Effect of experimental scleral shortening on axial length of the rabbit eye

PURPOSE: To evaluate the change of axial length (AL), intraocular pressure (IOP), and corneal astigmatism after scleral shortening with scleral invagination in the rabbit eye. METHODS: The authors performed scleral shortening (3 mm) with scleral invagination in two groups of 6 eyes each: 180 degrees (group 1) and 360 degrees (group 2). RESULTS: Average AL shortening was more prominent in group 2 (0.5 +/- 0.17 mm) than in group 1 (0.37 +/- 0.29 mm), but the difference was not statistically significant. IOP increased immediately after the procedure and was maintained at a high level through 2 months postoperatively. Induced corneal astigmatism was more prominent in group 1 than in group 2. The difference was statistically significant in group 1 (p<0.05) but not in group 2. CONCLUSIONS: In the scleral shortening with scleral invagination procedure, a large amount of scleral invagination resulted in more shortening of axial length, but there was more corneal astigmatism in 180-degree invagination of the sclera than in 360-degree. Further research is required to determine the effect of the extent of scleral invagination on the change of these values.     

Oculometric characteristics of extreme hypermetropia in two faroese families.

PURPOSE: To describe and analyze the oculometric features of small eyes with high hypermetropia in two Faroese families, with emphasis on refractive components. METHODS: Members of the two families (N=40; age, 1 to 77 years), including 15 cases of extreme hypermetropia (+7.5 to +19.25 D), had an ophthalmic evaluation including refractometry, keratometry, and axial ocular measurements using A-scan ultrasound. Eye-wall thickness was assessed using B-scan. Nonparametric statistics were used, mainly the Mann-Whitney U test. RESULTS: In the two families, there were six and nine probands, respectively, with hypermetropia more than +7 D and short eyes as defined by axial eye lengths <21 mm. The median corrected visual acuity was 0.4 (range, 0.2 to 0.9). Gross fundus abnormalities were not observed. All 15 had a short posterior segment with a thick eye wall and a relatively thick lens. Furthermore, steep and rather small corneas were present. In one of the families, 70% of the affected had a corneal curvature radius of < or =7.0 mm. Five probands from family 2 were labeled as possibly affected because of hypermetropia and borderline axial length findings (21 to 22 mm). The remaining 20 subjects had visual acuity and oculometric findings within physiologic limits. CONCLUSIONS: The axial measurement features in our series of highly hypermetropic eyes mainly presented as an extension downward from the hypermetropic bottom line of the normal distribution. The axial shortness of the eyes was primarily the result of a short posterior eye segment ("posterior microphthalmos"). A steep cornea was a feature in most small eyes in our series, particularly in one family branch.     

Human eye ocular component analysis for refractive state and refractive surgery

AIM: To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial length. METHODS: An effective eye model was introduced by the ocular components of human eye including refractive indexes, surface radius (r1, r2, R1, R2) and thickness (t, T) of the cornea and lens, the anterior chamber depth (S1) and the vitreous length (S2). Gaussian optics was used to calculate the change rate of refractive error per unit amount of ocular components of a human eye (the rate function M). A new criterion of myopia was presented via an effective axial length. RESULTS: For typical corneal and lens power of 42 and 21.9 diopters, the rate function Mj (j=1 to 6) were calculated for a 1% change of r1, r2, R1, R2, t, T (in diopters) M1=+0.485, M2=-0.063, M3=+0.053, M4=+0.091, M5=+0.012, and M6=-0.021 diopters. For 1.0 mm increase of S1 and S2, the rate functions were M7=+1.35, and M8=-2.67 diopter/mm, respectively. These rate functions were used to analyze the clinical outcomes in various applications including laser in situ keratomileusis surgery, corneal cross linking procedure, femtosecond laser surgery and scleral ablation for accommodation. CONCLUSION: Using Gaussian optics, analytic formulas are presented for the change of refractive power due to various ocular parameter changes. These formulas provide useful clinical guidance in refractive surgery and other related procedures.     

角膜塑形术对近视患者立体视觉和调节参数及眼生物学参数的影响

目的：探讨角膜塑形术对近视患者立体视觉、调节参数和眼生物学参数的影响。

方法：分析2016-01/2017-05在我院接受治疗的65例130眼青少年近视患者的临床资料,按照等效球镜度分为高度近视组、中度近视组和轻度近视组。比较配戴角膜塑形镜前后近视患者立体视觉、调节参数和眼生物学参数的变化。

结果：三组患者远近视力差值、立体视锐度、调节幅度、调节灵敏度水平比较,差异均有统计学意义(P<0.05)。近视患者治疗后裸眼视力(LogMAR)、球镜度数、柱镜度数明显低于戴镜前,差异均有统计学意义(P<0.05)。近视患者配戴角膜塑形镜后眼压、中央角膜厚度与戴镜前比较,差异无统计学意义(P>0.05)。戴镜后患者角膜曲率低于配戴前,差异有统计学意义(P<0.05)。眼轴长度高于治疗前,差异具有统计学意义(P<0.05)。

结论：角膜塑形术可改善青少年患者的近视和散光,且能改善角膜曲率和延缓眼轴增长。     

Association between accommodative accuracy, hypermetropia, and strabismus in children with Down's syndrome.

PURPOSE: A significant proportion of children with Down's syndrome have been shown to have reduced accommodation. The purpose of this study was to investigate any association between reduced accommodation and refractive error, strabismus, visual acuity, and other ocular parameters. METHODS: Subjects were children with Down's syndrome enrolled in a longitudinal cohort to monitor visual development. Twenty-seven children with accurate accommodation were age-matched to children with reduced accommodation based on their most recent assessment for which a full, reliable data set was available. Each child was used only once for matching. Cross-sectional ocular and visual data were analyzed using chi or Fisher's exact test, or the Mann-Whitney U test for (non-normally distributed) quantitative data. RESULTS: Children with under-accommodation were statistically more likely to have moderate/high hypermetropia (> or = +3.00 D) and to be strabismic (most with esotropia). No significant difference between the groups was found for any other ocular parameters. CONCLUSIONS: This study demonstrates the marked association between under-accommodation, hypermetropia, and strabismus in children with Down's syndrome. No causal relation can be demonstrated with these data, but findings suggest that the link between under-accommodation and hypermetropia (and between accurate accommodation and emmetropia) is present in early infancy.     

The effect of mydriasis from phenylephrine on corneal shape

Purpose: A previous study reported that pharmacologically‐dilated pupils changed the corneal shape. Researchers used mydriatic agents with significant cycloplegic effect. The current study investigates the effect of mydriasis on corneal shape using phenylephrine alone, where phenylephrine has minimal effect on the accommodative system and whether corneal topography can be done after pupil dilation. Methods: Forty‐four young healthy subjects with one eye randomly selected for mydriasis were used in this study. Twenty‐two received one drop of 2.5% phenylephrine (group 1); the other 22 subjects had one drop of 0.4% benoxinate instilled prior to the application of 2.5% phenylephrine (group 2). They were matched for age and refractive error. Anterior chamber depth, pupil size and corneal parameters were compared before and after mydriasis. The corneal parameters included best‐fit sphere (BFS), surface asymmetry index (SAI), surface regularity index (SRI) and the axial and tangential powers in the form of flattest and steepest powers, and in the form of M, J₀, and J₄₅ vector presentation. Results: Group 1 and group 2 subjects had similar pre‐mydriatic baseline ocular parameters. The mean (± SD) pupil dilation was 1.24 ± 0.59 mm for group 1 and 1.80 ± 0.95 mm for group 2. The dilation was significantly larger in group 2 (unpaired t‐tests: t = 2.36, p = 0.02). There were no significant changes in corneal parameters from mydriasis in either group. Conclusions: Previous investigations used mydriatic agents, which affected not only the pupil size but also accommodation. The current study found that mydriasis from phenylephrine, with minimal effect on accommodation, did not result in significant corneal alteration, and corneal topography can be measured after pupil dilation with phenylephrine.     

巩膜环扎术后眼球的屈光改变及生物测量

目的 :观察环扎术后眼球屈光状态的改变。方法 :前瞻性研究了 35例孔源性视网膜脱离巩膜环扎术患者。分别在术前 1天、术后 1 0天测量屈光度、前房深度、晶状体厚度、眼轴长度、角膜水平及垂直曲率。结果 :巩膜环扎术后屈光度向负值偏移 (- 0 75± - 0 2 5)D。角膜水平曲率变大、前房变浅 (P <0 0 5)。而角膜垂直曲率和晶状体厚度变化不明显 (P >0 0 5)。控制环扎带平均 65mm长时 ,眼内嵴高 3～ 6D ,眼轴长度平均增加 1 36mm。结论 :巩膜环扎术后眼屈光度向负值偏移。眼轴长度的增加是偏移的主要原因     

藏族年龄相关性白内障患者眼球生物学参数特征分析

目的：比较藏族与汉族年龄相关性白内障患者眼球生物学参数的差异,分析藏族患者眼球生物学参数的分布特征。

方法：回顾性队列研究。收集2019-01/2020-12就诊于我院的年龄相关性白内障患者661例1 030眼,其中藏族患者483例739眼,汉族患者178例291眼。术前所有患者均采用IOL Master 500测量眼轴长度、前房深度、角膜曲率、散光及散光轴向。

结果：藏族年龄相关性白内障患者眼轴长度为23.33(22.81,23.86)mm,前房深度为3.04(2.79,3.30)mm,散光度为0.73(0.47,1.07)D,平均角膜曲率为43.89±1.35 D,较汉族患者眼轴短,角膜曲率小(均P<0.05)。藏族患者的年龄与眼轴长度和前房深度均呈负相关,而与平均角膜曲率呈正相关(均P<0.05)。藏族患者中男性患者较女性患者眼轴更长、前房更深、角膜更平坦(均P<0.05)。

结论：藏族与汉族年龄相关性白内障患者的眼球生物学参数存在差异,不同年龄和性别藏族患者眼球生物学参数的分布有所变化。     

角膜塑形镜矫治青少年近视散光的疗效及对角膜内皮细胞的影响

目的：探讨角膜塑形镜矫正青少年近视的临床效果及对角膜内皮细胞的影响。方法：随机在我院选择400例800眼明确诊断为近视的青少年患者,平均年龄为11．5±2．3岁,其中男239例,女161例,根据治疗方法随机分为角膜塑形组和框架眼镜组,分别为167例334眼和233例466眼,本试验所研究的数据包括：（1）疗效：裸眼视力、角膜曲率、眼轴长度、屈光度等;（2）角膜内皮细胞：角膜内皮细胞计数、密度、角膜点染程度以及角膜中央厚度等。观察时间分别为配戴后1d,1、6、12、24mo,了解角膜塑形镜治疗青少年近视的临床效果及对角膜内皮细胞的影响,采用方差分析进行组间和组内的比较。结果：框架眼镜组可在配戴眼镜后视力达正常,角膜塑形组患者在1 mo后视力达到正常水平。经2 a的配戴后角膜塑形镜组患者的角膜曲率、屈光度明显降低,分别为40.09±0．31、0．23±0．06 D,而框架眼镜组则有显著上升,两组比较差异具有统计学意义（P＜0．05）;两组患者眼轴长度治疗后的第1 mo较治疗前均有轻度增加,但差异无统计学意义（P＞0．05）;治疗2a后,两组的眼轴长度分别为23．96±0．38、26．49±0．88 mm,眼轴长度差异有统计学意义（P＜0．05）。角膜中央厚度在治疗2a 后则分别为527．33±27．69、526．98±26．89μm,2a后的角膜中央厚度比较,两组差异无统计学意义（P＞0．05）,有关两组患者治疗后1 mo的角膜内皮细胞计数和密度较治疗前均有减少,但差异无统计学意义（P＞0．05）。结论：角膜塑形矫正青少年近视的临床效果好,对角膜内皮细胞的影响较小,且能够有效控制近视发展。     

Ocular rigidity in living human eyes

PURPOSE: To measure the rigidity coefficient of a large number of subjects at clinically encountered intraocular pressures (IOPs) and to examine the possible correlation of ocular rigidity with other factors, such as the age of the patients, ocular parameters (axial length and corneal thickness), and pathologic conditions affecting the eye. METHODS: The pressure-volume relationship and the ocular rigidity coefficient (K) were determined in 79 eyes undergoing cataract surgery, by injecting 200 microL of saline solution (in steps of 4.5 microL) through the limbus into the anterior chamber, while continually monitoring the IOP with a transducer, up to the limit of 60 mm Hg. Data within an IOP range of 10 to 35 mm Hg were used to calculate the scleral rigidity coefficient. All measurements were taken at the same time of day, to eliminate any possible diurnal variation. RESULTS: The mean ocular rigidity coefficient was 0.0126 mm Hg/microL (95% confidence interval [CI], 0.0112-0.0149). A statistically significant positive correlation between the rigidity coefficient and age of the patient was found (P = 0.02), whereas similar findings were not observed for the examined ocular parameters (axial length, P = 0.09; and corneal thickness, P = 0.12). No correlation was found for patients with diabetes mellitus (P = 0.39), age-related macular degeneration (P = 0.55), and hypertension (P = 0.45). CONCLUSIONS: The present study provides quantitative data on the ocular rigidity coefficient based on measurements in a large series of living human eyes. A positive correlation between the ocular rigidity coefficient and the patient's age was documented.     

OA-2000测量的长眼轴白内障患者眼球生物学参数分析

目的 分析长眼轴白内障患者眼球生物学参数特点。设计回顾性病例系列。研究对象2021年6月至2022年4月在北京同仁医院眼科就诊的白内障患者1000例(1000眼)。方法采用OA-2000测量眼轴长度(AL),根据测得AL将患者分为正常眼轴对照组(22 mm≤AL<26 mm)和长眼轴组(AL≥26 mm),长眼轴组根据眼轴长度进一步分为4组:A组(26 mm≤AL<28mm)187眼;B组(28 mm≤AL<30 mm)140眼;C组(30 mm≤AL<32 mm)130眼;D组(AL≥32 mm)93眼。对正常眼轴及长眼轴组眼、长眼轴各亚组的眼球生物学参数进行比较,并分析眼轴长度与眼球生物学参数、年龄与眼球生物学参数之间的相关性。主要指标AL、角膜曲率(Kf、Ks、Km)、前房深度(ACD)、晶状体厚度(LT)、角膜横径(WTW)。结果长眼轴组患者Kf、Ks、Km、角膜散光、ACD、LT、WTW分别为(43.07±1.61)D、(44.65±1.71)D、(43.91±1.62)D、(1.52±0.77)D、(3.28±0.47)mm、(4.55±0.41)m...     

两种巩膜隧道切口超声乳化白内障吸除手术的疗效比较

目的 研究新型“L”形不缝合巩膜隧道切口超声乳化白内障吸附人工晶状体植入术的临床疗效。方法 将68例（68只眼）老年性白内障患者分为两组,分别行“L”形巩膜隧道切口（34只眼）和3．2mm巩膜隧道切口（34只眼）超声乳化白内障吸除术,并分别植入光学部直径6mm的聚甲基丙烯酸甲酯硬性及丙烯酸酯聚合物折叠式人工晶状体。随访视力、角膜曲率和角膜地形图的改变。结果 术后1d至3个月两组视力、手术性角膜散光度数及轴向变化比较,差异均无显著意义（P＞0．05）;两组术后角膜地形图与术前比较无明显改变。结论“L”形巩膜隧道切口超声乳化白内障吸除术与3．2mm巩膜隧道切口手术的疗效基本相同,而且操作简便、安全、手术费用低廉,值得临床推广使用。     

后巩膜加固术加固条带长度估算的研究

 目的 比较单条兜带式后巩膜加固术异体巩膜长度三种计算方法的准确性。设计 技术评价。研究对象 2008年12月-2010年2月北京同仁医院病理性近视眼62例（65眼）。方法  所有患者接受后巩膜加固术。术前检查屈光度、角膜曲率、前房深度、眼轴等。后巩膜加固术异体巩膜长度计算采用3种方法,方法1和方法2根据眼球几何计算方法设计,前者主要利用前房深度值,后者主要利用角膜曲率值;方法3根据术中测量实际应用的异体巩膜长度,建立回归公式进行计算。三种方法计算值分别与实际应用异体巩膜长度比较。主要指标 异体巩膜长度、眼轴、角膜曲率、前房深度、屈光度。结果 65眼应用的实际异体巩膜平均长度（47.8±4.0）mm。对异体巩膜长度的预测结果方法1为（58.7±8.0）mm,与实际差值（10.8±5.2）mm;方法2为（58.6±8.0）mm,与实际差值（10.7±5.2）mm;方法3为（47.8±3.3）mm,与实际差值（0.00±2.22）mm。方法3建立的回归方程：异体巩膜条带长度=9.576+1.271×眼轴。方法1、2、3与实际值的相关系数（r值）分别为0.822、0.829、0.835。结论 单条兜带式后巩膜加固术需要的异体巩膜长度可通过以眼轴为基础的回归公式计算,未建立回归公式前可根据几何公式进行推算。（眼科,2013,22：53-57）     

原发性急性闭角型青光眼合并白内障超乳术后的屈光误差及其相关影响因素

目的：对比原发性急性闭角型青光眼(acute primary angel-closure glaucoma,APACG)合并白内障患者及单纯白内障患者行PHACO+IOL术后3mo的屈光误差(refraction error, RE),并分析影响两组术后屈光误差相关的眼球生物学参数(眼轴、角膜曲率、前房深度)。

方法：前瞻性、非随机性病例对照研究。APACG合并白内障组为试验组,单纯白内障组为对照组,每组各30例30眼,测量眼压、眼轴长度、角膜曲率、前房深度,利用SRK-Ⅱ公式计算预留屈光度。以术后3mo的主觉验光结果作为术后屈光度,减去术前预留屈光度,即为屈光误差(RE,<-0.50D或>+0.50D; -0.50～+0.50D不认为存在屈光误差 )。采用独立样本t检验比较两组间屈光误差的差别及比较两组间的相关参数如眼轴、角膜曲率、前房深度的差异,采用配对样本t检验分别比较两组术前术后相关参数如眼轴、角膜曲率、前房深度的差异。

结果：白内障组术后的平均屈光误差为-0.46±0.46D,其中近视性屈光误差共24例(80%),远视性屈光误差共6例(20%); APACG组术后的平均屈光误差为+0.56±0.79D,其中近视性屈光误差共9例(30%),远视性屈光误差共21例(70%),两组术后屈光误差的差异具有统计学意义(P<0.05)。两组内的术前术后生物参数比较：白内障组术前眼轴长度23.55±0.47mm,术后23.56±0.48mm,眼轴长度变化差异无统计学意义(P>0.05); APACG组术后的眼轴长度21.52±0.54mm,较术前的眼轴长度(21.71±0.46mm)变短,差异有统计学意义(P<0.05)。白内障组术后前房深度4.09±0.38mm,较术前前房深度(2.71±0.24mm)明显增加,差异有统计学意义(P<0.05); APACG组术后的前房深度3.55±0.35mm,较术前前房深度(1.90±0.23mm)明显增加,差异有统计学意义(P<0.05)。白内障组术前平均角膜曲率43.93±0.95D,术后43.92±0.95D,平均角膜曲率变化差异无统计学意义(P>0.05); APACG组术前平均角膜曲率44.71±0.84D,术后44.70±0.9D,平均角膜曲率变化差异无统计学意义(P>0.05)。两组间的相关生物参数比较：APACG组术后眼轴变短,与单纯白内障组眼轴变化量比较,差异有统计学意义(P<0.05); APACG组术后前房加深明显,与单纯白内障组前房加深量比较有统计学意义(P<0.05)。

结论：对比单纯白内障患者,APACG合并白内障患者行PHACO+IOL术后的屈光误差大,且呈远视漂移,与APACG患者术后眼轴变短及前房深度增加更明显相关。     

孔源性视网膜脱离行巩膜外环扎和巩膜外加压术对眼球结构和眼压的影响

目的：观察巩膜外环扎术和巩膜外环扎联合巩膜外加压术对孔源性视网膜脱离(rhegmatogenous retinal detachment,RRD)患者眼球结构和眼压的影响。

方法：选取2014-05/2017-05在我院住院行手术治疗的RRD患者240例240眼,其中接受巩膜外环扎术100眼(巩膜外环扎术组),接受巩膜外环扎联合巩膜外加压术140眼(联合组)。术前、术后2、4、12wk,检测眼压、角膜厚度、角膜水平和垂直曲率、前房深度、晶状体厚度、眼轴长度、睫状体厚度及小梁虹膜夹角度数。

结果：术后12wk,两组患者240眼均获得解剖复位。术后2wk,两组眼压、角膜厚度、角膜水平和垂直曲率、晶状体厚度、睫状体厚度均较术前显著增加,前房深度及小梁虹膜夹角度数均较术前明显减小,差异均有统计学意义(P<0.05)。两组患者术后视力均较术前改善,且术后2wk联合组视力明显优于巩膜外环扎术组,差异均有统计学意义(P<0.05)。

结论：巩膜外环扎术和巩膜外环扎联合巩膜外加压术对角膜、前房、房角、晶状体厚度及小梁虹膜夹角度数在早期均有显著影响,巩膜外环扎联合巩膜外加压术对眼压的影响时间长,应予以关注。     

Influence of accommodation on the anterior and posterior cornea

PURPOSE: To evaluate whether significant change occurs in the topography of the anterior or posterior cornea or in corneal thickness with accommodation. SETTING: Contact Lens and Visual Optics Laboratory, School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia. METHODS: Corneal data were acquired for 12 young, healthy emmetropic subjects under 2 accommodation levels (relaxed and approximately 5.0 diopters) using a rotating Scheimpflug camera. Anterior and posterior corneal elevation and sagittal curvature data as well as pachymetry data were analyzed to evaluate changes associated with accommodation. Corneal elevation data were also analyzed using a recentering procedure designed to minimize the effect of ocular micromovements between measurements. RESULTS: Changes in corneal parameters resulting from accommodation were small and generally insignificant. The mean change in pachymetry was 0.49 microm +/- 2.62 (SD) across an 8.0 mm pachymetry map. No significant change was found in the best-fit corneal spherocylinder (anterior and posterior cornea) (P>.05). Small changes were found in the corneal cylinder axis, indicative of small cyclotorsional eye movements accompanying accommodation. The mean changes in corneal elevation were 0.09 +/- 0.41 microm (anterior cornea) and 0.17 +/- 0.65 microm (posterior cornea). Only 0.50% (anterior cornea) and 0.27% (posterior cornea) of corneal elevation data points exhibited a statistically significant change with accommodation. Recentering the corneal elevation data led to a reduction in the magnitude of change in corneal elevation with accommodation. CONCLUSIONS: Small cyclotorsional eye movements occurred with accommodation. When these eye movements were accounted for in data analysis, no consistent significant change in the topography of the cornea was found with accommodation across an 8.0 to 9.0 mm corneal diameter.     

Axial length and refractive error in X-linked retinoschisis

PURPOSE: To examine the relationship between axial length and refractive error in patients with X-linked retinoschisis. DESIGN: To determine whether the hypermetropia frequently found in patients with X-linked retinoschisis is axial hypermetropia. METHODS: The axial length and refractive error were measured in 29 right eyes of 29 patients. The patients were divided into two groups: a juvenile group with ages <13 years (12 eyes) and an adult group with ages > or =13 years (17 eyes). The axial length of the right eye of 30 adult men without eye diseases whose refractive error ranged from +/- 1.0 diopter served as controls. RESULTS: In the adult patient group, the refractive error was significantly more hypermetropic and the axial length was significantly shorter than was the normal adult group (P <.001). CONCLUSION: These results strongly suggest that the hypermetropia in patients with X-linked retinoschisis is axial hypermetropia.     

Corneal thickness and axial length

PURPOSE: A thin central cornea has been reported to be a risk factor for developing primary open-angle glaucoma among ocular hypertensive eyes. A thin scleral bed of lamina cribrosa seen in deeply excavated optic nerves in glaucomatous eyes is a quintessential finding in advanced glaucomatous eyes. Association between thin cornea and weak sclera contributing to vulnerability of lamina cribrosa has been postulated. The purpose of this study is to determine whether there is an association between corneal thickness and axial length of human eyes in a clinical setting. DESIGN: This is an observational, retrospective cross-sectional study. METHODS: The ocular parameters of 1,084 consecutive eyes with both corneal thickness and axial length measurements were analyzed and compared by age, gender, and race. RESULTS: In the total patient study group, there was no statistically significant association between central corneal thickness and axial length. Subgroup analysis by age, gender, and race also failed to show an association. CONCLUSIONS: Central corneal thickness and axial length are independent occurrences. Thin corneas are not associated with longer eyes.     

年龄相关性白内障患者眼轴和角膜曲率对角膜生物力学的影响

目的：探讨应用可视化角膜生物力学分析仪(corneal visualization Scheimpflug technology,Corvis ST)研究不同眼轴长度(axial length,AL)和角膜曲率的老年人角膜生物力学特点。

方法：横断面研究。收集拟接受白内障手术的患者161例297眼,将研究对象按AL值的不同进行分组：22～24mm者190眼,24～26mm者54眼,>26mm者53眼。将AL为22～24mm、K值42～44D之间的研究对象按性别进行分组,男44眼,女44眼; 对AL为22～24mm的研究对象按K值的不同分组：42～44D者88眼,>44D者102眼; 应用可视化角膜生物力学分析仪(Corvis ST)测量角膜生物力学参数,并对不同性别、不同眼轴、不同角膜曲率患者的角膜生物力学参数进行比较性分析,采用单因素方差分析、独立样本t检验等对数据进行统计,并分析各组生物力学参数间的相关性。

结果：男女之间角膜生物力学参数比较,差异无统计学意义(P>0.05),不同角膜曲率间只有第一压平长度、第二压平长度比较,差异有统计学意义(P<0.05)。不同眼轴长组间：第二压平速度、最大形变幅度、中央角膜厚度、眼压的组间比较,差异有统计学意义(P<0.05)。眼轴与最大形变幅度及眼压呈线性正相关(r=0.429、0.278,P<0.001),与中央角膜厚度、第二压平速度呈线性负相关(r=-0.291、-0.415,P<0.001)。

结论：角膜曲率和AL可能是使角膜力学属性发生改变的角膜相关参数,角膜厚度会随着眼轴的增长呈现变薄的趋势,角膜也较容易发生形变,而且眼压也会随着眼轴的增长而逐渐增高。     

先天性纤维血管瞳孔膜患儿的眼部生物学参数和屈光状况

目的：:观察先天性纤维血管瞳孔膜（CFPM）患儿的临床表现、术前生物学参数及术后屈光状况。方法：:回顾性系列病例研究。分析2016年7月至2019年12月在温州医科大学附属眼视光医院杭州院区接受手术治疗的CFPM患儿13例（15眼）的临床资料,其中11例单眼发病,2例双眼发病。记录患儿手术年龄、合并症、眼部生物学参数、...