深板层角膜移植术治疗急性期圆锥角膜的探讨

目的 观察深板层角膜移植术治疗急性期圆锥角膜的手术时机及临床效果.方法 总结自2008年9月至2009年9月于邢台眼科医院住院的急性期圆锥角膜患者8例,均于发病后2～3周采用深板层角膜移植术治疗,术后随访观察6～12个月,观察角膜植片的透明度及视力情况.结果 8例患者中,术前裸眼视力4例为手动,4例为眼前指数,矫正均不提高;术后裸眼视力为0.2～0.5的6例,≥0.6的2例,术中发现后弹力层裂孔呈裂隙状;术后6例大部分裂孔已愈合,角膜植片透明;2例裂孔较大者(尚有约1mm未愈合)术后第3天发现少许层间积液,植片基质层轻度水肿,经前房补气及包扎后层间积液吸收,角膜植片恢复透明;全组病例后弹力层破裂处无明显混浊.结论 深板层角膜移植术治疗急性期圆锥角膜可以取得较好的临床效果.     

Deep anterior lamellar keratoplasty for keratoconus

PURPOSE: To investigate surgical outcomes after deep anterior lamellar keratoplasty (DALKP) in eyes with keratoconus. METHODS: Retrospective review of 127 eyes of 118 keratoconus patients who underwent DALKP at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia between January 1, 1998 and November 30, 2001. The mean age of all patients was 25.9 years (range 11-70 years). The mean follow-up for all patients was 10.9 months (range 4-61 months). Baring of Descemet's membrane (DM) during DALKP was achieved in 47 (37%) eyes; some stroma was left during operation in the remaining 80 (63%) eyes. Snellen visual acuity, intraoperative complications, and postoperative graft status were assessed. RESULTS: At the last follow-up visit, 74% of all eyes were able to achieve a best-corrected visual acuity of 20/50 or better. This level of improvement was more statistically significant with baring of DM (P = 0.005). Intraoperative perforation of DM occurred in 16 (13%) cases and was statistically significant in eyes with deep corneal scars (P = 0.012). However, this perforation did not seem to have an impact on the final visual acuity (P = 0.48). Main graft-related complications included graft-host vascularization (7/127), stromal graft rejection (4/127), graft infection (1/127), and persistent epithelial defect (1/127). CONCLUSIONS: Deep lamellar keratoplasty provides a safer and successful alternative to penetrating keratoplasty for keratoconus patients but remains a challenging procedure. Endothelial graft rejection is absent after DALKP. However, stromal graft rejection, although very rare, does occur.     

Deep lamellar keratoplasty in keratoconus with healed hydrops

PURPOSE: To report a case of successful deep lamellar keratoplasty (DLK) in a patient with keratonous after healed hydrops. METHODS: A 17-year-old boy underwent DLK for corneal scar secondary to healed hydrops in a case of keratoconus. RESULTS: The graft was clear, with a postoperative best spectacle-corrected visual acuity of 20/20. CONCLUSIONS: DLK may be a viable option in healed hydrops.     

Deep anterior lamellar keratoplasty in the management of keratoconus

Advanced cases of keratoconus often require surgical intervention to restore corneal anatomy and improve eyesight. Penetrating keratoplasty (PK) although commonly performed has potential risk of immunological rejection and is now no longer automatically the first choice of surgery. DALK procedures have evolved, which allows surgical replacement of recipient''s corneal stroma, leaving behind healthy descemet membrane (DM) and endothelium. This reduces the risk of allograft endothelial rejection and late graft failure. In recent times, DALK techniques have led to significant improvements in visual outcome and current results are comparable to PK. Big bubble technique of DALK has become the most popular among the various surgical techniques described. Manual near DM DALK also gives good outcome although the visual recovery is often delayed. Future integration of femtosecond laser technology along with diagnostic imaging technology is likely to further improve outcomes of DALK in keratoconus.     

Deep lamellar keratoplasty with lyophilised tissue in the management of keratoconus

AIMS: Data are presented on the use of deep lamellar keratoplasty (DLK) using lyophilised donor corneal tissue, in the management of patients with keratoconus (KC). METHOD: The results of DLK on 44 eyes (42 patients) are reported. The mean patient age was 29.8 years (range 10-56). Mean follow up was 25 months (range 6-100). In seven patients with mental handicap or severe mental illness, the collection of acuity and refractive data was limited. RESULTS: Perforation of Descemet's membrane (DM) occurred in nine cases (20%). A double anterior chamber formed in five cases, which resolved spontaneously in three patients. Persistent epithelial defects occurred in two cases, one of which necessitated replacement of the graft. The median postoperative uncorrected visual acuity was 6/36. The median corrected postoperative acuity was 6/9. Those with more than 1 year of follow up (n=25) had a significantly better acuity (p=0.015). This group achieved 6/12 or better in 80% (n=20) and 6/6 or better in 40% (n=10). The mean postoperative spherical error was +0.28 (SD 3.49) dioptres (D). The mean refractive cylinder was 3.85 (1.87) D. CONCLUSION: This detailed retrospective study of DLK for the treatment of patients with KC, with an average follow up of 2 years, highlights the advantages and disadvantages of this technique.     

On-lay lamellar keratoplasty for the treatment of keratoconus.

On-lay lamellar keratoplasty was performed in 29 patients who had keratoconus. Twelve patients (greater than 1 year follow-up) showed an average decrease in keratometry of 9.13 +/- 2.02 (mean +/- SE) D; 6 patients (6-11 months follow-up) showed an average of 10.15 +/- 2.88 D. Visual acuity continued to improve for about one year after surgery. Six patients with best visual acuities of 20/20 before surgery showed an average visual acuity of 20/29 +/- 11 (mean +/- SD) 4 months after surgery; 4 with more than a year of follow-up achieved an average of 20/26 +/- 9. Four patients with 20/40 preoperatively achieved an average of 20/63 +/- 33 four months after surgery; 3 with more than a year of follow-up showed an average of 20/38 +/- 13. All patients with successful grafts can now tolerate contact lenses for daily wear.     

甘油冷冻保存角膜深板层角膜移植术治疗圆锥角膜

目的分析甘油冷冻保存角膜深板层角膜移植术（DALK）治疗圆锥角膜术后角膜内皮细胞密度及屈光状态变化。方法回顾性病例研究。分析圆锥角膜患者用甘油冷冻保存的角膜材料行DALK治疗的44例（49眼）病例资料,其中17例（17眼）患者于术后1个月、1年、2年、3年、4年按期进行随访,且随访资料完整。分析术后角膜内皮细胞丢失率、视力以及屈光状态。结果患者平均随访时间为（39．0±12．6）个月,无一例发生植片免疫排斥。术前平均内皮细胞密度（ECD）为（2597±578）个／mmz．术后1个月、1年、2年、3年、4年时平均ECD为（1790±409）cells／mm2、（1703±443）cells／mm2,（1632±389）cells／mm2、（1638±357）cells／mm2、（1675±283）cells／mm2、（1611±421）cells／mm2。术后4年ECD较术前减少34．2％。术前平均裸眼视力（UCVA）为（1．40±0．60）logMAR,平均最佳矫正视力（BCVA）（0．98±0．54）logMAR,术后1个月、1年、2年、3年、4年平均BCVA分别为（0．44±0．12）logMAR、（0．36±0．20）logMAR、（0．32±0．23）logMAR、（0．29±0．20）logMAR、（0．27±0．16）logMAR。结论使用甘油冷冻保存的角膜材料的角膜移植术治疗圆锥角膜可获得较好的视力,角膜内皮细胞丢失率低．远期疗效较好。     

Penetrating keratoplasty versus deep anterior lamellar keratoplasty for the treatment of keratoconus

Purpose To compare the outcome of penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK) in the surgical management of keratoconus (KC). Patient and methods A retrospective review was conducted of the medical records of all patients treated with PKP or DALK for KC at University of Iowa Hospitals and Clinics from January 1, 2000, to December 31, 2006. The main outcome measures were visual outcome, graft survival, and complications. Cases with a minimum follow-up of 6 months were included in the statistical analysis. Results Of 41 eyes that met the inclusion criteria, 30 eyes were treated with PKP and 11 eyes were treated with DALK. The mean follow-up was almost identical for eyes treated with PKP or DALK (21.9 vs. 22.5 months, respectively). At the most recent examination, the mean best spectacle-corrected visual acuity (BSCVA) was 20/28 for the PKP group and 20/29 for the DALK group (P = 0.77). The percentage of eyes that achieved BSCVA of 20/25 or better was higher in the PKP group than in the DALK group (77.3 vs. 45.5%, respectively), but this difference was not statistically significant (P = 0.72). Endothelial rejection occurred in 4 (13.3%) eyes after PKP. Visually significant interface haze occurred in the early postoperative course in 2 (18.2%) eyes after DALK. No cases of late-onset endothelial failure were found in either group. Conclusion Treatment of KC with PKP or DALK is associated with similar visual outcomes, graft survival, and prevalence of sight-threatening complications.     

Deep lamellar keratoplasty (DLKP) in keratoconus patients using viscoadaptive viscoelastics

PURPOSE: To demonstrate the effectiveness and safety of using viscoadaptive viscoelastics in deep lamellar keratoplasty (DLKP) for keratoconus. METHODS: A nonrandomized, comparative, interventional case series was performed on 12 eyes of 10 consecutive keratoconus patients without a history of acute hydrops. Patients were treated with DLKP using ophthalmic viscosurgical devices (OVDs) to dissociate Descemet membrane (DM) from the stroma before suturing of the donor cornea. Eight eyes were operated using Viscoat (dispersive), and 4 eyes were operated using Healon V (viscoadaptive). RESULTS: Six out of 8 eyes in the Viscoat group were successfully treated, and 2 eyes were converted to PKP because of tears in the DM. Another 3 eyes had double chambers as a result of perforations or tears in DM, which were treated by injecting air into the anterior chamber. All 4 eyes in the Healon V group were successfully operated, with 1 case with microperforation of DM during suturing. Healon V offered better control of the area to be dissociated and served as a pseudostroma that protects the exposed DM while the overlying stroma is maneuvered. CONCLUSION: Healon V is a valuable tool for performing DLKP in difficult cases such as keratoconus.     

Deep lamellar keratoplasty

INTRODUCTION: Deep lamellar keratoplasty (DLKP) is a surgical technique in which the entire corneal stroma is removed down to the Descemet membrane. METHODS: The difference between deep lamellar keratoplasty and classic lamellar keratoplasty is qualitative rather than quantitative. In the first technique, the anatomical cleavage plane provides clear separation of the stroma and the Descemet membrane. This plane has a clear and smooth surface. On the contrary, classic lamellar dissection down to 2/3 of the stroma results in a very rough and uneven surface with a risk of low visual acuity. PURPOSE: To compare the results of 200 cases treated with deep lamellar keratoplasty and 200 cases of penetrating keratoplasty (PK). RESULTS: No rejection episodes were recorded in the 200 patients who underwent DLKP surgery, whereas rejection occurred in 4% of the patients after PK. The number of endothelial cells, measured with a Konan instrument 1 month after removal of the sutures in patients who underwent deep lamellar keratoplasty, was double that in patients who underwent penetrating keratoplasty. CONCLUSION: The number of endothelial cells does not change after DLKP, but is substantially reduced after PK. The degree of astigmatism is greatly reduced and functional recovery is faster with the first technique. These are the main reasons why we think that DLKP could replace PK as the best procedure in all cases in which no endothelial damage is involved.     

深板层角膜移植术治疗圆锥角膜疗效观察

目的:评价深板层角膜移植治疗圆锥角膜的效果。方法:采用深板层角膜移植术治疗132例140眼圆锥角膜,对其疗效进行观察分析。术后随访6～48mo。结果:术后矫正视力0.2～0.4者13例14眼,～0.8者92例96眼,>0.8者27例30眼,发生排斥反应5眼,植片透明131例139眼,半透明1例1眼,8眼出现后弹力层皱褶。结论:深板层角膜移植术具有并发症少,能减少内皮型排斥反应的发生,术后视力好,且对供体材料要求较低等优点,为治疗圆锥角膜提供了安全有效的选择。     

飞秒激光辅助深板层角膜移植术治疗圆锥角膜的临床观察

目的 观察飞秒激光辅助完成深板层角膜移植术治疗圆锥角膜的临床效果.方法 对5例（5眼）圆锥角膜患者施行飞秒激光辅助完成的深板层角膜移植术进行随访观察.术后6个月后观察其最佳矫正视力,角膜最薄点厚度,中央区角膜内皮细胞密度的变化情况.结果 术后视力均有明显提高,角膜最薄点的厚度较术前明显增加,中央区角膜内皮细胞的密度变化不大.结论 飞秒激光可以有效帮助深板层角膜移植术的实施.