Ho：YAG激光角膜热成形术对兔眼组织的生物效应

本文使用波长为２．１μｍ的Ｈｏ：ＹＡＧ激光对兔眼周边部角膜行激光角膜热成形术（Ｌａｓｅｒｔｈｅｒｍｏｋｅｒａｔｏｐｌａｓｙ，即ＬＴＫ），采用不同激光能量和脉冲数通过裂隙灯显微镜、光镜以及扫描、透射电镜观察术后不同时间兔角膜的生物学反应特征，证实ＬＴＫ术为安全、有效的术式，以７８Ｊ／ｃｍ２能量密度、２个脉冲、１０Ｈｚ频率，光凝角膜深度可达角膜厚度７７％。     

Ho：YAG激光角膜热成形术

激光角膜热成形术是近年来研究的热门课题之一。Ｈｏ：ＹＡＧ激光由于其穿透深度与角膜厚度相当，因而成为激光角膜热成形术研究的主要工具。初期的临床研究结果表明这种手术方式对矫正低度和中度远视及散光是有效的，而且术后无明显的并发症。本复习有关献，就Ｈｏ：ＹＡＧ激光角膜热成形术的发展简史、作用机理及初期临床研究结果进行综述。     

激光角膜热成形术的临床观察

目的探讨Ho：YAG激光角膜热成形术（LTK）治疗远视的临床效果。方法对12例14只轻、中度远视眼行LTK术，术前屈光度为＋0．50～＋5．00D，能量密度44J／cm2，平均随访7．6±1．2月。结果LTK术对轻度远视（≤＋3．00D）有效，对ECCE术后远视（≤＋3．00D）有效，但术后均有不同程度的屈光回退。结论LTK术具有方法简单、迅速、见效快以及无短期并发症等优点，不失为有前途的手术治疗。     

传导式角膜成形术和激光角膜热成形术治疗远视的研究进展

随着近视治疗的日臻成熟 ,远视越来越成为屈光手术医师关注的热点。新近发展起来的激光角膜热成形术(laserthermalkeratoplasty ,LTK)及传导式角膜成形术 (conduc tivekeratoplasty ,CK)作用于周边角膜 ,不损伤中央视区 ,能较好矫治中低度远视 ,本研究从发展史、机制、手术过程、临床结果、并发症等方面将其综述如下。     

钬激光角膜热成形术的疗效分析

目的:评价钬激光角膜热成形术(LTK)治疗轻度远视的疗效、安全性和并发症。方法:我们的研究对年龄>45岁的患者12例18只轻度远视眼行Ho:YAG激光LTK术治疗,能量密度65J/cm~2,平均随访2a。结果:患者年龄45～65(平均55.25±10.12)岁,术前屈光度+0.50～+2.25(平均+1.30±0.58)D,术前裸眼视力0.44±0.23,术后屈光度得以全部矫正,术后1mo,没有屈光回退,术后3mo,4眼屈光回退+0.25D。术后6mo,剩余屈光度在±0.50D和±1.00D以内的百分率分别为83%,89%,已矫屈光度和预矫屈光度符合率较好。之后存在屈光回退趋势,2a后屈光回退减缓。最佳视力出现在术后2wk内,以后裸眼视力开始回退。术前裸眼视力>1.0者为0,术后1mo,裸眼视力均较术前有非常显著的提高。术后3mo,裸眼视力达1.0者14眼(78%)。术后2a,裸眼视力达1.0者10眼(56%)。结论:Ho:YAG激光LTK术对轻度远视有效。临床观察证实此手术方法简单、安全,见效快以及并发症少等优点,为治疗轻度远视的手术方方法之一,但尚需长期观察其屈光稳定性。     

传导性角膜成形术治疗中低度远视的临床研究

目的 评价传导性角膜成形术治疗中低度远视眼的安全性、有效性和可预测性。方法 对43例（67眼）中低度远视眼患者采用传导性角膜成形术进行治疗,根据患者远视度数的不同在周边角膜6mm到8mm区域进行8～32点的射频治疗。记录并比较术前及术后1个月、3个月、6个月及1年的屈光度,远近视力,角膜屈光力,眼内压,角膜内皮计数的变化。结果 术后1年裸眼远视力有42眼（62.7%）≥1.0,54眼（80.6%）≥0.8,63眼（94.1%）≥0.5,裸眼近视力有22眼（32.9%）≥J5,41眼（61.2%）≥J6,64眼（95.5%）≥J7,最佳矫正视力与术前比较无变化。术后1年等效球镜屈光度为（0.70±0.48）D比术前下降68.9%。ORBSCAN-II裂隙光扫描角膜地形图测量测的中央区3.0mm角膜平均屈光力术后1年（45.70±1.13）D,5.0mm角膜平均屈光力术后1年（44.76±1.53）D,与术前比较均有显著性差异,术后各时间点屈光力均值方差分析有显著性差异,两两比较经SNK检验6个月和术后1年屈光力无差异,角膜形态于术后6个月已趋于稳定,眼内压与角膜内皮细胞计数手术前后比较均无显著性差异。结论 传导性角膜成形术治疗中低度远视患者是一种安全,有效的方法,但术后6个月内易发生回退,其手术量表尚需进一步改进。     

角膜热成形术的研究进展

角膜热成形术作为治疗圆锥角膜和远视的手术方法经历了悠久的发展历程，早在100^＋a前就用于动物实验，近30^＋a来，随着对热源研究的进展，角膜热成形术逐渐应用于临床。目前，一种以射频能量为热源的传导性角膜成形术被正式应用于临床治疗远视、散光、老视，并取得了较好的疗效，综述如下。     

CO2激光角膜热成形术的实验研究

用低功率CO2激光在兔眼做角膜热成形术籍以了解凝固点数目及中央视区大小与远视矫正效果的关系。结果显示CO2激光角膜热成形术在照射5mm视区时，能矫正低度远视。当视区小至一定程度时，仅使角膜中央扁平，而非变凸，且可引起不规则散光。病理观察发现热凝点呈换形，深达角膜的2／3，楔形区内胶原增生，相互交织成张力收缩，半年后渐呈平行规则排列，与远视矫正效果渐下降是一致的。     

准分子激光原位角膜磨镶术和钬激光热角膜成形术治疗原发性远视眼

目的　评价准分子激光原位角膜磨镶术 (LASIK)和钬激光热角膜成形术 (LTK)治疗原发性远视眼的有效性、预测性和安全性。方法　对 3 0例原发性远视眼患者 ( 1 0 0～ 8 5 0 0D) ,分别采用LASIK( 19眼 )和LTK( 11眼 )进行治疗 ,术后平均随访 12个月。结果　至术后 12个月时 ,LASIK组裸眼视力达到 0 5～ 0 9和 1 0以上者分别为 42 1%和47 4% ;LIK组裸眼视力达到 0 5～ 0 9和 1 0以上者分别为 2 7 3 %和 45 5 %。LASIK组屈光度在≤± 0 5D和 >± 0 5～± 1 0D者分别为 5 2 6%和 3 1 6% ;LIK组屈光度在≤± 0 5D和 >± 0 5～± 1 0D者分别为 45 5 %和 2 7 3 %。结论　LASIK可有效地治疗低中度远视眼且具有较好的预测性和安全性 ;LTK治疗低度远视眼简便、安全 ,但术后有屈光回退。对手术技术和激光治疗的不断改进将进一步提高预测性和稳定性。     

LASIK治疗远视眼的初步结果分析

目的　为了评价激光原位角膜磨镶术(excimerlaserinsitukeratomileusis,LASIK)治疗远视眼的有效性、预测性和安全性。方法　对19例原发性远视眼患者( 1.00～ 8.50D),采用LASIK进行治疗,术后平均随访6mo(3～9mo)。结果　至术后6mo时,平均残余屈光度为 0.22D±0.79D,84.2%的患者屈光度在±1.0D以内,89.5%的患者裸眼视力达到0.5以上。结论　LASIK可有效地治疗 1.00～ 6.00D的远视眼且具有较好的预测性和安全性。对手术技术和激光治疗程序的不断改进将有助于进一步提高手术的预测性和稳定性。     

Holmium YAG laser sclerostomy ab externo for refractory glaucoma

Ab externo thermal sclerostomy was performed with the holmium YAG (thulium, holmium, chromium-doped YAG crystal) laser in 21 eyes of 20 patients with refractory glaucoma. We used either the 5-fluorouracil (5-FU) or mitomycin C (MMC) antimetabolites in all cases. The rate of intraocular pressure (IOP) control defined as IOP < 21 mmHg regardless of whether antiglaucoma medication was applied postoperatively) was estimated by the life-table methods of Kaplan-Meier. The postoperative IOP control rate was 47.1% in the MMC-treated group at 57 months, and 14.3% in the 5-FU-treated group at 52 months. There were statistically significant differences in success rates between the MMC- and 5-FU-treated groups. We observed no clinically significant complications except excess filtration associated with a shallow anterior chamber in one case. This procedure is thought to have several advantages over more conventional filtration surgery; the operation time is shorter, and there is no need for intraocular manipulation, which means conjunctival trauma is minimal. However, the IOP control rate was substantially lower than that achieved via conventional trabeculectomy. Our results suggest that the selection of patients and the use of MMC is an important factor in maintaining successful filtration.     

Holmium laser thermokeratoplasty for the reversal of hyperopia after myopic photorefractive keratectomy

BACKGROUND—Overcorrection following myopic photorefractive keratectomy, with a target of emmetropia, leaving a spherical equivalent of more than 1.0 D of hyperopia is of the order of 1%. This study analyses the efficacy, safety, and 1 year stability of outcome of laser thermokeratoplasty (LTK) carried out on eyes with persistent symptomatic hyperopia following photorefractive keratectomy (PRK) for myopia.
METHOD—11 consecutive eyes in 11 patients underwent LTK using the Technomed Holmium 25, contact holmium:YAG laser system. The mean spherical equivalent before LTK was +2.06 D (SD 1.02 D, range +1.00 D to +4.75 D) based on a non-cycloplegic refraction. Between four and 16 burns were used per eye, depending on the error to be corrected.
RESULTS—The mean spherical equivalent was +0.511 D (SD 0.551) at 1 year. Ten of the 11 eyes were seeing 6/12 or greater, unaided (91%) and nine were within 1.0 D of the target sphere equivalent (82%). Recovery of unaided acuity occurred during the first week in four cases and the first month in the rest. One eye lost greater than one line of best corrected vision (9%), going from 6/5 to 6/7.5 and one gained a line (9%), 6/12 to 6/7.5. No complications occurred during the follow up period.
CONCLUSIONS—In this study of a small number of eyes with hyperopia induced by PRK, LTK appears safe, predictable, and stable for low errors followed for 1 year.

     

准分子激光原位角膜磨镶术治疗远视的临床观察

目的:观察和评价用准分子激光原位角膜磨镶术(laserin situ keratomileusis,LASIK)治疗远视的安全性、有效性和稳定性。方法:应用德国鹰视蓝调酷眼准分子激光治疗仪机远视治疗程序治疗远视及合并散光的患者18例33眼。术后观察视力、屈光度及阅读舒适性改变,所有患者均随访6~12mo。结果:至术后3mo时,平均残余屈光度为+0.22±0.79D,91%的患者屈光度在±1.0D以内,97%患者裸眼视力达到0.5以上。术后所有患者感觉阅读舒适,阅读时间超过1h无头痛、眼胀等不适。结论:LASIK手术治疗远视是一种安全有效且稳定性好的方法。     

Nd:YAG激光治疗后发性白内障的临床观察

目的:探讨Nd:YAG激光治疗后发性白内障的临床效果。方法:后发性白内障患者203例224眼,经详细眼科检查,散瞳后,采用国产Nd:YAG激光(波长1064μm)进行激光治疗,激光瞄准光聚焦于后囊膜表面,环形切开后囊膜,切开直径约3～4mm。激光后定期复查。对治疗前后视力,采用SPSS11.0统计软件进行统计分析比较。结果:本组患者均为一次性激光切开成功,成功率为100%;视力均获提高,经统计学处理,治疗前后视力有显著性差异(P<0.01)。结论:Nd:YAG激光是治疗后发性白内障安全有效的方法。