast offset (mean [SD] initial fellow eye contrast, 0.23 [0.14]). The placebo video game presented identical images to both eyes. Main Outcomes and Measures: Change in amblyopic eye visual acuity at 6 weeks. Secondary outcomes included compliance, stereoacuity, and interocular suppression. Participants and clinicians who measured outcomes were masked to treatment allocation. Results: Of the 115 included participants, 65 (56.5%) were male and 83 (72.2%) were white, and the mean (SD) age at randomization was 21.5 (13.6) years. There were 89 participants (77.4%) who had prior occlusion. The mean (SD) amblyopic eye visual acuity improved 0.06 (0.12) logMAR from baseline in the active group (n = 56) and 0.07 (0.10) logMAR in the placebo group (n = 59). The mean treatment difference between groups, adjusted for baseline visual acuity and age group, was -0.02 logMAR (95% CI, -0.06 to 0.02; P = .25). Compliance with more than 25% of prescribed game play was achieved by 36 participants (64%) in the active group and by 49 (83%) in the placebo group. At 6 weeks, 36 participants (64%) in the active group achieved fellow eye contrast greater than 0.9 in the binocular video game. No group differences were observed for any secondary outcomes. Adverse effects included 3 reports of transient asthenopia. Conclusions and Relevance: The specific home-based binocular falling-blocks video game used in this clinical trial did not improve visual outcomes more than the placebo video game despite increases in fellow eye contrast during game play. More engaging video games with considerations for compliance may improve effectiveness. Trial Registration: anzctr.org.au Identifier: ACTRN12613001004752.

Conjunctival granuloma post pulley fixation suture.

Pulley fixation sutures to the medial rectus muscles have been used to manage variable-angle esotropia and convergence excess esotropia. Most techniques use a nonabsorbable suture. The posterior location of the sutures usually minimizes complications. We report a case of chronic conjunctival granuloma occurring after pulley fixation suture to the medial rectus muscle.

Binocular treatment of amblyopia using videogames (BRAVO): study protocol for a randomised controlled trial.

BACKGROUND: Amblyopia is a common neurodevelopmental disorder of vision that is characterised by visual impairment in one eye and compromised binocular visual function. Existing evidence-based treatments for children include patching the nonamblyopic eye to encourage use of the amblyopic eye. Currently there are no widely accepted treatments available for adults with amblyopia. The aim of this trial is to assess the efficacy of a new binocular, videogame-based treatment for amblyopia in older children and adults. We hypothesise that binocular treatment will significantly improve amblyopic eye visual acuity relative to placebo treatment. METHODS/DESIGN: The BRAVO study is a double-blind, randomised, placebo-controlled multicentre trial to assess the effectiveness of a novel videogame-based binocular treatment for amblyopia. One hundred and eight participants aged 7 years or older with anisometropic and/or strabismic amblyopia (defined as ≥0.2 LogMAR interocular visual acuity difference, ≥0.3 LogMAR amblyopic eye visual acuity and no ocular disease) will be recruited via ophthalmologists, optometrists, clinical record searches and public advertisements at five sites in New Zealand, Canada, Hong Kong and Australia. Eligible participants will be randomised by computer in a 1:1 ratio, with stratification by age group: 7-12, 13-17 and 18 years and older. Participants will be randomised to receive 6 weeks of active or placebo home-based binocular treatment. Treatment will be in the form of a modified interactive falling-blocks game, implemented on a 5th generation iPod touch device viewed through red/green anaglyphic glasses. Participants and those assessing outcomes will be blinded to group assignment. The primary outcome is the change in best-corrected distance visual acuity in the amblyopic eye from baseline to 6 weeks post randomisation. Secondary outcomes include distance and near visual acuity, stereopsis, interocular suppression, angle of strabismus (where applicable) measured at baseline, 3, 6, 12 and 24 weeks post randomisation. Treatment compliance and acceptability will also be assessed along with quality of life for adult participants. DISCUSSION: The BRAVO study is the first randomised controlled trial of a home-based videogame treatment for older children and adults with amblyopia. The results will indicate whether a binocular approach to amblyopia treatment conducted at home is effective for patients aged 7 years or older. TRIAL REGISTRATION: This trial was registered in Australia and New Zealand Clinical Trials Registry ( ACTRN12613001004752 ) on 10 September 2013.

Fixation-linked nondissociated hypotropia: a report of 3 cases.

Fixation-linked hypotropia, or hypotropic dissociated vertical deviation, is a rare but well-defined ocular motility disorder characterized by a slow downward drift of a poor-seeing eye when the other eye is fixating on a distant target. It can be successfully treated with a large recession or recession-resection of the inferior rectus muscle. We report 3 cases of fixation-linked nondissociated hypotropia with unilateral high myopia and amblyopia presenting with intermittent hypotropia of the worse-seeing eye when the dominant eye was fixating on a distant target and a hypertropia of the dominant eye when the poorer-seeing eye was made to fix. We discuss the surgical management of one of these patients.

Assessing abnormal head posture: a new paradigm.

PURPOSE OF REVIEW: We aim to give a systematic approach on how to assess the cause of a patient's abnormal head posture (AHP). RECENT FINDINGS: Over the decades, many important clinical observers and teachers have described diagnostic techniques for patients with AHP. Recently, Wong has added a new set of office-based diagnostic criteria that expand and solidify the office assessment of AHP. SUMMARY: We describe old and new, well known and poorly known office techniques for the assessment of AHP.

Medial rectus muscle pulley posterior fixation sutures in accommodative and partially accommodative esotropia with convergence excess.

BACKGROUND: The use of medial rectus pulley posterior fixation sutures to treat esotropia with convergence excess has limited support in the literature. We describe our results using this technique to treat patients with large near-distance disparities. METHODS: We retrospectively analyzed records of patients with accommodative or partially accommodative esotropia and convergence excess 13(Δ) or greater treated with bilateral medial rectus muscle recessions augmented by pulley posterior fixation. Surgical doses of recessions were calculated for the mean of distance and near deviations. Primary outcome measures were ocular alignment at distance and near and near-distance disparity. RESULTS: A total of 26 patients were identified by the record review. Mean age at surgery was 5.4 years (range, 1.8-11.0 years) and mean follow-up time 12.7 months (range, 1.0-37.6 months). Mean preoperative distance esotropia was 22.9(Δ) (range, 0(Δ)-53(Δ)), with a mean near-distance disparity of 26.4(Δ) (range, 13(Δ)-53(Δ)). At 1 to 3 months postoperatively, mean distance deviation was 0.5(Δ) exotropia (range, 18(Δ) exotropia to 12(Δ) esotropia), with a statistically significant decrease in mean near-distance disparity to 4.5(Δ) (range, 0(Δ)-26(Δ); P < 0.001). Three-quarters of patients (77%) achieved 0(Δ) to 9(Δ) esotropia at 1 to 3 months, with 4 overcorrections for distance and 2 undercorrections for distance and near. At final follow-up 2 patients had persistent exotropia less than 10(Δ). CONCLUSIONS: Augmentation of bilateral medial rectus recessions with pulley posterior fixation resulted in a significant decrease in near-distance disparity in this group of patients with accommodative and partially accommodative esotropia and convergence excess, with a low rate of persistent overcorrection for distance.

Lateral orbitotomy in the management of challenging exotropia.

The authors present an unorthodox surgical approach to reach the posterior segment of the lateral rectus muscle through a lateral orbitotomy and to manage difficult cases of recurrent exotropia. A review of the records of two patients with recurrent exotropia was done. After an anterior approach had been demonstrated to be inadequate due to shortening or fibrosis of the anterior part of this muscle following repeated surgeries, both patients underwent a lateral orbitotomy to reach the posterior segment of the lateral rectus muscle. Both patients achieved satisfactory ocular alignment following surgery with stable results, showing that this approach is a safe and effective surgical procedure.

Vestibular, saccadic and fixation abnormalities in genetically confirmed Friedreich ataxia.

Friedreich ataxia (FRDA), the commonest of the inherited ataxias, is a multisystem neurodegenerative condition that affects ocular motor function. We assessed eye movement abnormalities in 20 individuals with genetically confirmed FRDA and compared these results to clinical measures. All subjects were assessed with infrared oculography. Fifteen individuals underwent a full protocol of eye movement recordings. Ten subjects were analysed using two-dimensional scleral coil equipment and five using three-dimensional scleral coil recording equipment. We also recorded visual quality of life, Sloan low contrast letter acuity and Friedreich Ataxia Rating Scale scores to compare to the visual measures. Whilst saccadic velocity was essentially normal, saccadic latency was prolonged. The latency correlated with clinical measures of disease severity, including the scores for the Friedreich Ataxia Rating Scale and the Sloan low contrast letter acuity tests. Fixation abnormalities consisting of square wave jerks and ocular flutter were common, and included rare examples of vertical square wave jerks. Vestibular abnormalities were also evident in the group, with markedly reduced vestibulo-ocular reflex gain and prolonged latency. The range of eye movement abnormalities suggest that neurological dysfunction in FRDA includes brainstem, cortical and vestibular pathways. Severe vestibulopathy with essentially normal saccadic velocity are hallmarks of FRDA and differentiate it from a number of the dominant spinocerebellar ataxias. The correlation of saccadic latency with FARS score raises the possibility of its use as a biomarker for FRDA clinical trials.

Oxybutynin-associated esotropia.

A 5-year-old girl with previously unrecognized hyperopia of approximately +3.00 D developed esotropia while being treated with oxybutynin for enuresis. The esotropia disappeared with cessation of oxybutynin and correction of her hyperopia. When the hyperopic correction was removed, she had a small esophoria. The esotropia was presumably triggered by the anticholinergic effect of oxybutynin, which reduced the ability to accommodate. The increased accommodative effort for vision generated an esotropia as a result of the accommodative convergence/accommodation ratio.

Botulinum toxin in the treatment of strabismus. A review of its use and effects.

Botulinum Toxin as a medical therapy was introduced by Dr Alan Scott more than 20 years ago. The first clinical applications of Botulinum Toxin type A (BT-A) were for the treatment of strabismus and for periocular spasms. Botulinum Toxin type A is often effective in small to moderate angle convergent strabismus (esotropia) of any cause, and may be an alternative to surgery in these cases. Botulinum Toxin type A may have a role in acute or chronic fourth and sixth nerve palsy, childhood strabismus and thyroid eye disease. The use of BT-A for strabismus varies enormously in different cities and countries for no apparent reason. Botulinum Toxin type A may be particularly useful in situations where strabismus surgery is undesirable. This may be in elderly patients unfit for general anaesthesia, when the clinical condition is evolving or unstable, or if surgery has not been successful. Botulinum Toxin type A can give temporary symptomatic relief in many instances of bothersome diplopia irrespective of the cause. Ptosis and acquired vertical deviations are the commonest complications encountered. Vision-threatening complications are rare. Repeated use of BT-A is safe.

Chiari 1 malformation presenting as strabismus.

INTRODUCTION: Strabismus has been previously reported as a rare presenting feature of the Type 1 Chiari malformation. CASE REPORTS: We report a case series of twelve patients with Chiari 1 malformations with either strabismus or diplopia as part of their initial presentation. Ten patients had diplopia at the time of presentation, while 2 young children (ages 2 and 6) presented with esotropia without complaints of diplopia. Of the 10 patients with diplopia, 7 were constantly or frequently tropic while 3 had symptomatic phorias. One or more unusual features of the strabismus led to further investigations and the diagnosis of Chiari in these patients. The most common oculomotor disturbance was a comitant esotropia. Most patients were managed with prism glasses. One patient had strabismus surgery as primary treatment with early orthotropia. Three patients underwent neurosurgical decompression, with minimal improvement of their strabismus; one of these underwent subsequent successful strabismus surgery. CONCLUSIONS: Chiari 1 malformation may present with strabismus or diplopia as the major finding. Associated neurological features may be nonspecific (e.g., headache), subtle (e.g., gaze-evoked nystagmus), or delayed. Although neurosurgery may be required in some cases, primary strabismus management (surgical or prismatic correction) can be successful, particularly when strabismus is the lone (or sole specific) finding.

Refractive surgery and strabismus.

This review discusses the potential for strabismic complications after refractive surgery for hyperopia, myopia, anisomyopia, astigmatism and monovision, and how to avoid these complications. Guidelines are given for assessing patients with strabismus seeking refractive surgery. Screening tests are suggested that lead to stratification of refractive surgery patients into different risk groups each warranting a different intensity of evaluation.