Immunologic assessment and KMT2D mutation detection in Kabuki syndrome.

Kabuki or Niikawa-Kuroki syndrome (KS) is a rare disorder with multiple malformations and recurrent infections, especially otitis media. This study aimed to investigate the genetic defects in Kabuki syndrome and determine if immune status is related to recurrent otitis media. Fourteen patients from 12 unrelated families were enrolled in the 9-year study period (2005-2013). All had Kabuki faces, cleft palate, developmental delay, mental retardation, and the short fifth finger. Recurrent otitis media (12/14) and hearing impairment (8/14) were also more common features. Immunologic analysis revealed lower memory CD19+ cells (11/13), lower memory CD4+ cells (8/13), undetectable anti-HBs antibodies (7/13), and antibody deficiency (7/13), including lower IgA (4), IgG (2), and IgG2 (1). Naïve emigrant lymphocytes, lymphocyte proliferation function, complement activity, and superoxide production in polymorphonuclear cells were all normal. All the patients had KMT2D mutations and 10 novel mutations of R1252X, R1757X,Y1998C, P2550R fs2604X, Q4013X, G5379X, E5425K, R5432X, R5432W, and R5500W. Resembling the phenotype of common variable immunodeficiency, KS patients with antibody deficiency, decreased memory cells, and poor vaccine response increased susceptibility to recurrent otitis media. Large-scale prospective studies are warranted to determine if regular immunoglobulin supplementation decreases the frequency of otitis media and severity of hearing impairment.

Impaired neural drive in patients with low back pain.

BACKGROUND: Control of trunk movement relies on the integration between central neuronal circuits and peripheral skeletomuscular activities and it can be altered by pain. There is increasing evidence that there are deficits within the central nervous system controlling the trunk muscles in people with low back pain (LBP). However, it is unclear how LBP impacts upon neural drive to back muscles at different levels of voluntary contraction. Therefore, the purpose of this study was to investigate if neural drive is impaired in these patients. METHODS: Seventeen patients with LBP and 11 healthy controls were recruited. Bilateral electromyographic (EMG) recordings were obtained from the erector spinae (ES) muscles at two vertebral levels (T12 and L4). Participants performed a series of brief isometric back extensions (50-100% maximum voluntary contraction - MVC), during which transcranial magnetic stimulation was delivered. The size of the evoked (superimposed) twitch was measured using dynamometry. RESULTS: The size of the superimposed twitch decreased linearly with increasing contraction strength in the controls; however, this linear relationship was not observed in the patients. Additionally, patients had larger superimposed twitches and longer time-to-peak amplitudes during MVCs than those observed in controls. Furthermore, patients had lower MVC and root-mean-square EMG activity of ES muscles during MVCs. CONCLUSIONS: A decline of central neural drive to the back muscles at high level of voluntary contraction was observed in patients with LBP. These results suggest that it might be pertinent to include neuromuscular facilitation programmes and therapeutic exercise utilizing high voluntary contractions for patients with LBP.

Astigmatism and biometric optic components of diode laser-treated threshold retinopathy of prematurity at 9 years of age.

PURPOSE: To assess the prevalence of astigmatism and its relationship with biometric optic components in preterm school children with diode laser-treated threshold retinopathy of prematurity (ROP). METHODS: A prospective, cross-sectional study in which cycloplegic keratometry, refraction, and ultrasound biometric measurement of optic components were performed on 24 consecutive preterm children with diode laser-treated threshold ROP at the age of 9 years. The study results were compared with data on 1021 age-matched full-term control children from a national survey. RESULTS: The laser-treated eyes had a mean astigmatism of 3.47 D, with a mean spherical equivalent of -4.49 D. Of the 46 eyes studied, 98% of eyes showed astigmatism ≥0.5 D and 50% had high astigmatism (>3.0 D). Most astigmatic eyes (97.7%) showed with-the-rule astigmatism, with the mean plus cylinder axis at 89.30(o). Further correlation analysis showed the astigmatism in refraction was highly correlated with the corneal astigmatism (r=0.921, P<0.001) and the vertical corneal curvature (r=0.405, P=0.005). There was significantly steeper vertical corneal curvature (P=0.003) and flatter horizontal corneal curvature (P=0.031) in eyes with laser-treated ROP when compared with age-matched full-term controls. The eyes with laser-treated ROP also show significantly thicker lens (3.93 mm) and shallower anterior chamber depth (ACD; 2.92 mm) than full-term controls (P<0.001). CONCLUSIONS: There is significantly higher prevalence and greater magnitude of astigmatism in eyes with laser-treated threshold ROP compared with full-term controls. The steeper vertical corneal curvature component contributes to the increased astigmatism in eyes with laser-treated ROP.

Peripapillary intrachoroidal cavitation in high myopia: reappraisal.

PURPOSE: To evaluate optical coherence tomography (OCT) and clinical findings of a peripapillary lesion in high myopia recently named peripapillary detachment in pathologic myopia (PDPM) or intrachoroidal cavitation. METHODS: Observational case report by chart review, analysis of colour fundus photography, fluorescein angiography, and OCT in 16 eyes of 12 patients with myopic degeneration and the presence of a slightly elevated, patchy peripapillary, yellow-orange lesion on the fundus. RESULTS: Patients were mean age 53.1+/-10.7 years, with a spherical-equivalent refractive error of -10.99+/-3.33 D and mean axial length of 27.34+/-1.44 mm. The mean best-corrected visual acuity was log MAR 0.3+/-0.2 (between 20/100 and 20/20). Six eyes also showed myopic maculopathy. In 13 eyes, OCT showed an intrachoroidal hyporeflective space located below the normal plane of the retinal pigment epithelium. Six of these 13 eyes were found to have apparent communication between the intrachoroidal cavity and the vitreous space at the junction of the lesion and the myopic conus. In three eyes, OCT revealed intrachoroidal splitting. The fluorescein angiogram showed early hypofluorescence, without pooling or staining in late phase. CONCLUSIONS: The yellow-orange elevated patchy lesions adjacent to the peripapillary conus in high myopic eyes may represent either intrachoroidal cavitation or choroidal schisis, which may be different stages of one disease spectrum. Vitreous fluid may be the source of the disruption of choroid and fluid accumulation.

Changes of the ocular refraction among freshmen in National Taiwan University between 1988 and 2005.

PURPOSE: The prevalence of myopia in Taiwan has been reported to be increasing in the sequential nationwide survey. The purpose of this study is to compare the change of ocular refraction among freshmen in 1988 and 2005 in National Taiwan University. METHODS: The refractive status of freshmen in National Taiwan University in 2005 was examined. The refractive status and corneal radius of each student were measured with autorefractometer. The data was compared with the data obtained in 1988. All the refractions of the right eye were chosen and myopia was defined as a mean spherical equivalent of -0.25 D or more. RESULTS: The mean refractive status of total 4686 freshmen was -4.25+/-2.74 D in 1988 (-4.12+/-2.72 D for males and -4.41+/-2.75 D for females). The prevalence of myopia was 91.3% (90.1% for males and 92.8% for females). The prevalence of high myopia (over -6.0 D) was 23.5% (22.2% for males and 25.1% for females). In 2005, the mean refractive status of total 3709 freshmen was -4.93+/-2.82 D (-4.93+/-2.83 D for males and -4.93+/-2.80 D for females). The prevalence of myopia was 95.9% (95.9% for males and 95.9% for females). The prevalence of high myopia was 38.4% (38.1% for males and 38.8% for females). CONCLUSIONS: The prevalence and severity of myopia in freshmen of National Taiwan University increased significantly in 2005 compared to 1988. The distribution of refractive status in different college changed also. These findings may be explained by the early onset of myopia.

Characteristics of primary rhegmatogenous retinal detachment in Taiwan.

PURPOSE: To investigate the epidemiological characteristics and related risk factors for primary rhegmatogenous retinal detachment (RRD) in Taiwan. METHODS: The case-control study was based on retrospective chart review of hospital patients treated for primary RRD from 1995 to 2001, inclusively. The preoperative fundus findings and refractive status were collected for each patient. Controls were selected from a nationwide survey of visual impairment in the adult population during the same period. Risk factors for RRD were analysed by logistic regression. A total of 1032 RRD cases and 3537 controls were enrolled for the study. RESULTS: A pronounced bipeak pattern was evident in the age distribution for primary RRD in the third and sixth decades of life. Atrophic hole with lattice degeneration was preferential to younger (20-30 years) and highly myopic individuals (-7.4+/-5 D), whereas the flap tear tended to occur in middle-aged individuals (50-60 years) and those with moderate myopia (-4.1+/-5 D). The odds ratio for primary RRD with myopia, male gender, and older age (>40 years) were 1.33/D, 2.15, and 1.69, respectively. CONCLUSIONS: Myopia is an important RRD risk factor for young Taiwanese. The increasing prevalence of myopia has predisposed the young population to RRD.

Visual outcomes for high myopic patients with or without myopic maculopathy: a 10 year follow up study.

AIM: To evaluate the visual outcomes for high myopic patients aged 40 years and older with or without myopic maculopathy. METHODS: 552 high myopic (spherical equivalent < or =-6.0D or axial length > or =26.5 mm) patients were enrolled in the study, 230 cases with myopic maculopathy (at least lacquer cracks were identified) and 322 cases without maculopathy. The initial and final visual acuity (VA) (after 10 years) was compared between two groups. Additionally, the relation between sex, age, refraction, and axial length was analysed to find out the possible risk factors associated with visual outcome in myopic maculopathy. RESULTS: In 92% of patients aged 40-49, final VA was better than 20/40 after 10 years of follow up. However, it was less than 40% in those older than 60 years. For more than 50% of patients older than 40 years of age with maculopathy, their vision had decreased more than two lines in Snellen VA after 10 years of follow up, compared to only 4.3% of analogues without myopic maculopathy. Patchy atrophy and choroidal neovascularisation in myopic macular degeneration groups showed poorer visual outcome than lacquer cracks in the macular lesion group. Other prognostic factors of visual outcomes were myopic refraction, axial length, and ageing. CONCLUSIONS: Clearly, prognosis for patients with maculopathy is poorer than for those without maculopathy. Refractive status, axial length, and ageing are the main factors involved in determining the visual outcomes. The macular grading also affects the visual outcome for high myopic patients.

Long-term visual prognosis of infantile-onset high myopia.

PURPOSE: To investigate the clinical course and changes of refractive status in infantile-onset myopic children who received fully corrected glasses and to determine their visual prognosis. METHODS: In all, 57 children with infantile-onset high myopia (spherical equivalent over -5.0 D prior to the age of 5 years) were included in this study. All children received initial full-correction glasses at the mean age of 3.52 years. The cycloplegic refraction, axial length, and the best-corrected visual acuity were collected every 6 months. The mean follow-up time was 9.36 years. RESULTS: We noted that the tendency toward progression or regression of myopia appeared to be related to the degree of refractive error. Lower grades of high myopia (-5.0 to -7.75 D) showed a greater tendency to progress than those of the highest initial myopic refraction level (< or = -11.0 D). While the latter group exhibited a more-substantial regression rate than those cases of the lower initial refraction level. About 80% of infantile-onset high myopes demonstrated a final best-corrected vision of greater than 20/40, with 37% of children revealing a best-corrected vision level even better than 20/25. CONCLUSION: Clinical course of infantile high myopia is different to school myopia. Usually, higher degree of high myopia showed a stable state of myopia, or even possible regression, whereas the lower grades of high myopia revealed a strong tendency to progress.

Prevalence of myopia in Taiwanese schoolchildren: 1983 to 2000.

INTRODUCTION: To determine time trends in myopia over a 20-year period in Taiwan, we conducted 5 nationwide surveys pertaining to the ocular refraction of schoolchildren in 1983, 1986, 1990, 1995 and 2000. MATERIALS AND METHODS: The sampling technique used herein involved the assessment of stratified systematic clusters, with the unweighted myopic rate being represented using data derived from different sectors of the population, such as metropolitan, city, town, and aboriginal. The mean values for the spherical equivalent of the cycloplegic refractive status and the dimension of corneal radii as determined by the autorefractometer were used for the calculation. RESULTS: In our review of 5 nationwide myopia surveys, we found that the mean prevalence of myopia among 7 year olds increased from 5.8% in 1983 to 21% in 2000. At the age of 12, the prevalence of myopia was 36.7% in 1983 increasing to 61% in 2000, corresponding figures for 15-year-olds being 64.2% and 81%, respectively. The prevalence of myopia increased from 74% in 1983 to 84% in 2000 for children aged between 16 and 18 years, and, in addition, the prevalence of high myopia (over -6.0 D) increased from 10.9% in 1983 to 21% of 18-year-old students of Taiwan in 2000. The mean refractive status at the age of 12 deteriorated from -0.48 D in 1983 to -1.45 D in 2000, and from -1.49 D to -2.89 D for children aged 15, whilst for individuals aged 18, it deteriorated from -2.55 D in 1983 to -3.64 D in 2000. The mean ocular refraction began to progress to a myopic condition at the age of 11 in 1983, this becoming an age of 8 years in 2000. There appeared to be significant difference in both the prevalence and the degree of myopia between study participants residing in cities and villages. CONCLUSIONS: We conclude that the cause of the relative increasing severity of myopia among the schoolchildren was due to the onset of myopia at a very young, and progressively-decreasing, age over the study period. Thus, to reduce the prevalence and severity of myopia, we should pay more attention to the eye care of pre-schoolchildren.

Standardisation of the description of patellofemoral motion and comparison between different techniques.

Patellofemoral motion is significant clinically, yet in the literature many different methods and terminologies are used, thus making comparison between studies difficult. We review and explain the different methods used for the description of patellofemoral joint motion, compare these methods by experimentation, and propose a standardised method. We found three main methods for describing patellar motion: motion of the patella about femoral body fixed axes, about patellar body fixed axes, and a combination of these. Description about femoral body fixed axes does not make sense clinically. Description about patellar body fixed axes is straightforward, yet the definition of these axes is prone to error due to the lack of anatomical landmarks. The combination method makes most sense clinically and uses more easily found anatomical landmarks. Patellar flexion varied by up to 26% when describing the motion about different axes. Tilt and shift were highly sensitive to the choices of coordinate systems and the axes of motion. The pattern of rotation was consistent between all methods; however, differences between the methods increased with patellar flexion. We propose the description of patello-femoral motion in terms of shift (along a femoral medial-lateral axis), tilt (about the patellar long axis), rotation (about a floating patellar anterior-posterior axis) and flexion (about the femoral medial-lateral axis).

The cornea in young myopic adults.

AIMS: To further understand the effect of refractive error on the corneal dimensions and function. METHODS: Corneal curvature, corneal thickness, and axial length measurements were performed, as well as specular microscopy and fluorophotometry, on patients with various refractive statuses. 216 subjects, mean age 22.2 (SD 4.2) years, were examined. Patients with previous contact lens wear history, external eye diseases, as well as previous ocular surgeries, were excluded. RESULTS: The corneas were flatter in eyes with longer axial length (r = -0.22, p = 0.003). Eyes with more myopic spherical equivalent had longer axial length (r = -0.90, p <0.001) as well as less corneal endothelial density (r = 0.20, p = 0.037). Corneal endothelial density decreased in eyes with longer axial length (r = 0.24, p = 0.019); however, it correlated neither with corneal thickness (r = -0.06, p = 0.59) nor with corneal curvature (r = -0.07, p = 0.52). The corneas had a mean corneal thickness of 533 (SD 29) microm and were thinner in more myopic eyes (r = 0.16, p = 0.021). The corneas tended to be thinner in eyes with longer axial length. However, the correlation did not reach statistical significance (r = -0.11, p = 0.14). Besides, there was no significant correlation between the corneal thickness and the corneal curvature (r = -0.13, p = 0.093) and the endothelial permeability (r = 0.042, p = 0.69). The corneas with higher endothelial density had larger corneal transfer coefficient (r = 0.26, p = 0.024) and higher permeability to fluorescein molecules (r = 0.28, p = 0.014). Nevertheless, the corneal endothelial permeability did not correlate significantly with either the axial length (r = -0.18, p = 0.11) or the degree of myopia (r = 0.12, p = 0.26). CONCLUSION: Changes in the anterior segments as the eyeball elongates in myopia progression included flatter corneal curvature, decreased corneal thickness, as well as decreased endothelial density. These factors should be considered in refractive surgery.

An intervention trial on efficacy of atropine and multi-focal glasses in controlling myopic progression.

PURPOSE: This randomized clinical trial assessed the treatment effects of atropine and/or multi-focal lenses in decreasing the progression rate of myopia in children. METHODS: Two hundred and twenty-seven schoolchildren with myopia, aged from 6 to 13 years, who were stratified based on gender, age and the initial amount of myopia were randomly assigned to three treatment groups: 0.5% atropine with multi-focal glasses, multi-focal glasses, and single vision spectacles. Each subject was followed for at least eighteen months. These results report on the 188 patients available for the follow-up. RESULTS: The mean progression of myopia in atropine with multi-focal glasses group (0.41 D) was significantly less than the multi-focal (1.19 D) and single vision group (1.40 D) (p < 0.0001). But no significant difference was noted between the last two groups (p = 0.44). The progression of myopia was significantly correlated with the increases of axial length (r = 0.65, p = 0.0001), but not with the changes of corneal power (r=-0.09), anterior chamber depth (r = -0.023), lens thickness (r = -0.08), or intra-ocular pressure (r = -0.008). CONCLUSION: The 0.5% atropine with multi-focal lenses can slow down the progression rate of myopia. However, multi-focal lenses alone showed no difference in effect compared to control.

Epidemiologic study of the prevalence and severity of myopia among schoolchildren in Taiwan in 2000.

BACKGROUND AND PURPOSE: A nationwide survey was performed in 2000 to determine the prevalence and severity of myopia among schoolchildren in Taiwan and to compare these findings with the results of the last survey performed in 1995. METHODS: We first divided the whole island into regions according to developmental grade scores and then sampled with the probability proportional to the size of the population within each stratum. A total of 10,889 students were enrolled, including 5,664 boys and 5,225 girls, with ages ranging from 7 to 18 years. The refractive status and corneal radius of each student were measured with an autorefractometer under cycloplegia and checked with retinoscopy. Axial length was measured using biometric ultrasound. RESULTS: The myopia rate increased from 20% at 7 years, to 61% at 12 years, and 81% at 15 years. A myopic rate of 84% was found for schoolchildren aged 16 years through 18 years. The mean refractive index reached myopic status at the age of 8, and increased to -4.12 D in girls and -3.15 D in boys at the age of 18 years. The prevalence of high myopia (> -6.0 D) at the age of 18 years was 24% in girls and 18% in boys. The increase in axial length corresponded with the progression of myopia. The anterior chamber depth was slightly deeper from 7 years to 13 years and then remained stable. The lens thickness decreased from 7 years to 11 years. After age 15, further thickening of the lens was correlated with both age and severity of myopia. However, the corneal curvature was not related to age or severity of myopia. Girls had a higher prevalence and more severe degree of myopia than boys. Children in urban areas had a higher prevalence and more severe degree of myopia than children in rural areas. CONCLUSION: The prevalence and severity of myopia in schoolchildren in Taiwan in 2000 increased compared to 1995, with the most severe increases occurring in younger age groups. Thus, preventing schoolchildren developing myopia at a young age may slow down the increase in severity of myopia in Taiwan.

Evaluation of optic disc changes in severe myopia.

PURPOSE: To evaluate the changes in the optic nerve head in highly myopic subjects by means of confocal laser scanning opthalmoscope. METHODS: Using laser scanning and a three-dimensional image analysis system, we studied 114 young (21.4 +/- 1.4 years), highly myopic subjects with refractive errors greater than -8.0 D and a control group of 29 subjects (18.9 +/- 1.2 years) with myopia of -3.0 D or less. Measurements included cycloplegic refraction, corneal curvature, biometric axial length, and morphometric values of the optic disc obtained with a laser scanning disc analyzer. RESULTS: The optic disc area in highly myopic eyes was similar to that in mildly myopic eyes. However, regression analysis revealed that the optic disc area increased with axial length in subjects with severe myopia. The cup/disc ratio, the disc depth, the neuroretinal rim area, and the tilting of the disc were not significantly different between the severe and mild myopia groups. CONCLUSIONS: These findings may be useful in further investigations of myopic progression and of the mechanisms responsible for the development of myopic complications.

Epidemiologic study of ocular refraction among schoolchildren in Taiwan in 1995.

PURPOSE: In order to understand and update the prevalence of myopia in Taiwan, a nationwide survey was performed in 1995. METHODS: We stratified the cluster sampling by developmental grading of the city, using a size proportional to the population. Two cities were randomly selected from each city grading. The total number of students enrolled was 11,178, including 5,676 boys and 5,502 girls. The refractive status and corneal radius of each student were measured with an autorefractometer under cycloplegia and checked with retinoscopy. Axial length was measured with biometric ultrasound. RESULTS: The myopic rate was from 12% at the age of 6, it increased to 56% at the age of 12, and then to 76% at the age of 15. A myopic rate of 84% was found for the age range of 16 to 18. The prevalence of high myopia (over -6.0 D) at the age of 18 was 20% in girls and 12% in boys. The mean refractive status became myopic at the age of 9, then increased to -3.92 D in girls and -2.71 D in boys at the age of 18. The increase of axial length is correspondent with the progression of myopia. The anterior chamber depth (ACD) was deeper with age and the severity of myopia, whereas the corneal curvature remained unchanged. The lens thickness became thinner from age 7 to 13, then it became thicker with age and the severity of myopia after age 15. The prevalence and degree of myopia in girls was more severe than in boys. CONCLUSIONS: The prevalence of myopia in Taiwan increased year by year. The increase in severity and prevalence of high myopia may be due to earlier onset.

Influence of ophthalmic nerve fibers on choroidal blood flow and myopic eye growth in chicks.

Ophthalmic sensory nerve fibers containing substance P and calcitonin gene-related peptide' innervate the choroid in mammals and are known to vasodilate choroidal blood vessels. The avian choroid is also innervated by ophthalmic nerve fibers containing substance P and calcitonin gene-related peptide. The present studies were carried out to determine the influence of these sensory fibers on choroidal blood flow in birds and characterize their interaction with manipulations affecting eye growth. In these studies, ChBF was measured using laser Doppler flowmetry in both eyes in the following groups of birds: (1) normal chicks; (2) chicks with right optic nerve transected for 2 weeks; (3) chicks with right optic nerve transected and a goggle over the right eye for 2 weeks; and (4) chicks with right optic and ophthalmic nerves transected and a goggle over the right eye for 2 weeks. The eyes were refracted and various ocular dimensions measured after the blood-flow measurements. It was found that optic nerve transection reduced ChBF to 30% of normal. Placing a goggle (which increases ocular temperature by 4 degrees C) over an optic nerve transected eye nearly doubled choroidal blood flow over that in an optic nerve transected eye without a goggle. Additional transection of the ophthalmic nerve in a goggled optic nerve-transected eye, yielded choroidal blood flow that was indistinguishable from that in a nongoggled optic nerve-transected eye. Optic nerve transection had a slight stunting effect on axial growth of the eye. While myopic axial elongation was observed in goggled eyes with the optic nerve cut, the extent of myopia was less than in normal goggled eyes. Ophthalmic nerve transection further reduced the myopia induced by goggling in an optic nerve cut eye. These results suggest that ophthalmic nerve input to the choroid exerts a vasodilatory influence, which is activated in a goggled eye. This increased choroidal blood flow may be in response to elevated ocular temperatures caused by the goggling and this increase appears to be masked in goggled eyes with an intact optic nerve by the reduction in choroidal blood flow normally accompanying myopic eye growth. Our results thus show that the induction of myopic eye growth (as in our optic nerve cut eyes with a goggle) need not be accompanied by a decrease in choroidal blood flow from the baseline no-goggle condition (in this case, with the optic nerve cut).

Effects of different concentrations of atropine on controlling myopia in myopic children.

Although 1% atropine effectively slows myopia progression, it is associated with adverse effects, including photophobia, blurred near vision, and poor compliance. We investigated whether lower doses of atropine would control myopia progression. One hundred and eighty-six children, from 6 to 13 years of age, were treated each night with different concentrations of atropine eye drops or a control treatment for up to 2 years. The mean myopic progression in each of the groups was 0.04 +/-0.63 diopter per year (D/Y) in the 0.5% atropine group, 0.45+/-0.55 D/Y in the 0.25% atropine group, and 0.47+/-0.91 D/Y in the 0.1% atropine group. All atropine groups showed significantly less myopic progression than the control group (1.06+/-0.61 D/Y) (p<0.01). Our study also showed that 61% of students in the 0.5% atropine group, 49% in the 0.25% atropine group and 42% in the 0.1% atropine group had no myopic progression. However, 4% of children in the 0.5% atropine group, 17% in the 0.25% atropine group, and 33% in the 0.1% atropine group still had fast myopic progression (>-1.0 D/Y). In contrast, only 8% of the control group showed no myopic progression and 44% had fast myopic progression. These results suggest that all three concentrations of atropine had significant effects on controlling myopia; however, treatment with 0.5% atropine was the most effective.

Effects of lid suturing and trans-scleral cryotherapy on ocular growth in a piglet model.

PURPOSE: To study whether lid suturing can induce axial myopia and explore whether trans-scleral cryotherapy can affect ocular growth in piglets or not. METHODS: A total of fourteen 2- to 3-week-old piglets were studied. Three groups were included: lid suture, cryotherapy, and both lid suture/cryotherapy groups. The lid suturing group (N = 6) was given lid suturing to produce visual deprivation. The cryotherapy group (N = 4) received trans-scleral cryotherapy 360 degrees to encircle anterior to the equator. Both treatment groups (N = 4) received both cryotherapy and lid suturing. The cycloplegic refraction, corneal power, biometric axial length, and intraocular pressure (IOP) were measured before the experiments and 4 months later. RESULTS: Mild axial myopia was induced in five lid-sutured eyes of the lid suturing group. The ocular refraction and eye size of cryotherapy eyes were not different from the control eyes in the cryotherapy group. More myopia was found in all four piglets that received both cryotherapy and lid suturing. CONCLUSIONS: Lid suturing can induce axial myopia; however, cryotherapy did not affect normal eye growth and did not prevent the development of lid suturing myopia in piglets.

Influence of destruction of retina-RPE complex on the proliferation of scleral chondrocytes in chicks.

We studied the role of the retina-retinal pigment epithelium (RPE) complex in the proliferation of scleral chondrocytes in chicks. Seventy-two chicks were allocated to one of four groups: intravitreal gentamicin (400 microg) injection (destruction of retina-RPE complex); intravitreal gentamicin injection with goggling; goggling only (form-deprivation myopia); and intravitreal saline injection (control). The chicks were killed and retina-RPE complexes were harvested under a microscope. Retina-RPE complexes were then co-cultured with primary culture of first day scleral chondrocytes in Transwell-COL co-culture systems (Costar), with two different pore sizes (0.4 and 3.0 microm) and serum-deprivation medium. An MTT assay was performed at A550 after 4 days. In the 0.4 microm pore size system, the absorbency at A550 showed no differences between groups. However, in the 3.0 microm pore size system, the absorbency at A550s in the intravitreal gentamicin groups was significantly lower than in the control and the goggle groups (p<0.05), indicating that destruction of the retina-RPE complex inhibited chondrocyte proliferation. The absorbency in the goggle group was higher than in the control group (p<0.05). These results indicate that the retina-RPE complex exerts a positive effect on the proliferation of scleral chondrocytes via a molecule sized between 0.4.and 3.0 microm in diameter.

Accommodation and pupillary response in early-onset myopia among schoolchildren.

PURPOSE: To investigate changes in accommodation and pupillary reaction in early-onset myopia among children. METHODS: An objective infrared optometer and a pupillometer were used to evaluate simultaneously tonic accommodation, accommodative response, accommodative adaptation, and pupil diameter in 19 schoolchildren with early-onset myopia and 15 age-matched emmetropic controls. RESULTS: Tonic accommodation in the early-onset myopes (1.03 D) was significantly less than in the emmetropes (1.37 D) (p < 0.05), whereas accommodative response and accommodative adaptation showed no significant difference between the early-onset myopes and emmetropes. The average pupil diameter after 20 min of dark adaptation in the early-onset myopes was 4.52 mm, which was significantly smaller than that in the emmetropes (5.21 mm) (p < 0.05). During nearwork stimulation, the average pupil diameter further decreased to 3.83 mm in the early-onset myopes and 4.78 mm in the emmetropes (p = 0.003). CONCLUSION: These results suggest that low tonic accommodation and small pupil diameter may play important roles in the pathogenesis of early-onset myopia among schoolchildren.