Adverse reactions to 1% cyclopentolate eye drops in children: an analysis using logistic regression models.

PURPOSE: To determine the frequency, symptoms and risk factors for adverse reactions to two-times instillation of 1% cyclopentolate in children. STUDY DESIGN: Prospective, observational study. METHODS: The subjects were 646 patients who underwent cycloplegic refraction with cyclopentolate (mean age; 7.0 ± 3.5 years, age range; 0-15 years). Five minutes after instillation of 0.4% oxybuprocaine hydrochloride, a 1% cyclopentolate eye drop was instilled twice, with an interval of 10 min. Fifty minutes later, two certified orthoptists evaluated adverse reactions using a questionnaire and interviewed the patients' guardians. The relationship between the adverse reaction rates and age, gender, additional instillation, complications of the central nervous system (CNS), time of day and season were analysed using binominal and polytomous logistic regression models. RESULTS: The overall frequency of adverse reactions was 18.3% (118/646 patients). The main symptoms included conjunctival injection (10.5%, 68/646), drowsiness (6.8%, 44/646) and facial flush (2.2%, 14/646). The odds ratio (OR) of conjunctival injection increased with patient's age (p < 0.05), in boys (p < 0.01) and in winter (p < 0.001). In contrast, the OR of drowsiness decreased with age (p < 0.001). Facial flush was observed mostly in children younger than 4 years. CNS complications were not a significant risk factor for any of the symptoms. CONCLUSIONS: Adverse reactions to 1% cyclopentolate eye drops were more frequent than previously expected, but all were mild and transient. The probability of each symptom was associated with a clear age-specific trend.

Risk factors for excessive postoperative exo-drift after unilateral lateral rectus muscle recession and medial rectus muscle resection for intermittent exotropia.

BACKGROUND: To detect significant factors associated with excessive postoperative exo-drift in young patients with intermittent exotropia who had undergone unilateral lateral rectus muscle recession and medial rectus muscle resection. METHODS: We retrospectively examined the records of 64 consecutive patients < 18 years old who underwent surgery between April 2004 and December 2011. We sought risk factors for excessive postoperative exo-drift among patients' demographic and clinical characteristics using univariate and multivariable linear regression analysis. RESULTS: Younger patients (P = 0.007), and those with larger preoperative exo-deviation at distance (P = 0.033), a lower incidence of peripheral fusion at distance (P = 0.021) or a greater postoperative initial eso-deviation (P = 0.001), were significantly more likely to have an excessive postoperative exo-drift (> 20 prism diopters). Univariate analysis revealed significant associations between excessive postoperative exo-drift and age at surgery (P = 0.004), preoperative exo-deviation at distance (P = 0.017) and postoperative initial eso-deviation at distance (P < 0.001). Multivariable linear regression analysis showed that postoperative initial eso-deviation at distance (P = 0.008) was significantly associated with postoperative exo-drift. CONCLUSIONS: Postoperative exodrift in unilateral RR is predicted by the initial postoperative eso-deviation, which may offset the overcorrection. However, the exo-drift is greater in cases with a large preoperative exo-deviation and/or at a younger age, and should be followed carefully.

Formulas to Estimate Appropriate Surgical Amounts of Unilateral Recession-Resection in Intermittent Exotropia with Distance-Near Disparity.

The purpose of this study was to derive new formulas to provide an optimal surgical procedure and optimal amount of recession-resection (RR) surgery in intermittent exotropia (IXT) with a disparity in angle of deviation depending on the fixation distance. The records of 117 consecutive patients with IXT who underwent RR surgery between March 2008 and December 2011 at Okayama University Hospital were retrospectively examined. Multivariable linear regression analysis was performed using the observed corrective angle of deviation at distance or near fixation as the dependent variable, and amounts of lateral rectus muscle (LR) recession (mm) and medial rectus muscle (MR) resection, and age at surgery (years) as independent variables. Two simultaneous formulas were derived: corrective angle of deviation at distance fixation (°)=1.8×recession (mm)+1.6× resection (mm)+0.15×age (years)-6.6, and corrective angle at near fixation (°)=1.5×recession (mm)+1.7× resection (mm)+0.18×age (years)-3.8. Comparisons of coefficient values of the formulas between distance and near fixation revealed that LR recession was more affected by the corrective angle in distance than near fixation. MR resection was more affected at near than distance fixation. We found that our new formulas estimated the appropriate amount of unilateral RR surgery.

Differences in the Stability and Amount of Postoperative Exodrift with Age after Unilateral Lateral Rectus Muscle Recession and Medial Rectus Muscle Resection of Intermittent Exotropia.

We investigated variances in the stability and amount of postoperative exodrift among age groups of intermittent exotropia (XPT) patients who underwent unilateral lateral rectus muscle recession and medial rectus muscle resection. We analyzed the cases of 110 consecutive patients who underwent the surgery in 2004-2011, dividing the patients into groups by their age at surgery: <10, 10-19, and ≥20 years. We performed a regression analysis (dependent variable: postoperative exodrift (°); independent variable: number of days post-surgery) using the formula of curve lines. When the tangent line slope was = 0.01 (°/days) for each group, we defined the numbers of days until alignment became stable as the 'stable days.' We evaluated the between-group differences in the amount of exodrift calculated for the stable days. The coefficients and coefficients of determination for the fitting curves were: <10 year group: f(x)=12.2 (1-e-0.0183x) (r2=0.588, p<0.05); 10-19 year group: f(x)=10.0 (1-e-0.0178x) (r2=0.453, p<0.05); ≥20 year group: f(x)=3.40 (1-e-0.0382x) (r2=0.217, p<0.05). There were 389 , 388, and 153 stable days, and the estimated postoperative exodrift with long-term follow-up was 11.5±3.7°, 9.3±4.4°, and 4.1±3.6° for the < 10 year, 10-19 year, and ≥ 20 year groups, respectively (≥20 year vs. other 2 groups, p<0.05). Longer periods and more postoperative exodrift were associated with younger age at surgery. The postoperative evaluation was approx. ≥ 1 year post-surgery in patients aged < 20. These findings may contribute to evaluating XPT's success rate and prognoses.

Quantitative Analysis of the Effects of a Bangerter Filter on Gross Stereopsis in Experimental Models of Reduced Visual Acuity.

Although a 0.3 Bangerter filter, which reduces visual acuity, is frequently used for treating moderate amblyopia, the effects on gross stereopsis are not well known. This study quantitatively evaluated whether gross stereopsis is degraded by a Bangerter filter. Seven healthy subjects (median age: 29 years) participated in this psychophysical study. Targets with crossed disparities of 1°, 2°, 3°, 4°, and 5° were randomly presented on a three-dimensional television display. The subjects indicated the point at which the targets popped out from the television screen (matching method). The distance from the screen to the point was defined as the degree of stereopsis. This experiment was performed with and without a 0.3 Bangerter filter. The corrected monocular visual acuities were decreased to about 20/63 by the filter in all subjects. No significant difference was observed for any of the disparities (1°-5°), between the degree of stereopsis visualized with and without filters for either the dominant or the non-dominant eye. The degree of stereopsis was not degraded by the reduced visual acuity induced by the use of 0.3 Bangerter filters. In this regard, the use of 0.3 Bangerter filters may be considered safer than occlusion eye patches for the patients with normal binocular vision.

Combining Fresnel and block prisms to measure large angles of strabismic deviation.

PURPOSE: A method was developed to measure strabismic angles >50Δ by stacking commercially available Fresnel and block prisms in the same direction ("piggyback prisms"). METHODS: With a laser pointer (wavelength of 532 nm) as the light source, the deviation of the laser spot produced by the stacked prisms was measured on a tangent screen placed 100 cm away from the prisms. To the obtained data with combinations of Fresnel prisms (5Δ-40Δ) and block prisms (10Δ-50Δ), a cubic surface function was fitted by polynomial regression. RESULTS: The combined effect of stacked prisms was always greater than the arithmetic sum of the labeled values of two prisms (by up to 66Δ), increasing exponentially with each prism power and reaching the maximum of 156Δ for the Fresnel/block combination of 30Δ/50Δ. We obtained contour plots to evaluate the optically induced additivity error and constructed look-up tables for quickly determining the combined effect of the prisms based on their labeled values. CONCLUSIONS: Stacking prisms is a practical method to evaluate a large strabismic angle that cannot be measured by any single prism and is especially useful in dealing with severely paralytic strabismus.

Peripheral refraction in Japanese schoolchildren with low to moderate myopia.

PURPOSE: To report the profile of peripheral refraction in Japanese children with mild to moderate myopia and compare it with reported data from other countries. STUDY DESIGN: Cross-sectional study. METHODS: Subjects were 76 Japanese children with myopia (mean± SD [range] spherical equivalent, -3.04±0.98 [-0.50 to -4.50] D; mean age, 10.0±1.5 [6-12] years). We performed cycloplegic refraction using an open-field autorefractor FR-5000 (Grand Seiko) while the subject looked at external fixation targets located at 0, ±15, ±30 degrees from the center along the horizontal meridian. Only the right eye data were analyzed after converting the readings to the power vector of M (spherical equivalent), J180, and J45. RESULTS: The profile showed a clear hyperopic shift of M from the fovea to the peripheral retina, although a wide inter-subject variation existed. At the gaze positions of ±30 degrees, the mean relative M were +1.16±0.89 D and +1.64±1.02 D (nasal and temporal retina, respectively). Those for J180 were -0.94±0.30 D and -0.70±0.30 D (nasal and temporal retina, respectively). The mean J45 remained small (≦ 0.17 D) within this range of eccentricity. There was no correlation between the relative M at the gaze position of -30 degrees and on-axis refraction, axial length, or children's age (p > 0.05). CONCLUSIONS: The profile of peripheral refraction was similar to that reported in children with moderate to high myopia in other East Asian countries. In this cohort, we did not find evidence supporting a hypothesis that greater myopia and longer axial length are associated with a greater peripheral hyperopic shift of the refraction.

The optimal cut-off value of non-cycloplegic autorefraction for diagnosing myopia in school-aged children.

PURPOSE: To determine the optimal cut-off value of non-cycloplegic autorefraction for diagnosing myopia and estimating myopia prevalence in school-aged children. STUDY DESIGN: Retrospective case-control study. SUBJECTS AND METHODS: Based on age and sex, case-control data were extracted from the medical records of children who underwent autorefraction before and after instillation of 1% cyclopentolate eye drops. We regarded a spherical equivalent (SEQ) of -0.50 D or less found by cycloplegic autorefraction as myopia and determined the optimal cut-off value of non-cycloplegic autorefraction for diagnosing myopia using a receiver operating characteristic (ROC) curve and diagnostic performance (DP) plots. RESULTS: Of a total of 232 children (mean age 8.2 [range: 6-12] years, 126 boys [54.3%]), 116 (50.0%) had myopia. In this cohort, the optimal cut-off SEQ for diagnosing myopia was -0.75 D with a sensitivity of 90.5% and specificity of 95.7%. However, the DP-plots indicated that the cut-off value significantly varied with prevalence of myopia: -1.31 D, -0.81 D, and -0.65 D for the prevalence of 30%, 50%, and 80%, respectively. For non-cycloplegic autorefraction, we found greater accommodation in children aged 6 years and hyperopic eyes (p < 0.001). CONCLUSION:  When diagnosing myopia using non-cycloplegic autorefraction alone with a theoretical cut-off SEQ of -0.50 D, the prevalence of myopia will be overestimated, and we need to set the cut-off value lower (more myopic) especially in younger children with low prevalence.

Double-under muscle transposition: an effective surgical option for large-angle paralytic strabismus.

PURPOSE: To describe our surgical outcomes using a novel muscle transposition procedure, or double-under muscle transposition (DUT), in the treatment of paralytic strabismus. METHODS: In this surgery, the split halves of the superior and inferior rectus muscles opposite the paralyzed muscle are disinserted, crossed under both the remaining half and the paralyzed muscle, and anchored at opposite corners of the insertion of the paralyzed muscle. The medical records of consecutive patients who underwent DUT were retrospectively reviewed. Outcome measures were angle of deviation and duction deficit. RESULTS: Seven patients were included. Diagnoses included WEBINO (n = 1), rupture of the medial rectus muscle (n = 1), and abducens nerve palsy (n = 5). DUT alone was performed in 3 patients; DUT combined with antagonist muscle recession, in 4 patients. One patient underwent the surgery bilaterally. Mean follow-up was 17 ± 18+ months (range, 7-57). Preoperative angles of distance deviation ranged from 25Δ to 142Δ in magnitude. All except a single patient had duction limitation of grade -5. The mean change in distance deviation for DUT alone for each operated eye was 60Δ ± 6Δ (53Δ-65Δ); for combined surgery, 69Δ ± 23Δ (range, 52Δ-103Δ). Final mean angle of deviation at distance was +2Δ ± 3Δ (-4Δ to 0Δ), although an additional surgery was required for large overcorrections in 2 patients. Duction limitation improved in all patients. One patient experienced a postoperative vertical deviation. CONCLUSIONS: DUT may be an alternative for patients with severely paralytic strabismus not likely to resolve with previously reported muscle transposition surgeries. Overcorrection may occur in some cases.

Contribution of vergence adaptation to difference in vertical deviation between distance and near viewing in patients with superior oblique palsy.

PURPOSE: To evaluate the adaptive vertical vergence aftereffect and determine whether it contributes to a difference of vertical deviation with respect to gaze distance in patients with vertical strabismus. DESIGN: Prospective noncomparative studies. METHODS: Eighty-four patients with unilateral superior oblique palsies were enrolled and classified into three types-A, B, and C-based on the difference in vertical deviation between distant and near viewing. The prism adaptation test was performed for 2 to 3 hours to correct vertical deviation and the response of vertical deviation to the prism adaptation test was compared among the three types RESULTS: Adaptive vertical vergence aftereffect, defined as an increase of deviation by 5 prism diopters or more with the prism adaptation test, was identified in 13 patients (16%) at distance and in 23 patients (27%) at near viewing. Among the three types, the adaptive vergence aftereffect contributed mostly to the type B, in which distance deviation exceeds near deviation. Nine patients (39%) of type B changed to type A category with the prism adaptation test; and of these, 7 increased near deviation so that the deviation difference between distant and near viewing decreased. CONCLUSION: The adaptive vertical vergence aftereffect contributes to a difference in vertical deviation between distant and near viewing. The vertical prism adaptation test is specifically useful to determine the extent of surgery by breaking fusional vergence in patients with hypertropia in whom deviation differs with respect to viewing distance.

Transposition of the anterior superior oblique insertion as a treatment for excyclotorsion induced from limited macular translocation.

PURPOSE: To evaluate the transposition of the anterior superior oblique insertion as a treatment for cyclovertical diplopia accompanied by an awareness of tilted image perceived with the affected eye induced from limited macular translocation (LMT). DESIGN: Observational case series. METHODS: Transposition of the anterior part of the superior oblique tendon combined with or without vertical muscle surgery on the affected eye was retrospectively studied in seven patients. Clinical outcome was assessed for binocular and monocular vision. A successful result was defined as restoration of single binocular vision (SBV) at distance and near examined with the Bagolini test with disappearance of a tilted image perceived in the affected eye. RESULTS: Six of seven patients (86%) became unaware of tilted image, and three patients (43%) obtained successful results after the strabismus surgery. Of these three patients with successful results, one (33%) patient recognized metamorphopsia, whereas two (67%) of the three patients with unfavorable results reported metamorphopsia. Patients with successful results showed a visual acuity of 20/25 or better in the affected eye and a significantly smaller difference in visual acuity between the two eyes than those patients with unfavorable surgical results (0.133 logarithm of the minimal angle of resolution for SBV(+) vs 0.675 logarithm of the minimal angle of resolution for SBV(-); P =.0255). CONCLUSIONS: The relatively low success for restoration of SBV indicates that strabismus surgery is recommended for patients whose difference in visual acuity between the two eyes is small and who have a high level visual acuity of the affected eye.

Passive length-tensile properties of extraocular muscles under botulinum toxin type C.

PURPOSE: Passive length-tension of the extraocular muscle was measured after injection of botulinum neurotoxin type C (BoNT-C) to evaluate its chemo-denervation effect. METHODS: BoNT-C was injected unilaterally at 5.0 or 2.5 units in the superior rectus muscle of the albino rabbit. The muscle was separated several times at its original insertion between 3 days to 8 weeks after injection, and the passive length-tension produced by stretching the muscle from its physiologic length was measured. The length-tension curve was analyzed, and the passive load was determined from early components. The compliance was determined by approximating the entire ascending curve by an exponential function. RESULTS: In the 5.0-unit group, the passive load increased significantly 2 weeks after injection but decreased to the level of the control group after 4 weeks and remained at that level until after 8 weeks after injection. In the 2.5-unit group, also, there were changes similar to those in the 5.0-unit group, but the changes were not significant compared to the control group. No significant change was observed in the compliance in either group. CONCLUSIONS: Persistent chemo-denervation effect was not observed in passive length-tension at the doses of BoNT-C used in this study. The increase in the passive load soon after injection was suggested to have been caused by the same mechanism as BoNT-A.

Relationship between static ocular counterroll and Bielschowsky head tilt phenomenon.

PURPOSE: This study was conducted to assess how hyperdeviation of a paretic eye during ipsilesional head tilt-the Bielschowsky head tilt phenomenon (BHP)-can be explained by decreased compensatory ocular counterrolling (OCR) due to the depressed torque of the paretic superior oblique (SO) muscle. METHODS: Thirty-three patients with clinically diagnosed SO palsy and 11 control subjects were studied. With a head-mounted video camera, static ocular counterrolling (s-OCR) was determined by measuring the inclination of a line connecting the two centroids of the characteristic iris pattern and corneal reflex. The BHP was measured with the alternate prism and cover test. RESULTS: The mean (SD) amplitude of s-OCR in paretic eyes based on the fit of the regression sine curve against the ipsilesional head tilt angle was significantly decreased compared with that for contralesional head tilt, 6.3 (3.5) degrees for ipsilesional and 11.3 (3.9) degrees for contralesional (P < 0.001), and was significantly smaller than that in normal subjects: 10.9 (2.6) degrees (P < 0.001). No significant linear relation was noted between hyperdeviation on ipsilesional head tilt and the amplitude of s-OCR in paretic eyes (r(2) = 0.04; P = 0.29). However, the differences between the hyperdeviation with ipsilesional 30 degrees head tilt and with head-upright position correlated significantly with the amplitudes of s-OCR in paretic eyes (r(2) = 0.19, P = 0.01). CONCLUSIONS: The absolute value of the hypertropia on ipsilesional head tilt in clinically diagnosed SO palsy does not directly assess the function of the SO muscle. The difference in hypertropia between ipsilesional head tilt and the upright position, however, may be a better indicator of SO function.

Case report and literature review of inferior rectus muscle aplasia in 16 Japanese patients.

PURPOSE: To describe clinical features of inferior rectus muscle aplasia in Japanese patients and to gain insight into its pathogenesis. METHODS: Case presentation and literature review of 16 Japanese patients with inferior rectus muscle aplasia. RESULTS: The age at presentation of 16 patients (9 females, 4 males, and 3 with unknown gender) varied from 7 months to 73 years (mean, 21.8 years). The inferior rectus muscle was absent on the right side in 10 patients, on the left side in 4 patients, and on both sides in 2 patients. Structural anomalies of the eye globe, such as microphthalmos, microcornea, and coloboma of varying degrees, were present on the ipsilateral side of the inferior rectus muscle aplasia in 4 patients and on the contralateral side in 1 patient. As surgical findings, anomalous inferiorly located insertion of the medial rectus muscle was discovered in 5 patients: 1 patient in association with microcornea and iris coloboma. Frequent surgical procedures were recession or tenotomy of the superior rectus muscle, combined with downward transposition of the entire or partial tendons of the medial rectus and lateral rectus muscle to the medial and lateral end, respectively, of the putative inferior rectus muscle insertion. CONCLUSIONS: The association of coloboma with inferior rectus muscle aplasia suggests that abnormal optic fissure closure during embryogenesis might underlie the muscle aplasia.

Chromosomes 4q28.3 and 7q31.2 as new susceptibility loci for comitant strabismus.

PURPOSE: This study was designed to localize chromosomal susceptibility loci for comitant strabismus among Japanese families by genome-wide linkage analyses. METHODS: Fifty-five Japanese families, with at least two members with comitant strabismus (esotropia and/or exotropia), were subject to full ophthalmic examination, careful ocular history, and review of medical records. DNA was obtained and genotyping was performed with PCR amplification of 400 microsatellite markers. Parametric and nonparametric linkage (NPL) analyses scores were calculated. Linkage analysis was performed for the whole set of families (55 families), and then a second analysis was performed for two subgroups with the phenotypes, esotropia and exotropia. RESULTS: A multipoint parametric heterogeneity logarithm of the odds (HLOD) score of 3.62 was obtained at marker D4S1575 under a dominant model, with a NPL score of 2.68 (P=0.001). Testing under different penetrances and disease allele frequencies revealed two other susceptibility loci at 7q31.2 under a recessive model (HLOD scores=3.93 and 4.40 at 125.2 cM and 107.28 cM, respectively). Analysis of the subgroups revealed new susceptibility loci for esotropia; one locus at 8q24.21 is worthy of further investigation. CONCLUSIONS: This study suggests multiple susceptibility loci for comitant strabismus. The loci at chromosomes 4q28.3 and 7q31.2 show a significant evidence of linkage.