儿童散光特征分析

目的探讨儿童散光度散光轴向分布情况.方法1%阿托品常规散瞳验光检查2299眼.结果3～10岁儿童散光度多分布在0.25D～2.00D.合例散光占96.35%,反例散光占0.52%,斜轴散光占3.13%.结论3～10岁儿童散光以合例散光为主,斜轴散光次之,极少部分为反例散光.     

学龄前儿童散光特征分析

目的 探讨学龄前儿童散光的类型、程度及轴向分布情况.方法 对3～8岁儿童1980例(2288只眼)行1%阿托品常规散瞳检查,结果进行统计分析.结果 散光类型分布:复性远视散光最多占62.15%、混合性散光18.05%、复性近视散光9.31%.散光程度分布:0.50～2.0DC占75.88%、2.25～3.0DC占15.73%、3.25～4.0DC占6.78%、大于4.25DC占8.39%;散光轴向分布:顺规散光占96.24%、逆规散光占2.84%、斜轴散光占0.92%.所有患儿中弱视患者占58.83%.结论 复性远视散光是学龄前儿童散光的主要类型,以顺规散光为主.散光与弱视密切相关.     

儿童屈光不正中散光情况临床分析

目的:分析3～12岁视力不良儿童210只散光眼的散光度及散光轴向分布情况。方法:对3～12岁视力不良儿童用10g/L阿托品眼液散瞳3d,3次/d,采用带状光检影法加主觉试镜法验光,对检查中检出的散光度≥0.50D的210只散光眼进行统计分析。结果:在3～12岁视力不良儿童210只散光眼中复性远视散光146眼占67.6%,复性近视散光占15.7%,混合散光24眼占11.4%,单纯性散光占5.3%;循规性散光占85.2%,逆规性散光占6.2%,斜轴散光占8.6%。散光程度:0.50～1.00D占54.7%,1.25～2.00D占27.6%,2.25～3.00D占11.0%,3.25～4.00D占6.7%。对称散光128眼占61.0%,不对称散光占39.0%。复性远视散光导致弱视占弱视眼75.8%(75/99);其次为混合散光占14.1%(14/99)。结论:3～12岁视力不良儿童210只散光眼中散光类型以复性远视散光多见,散光轴向分布以循规性散光为主。散光程度多在3.00D以下,散光度随着年龄增加而有下降趋势。     

视力低常学龄前儿童散光特征及分析

目的了解学龄前儿童散光性质、散光度、散光轴向分布情况。方法 1%阿托品眼膏常规散瞳检影验光。结果学龄前儿童散光度大多分布在0.50D～2.00D之间,散光轴向：顺规散光占96.24%,逆规散光占2.14%,斜轴散光1.62%。结论学龄前儿童散光以顺规散光为主,逆规散光次之,斜轴散光最少见,散光情况则以远视散光为主。     

1 238例近视手术患者散光状况分析

目的统计青年近视人群散光状况,分析散光组成和分布特征。方法横断面研究。收集2011年5月至2012年10月在山东医专附属眼科医院准分子激光中心接受近视治疗的1 238例患者（2 476眼）,年龄（21.5±4.1）岁。分别统计这些患者全眼散光度、角膜散光度、晶状体散光度以及散光轴向分布,计算各项所占百分比。结果本组2 476眼中散光眼占65.14%,平均全眼散光度为（0.58±0.62）D,角膜散光占优势地位,平均为（1.06±0.59）D,晶状体散光为（0.58±0.40）D。全眼散光中顺规散光占49.39%,逆规散光占8.19%,斜轴散光占7.56%,单纯近视占34.86%。在角膜散光轴向中,85.26%为顺规性,3.19%为逆规性,6.99%为斜轴散光,4.56%的角膜无散光。在晶状体散光轴向中,4.16%为顺规性,73.10%为逆规性,7.19%为斜轴散光,15.55%的晶状体无散光。引起散光的因素中,单纯角膜散光占13.25%,单纯晶状体散光占1.78%,混合因素引起的散光占81.99%,各因素均无散光占2.99%。结论山东医学高等专科学校附属眼科医院欲行近视手术的青年患者中,角膜散光是眼散光的主要来源,全眼散光和角膜散光以顺规散光为主。     

3-15岁儿童散光分布特征

目的调查3-15岁儿童散光的发生情况,探讨该人群中散光的主要类型,分布规律以及与矫正视力的关系。方法从以人群为基础的3-15岁天津市儿童眼病流行病学调查资料中分层随机抽取3-15岁儿童2070例(4140只眼),进行散光统计分析。结果在2070例儿童中,散光(≥0.5D)者972例,检出率为46.96%;其中0.50-1.00D占71.20%,1.25-2.00D占18.29%。散光轴向分布以顺规散光为主(78.02%)。3-8岁儿童以复性远视散光为主(44.13%),9-15岁儿童以复性近视散光为主(58.51%)。在1542只散光眼中,矫正视力≥0.8者1390眼(90.14%),矫正视力<0.8者152只眼(9.86%)。结论散光在3-15岁人群中的检出率为46.96%,各年龄组散光度分布均以低中度散光为主,3-8岁儿童以复性远视散光为主,9-15岁儿童以复性近视散光为主,高度散光是视力低下的原因之一。     

角膜地形图在预测学龄前儿童散光中的应用

目的探讨角膜地形图检查在预测学龄前儿童散光中的作用。方法分析356例(679只眼)角膜地形图检查散光与睫状肌麻痹后视网膜检影的散光度数和散光轴的相互关系,采用SPSS11统计软件包分析,作配对t检验。结果角膜地形图方法组,循规散光性散光占94.62%,逆规性散光占2.15%,斜轴性散光占3.23%。散瞳检影验光方法组,循规散光性散光占95.74%,逆规性散光占2.78%,斜轴性散光占1.48%。角膜地形图方法组散光度数的分布以1.00~3.00D为主,散瞳检影验光方法组的分布以0.50~2.00D为主。角膜地形图测得的散光度为1.92±0.88D,散瞳检影验光测得的散光度为1.39±0.83D,两者比较差异有统计学意义(t=8.974,P<0.01)。角膜地形图测得的柱镜轴向为101.46±32.57度,散瞳检影验光测得的柱镜轴向为99.73±48.12度,两者比较差别无统计学意义(t=1.08,P>0.05)。结论角膜地形图检查仅反映角膜屈光状况,对验光中散光轴的确定有一定的价值,但临床最终检查结果仍应以睫状肌麻痹后检影作为确定散光度及散光轴的标准。     

3～11岁视力低常儿童散光与弱视分析

目的探讨3~11岁儿童弱视散光类型、散光度分布、散光轴分布、双眼散光轴关系、散光轴与弱视的关系。方法对门诊3~11岁视力低常儿童266例(503只眼)散光状况进行统计分析。结果复性远视散光居多,占71.07%,依次为复性近视散光11.53%,混合散光8.95%,单纯远视5.17%,单纯近视散光3.18%。散光程度0.50~1.00DC占52.18%,依次为1.25~2.00DC占30.02%,2.25~3.00DC占10.54%,>3.00DC占6.76%。顺规散光占94.23%,逆规散光占2.19%,斜向散光占3.58%。双眼散光中,对称散光占95.43%,不对称散光占4.57%。双眼散光占89.46%,单眼散光占10.54%。结论远视性散光是儿童散光的主要类型,顺规散光为主,双眼散光以对称散光多见,散光与弱视关系密切,科学合理矫正儿童散光眼,有利于儿童弱视防治。     

维吾尔族儿童散光眼与偏食的关系探讨

目的:了解6～13岁少年儿童散光状态,并探查儿童散光与偏食之间的关系,为少年儿童视力不良的防治提供依据。方法:对门诊验光者中6～13岁262例485散光眼散瞳验光并分低、中、高度的近视散光和远视散光,同时调查患儿饮食习惯中偏食(不吃肉或不吃蔬菜)情况,观察在各不同程度散光组中偏食习惯的分布。结果:6～13岁少年儿童262例485眼中,近视散光为315眼,占散光总数的64.9%,总的近视散光中不吃肉者为71.4%,不吃蔬菜者为48.2%;远视散光为170眼,占散光总数的35.1%,总的远视散光中不吃肉者占40.6%,不吃蔬菜者占68.8%。散光程度均以低度为主。结论:学龄期儿童中近视散光多于远视散光;轻度屈光度数的散光多于中、高度屈光度数的散光;在近视散光眼患者多不吃肉,而远视散光患者多不吃蔬菜。预防近视和散光应做到养成良好饮食习惯合理搭配食物,儿童有厌食症时应及早治愈。     

5～12岁儿童散光度逐年变化的连续观察

目的　探讨 5～ 12岁儿童散光度连续变化的规律。方法　 3～ 10岁 30 6例 (6 11只眼 )儿童 ,连续观察8年 ,每年一次 ,1%阿托品眼膏散瞳 ,每日 2次 ,连续 3天 ,应用日本 RM- A730 0型自动验光仪 ,每眼检查 3次 ,取平均值 ,将逐年散光度结果进行比较 ,散光度改变 <0 .2 5 D为无变化 ,≥ 0 .2 5 D为增加或减少。结果　 9～ 10岁尤为显著 ,散光度增加的平均值下降达 2 0 .7% ,散光度下降的平均值逐年增加达 35 .3% ,平均减少 0 .5 0 6 D,最多减少1.5 0 D,散光度无变化比值亦逐年增加 ,第 5年达 5 0 % ,各年龄组间有显著性差异。结论　 3～ 10岁儿童散光度的增加随年龄增长而下降 ,减少随年龄增长而上升。     

Clinical evaluation of keratometry and computerised videokeratography: intraobserver and interobserver variability on normal and astigmatic corneas

AIMS—To evaluate intra- and interobserver variability in measurements on normal and astigmatic corneas with keratometry and computerised videokeratography.
METHODS—Keratometric readings with the 10 SL/O Zeiss keratometer and topographic maps with the TMS-1 were obtained by two independent examiners on 32 normal and 33 postkeratoplasty corneas. Inter- and intraobserver coefficients of variability (COR) for measurements of steep and flat meridian power and location, in addition to the magnitude of astigmatism, were assessed.
RESULTS—Compared with TMS-1, the 10 SL/O keratometer showed a superior repeatability in measuring normal corneas (intraobserver COR for keratometry and TMS-1 respectively: 0.22 and 0.30 D for steep meridian power; 0.18 and 0.44 D for flat meridian power; 0.26 and 0.40 D for astigmatism; 5° and 26° for steep meridian location; 5° and 13° for flat meridian location). Astigmatism intraobserver COR (0.20 D and 0.26 D for the two observers) and interobserver COR (0.28 D) of the keratometer for normal corneas was very good and not affected by observers' experience. Repeatability of the TMS-1 on normal corneas was found to be: (a) observer related, and (b) astigmatism related. A novice observer showed a much greater COR (1.62 D for astigmatism, 30° for flat meridian location) compared with the experienced examiner (0.40 D for astigmatism, 13° for flat meridian location). Higher deviation scores were observed for corneas with higher astigmatism. For the postkeratoplasty corneas, again the keratometer achieved superior reproducibility (astigmatism interobserver COR 1.12 D for keratometry, 4.06 D for TMS-1; steep meridian location interobserver COR 10° for keratometry, 34° for TMS-1).
CONCLUSION—Keratometric readings are more reproducible than topographic data both for normal and postkeratoplasty corneas. The two instruments should not be used interchangeably especially on highly astigmatic corneas. For the TMS-1, users with the same level of experience should be employed in clinical or experimental studies.

Keywords: keratometry; computerised videokeratography; astigmatic corneas     

Combined astigmatic keratotomy with corneal valvular incision in the treatment of high surgical astigmatism

Background: Astigmatic keratotomy is used conventionally to correct moderate surgical astigmatism. However, cases with very high surgical astigmatism due to wound compression can show a dramatic response to relaxing keratotomies made in the steeper meridian. The effect obtained cannot be predicted pre-operatively by using standard nomograms. Methods: Coupled arcuate keratotomies combined with corneal valvular incisions were performed in a case of high astigmatism post-cataract surgery. Results/Conclusion: Coupled arcuate keratotomies were combined with a corneal valvular incision enabled a surgical correction of nearly 9 D of astigmatism.     

Subjective refraction using power vectors by updating a conventional phoropter with a Stokes lens for continuous astigmatic power generation

Purpose

To implement a pure power vector method for monocular subjective refraction using a regular phoropter with the only modification being the inclusion of a Stokes lens. The proposed methodology was tested with three different Stokes lenses, and the results were compared with conventional clinical refraction procedures.

Methods

Power vector subjective refraction was performed by attaching a Stokes lens to the Risley prism holder. Stokes lenses allow for pure astigmatic compensation in the form of the J₀, J₄₅ components while the spherical lenses in the phoropter allow determination of the spherical component in the form of M (spherical equivalent). The proposed routine is presented step-by-step using three Stokes lenses having different astigmatic powers.

Results

Monocular subjective refraction was performed on 26 healthy subjects with a mean age of 44 ± 16 years, mean spherical equivalent of −0.56 D (range −5.50 to +2.38 D) and refractive astigmatism ≤1.50 D. No differences were found between the results obtained with the conventional technique versus the vector-based procedure for the spherical equivalent (p = 0.28) or astigmatic components (p = 0.34). In addition, visual acuity (VA) was equivalent through the refractions measured with the conventional and vector procedures (p = 0.12). Repeatability coefficients for J₀ and J₄₅ with the new vector methodology were <0.38 D.

Conclusions

The proposed routine could be helpful for cases where it is difficult to get a valid starting point for conventional refraction (e.g., irregular corneas and media opacities), for testing facilities with limited resources/equipment and/or for motivated clinicians who wish to know about alternative methods of refractive error determination.     

眼散光轴与角膜散光轴对LASIK矫正散光效果的影响

目的研究眼散光轴和角膜散光轴对准分子激光原位磨镶术(laser in situ keratomileusis,LASIK)矫正散光效果的影响。方法对73例(114眼)行LASIK手术的近视散光患者进行回顾性分析,按照眼散光和角膜散光轴的差异分为<15°组(68眼)和≥15°组(46眼),分析2组LASIK术后散光的矫正效果及角膜散光与眼散光之间的关系。结果术前<15°组和≥15°组的眼散光分别为(-0.94±0.36)D和(-0.82±0.34)D,2组间差异无统计学意义(t=-1.02,P>0.05);角膜散光分别为(-1.31±0.41)D和(-1.18±0.49)D,2组间差异无统计学意义(t=1.599,P>0.05)。术前角膜散光与眼散光有统计学相关性(r=0.527,P<0.01),但术后无统计学相关性(r=-0.024,P>0.05)。<15°组术后散光矫正效果较好,2组间有统计学意义(t=-2.017,P<0.05)。术后眼散光量与偏心量有统计学相关性(r=0.395,P<0.01),而角膜散光则与偏心量没有统计学相关性(r=-0.133,P>0.05)。结论眼散光和角膜散光轴的差异影响LASIK矫正散光的效果。LASIK术后角膜形态改变,角膜散光与眼散光之间的关系也发生改变。     

Long-term results of corneal wedge resections for the correction of high astigmatism

We retrospectively evaluated 41 corneal wedge resections, performed for the correction of high astigmatism in 40 patients who were spectacle and contact lens intolerant. Keratometric astigmatism decreased from an average of 11.7 diopters (range 5 to 22.5 D) preoperatively to 3.5 diopters (range 0 to 10 D) postoperatively, representing a mean reduction of 8.2D (range 0 to 16.5), or 70%. The length of follow-up averaged 11 months. Twenty-five, 15 and 9 cases had a follow-up of at least 3, 5 and 10 years, respectively. In 16 cases the keratometry readings remained stable over the years. However, in 1 case of Fuchs' endothelial dystrophy (follow-up 13 years) and 5 cases of keratoconus (follow-up 3, 4, 12, 13 and 14 years) the astigmatism gradually increased during the various follow-up periods. In 3 other cases the astigmatism gradually decreased over the years. Corneal wedge resection is an effective technique for managing high corneal astigmatism. The results remain stable over the years except in some patients with keratoconus.     

Refractive and structural changes in infantile periocular capillary haemangioma treated with propranolol

Purpose

To evaluate the optical and anatomical effects of oral propranolol treatment for infantile periocular capillary haemangioma.

Methods

All children diagnosed with infantile capillary haemangioma in 2008–2010 at a tertiary paediatric medical centre underwent comprehensive evaluation, including imaging, by a multidisciplinary team followed by oral propranolol treatment. Clinical follow-up was performed regularly until the lesions disappeared. Main outcome measures included changes in anatomical extraocular extension, refractive sphere and cylindrical power, and spherical equivalent in the involved eye before and after treatment and between the two eyes.

Results

A total of 30 patients (8 male; mean age at diagnosis, 1.6±2.8 months) participated. The lesions affected the left eye in 53.3% and were located preseptally in 83.3%. Four patients (13.3%) received steroids before propranolol. A treatment dosage of 2 mg/kg per day was started at mean age 5.0±4.5 months, 3.3±4.3 months from disease onset. Side effects occurred in 11 patients and warranted a dose reduction (to 1 mg/kg per day) in 3 and treatment termination in 1. Findings were significant for mean reduction in involved extraocular area (P<0.0001), post-treatment reduction in mean cylindrical power in involved eyes (P=0.02), pre- and post-treatment differences in mean cylindrical power between involved and uninvolved eyes (P=0.02 and P=0.01, respectively), and post-treatment change in absolute values of mean spherical power between involved and uninvolved eyes (P=0.025).

Conclusions

Early diagnosis of infantile periocular capillary haemangioma and prompt treatment with propranolol lead to a significant reduction in the involved ocular area, in astigmatism, and prevent ocular/facial disfiguration/deformation, without rebound. Propranolol is recommended as the preferred treatment compared with other accepted therapies.     

Femtosecond laser astigmatic keratotomy for postkeratoplasty astigmatism

CASE REPORT: Two eyes of 2 patients with high astigmatism following penetrating keratoplasty were treated with femtosecond laser-assisted paired arcuate keratotomies in the donor cornea. Outcome measures included best-corrected visual acuity, refraction, keratometry, and topographic findings. The preoperative cylinder was 8.5 diopters (D) in the first case and 7.0 D in the second case. Respectively, the postoperative cylinder improved to 4.9 D after a follow-up of 8 months and to 4.3 D after a follow-up of 7 months. Best-corrected visual acuity improved from 20/100 to 20/30 in the first case and from 20/200 to 20/60 in the second case. No complications were encountered; no microperforations were observed, and neither graft rejection nor failure occurred. COMMENTS: The results of astigmatic keratotomy performed with femtosecond laser were reliable and predictable. Femtosecond astigmatic keratotomy may prove to be a safe procedure with satisfactory results.     

Cardinal points and generalizations

In the presence of astigmatism a focal point typically becomes the well‐known interval of Sturm with its pair of axially‐separated orthogonal line singularities. The same is true of nodal points except that the issues are more complicated: a nodal point may become a nodal interval with a pair of nodal line singularities, but they are not generally orthogonal, and it is possible for there to be only one line singularity or even none at all. The effect of astigmatism on principal points is the motivation behind this paper. The three classes of cardinal points are defined in the literature in a disjointed fashion. Here a unified approach is adopted, phrased in terms of rays and linear optics, in which focal, nodal and principal points are defined as particular cases of a large class of special structures. The special structures arising in the presence of astigmatism turn out to be described by mathematical expressions of the same form as those that describe nodal structures. As a consequence everything that holds for nodal points, lines and other structures now extends to all other special points as well, including principal points and the lesser‐known anti‐principal and anti‐nodal points. Thus the paper unifies Gauss’s and Listing’s concepts of cardinal points within a large class of special structures and generalizes them to allow for refracting elements which may be astigmatic and relatively decentred. A numerical example illustrates the calculation of cardinal structures in a model eye with astigmatic and heterocentric refracting surfaces.     

Corneal astigmatic outcomes after femtosecond laser-assisted cataract surgery combined with surface penetrating arcuate keratotomies

AIM: To evaluate corneal astigmatic outcomes of femtosecond laser-assisted arcuate keratotomies (FAKs) combined with femtosecond-laser assisted cataract surgery (FLACS) over 12mo follow-up. METHODS: Totally 145 patients with bilateral cataracts and no ocular co-morbidities were recruited to a single-centre, single-masked, prospective randomized controlled trial (RCT) comparing two monofocal hydrophobic acrylic intraocular lenses. Eyes with corneal astigmatism (CA) of >0.8 dioptres (D) received unpaired, unopened, surface penetrating FAKs at the time of FLACS. Visual acuity, subjective refraction and Scheimpflug tomography were recorded at 1, 6, and 12mo. Alpins vectoral analyses were performed. RESULTS: Fifty-one patients (61 eyes), mean age 68.2±9.6y [standard deviation (SD)], received FAKs. Sixty eyes were available for analysis, except at 12mo when 59 attended. There were no complications due to FAKs. Mean pre-operative CA was 1.13±0.20 D. There was a reduction of astigmatism at all post-operative visits (residual CA 1mo: 0.85±0.42 D, P=0.0001; 6mo: 0.86±0.35 D, P=0001; and 12mo: 0.90±0.39, P=0.0001). Alpins indices remained stable over 12mo. Overall, the cohort was under-corrected at all time points. At 12mo, 61% of eyes were within ±15 degrees of pre-operative astigmatic meridian. CONCLUSION: Unpaired unopened penetrating FAKs combined with on-axis phacoemulsification are safe but minimally effective. CA is largely under-corrected in this cohort using an existing unmodified nomogram. The effect of arcuate keratotomies on CA remained stable over 12mo.