To assess the accuracy of Plusoptix S12-C photoscreener in detecting amblyogenic risk factors in children aged 6 months to 6 years in remote areas of South India

Purpose:To assess the screening accuracy of a novel fourth generation, handheld Plusoptix S12 C photo screener in detecting amblyogenic risk factors in children aged 6 months to 6 years in remote areas of South India.Methods:In this cross sectional study, 381 children aged 6 months to 6 years were screened by a trained fieldworker in Anganwadis and schools using the Plusoptix photoscreener. This was followed by complete ophthalmic evaluation including retinoscopy, subjective refraction, and strabismus evaluation by an optometrist and an orthoptist. All children further underwent complete ocular examination by the senior pediatric ophthalmologist for validation of the results.Results:A total of 367 children were included in the study. The sensitivity and specificity of the photo screener were found to be 86.76% and 82.27%, respectively. Positive Predictive Value, Negative Predictive Value, and Receiver Operative Characteristics were 52.67%, 96.47%, and 83.11%, respectively. In subgroup younger than 3 years, sensitivity and specificity was 89.19% and 81.18%, respectively. Myopic astigmatism was the most common amblyogenic risk factor in our study group.Conclusion:In India, with a lack of adequate healthcare professionals and poor health-seeking behavior; photo screeners can play an important role. We recommend the use of photo screeners for screening children as young as 6 months, especially in remote low-resource settings. This will help in expanding reliable eye care services to previously underserved areas.     

A Comparison of Referral Criteria used by the PlusoptiX Photoscreener

Abstract

Purpose: To evaluate the sensitivity, specificity, and predictive value of 7 different referral criteria used for the plusoptiX photoscreener on the same cohort of children.

Methods: Retrospective chart review of patients presenting to a pediatric ophthalmology clinic who underwent plusoptiX photoscreening as part of a comprehensive examination. We applied multiple referral criteria from previously published studies as well as the manufacturer’s criteria in order to calculate specificity, sensitivity, and predictive value differences between the various referral criteria. We compared all criteria to the results of a pediatric ophthalmology examination based upon the 2003 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) criteria, as well as the newly accepted revision of the AAPOS referral criteria.

Results: 109 children were examined with a thorough pediatric ophthalmic exam and with the plusoptiX photoscreener. Of these, 58 (53%) were confirmed to demonstrate amblyopia risk factors, according to 2003 AAPOS criteria. The plusoptiX referral criteria were adjusted to match 7 different published plusoptiX referral paradigms so that the differing referral paradigms could be analyzed for sensitivity and specificity. When comparing the differing plusoptiX referral paradigms to 2003 AAPOS criteria, the sensitivity/specificity of the 7 different paradigms were respectively: Matta/Silbert 98%/80%, Arthur (2) 67%/96%, Arnold 81%/96%, Arthur 81%/92%, PediaVision 80%/94%, plusoptiX 98%/41%, AAPOS 74%/86%. When comparing the 7 differing referral paradigms to the newly approved (2013) AAPOS criteria, the sensitivity/specificity were respectively: Matta/Silbert 98%/68%, Arthur (2) 73%/92%, Arnold 92%/90%, Arthur 86%/85%, PediaVision 90%/92%, plusoptiX 98%/35%, AAPOS 87%/87%.

Conclusion: There are multiple referral criteria available for the plusoptiX photoscreener. Screening programs need to evaluate their own requirements with respect to desired sensitivity and specificity and decide on the most appropriate referral criteria for their program. The “Arnold” criteria is the best at maximizing sensitivity and specificity utilizing the 2003 “AAPOS” criteria and the “Arnold” and “PediaVision” were best at maximizing sensitivity and specificity for the newly accepted AAPOS referral criteria. Screening programs will need to decide the level of sensitivity and specificity that they wish to obtain, but for most screening programs the “Arnold” criteria may be preferred.     

Accuracy of Plusoptix S04 in children and teens

Objective: To compare refraction measurements of young patients obtained using Plusoptix S04 with those obtained using cycloplegic retinoscopy.Design: Cohort study.Participants: Data were collected from 64 patients (128 eyes), aged 2–19 years.Methods: All eyes underwent photorefraction using Plusoptix S04 with or without cycloplegia and cycloplegic retinoscopy. Eyes with a maximum spherical and cylinder range of −7.00 to +5.00 were excluded from the study.Results: The difference in spherical equivalents between Plusoptix S04 without cycloplegia and cycloplegic retinoscopy was more than ± 0.50 D in 70.2% of the eyes. In 100 eyes (78.1%), photorefraction underestimated the hyperopic refractive error. The cylinder powers determined by Plusoptix S04 and cycloplegic retinoscopy were similar. The difference in the spherical equivalents between Plusoptix S04 with cycloplegia and cycloplegic retinoscopy was + 0.50 D in 89.8% of the eyes. In 96 eyes (75%), photorefraction with cycloplegia overestimated the hyperopic refractive error. The difference in cylindrical power determined using Plusoptix S04 with cycloplegia and cycloplegic retinoscopy was statistically significant (paired ttest, p = 0.009).Conclusions: The statistically significant difference in spherical equivalent values obtained using Plusoptix S04 with or without cycloplegia and cycloplegic retinoscopy suggests that Plusoptix S04 is more in evaluating the cylinder power and axis in young patients. Our results also suggest that Plusoptix S04 is not an accurate tool to estimate the refraction in children.     

Strabismus surgery outcomes after scleral buckling procedures for retinal reattachment

Abstract

Objective: To investigate the outcomes of strabismus surgery in patients with a prior history of a scleral buckling procedure for retinal reattachment.

Methods: We reviewed the medical records of 18 patients who underwent strabismus surgery following a scleral buckling procedure and investigated the effect of multiple variables on postoperative alignment after strabismus surgery including gender, age, surgeon, number of strabismus surgeries, adjustable suture use, previous pars plana vitrectomy, preoperative best-corrected visual acuity, and scleral buckle removal. Outcomes were considered successful if there was ≤10 prism diopters (PD) residual horizontal and/or ≤4 PD residual vertical deviations. Statistical analyses were performed using Fisher’s exact test, Mann-Whitney test, and nominal logistic regression.

Results: Success using our criteria of motor alignment was achieved in 6 of 18 eyes (33%). A higher rate of success was found in the scleral buckle removal group (success with buckle removal, 62.5%; success without buckle removal, 10.0%; p?=?0.04). Nominal logistic regression analysis showed scleral buckle removal was the most significant factor associated with successful surgical alignment (p?=?0.03; odds ratio?=?16.67). Although the success rate was higher in the adjustable suture group (50% in adjustable group vs 14.3% in non-adjustable group: Fisher’s exact test, p?=?0.30), this difference was not statistically significant. No retinal redetachments occurred after scleral buckle removal.

Conclusions: These results suggest that scleral buckles can be safely removed in selected patients with strabismus following retinal reattachment surgery and scleral buckle removal may improve ocular alignment following strabismus surgery.     

Effectivity of intraoperative adjustable suture technique in horizontal strabismus

AIM:To compare the long-term effectivity of intraoperative adjustable suture technique with traditional non-adjustable strabismus surgery.METHODS:Two hundred and thirty-three patients, who underwent strabismus surgery either with traditional procedures or one-stage intraoperative adjustable suture technique, were included in our long-term follow-up study. One hundred and eighteen patients were evaluated in traditional surgery group (TSG) and 115 who underwent adjustable suture were in the one-stage intraoperative adjustable surgery group (ASG). In this group 9 patients had paralytic strabismus and 16 had reoperations, 2 patients had restrictive strabismus related to thyroid eye disease. The mean follow up in the TSG was 26.2 months and it was 24.8 months in the ASG group.RESULTS:In patients with exotropia (XT) the mean correction of deviation for near fixation in ASG (32.4±13.2PD) and in TSG (26.4±8.2PD) were similar (P=0.112). The correction for distant fixation in ASG (33.2±11.4PD) and TSG (30.9±7.2PD) were not significantly different (P=0.321). In patients with esotropia (ET) even the mean correction of deviation for both near (31±12PD) and distant (30.6±12.8PD) fixations were higher in ASG than in TSG, for both near (28.27±14.2PD) and distant (28.9±12.9PD) fixations, the differences were not significant (P=0.346, 0.824 respectively). The overall success rate of XT patient was 78.9% in TSG and 78.78% in ASG, the difference was not significant (P=0.629). The success rates were 78.75% in TSG and 75.51% in ASG in ET patient, which was also not significantly different (P=0.821).CONCLUSION:Although patients in ASG had more complex deviation such as paralysis, reoperations and restrictive strabismus, success rates of this tecnique was as high as TSG which did not contain complicated deviation. One-stage intraoperative adjustable suture technique is a safe and effective method for cooperative patient who has complex deviation.     

Wright hang-back recession with fibrin glue compared with standard fixed suture recession for the treatment of horizontal strabismus

ObjectiveTo evaluate the clinical safety and efficacy of the novel Wright hang-back recession with fibrin glue for the treatment of horizontal strabismus.Study DesignRetrospective, case-controlled clinical study comparing surgical outcomes of the Wright hang-back rectus recession with fibrin glue (WHBG) versus standard fixed suture rectus recession (SFR).MethodsMedical records of all patients who underwent strabismus surgery by one strabismus surgeon between 2016 and 2018 for horizontal deviations only, including cases of WHBG (group 1) or SFR (group 2), were reviewed. Good surgical outcome was defined as a postoperative deviation ≤10 prism diopters (PD) at a minimum 2 months of follow-up.Results32 eyes of 17 patients underwent WHBG and 32 eyes of 17 patients underwent SFR; in each group, 35% had esotropia and 65% had exotropia. Mean preoperative deviations between groups were similar: esotropia 25.5 PD and exotropia 26.6 PD in WHBG; esotropia 28.3 PD and exotropia 23.8 PD in SFR. The mean postoperative deviation was <7 PD for both groups. Good surgical outcomes were similar between groups, 16/17 (94%) in WHBG and 15/17 (88%) in SFR, with no complications.ConclusionsWHBG was safe and effective with postoperative results similar to SFR. WHBG has an important advantage, eliminating the complication of retinal perforation that can occur with SFR while avoiding under- or overcorrection that can occur with traditional hang-back recession. This technique increases patient safety without sacrificing surgical outcomes and is especially useful in patients with thin sclera such as patients with high myopia or with difficult posterior exposure.     

Botulinum Toxin Treatment in Patients Up to 3 Years of Age Who Have Esotropic Duane Retraction Syndrome

ABSTRACT

Purpose: To report the results of botulinum toxin (BOTOX®, Allergan) type A (BTA) bilateral injection in the treatment of Duane retraction syndrome (DRS) type 1 in patients aged up to 3 years.

Methods: We studied the results of BTA bilateral injection in eight consecutive patients with DRS type 1 and esotropia in primary gaze. Average follow-up was 74?±?71 months. The main variables analyzed were horizontal and vertical deviation and face turn. Patients were anesthetized with nitrous oxide (N₂O). A mean dosage of 5.6?±?1.8?IU (range 2.5–7.5?IU) of botulinum toxin diluted in 0.9% saline solution was injected under electromyography control in each medial rectus muscle.

Results: Seven patients had one affected eye and one patient had bilateral involvement. The mean preoperative esotropia was 32?±?10 prism diopters (PD). Three patients (37.5%) had also a vertical deviation. All patients had face turn ranging between 15° and 45° before BTA injection. In the last follow-up, 4 patients were orthotropic (50%), 1 (12.5%) had 3 PD exotropia and 3 (37.5%) had esotropia averaging 25 PD mean. The 3 esotropic patients needed surgical correction. Vertical strabismus improved in 3 patients achieving complete resolution in one of these patients. Two patients, without vertical strabismus before the BTA injection, developed a 5-PD vertical deviation, one of them required surgery. Face turn improved in all patients.

Conclusion: Botulinum toxin injection is an alternative treatment for patients with DRS type 1 presents esotropia and face turn in children up to 3 years of age.     

Bupivacaine injection combined with recession of antagonist rectus muscle to treat sensory strabismus

Purpose: This study aims to evaluate the effect of bupivacaine injection at 1.5% combined with recession of the antagonist rectus muscle to treat sensory strabismus in adult patients.

Methods: Nine patients with a horizontal deviation, visual acuity of <20/60 in the worst-seeing eye, and no previous strabismus surgery were selected. Patients with vertical strabismus were excluded. Lateral rectus (LR) recession was performed in patients with exotropia and medial rectus (MR) recession in patients with esotropia according to Park’s Table, as modified by Wright. Bupivacaine 1.5 mL at 1.5% was injected in the antagonist of the recessed muscle. The patients were evaluated after 1, 7, 30, 60, 90, and 180 days of the procedure. Successful motor alignment was defined as within 10 prism diopters (PD) of orthophoria. Dose-response was considered as the total amount of correction, divided by recession performed in millimeters, associated with bupivacaine injection in the antagonist muscle.

Results: Of the patients, 44% (4/9) had a successful motor alignment. The mean correction for exotropia (n = 5) with a preoperative horizontal deviation of 50 ± 6.12 PD was 23 ± 14.4 PD with a dose-response of 2.6 PD/mm. For esotropia (n = 4), the mean correction of 21.25 ± 4.8 PD was achieved with a preoperative deviation of 28.7 ± 14.9 PD with a final dose-response of 5 PD/mm. All unsuccessful patients had a preoperative deviation of ≥45 PD.

Conclusion: Bupivacaine injection in the antagonist of a recessed extraocular muscle (EOM) appears to add an effect to the standard dose-response of a muscle recession. For patients with esotropia (<25 PD), a single MR recession combined with bupivacaine in the LR can produce a successful motor alignment. For patients with large horizontal strabismus (>45 PD), larger bupivacaine doses (volume and concentration) combined to larger recessions may be needed.     

Outcomes of a simplified,fixed surgical dosage calculation for uncomplicated,horizontal, concomitant strabismus in adults

Purpose:The aim of this study was to evaluate the outcomes of a simplified, fixed surgical dosage calculation for uncomplicated, horizontal, concomitant strabismus in adults.Methods:Outcomes analysis of a fixed-dose calculation method for uncomplicated, horizontal, concomitant strabismus in adults (≥18 years) wherein 1-mm recession/resection equals 2 PD for lateral rectus and 3 PD for medial rectus. This was a retrospective case series.Results:The mean age of the patients was 28.50 ± 8.43 years, the mean amount of preoperative deviation was 35.16 ± 9.97 PD, the mean expected correction was 36.26 ± 9.49 PD, and the mean correction achieved was 35.92 ± 10.74 PD. There were 22 monocular exotropias, six monocular esotropias, eight alternate divergent squints, and two alternate convergent squints. There were 20 cases of sensory strabismus (54.28%). There was no statistically significant difference between the expected correction and correction achieved (P = 0.519), meaning that our fixed-dose calculation method was effective. Thirty-five out of 38 patients had successful outcomes as per our criteria of less than 10-PD deviations from straight in primary position. Therefore, the success rate achieved by this procedure was 92.10%. There was no statistically significant correlation between age and the amount of deviation (P = 0.611)Conclusion:Our case series had a high postoperative success rate in terms of motor alignment. It is hoped that this simplified, fixed-dosage calculation method would help the numerous novice strabismus surgeons, make their starting steps easier and give them the confidence to do strabismus surgeries. They can modify the dosages later as per their own experiences.     

Factors Affecting Improvement of Stereopsis Following Successful Surgical Correction of Childhood Strabismus in Adults

ABSTRACT

Purpose: To evaluate the factors affecting improvement of stereopsis following successful surgical correction of childhood strabismus in adults.

Methods: In a prospective study, consecutive patients with childhood-onset, comitant, horizontal, constant strabismus; stereoacuity of more than 480 seconds of arc in TNO stereo test (absent stereopsis in TNO); and who had successful postoperative alignment (within 10 prism diopters [PD] of orthotropia) were enrolled. Postoperative stereopsis testing was performed using the TNO stereo test at 3 months after surgery.

Results: A total of 34 patients (20 exotropes and 14 esotropes) were included. The mean age at the time of surgery was 26.08?±?10.53 years (range, 14–53 years). Stereopsis was improved in 8 of 34 patients (23.5%). Postoperative alignment had influence on improvement of stereopsis; 38.1% of patients who had orthotropia gained stereopsis, whereas none of patients who had horizontal heterotropia (esotropia or exotropia) of 10 PD or less gained stereopsis (p?=?0.01). Misalignment of 10 years’ duration or longer did not preclude the development of postoperative stereoacuity (p?=?0.31). There was a statistically insignificant increase in improvement of stereopsis in nonamblyopic group (30.4%) compared with amblyopic group (9.1%) (p?=?0.22). Also, there was a statistically insignificant increase in improvement of stereopsis in exotropes (35%) compared with esotropes (7.1%) (p?=?0.1). The angle of preoperative deviation had no influence on improvement of stereopsis (p?=?0.44).

Conclusion: A postoperative correction of orthotropia was the only predictive factor for improvement of stereopsis in adults with childhood strabismus.     

Comparison of Surgical Success for Infantile Esotropia and Strabismus Associated with Neurological Impairment

Purpose: Surgery for strabismus associated with neurological impairment is assumed to have unsatisfactory results in comparison with other strabismus cases. The aim of this study is to compare the surgical success rates of infantile esotropia (IE) and strabismus associated with neurological impairment.

Methods: The records of 103 patients that received operations for IE and strabismus associated with neurological impairment between January 1994 and May 2014 were reviewed retrospectively. The angles of deviation and surgical success rates were evaluated at preoperative, 1-month postoperative, and 24-month postoperative visits.

Results: Forty-five patients received operations for strabismus associated with neurological impairment (25 patients with esotropia and 20 patients with exotropia) and 58 patients for IE. Mean preoperative angles of deviation in cases with neurological impairment were 42 prism diopters (PD) for esotropia, 44.7 PD for exotropia, and 44.4 PD for IE. One patient from each group had consecutive deviation at first visit, and at last visit, 3 patients with neurological impairment and 5 patients with IE had consecutive deviations. Surgical success rates at the end of the second year were 52% for esotropia and 50% for exotropia in patients with neurological impairment and 56.8% for IE cases.

Conclusion: This study was unable to find the differences between surgical success rates in IE and strabismus associated with neurological impairment.     

Functional and Motor Outcomes of Strabismus Surgery for Chronic Isolated Adult Sixth Nerve Palsy

Abstract

Abducens nerve palsy is the most common acquired ocular motor nerve palsy in adults. Chronic cases of abducens palsy often require surgical intervention to relieve disabling diplopia. The goal of this study was to identify factors associated with surgical outcomes in isolated abducens palsy. Medical records of all adult patients from 1988 to 2012 with abducens palsies who underwent strabismus procedures were retrospectively reviewed. Motor alignment, extraocular motility, and sensory outcomes were recorded. Success was defined as absence of diplopia without prisms or face turn, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Eighty-one patients (age range: 20–86 years) met inclusion criteria. Success was achieved in 58% of patients. Final success rates for abducens palsy were 50% for neoplastic, 59% traumatic, 57% for microvascular/unknown, and 67% for other central nervous system causes (p?>?0.05). Patients with an underlying neoplastic or traumatic aetiology required more than one strabismus procedure more often than those with microvascular/idiopathic or other central nervous system causes (48% vs. 24%; p?=?0.03). For complete abducens palsies, patients who underwent Hummelsheim-type procedures had a higher success rate than those who underwent a full-tendon vertical rectus muscle transposition. (78% versus 35%; p?=?0.049). Success rates for strabismus procedures in patients with abducens palsies are similar across all aetiologies. Frequency of re-operation is higher among those patients with neoplastic or traumatic aetiologies for their abducens palsies. Hummelsheim-type procedures have a higher success rate for complete abducens palsies than full-tendon vertical rectus transpositions.     

Amniotic membrane in the management of strabismus reoperations

Purpose

To reduce postoperative scar formation and to improve duction using amniotic membrane (AM) in strabismus reoperations.

Methods

A prospective study of interventional case series comprised of 14 patients with restrictive strabismus. Objective clinical findings (visual acuity, angle of deviations and degree of duction deficits) were recorded in both the pre- and post-operative periods. Strabismus surgery included the excision of adhesions and scar tissue, repositioning of extraocular muscles (according to the degree of deviations) and placement of two sheets, one between muscle and tenon and the other between muscle and sclera. Conjunctival recession with covering of the bare sclera using AM was also performed.

Results

The mean preoperative deviation of the patients was 34.3 prism diopters (PD) and mean post-operative deviation was 4.6 PD. The mean pre-operative duction deficit of the patients was 1.7; mean post-operative duction deficit was 0.2. Postoperatively all patients improved in relation to deviation and duction. Less than 8 PD deviations with no duction deficits were achieved in 12 (86 %) of the patients.

Conclusions

Amniotic membrane placement around the extraocular muscle improves the duction and decreases the residual angle of deviations by inhibiting postoperative scar formation.     

下斜肌肌腹转位术治疗轻度下斜肌亢进伴小度数垂直斜视

目的：观察下斜肌肌腹转位(IOBT)术在单眼下斜肌轻度亢进伴小度数垂直斜视中的应用效果。

方法：回顾性分析2019-09/2021-08在我院行IOBT术的患者,纳入标准为单眼下斜肌轻度亢进(2+及以下),并伴有轻度非共同性垂直斜视(4～9PD)。水平斜视按照常规手术量和方式设计,同期单侧下斜肌亢进眼行单眼IOBT术。观察手术前后水平斜视度、垂直斜视度、侧方注视位垂直斜视度、黄斑视盘夹角及下斜肌亢进程度等。

结果：纳入病例共16例16眼,年龄4～39岁。1例为先天性内斜视术后5a,单眼上斜肌轻度麻痹继发下斜肌功能亢进,余15例均为原发性下斜肌功能亢进伴水平斜视。随访时间为3～6mo。术前和术后平均下斜肌亢进程度分级分别为+2.00(2.00,2.00)级和0.00(0.00,0.00)级(Z=-3.704,P<0.001),平均改善2.00(1.25,2.00)级; 水平斜视度从术前69.13±25.86PD减少到术后2.75±2.59PD(t=9.929,P<0.001); 第一眼位垂直斜视从术前7.44±1.32PD减少到术后1.00±1.21PD(t=22.335,P<0.001),平均矫正上斜视为6.44±1.15PD; 侧方注视垂直斜视从术前12.44±2.73PD减少到术后3.00±2.13PD,平均矫正9.44±2.73PD(t=13.819,P<0.001)。黄斑中心凹-视盘中心夹角度数(FDA)术前为-8.85°±6.53°,术后为-6.49°±7.01°(t=-2.384,P<0.001),平均减少2.36°。未见术后过矫及下斜肌功能不足等并发症。

结论：IOBT术对矫正单侧轻度下斜肌亢进伴小度数垂直斜视是安全有效的。     

Long-term outcomes of strabismus surgery in Mobius sequence

ABSTRACT

Purpose: Mobius sequence is a rare disorder that results from underdevelopment of the sixth and seventh cranial nerves, with subsequent facial weakness and impairment of ocular abduction. Approximately half of the affected patients have esotropia with limitation of extraocular movements. This study retrospectively reviews the long-term outcome of strabismus surgery for such patients.

Methods: The long-term follow-up results in five children with Mobius sequence, who were observed after strabismus surgery for congenital esotropia, were analyzed.

Results: All patients had a limitation of abduction in both eyes. Preoperative esotropia ranged from 20 to 30 prism diopters (PD) (mean 27 PD). Patient age at surgery ranged from 4.5 to 14 months. Bilateral medial rectus muscle recession was performed in all cases, ranging from 4.0 to 6.5 mm. Inferior transposition of the medial rectus muscles was performed in two patients for treatment of V-pattern, and two patients also had surgery for vertical strabismus. Follow-up ranged from 4 to 19.5 years (mean 11.7 years). The final horizontal alignment was <8 PD in all patients, and all demonstrated some binocularity.

Conclusion: Bilateral medial rectus muscle recession is an effective treatment for esotropia associated with Mobius sequence, with good long-term stability.     

Successes and shortfalls of community Plusoptix photoscreening: results from the iSee study in Southwestern Ontario

ObjectiveThe purpose of this work is to provide the final results from a community-wide photoscreening program in Southwestern Ontario for children aged 18 to 72 months, and to estimate the prevalence of amblyogenic risk factors in this population.Study DesignProspective, multisite photoscreening program.Participants5959 children aged 18–72 months were recruited and screened in Southwestern Ontario at 210 locations over a period of 3 years and 4 months.MethodsOphthalmic screening examinations were performed with the Plusoptix S12 photoscreener. The threshold for the referral criteria used was the manufacturer's criteria on receiver operating characteristics 4.ResultsThe screening was negative in 5386 children (90.4%), positive in 403 (6.8%), and unreadable in 170 (2.9%); 42% of all screened children were ≤36 months old. The estimated amblyogenic risk factor prevalence of anisometropia was 4.0%, astigmatism was 3.1%, hyperopia was 1.1%, myopia was 0.4%, and strabismus was 0.4%. Of the 403 referred children, 99 (24.5%) completed a formal eye examination based on the responses returned to the study site.ConclusionsThis is the first Canadian study that provides data on amblyogenic risk factors based on a volunteer-led photoscreening program. Photoscreening is an effective screening tool, particularly for pre-school-aged children; however, the lack of mandatory follow-up to ensure that children receive proper treatment based on cycloplegic refraction reduces the efficacy of screening.     

Binocular Visual Rehabilitation in Paralytic Strabismus by Botulinum A Toxin Chemodenervation

PurposeTo investigate the effect of botulinum A toxin (BTXA) chemodenervation in paralytic strabismus patients without surgical correction.MethodsA retrospective chart review of 51 patients who were diagnosed as paralytic strabismus and underwent BTXA chemodenervation was performed. The patients were divided into four groups according to the cause of paralytic strabismus of vasculopathy, neoplasm, trauma, and idiopathic. They were also divided into two groups of early and late treatment according to the initiation time of BTXA chemodenervation after the onset of strabismus (3 months), and of the initial strabismus type of exotropia and esotropia. We investigated the changes of angle of deviation and diplopia after BTXA chemodenervation.ResultsThe average deviation of angles decreased by 25.2 prism diopter (PD) (35.1 to 9.9 PD) in total patients, and the overall success rate was 64.7% (33 by 51), and the there was no statistically significant difference in success rate between each group divided by the cause of paralytic strabismus. According to the treatment timing, the deviation of the angle decreased by 28.0 PD (36.8 to 8.8 PD) in the early treatment group, and 21.3 PD (33.5 to 12.2 PD) in late treatment group at the time of the last postinjective follow-up. According to the initial strabismus type, the average angle of deviation decreased by 20.3 PD (35.6 to 15.3 PD) in exotropia group by cranial nerve 3 palsy, and 24.4 PD (32.5 to 8.1 PD) in esotropia by cranial nerve 6 palsy.ConclusionsBTXA chemodenervation reduced the angle of deviation and the number of patients with diplopia regardless of the cause of paralytic strabismus. Early BTXA chemodenervation can be considered as the first treatment of choice in paralytic strabismus, especially in esotropia patients.     

Comparison of photorefraction,autorefractometry and retinoscopy in children

Photorefractive devices have been evaluated for their effectiveness in detecting anisometropia, hyperopia, myopia, and astigmatism. We investigated the reliability of Plusoptix S08, the newest photoscreener, and Topcon autorefractometer by comparing them with cycloplegic retinoscopy. Plusoptix S08, cycloplegic retinoscopy, and cycloplegic autorefractometer measurements for 235 eyes of 118 children (59 female, 59 male) with a mean age of 4.9 ± 2.6 and median age of 5 years (range 1–12) were conducted. The Plusoptix S08 produced the following mean (±SD) results—spherical 0.27 ± 1.64, cylindrical power ?0.81 ± 0.71, axis 89.73 ± 61.18, and spherical equivalent ?0.05 ± 1.61. The cycloplegic retinoscopy produced the following mean (±SD) results—spherical 0.12 ± 1.35, cylindrical power ?0.89 ± 0.71, axis 92.18 ± 68.39, and spherical equivalent ?0.15 ± 1.31. The cycloplegic autorefractometer produced the following mean (±SD) results—spherical 0.16 ± 1.44, cylindrical power ?0.88 ± 0.72, axis 90.86 ± 68.21, and spherical equivalent ?0.12 ± 1.41. This study has shown that cycloplegic autorefractometer and retinoscopy results are similar and Plusoptix S08 is a very safe, easy-to-use and reliable screening method of refraction, especially for ophthalmologists unskilled in retinoscopy. Plusoptix S08 is a useful tool for estimating refraction in patients for whom conventional autorefraction is not an option.     

Comparing the SureSight autorefractor and the plusoptiX photoscreener for pediatric vision screening

Purpose: Both the plusoptiX photoscreener photoscreener and the SureSight autorefractor can be used to objectively screen for amblyogenic risk factors in children. We compare the plusoptiX and the SureSight to a pediatric ophthalmology examination on a single cohort of children.

Methods: We performed a retrospective medical records review of 90 children. Each patient was screened with both the PlusoptiX A09 and SureSight devices on the same day as part of a comprehensive pediatric ophthalmic examination. The ages of the patients ranged from <1 to 17 years. All patients had a cycloplegic refraction on the day of their exam, or within the previous 6 months.

Results: Of the children reviewed, 71% had amblyopia risk factors. The plusoptiX demonstrated a sensitivity of 98% and a specificity of 88%. The SureSight demonstrated a sensitivity of 95% and a specificity of 65% utilizing the manufacturer’s criteria.

Conclusion: The SureSight and plusoptiX were both found to be reliable objective vision screening devices, though the plusoptiX did have a higher sensitivity and specificity than the SureSight using the manufacturer’s referral criteria. Using the Vision In Preschoolers Study (VIPS) referral criteria, the specificity of the SureSight improved but the sensitivity was reduced.     

Outcome of large angle exotropia treated by single stage adjustable strabismus surgery with monitored conscious anesthesia

Purpose:To evaluate the outcomes of large-angle exotropia by single-stage adjustable strabismus surgery (SSASS) under monitored conscious anesthesia.Methods:A prospective study was done in 33 patients above 14 years with ≥40 prism diopters (PD) of exotropia. All patients underwent SSASS under monitored conscious anesthesia (topical anesthesia plus intravenous sedation). For deviations of ≤55 PD, two horizontal rectus muscles, and for >55 PD, three rectus muscles were operated and a decision on adjustment/operating on an additional rectus muscle was taken after assessing the alignment. Monitored conscious anesthesia allowed us to check our results after surgery and plan further surgery/adjustment to achieve the desired alignment.Results:Mean preoperative deviation for distance was 52 ± 11.1 PD. The target alignment was achieved with the initial surgical plan in 10/21 patients with <55 PD exotropia and 4/12 patients with >55 PD exotropia, and one patient in each group needed adjustment. The remaining patients needed additional rectus muscle surgery. One patient with >55 PD exotropia needed both adjustment and additional rectus surgery. The success rate for distance correction was 85% at 6 months and 1 year. The overall success rate was 71% at 6 months. Percentage of patients with binocular single vision improved from 31% preoperatively to 78% by 6 months. Incidence of oculocardiac reflex was 6.1%.Conclusion:SSASS under monitored conscious anesthesia is a viable option for large-angle strabismus correction with good patient comfort and safety.