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To determine the optimal cut-off value of non-cycloplegic autorefraction for diagnosing myopia and estimating myopia prevalence in school-aged children.Retrospective case-control study.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.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 (p0.001). 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.

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.

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

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.

The data for 94 consecutive patients with intermittent exotropia of basic type, ranging from 20 to 40 prism diopters (delta), who preoperatively wore neutralizing prisms for 3 to 5 days, were studied retrospectively. The surgery in 43 patients in whom the amount of increase of angle was 4delta or less was based on the original angle (Group A), while that in 51 patients in whom the magnitude of increase was 5delta or more was based on the increased angle of deviation (Group B). Patients with initial deviation less than 30delta and patients younger than 7 years of age showed an increase of deviation with prism correction. There were no significant differences in surgical results between the two groups at 1 year, and at 3 years; although at 3 years satisfactory motor alignment and binocular function for single vision at distance was higher in Group B than that in Group A.

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.

We evaluated the characteristics of phoria adaptation for vertically induced retinal disparity. An adaptive change in the fusion-free ocular alignment, phoria adaptation, was measured with a computer-aided mirror haploscope at 10, 30, and 60 minutes after the start of wearing of a 3-prism-diopter base up prism by 35 normal subjects ranging in age from 21 to 67 years (mean: 37 years). The relationships between phoria adaptation and the subjects' age, the vertical fusional amplitude, the amount of heterophoria, and the starting time of the examination were evaluated. All subjects showed phoria adaptation, with the mean (+/- SD) degree of 0.78 +/- 0.28 degree, 0.96 +/- 0.26 degree and 1.02 +/- 0.30 degrees at 10, 30, and 60 minutes, respectively, after wearing the prism. The repeatability (95% confidence interval) for the measurements was less than +/- 0.24 degree. There was a significant correlation between the vertical fusional amplitude and the gain of phoria adaptation (at 10 and 60 minutes, P0.05). The gain of phoria adaptation measured at 60 minutes showed a significant decrease with age (P0.01). The results indicate that the time course of phoria adaptation in the vertical direction is similar to that in the horizontal direction and its gain differs considerably among subjects.

We quantitated the morphological changes in the orbital surface layer muscles in the rabbit following the single injection of botulinum A toxin. Experiments were performed in 9 white rabbits (1.6–3.0 kg). They were administered 5 units (5 rabbits) or 10 units (4 rabbits) of botulinum toxin injected into the superior rectus muscle of one eye. The diameter of myofibers of the orbital and intermediate layer zones was measured with an ocular micrometer on histological sections 3 days and 1, 3 and 5 weeks after injection. Quantitative changes were noted in the muscle fibers of the orbital surface layer zone following the injection of 10 units of botulinum toxin. At 1 week, the diameter of myofibers in the orbital layer was reduced, but it was increased at 5 weeks compared to that in the control eyes; in contrast, no change in the diameter of muscle fibers was found in the intermediate layer zone.

• Background: The microvascular changes secondary to anterior segment ischemia following tenotomy of the extraocular muscles have not been studied in the rabbit. • Methods: Using scanning electron microscopy of methylmethacrylate ocular microvascular luminal castings, the anterior eye segment vasculature after tenotomy was documented and compared to that after occlusion of the bilateral long posterior ciliary arteries and that in the eyes that were not subjected to any surgical intervention. • Results: Five days and 1 week after the surgical intervention with tenotomy, microvascular change secondary to the anterior segment ischemia was not apparent, but 2 weeks after the tenotomy subtle evidence of ischemia such as new vessels in the iris was observed. Seven weeks after tenotomy, marked microvascular change was observed where corneal new vessels arose from the superior perilimbal arteries. In contrast, we found prominent microvascular changes 2 weeks after the occlusion of the long posterior ciliary arteries. • Conclusions: Tenotomy of the rabbit eye causes microvascular change similar to that in occlusion of the long posterior ciliary arteries. This result suggests that the anterior ciliary artery of the rabbit contributes blood flow to the anterior eye segment and also has a stronger connection with the long posterior ciliary artery than previously reported.

Although scleral search coils are widely and accurately used for the measurement of Listing’s plane in both eyes, they require specialized equipment and are invasive. In this study, we describe a convenient and less invasive method that uses a synoptometer to analyze the differences in orientation of Listing’s plane (difLP), and the effects of vertical muscle surgery on the difLP tilt in patients with superior oblique palsy (SOP). Seventeen patients with unilateral congenital SOP (CSOP) and four patients with unilateral acquired SOP (ASOP) who had not undergone any strabismus surgeries were examined. Cyclodeviations of 13 vertical and horizontal gaze points within 30° were measured with a synoptometer, and the difLP tilts in the yaw and pitch planes were analyzed before and after vertical muscle surgery. The difLP tilt in the CSOP patients was significantly tilted nasally (p = 0.02) and forward on the lower side (p = 0.001), whereas that in ASOP patients tended to tilt temporally (p = 0.15). Ipsilateral inferior oblique recession (IOR) performed in seven CSOP patients tended to improve the difLP tilt in both the yaw (p = 0.07) and pitch (p = 0.09) planes, whereas contralateral inferior rectus recession (IRR) performed in three CSOP patients significantly improved the difLP tilt in the pitch plane (p = 0.015). The mean excyclodeviations in the 13 gaze points were significantly improved with both procedures (p

We conducted a retrospective study of 25 patients with acute-onset comitant esotropia to evaluate whether the timing of the start of treatment is a critical factor in the development of normal stereopsis. The mean age at onset was 12 years 4 months, and mean age at the start of treatment was 17 years 9 months. Bifixation was defined as a stereoacuity threshold score that was numerically lower than 60 seconds of arc on stereotesting. An operation was performed on the nonfixating eye for the prism-adapted angle. At the final examination, bifixation was observed in four patients (16%) with the Randot test and in 15 patients (60%) with the Titmus test. No relationship was found between the time of the start of treatment and the postoperative development of stereopsis, nor was there a significant (P > .10) difference between the two groups with early and delayed start of treatment in the proportion of patients with bifixation.

Background: The modified Harada-Ito procedure has been reported to be an effective treatment for correction of cyclotorsion in bilateral superior oblique palsy. However, there are no reports regarding its use in intraoperative adjustable suture surgery. Methods: The authors performed a retrospective study of 12 patients with traumatic bilateral superior oblique palsy who were classified as having either symmetric or asymmetric palsy according to the symmetry of the alternate hyperdeviation on side gazes. Cyclotorsion and vertical and horizontal deviation in the nine diagnostic positions were measured preoperatively and postoperatively. Results: Of the 12 patients, 6 were determined to have symmetric palsy and 6 asymmetric palsy. Intraoperative adjustable suture surgery with the modified HaradaIto procedure was performed bilaterally in the six patients with symmetric palsy and unilaterally in those with asymmetric palsy. The median measured value of extorsion in the primary position was reduced from 14.5° to 2.5° in patients with symmetric palsy and from 9.5° to 2.0° in those with asymmetric palsy. In downgaze, some degree of residual extorsion remained, and there was no significant change in esodeviation after surgery. In five patients with symmetric palsy and in all of those with asymmetric palsy, normal single binocular vision in the primary position but did not that in downgaze was restored after surgery. Conclusion: Intraoperative adjustable suture surgery is an effective treatment in correcting torsion, but may not be as effective for esodeviation in downgaze. Ophthalmology 1994;101:188-193

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.

To describe clinical features of inferior rectus muscle aplasia in Japanese patients and to gain insight into its pathogenesis.Case presentation and literature review of 16 Japanese patients with inferior rectus muscle aplasia.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.The association of coloboma with inferior rectus muscle aplasia suggests that abnormal optic fissure closure during embryogenesis might underlie the muscle aplasia.

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.

We evaluated the efficacy of eye muscle surgery in 4 patients with ocular myasthenia gravis with troublesome diplopia. All patients were in remission and had shown a consistently stable angle of deviation for at least 6 months preoperatively. The extent of eye muscle surgery was based on the degree of deviation in the primary position, and conventional recession and resection procedures were performed in 3 patients and hang-loose recession with an adjustable recession in 1. Single binocular vision was obtained in 3 patients in the primary position without prism correction or compensatory head posture. Electron-microscopic studies on the eye muscle specimens obtained at strabismus surgery revealed non-specific degenerative findings for the muscle fibers and sarcomeric disorganization compared to that in a control extraocular muscle.

To determine the precise site of reattachment of recessed muscles, 4-mm conventional and hang-back recessions of the inferior rectus muscle were performed in 18 albino rabbits. Six weeks later, the distance from the anterior border of the reattached muscle to the insertion was measured both grossly and microscopically. In all cases the operated muscles had advanced minimally from the site of surgical placement. Gross observation showed that the mean forward creep was significantly greater for those rabbits which underwent hang-back recession (1.81 +/- 0.67 mm) than for those that were submitted to the conventional technique (0.83 +/- 0.38 mm). Measurements done on histological sections revealed that the mean distance of the anterior border of the muscle fiber from the reference suture was larger for conventional recession (2.73 +/- 0.75 mm) than for hang-back recession (1.91 +/- 0.72 mm).

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.