翼状胬肉侵入角膜程度对屈光状态的影响

目的通过对翼状胬肉侵入角膜内程度对角膜屈光状态影响的分析，为治疗、手术提供参考依据。方法93例（97眼）门诊施行胬肉手术者，术前进行屈光度、视力检查。术后2月进行屈光度和视力检查，进行术前术后屈光度、视力的比较，统计学的检验。结果术前97眼平均屈光度为＋2．16D、散光为-1．26D。术后97眼平均屈光度为＋1．01D，散光度为-0．81D。按胬肉侵入角膜内程度统计屈光状态发现，胬肉侵入角膜内越多对角膜屈光度的影响越大。结论翼状胬肉侵入角膜内越大对角膜屈光状态的影响越大，使患眼发生远视和散光。     

手术显微镜下翼状胬肉切除干细胞移植术前后散光的变化

目的观察翼状胬肉手术前后散光的变化，探讨胬肉切除时机和必要性。提出光学性翼状胬肉切除概念。方法翼状胬肉切除干细胞移植治疗翼状胬肉91例（98眼），手术前后检影，角膜曲率计检查，裂隙灯显微镜照相及角膜地形图检查，术后随访3～24个月。结果91眼均有不同程度的逆规性散光，平均（3．0±1．5）D，其程度与翼状胬肉侵入角膜的长度、厚度及形态有关。术后显著降低了角膜散光，平均（1．1±0．5）D（P〈0．001）。结论翼状胬肉生长和手术切除对角膜的屈光状态有显著影响。     

翼状胬肉角膜表面屈光状态分析

目的了解不同大小的翼状胬肉的角膜表面屈光状况方法对我科80只眼大小不同的翼状胬肉进行裂隙灯显微镜记录翼状胬肉横径（胬肉角膜缘与其顶端距离）、竖径（跨过角巩膜缘时的弧长）及面积（横径X竖径/2）,同时应用角膜地形图分析,记录simK（最徒径与最平径,散光值及轴向）、角膜中心屈光度、平均屈光度、以胬肉尖部为中心的扁平区内的最小屈光波（P-屈光波）、角膜散光并将上述数据进行统计分析。结果 70只眼单侧翼状胬肉长度和面积与散光呈正相关。10只眼双侧（鼻侧及颞侧长度〈4 mm）均生长胬肉的患者胬肉长度和面积与散光无相关性。但总屈光力较正常屈光力下降。结论翼状胬肉对角膜屈光有明显的影响,角膜地形图对此有很好的评估作用。     

翼状胬肉与角膜散光的关系初步报告

目的：探讨翼状胬肉与角膜散光的关系。方法：对50例（60只眼）翼状胬肉患者进行视力、屈光度、角膜曲率检查及翼状胬肉侵入角膜的长度测量,并对其散光度进行手术前后的对比观察。结果：60只眼均有程度不同的散光,有程度与翼状胬肉的侵入长度有关,术后随访2月,散光度下降。结论：翼状胬肉可引起角膜散光,以顺规散光为主,其程度与翼状胬肉侵入角膜长度有显著相关性,手术摘除翼状胬肉可改善膜散光,提高视力。     

翼状胬肉与角膜散光的观察

目的：研究翼状胬肉的生长与角膜屈光改变的关系。方法：对４５例翼状胬肉患者进行常规的视力、屈光度、角膜曲率检查以及胬肉侵入角膜的长度的测量,对３２只患眼进行手术前后屈光度的对比。结果：５０只患眼均存在不同程度的散光,且以顺规性散光为主,其程度与胬肉的大小有关。手术后一个月随访,其散光度数下降。结论;翼状胬肉可引起顺规散光,其程度与胬肉侵入角膜的大小有着显著相关性。胬肉手术可使角膜散光得以改善,提高视     

翼状胬肉大小与角膜散光的关系

目的:探讨翼状胬肉大小与角膜散光的关系。方法:选取64例70眼翼状胬肉患者纳入研究,测量裸眼视力、角膜曲率及胬肉侵入角膜缘长度,分析胬肉长度与角膜散光的相关度,对比翼状胬肉切除+角膜缘干细胞移植术手术前后裸眼视力。结果:术前69眼有不同程度的角膜散光,与胬肉侵入角膜长度相关,以循规性散光为主。术后1mo,其角膜散光明显下降,裸眼视力提高。结论:翼状胬肉可引起角膜循规性散光,散光程度与胬肉侵入角膜长度关系密切,手术可以使角膜散光改善、视力提高。     

翼状胬肉手术前后屈光变化

目的 回顾分析原发性翼状胬肉切除前后视力及眼屈光度的改变.方法 初发翼状胬肉23例(27眼),均行翼状胬肉切除联合自体球结膜移植,测量手术眼术前屈光度、角膜缘至胬肉顶点长度,术后角膜上皮完全愈合后测量眼屈光度,比较两次屈光度的差异及术前术后裸眼视力和最佳矫正视力的变化.结果 术前胬肉平均头部长度(3.11±0.87)mm,平均散光度(2.98±1.34)D,胬肉手术后平均散光度(1.00±0.52)D,术前术后视力及散光变化有统计学意义(P=0.0001).结论 翼状胬肉导致的眼球屈光不正以远视散光为主,手术治疗可以降低散光,提高视力.     

翼状胬肉手术时机的临床研究

目的　探讨翼状胬肉患者的手术时机。方法　对 4 0例 (6 2只眼 )翼状胬肉患者按胬肉侵入角膜的长度分为三组 : 组 (15只眼 ) <2 .5 mm , 组 (34只眼 ) 2 .5 mm～ 3.0 mm , 组 (13只眼 ) >3.0 mm。并对 6 2只眼行胬肉切除加角膜缘干细胞移植 ,对三组患者手术前后视力、散光度、角膜曲率的变化情况 ,及术后的复发情况进行对比观察。结果　术前散光 : 组患者为无散光或轻度散光 , 组患者为中度散光 , 组患者为重度散光 , 组患者散光度明显大于 组患者 , 、 组患者比较无明显差异 ;手术前后视力、散光度、角膜曲率变化 : 组无明显变化 , 、 组变化显著 (P <0 .0 1) ,即术后视力提高 ,散光度减轻 ,屈光力差减小 ;术后复发 : 组 1例复发 ,占 6 .6 7% ; 组 2例复发 ,占 5 .88% ; 组 5例复发 ,占 38.4 6 % ,且 3例患者因留下角膜薄翳而影响术后视力。结论　当翼状胬肉侵入角膜达 2 .5 5 m m～ 3.0 m m时 ,是胬肉手术的最佳时机     

不同翼状胬肉手术对角膜屈光影响的研究

目的 研究单纯翼状胬肉切除与翼状胬肉切除联合角膜缘干细胞移植两种手术术后角膜屈光的改变.方法 单侧翼状胬肉38例(54只眼),随机分为2组,行单纯翼状胬肉切除者16例(21只眼)为A组;行翼状胬肉切除联合角膜缘干细胞移植者22例(33只眼)为B组.两组均行术前及术后10d、1月的裸眼视力、角膜曲度和角膜散光的检测,进行对比分析.结果 A、B两组术后10d、1月的裸眼视力、角膜曲度和角膜散光与术前的差异有统计学意义.而两组相比,术后10d、术后1月的差异无统计学意义.结论 翼状胬肉手术可使角膜屈光改变.术后1月内,单纯翼状胬肉切除和翼状胬肉切除联合角膜缘干细胞移植对角膜屈光的影响相仿.     

翼状胬肉面积与角膜散光关系的分析研究

目的研究翼状胬肉面积(侵入角膜长度、角膜缘宽度、总面积)和角膜散光的关系。并探讨其引起角膜性散光的临界面积和翼状胬肉手术的时机及必要性。方法观察112单眼鼻侧翼状胬肉患者,分别测量出其侵入角膜长度、角膜缘宽度和总面积(总面积计算方法:翼状胬肉头部至半月皱襞的距离×角膜缘宽度/2)。角膜曲率计和OrbscanⅡ(3 mm区域)用以测量角膜散光。结果翼状胬肉侵入角膜长度0.38~5.69 mm,平均(2.15±1.12)mm,宽度1.35~8.26 mm,平均(3.27±1.20)mm;总面积(1.8~20.5)mm2,平均(6.6±4.1)mm2。翼状胬肉眼引起的角膜散光的平均值[(3.2±1.9)D]明显较对侧眼[(0.26±0.5)D]有显著意义(P<0.001)翼状胬肉引起角膜散光中顺规散光占59.2%,逆规散光占30.6%,斜轴散光占10.2%。翼状胬肉总面积与侵入角膜长度和角膜缘宽度呈正相关。不同翼状胬肉眼间侵入角膜长度越大,角膜缘宽度越宽,引起角膜散光越大(P<0.001)。翼状胬肉头部侵入角膜达(2.0±0.3)mm、宽度达(5.0±0.2)mm、总面积(6.25±1.9)mm2可以引起(2.5±0.9)D的角膜散光。结论翼状胬肉总面积(侵入角膜长度、角膜缘宽度、总面积)与角膜散光存在显著相关性。翼状胬肉头部侵入角膜达(2.0±0.3)mm、宽度达(5.0±0.2)mm、总面积(6.25±1.9)mm2可以考虑手术切除以使散光得以改善,从而提高患眼视力。     

Effects of pterygium on corneal spherical power and astigmatism

OBJECTIVE: To evaluate prospectively the corneal refractive status before and after pterygium surgery and its relationship with preoperative pterygium size. DESIGN: Prospective, nonrandomized, comparative (self-controlled) trial. PARTICIPANTS: One hundred thirty-six eyes undergoing primary pterygium removal surgery. MAIN OUTCOME MEASURES: Corneal spherical power, astigmatism, surface regularity index (SRI), and surface asymmetry index (SAI) before and after surgery, and the preoperative pterygium size. RESULTS: Before surgery, pterygium size significantly correlated with spherical power (Pearson's correlation coefficient, r = -0.370, P < 0.001), astigmatism (r = 0.600, P < 0.001), SRI (r = 0.367, P < 0.001), and SAI (r = 0.387, P < 0.001). The surgery significantly increased spherical power of the cornea, whereas astigmatism, SRI, and SAI were significantly decreased by the surgery (P < 0.01, paired t test with Bonferroni's correction of P value for multiple comparison). Surgically induced changes in spherical power (r = 0.598, P < 0.001) and astigmatism (r = 0.653, P < 0.001) significantly correlated with the preoperative pterygium size. Precise prediction of the magnitude of refractive changes based on the preoperative pterygium size was difficult. CONCLUSIONS: The presence of pterygium and its removal significantly influence the corneal refraction including spherical power, astigmatism, asymmetry, and irregularity, with the larger pterygium exerting the greater influence.     

Corneal topographic changes after four types of pterygium surgery

PURPOSE: To evaluate effects of different pterygium surgeries on corneal topography. METHODS: Pre- and postoperative computerized videokeratography was performed on 120 eyes of 115 patients undergoing pterygium removal. Four techniques were used: bare sclera, excision with mitomycin C, limbal-conjunctival autograft, and conjunctival autograft. Corneal spherical power, topographical astigmatism, pre- and postoperative topographic irregularity, and surgically induced astigmatism were compared among surgical approaches. RESULTS: Mean topographic astigmatism value decreased significantly 4 months postoperatively. The difference among the postoperative astigmatism values at 4 months was statistically significant (P < .001). Statistically significant differences were noted between the type of surgery and surgically induced astigmatism (P < .05), mean topographical astigmatism (P < .05), and spherical power (P < .05), but no significant difference was observed in topographic irregularity (P = .067). The amount of corneal steepening in each group was 0.06 +/- 0.5 for conjunctival autograft, 0.02 +/- 0.3 for limbal-conjunctival autograft, 2.34 +/- 1.1 for bare sclera, and 1.70 +/- 0.4 for mitomycin C. The mitomycin C group produced the most induced astigmatism and the limbal-conjunctival autograft group produced the least induced astigmatism. CONCLUSIONS: Although pterygium surgery significantly reduces refractive astigmatism and topographic irregularity, spherical power increases and the cornea becomes steeper. This steepening is apparent with the bare sclera or excision combined with mitomycin C approaches. Surgeons should consider the possibility of recurrence and the effects of different types of surgeries on topography.     

Quantitative analysis of regular and irregular astigmatism induced by pterygium.

PURPOSE: To quantitatively evaluate the influence of pterygium and its removal surgery on both regular and irregular corneal astigmatism. METHODS: In 19 eyes of 19 patients undergoing pterygium surgery, videokeratographic measurements were taken before and 1 month after surgery. Using Fourier harmonic analysis, dioptric data on mire rings were decomposed into spherical, regular astigmatism, and irregular astigmatism (decentration and higher order irregularity) components. The distance between the line of sight and the advancing edge of pterygium was measured, and the eyes were classified into two groups: large pterygium group (the distance <2.0 mm, n = 7) and small pterygium group (> or =2.0 mm, n = 12). Fifteen eyes of 15 subjects served as age-matched normal control eyes. RESULTS: Before surgery, the magnitudes of regular astigmatism and higher order irregular astigmatism showed significant correlation with the size of pterygium. Regular astigmatism, asymmetry, and higher order irregularity in the large pterygium group were significantly greater than those of normal control eyes. The pterygium removal surgery significantly improved these changes, but regular astigmatism and higher order irregularity in the large pterygium group still remained significantly greater than those in the normal control eyes. CONCLUSION: Pterygium induces a significant amount of regular and irregular astigmatism in proportion to its size. The removal surgery can improve these changes, but corneal distortion does not normalize completely in eyes with advanced pterygium.     

Effect of pterygium surgery on corneal topography

PURPOSE: To evaluate the effect of successful pterygium surgery on corneal topography. METHODS: Computerized corneal topography was performed on 20 eyes with pterygium before and 3 months after successful excision and limbo-conjunctival autograft surgery. Corneal shape, corneal spherical power, simulated keratometric astigmatism, surface regularity index (SRI), and surface asymmetry index (SAI) were assessed before and after surgery. Pre- and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and manifest refraction spherical equivalent (MRSE) were also evaluated. RESULTS: Changes in corneal shape were mainly a decrease in midline corneal flattening. Corneal spherical power was 41.65+/-3.29 diopters (D) (mean +/- SD) preoperatively and 44.58+/-1.55 D postoperatively (p=0.04). Simulated keratometric astigmatism was 5.47+/-3.45 D preoperatively and 1.79+/-1.52 D postoperatively (p=0.0005). SRI was 1.39+/-0.93 preoperatively and 1.10+/-0.57 postoperatively (p=0.03). SAI was 1.17+/-1.09 preoperatively and 0.75+/-0.73 postoperatively (p=0.02). UCVA was 0.31+/-0.33 preoperatively and 0.52+/-0.32 postoperatively (p=0.04). BSCVA was 0.73+/-0.20 preoperatively and 0.89+/-0.16 postoperatively (p=0.008). MRSE was -0.54+/-3.29 D preoperatively and -1.30+/-3.05 D postoperatively (p=0.45). CONCLUSIONS: Corneal topographic changes caused by the pterygium are almost reversible after surgical treatment. Successful pterygium surgery significantly reduces topographic astigmatism, SRI, SAI, and corneal flattening. However, precise prediction of these refractive changes is not always accurate.     

Impact of pterygium size on corneal topography and visual acuity - a prospective clinical cross-sectional study

PURPOSE: Pterygia may cause topographic changes featuring increase of astigmatism. The purpose of this study was to quantify the impact of the head-limbus-distance (=height) and limbal base length of the pterygium on the anterior corneal curvature and visual acuity before excision. PATIENTS AND METHODS: In 52 eyes (19 female, 33 male) with a mean age of 53 +/- 14 years the pterygium size (height, base length, area) was quantified using projected preoperative clinical slides and was correlated with visual acuity, refractive, keratometric, topographic astigmatism and Surface Regularity Index (SRI), Surface Asymmetry Index (SAI) of the TMS-1 videokeratoscope. RESULTS: The mean height of the pterygium was 3.1 +/- 1.4 (0.8 to 6.7) mm, the mean base length was 5.1 +/- 1.4 (2.9 to 7.8) mm, the estimated mean area was 11.4 +/- 6.9 (2.1 to 29.4) mm(2). The increasing pterygium height and area resulted in a highly significant elevation of the preoperative SRI and SAI values (p 相似文献   

Pterygium‐induced corneal astigmatism

A significant degree of corneal astigmatism can be induced by the encroachment of a pterygium onto a cornea. The pterygium generally causes with‐the‐rule corneal astigmatism that is hemimeridional on the side of the pterygium. There is a significant correlation between the extension of the pterygium onto the cornea and the amount of induced astigmatism. However, there is a poor correlation between pterygium‐induced astigmatism measured topographically and that measured by manifest refraction. Successful pterygium surgery will reduce pterygium‐induced refractive astigmatism and improve visual acuity. This paper outlines the management of a patient with an advanced pterygium, in whom a large degree of corneal astigmatism was induced by the encroachment of a pterygium onto the cornea. Subsequent excision of the pterygium brought about a reversal of the pterygium‐induced corneal astigmatism.     

Analysis of the pterygium size inducing marked refractive astigmatism

PURPOSE: Astigmatic changes induced by the pterygium and their relation to its size and morphology were analysed to establish the critical size for surgery before significant astigmatism occurs. MATERIALS AND METHODS: We evaluated the refraction in 148 eyes of 108 adult patients with primary pterygia. We grouped the astigmatic values according to the keratometric results correlating with the maximal length, width and the approximate total area of the pterigium encroaching on the corneal surface. RESULTS: Pterygia with length or width > or = 3.00 mm were related to significantly higher astigmatism than other groups (p<0.01). The effect of the pterygium morphology on corneal astigmatism was not significant. CONCLUSIONS: Pterygia exceeding 3.00 mm of length or width should be considered within the limits of surgery.     

Effect of pterygium surgery on corneal topography: a prospective study

OBJECTIVE: To evaluate the effect of pterygium surgery on the corneal topography and visual acuity and to correlate the results with patients' features. METHODS: A prospective, nonrandomized, self-controlled trial. Computerized videokeratography was performed in 54 patients (55 eyes) with primary pterygium before and after pterygium excision using bare sclera technique combined with intraoperative mitomycin C. The following topographic parameters were noted: corneal astigmatism at the central 3 mm; total mean refractive power of the whole cornea; surface regularity index (SRI); and surface asymmetry index (SAI). Best corrected visual acuity of the operated eyes was also examined. Differences between pre- and postoperative values were evaluated statistically with paired two-tailed t test and two-tailed Pearson correlation. RESULTS: The respective values (mean +/- SD) before and after treatment of the study parameters were as follows: simulated keratometric astigmatism at 3 mm, 3.12 +/- 2.43 and 2.51 +/- 2.50 (P = 0.05); mean SRI, 0.99 +/- 0.65 and 0.90 +/- 0.65 (NS); mean SAI, 1.37 +/- 1.69 and 1.23 +/- 1.49 (NS). Best corrected visual acuity was 20/40 preoperatively and 20/25 postoperatively (P < 0.01). Both pre- and postoperative astigmatism correlated with pterygium size. CONCLUSIONS: Pterygium surgery significantly reduces refractive astigmatism and improves SRI, SAI, and best corrected visual acuity.     

Analysis of pterygium size and induced corneal astigmatism

PURPOSE: To study the relationship between pterygium size (extension, width, total area) and corneal astigmatism in eyes with unilateral primary pterygium. Also to determine the critical size for surgery before the occurrence of a significant corneal astigmatism. METHODS: This study was conducted on 77 eyes of 77 patients with unilateral primary pterygium. The extension and width were measured and the total area was calculated. Automated keratometry was used to determine corneal astigmatism. RESULTS: Pterygium extension ranged from 0.25 to 6.50 mm (mean, 2.0 +/- 1.2 mm), width ranged from 1.50 to 10.0 mm (mean, 4.19 +/- 1.5 mm), and total area ranged from 0.3 to 24.3 mm(2) (mean, 5.0 +/- 4.8 mm(2)). The mean value of corneal astigmatism was significantly (P < 0.0001) higher in pterygium-affected eyes (1.2 +/- 0.9 D) than control eyes (0.6 +/- 0.5 D). With-the-rule was the main type of pterygium-induced astigmatism (49.4%), followed by against-the-rule (36.4%) and oblique (14.3%). Pterygium extension had the best correlation (Pearson correlation coefficient r = 0.462, P < 0.001), followed by total area (r = 0.447, P < 0.002) and width (r = 0.348, P < 0.002). A stronger correlation was noted between pterygium size and the difference in corneal astigmatism between pterygium-affected eyes and control eyes. Pterygium induced 2 D of corneal astigmatism when its extension exceeded 2.2 mm, width exceeded 5 mm, or total area exceeded 6.25 mm(2). CONCLUSIONS: Pterygium extension and total area have a stronger correlation with corneal astigmatism than does width. Surgical intervention is indicated when pterygium extension exceeded 2.2 mm, width exceeded 5 mm, or total area exceeded 6.25 mm(2).