Deep anterior lamellar keratoplasty by big-bubble technique for treatment corneal stromal opacities

PURPOSE: To evaluate the efficacy of using the big-bubble technique of deep anterior lamellar keratoplasty (DALK) for newer indications. DESIGN: Prospective, noncomparative, interventional case series. METHODS: Ten eyes of eight patients with pathologies involving the corneal stroma and sparing the Descemet membrane (DM) were included in this study conducted at a tertiary care hospital. The indications for DALK included corneal clouding attributable to mucopolysaccharidoses (n = 2), macular corneal dystrophy (n = 5), lattice corneal dystrophy (n = 1), granular corneal dystrophy (n = 1), and stromal scar attributable to infectious keratitis (n = 1). DALK was performed using the big-bubble technique in order to achieve the complete separation of DM from the corneal stromal tissue in the recipient's eye. Subsequently, the corneal stromal tissue was excised completely, and a full-thickness donor corneal lenticule without its DM was secured over the bared DM of the host. The main outcome measures of the study were the ability to successfully bare DM, the gain in visual acuity, and the presence of any complications. RESULTS: Using the big-bubble technique, DM was bared, and DALK could be performed successfully in all eyes. No intraoperative or postoperative complications were observed. All patients achieved a best-corrected visual acuity (BCVA) of 20/40 or better at the end of six months. CONCLUSIONS: DALK using the big-bubble technique can be useful in treating corneal stromal dystrophies, corneal clouding attributable to mucopolysaccharidoses, and stromal scar attributable to infectious keratitis.     

Femtosecond laser-assisted lamellar keratoplasty (FSLK) for anterior corneal stromal diseases

Our objective was to study the outcome of femtosecond-assisted lamellar keratoplasty (FSLK) in stromal corneal diseases. This is a retrospective chart review of 17 patients (20 eyes) who underwent FSLK for anterior corneal pathologies. Main outcome measures were refractive results following FSLK, complications, and graft survival. Mean follow-up time was 42 ± 15 (7–58) months. Preoperative best spectacle-corrected visual acuity (BSCVA) was ≤20/40 in 17 eyes. Postoperative BSCVA ≥ 20/40 was achieved in 12/14 at 12 months, 11/12 at 24 months, and 10/12 eyes at 36 months; postoperative BSCVA ≥ 20/25 was achieved in 8/14, 8/12, and 5/12 eyes at 12, 24, and 36 months, respectively. One eye had vertical gas break through the epithelium during the FSLK. One eye had postoperative epithelial rejection and two eyes had stromal rejection treated successfully with topical steroids. Another eye had epithelial ingrowth that was not progressive; however, the same eye developed bacterial keratitis and scarred graft 32 months post-FSLK. One eye had graft dehiscence and one eye developed excessive interface fibrosis. Five out of 20 grafts failed due to the recurrence of the original disease (3), corneal scarring (1), and excessive interface fibrosis (1). FSLK provides many advantages over conventional PK and DALK, with faster visual rehabilitation and emmetropization of the manifest refraction rather than inducing ametropia and irregular astigmatism.     

Femtosecond laser-assisted deep anterior lamellar keratoplasty for keratoconus and keratectasia

AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty (DALK) for keratoconus and post-LASIKkeratectasia.METHODS:In this non-comparative case series, 10 eyes of 9 patients underwent DALK procedures with a femtosecond laser (Carl Zeiss Meditec AG, Jena, Germany). Of the 9 patients, 7 had keratoconus and 2 had post-LASIK keratectasia. A 500 kHz VisuMax femtosecond laser was used to perform corneal cuts on both donor and recipient corneas.The outcome measures were the uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), corneal thickness, astigmatism, endothelial density count (EDC), and corneal power.RESULTS: All eyes were successfully treated. Early postoperative evaluation showed a clear graft in all cases. Intraoperative complications included one case of a small Descemet’s membrane perforation. Postoperatively, there was one case of stromal rejection, one of loosened sutures, and one of wound dehiscence. A normal corneal pattern topography and transparency were restored, UCVA and BCVA improved significantly, and astigmatism improved slightly. There was no statistically significant decrease in EDC.CONCLUSION: Our early results indicate that femtosecond laser-assisted deep anterior lamellar keratoplasty could improve UCVA and BCVA in patients with anterior corneal pathology. This approach shows promise as a safe and effective surgical choice in the treatment of keratoconus and post-LASIK keratectasia.     

飞秒激光辅助的深板层角膜移植术治疗角膜基质病变

目的评价飞秒激光辅助的深板层角膜移植术（DALK）治疗角膜基质病变的早期临床效果及安全性。方法系列病例研究。13例（14眼）各种角膜基质病变患者（外伤后角膜瘢痕1眼,角膜炎后角膜瘢痕8眼,角膜基质层营养不良5眼）采用飞秒激光辅助的DALK术进行治疗。评价指标包括手术前后裸眼视力、最佳矫正视力、内皮细胞密度和并发症。结果所有手术均顺利完成,术中无任何并发症。平均随访时间（7．3±3．8）个月（2—14个月）。与术前相比,有11眼裸眼视力提高（78．6％）,平均提高1．7行（未变～6行）;所有患者最佳矫正视力均较术前提高,平均提高2．4行（1—8行）。有3眼采用治疗性准分子激光消融术进行辅助治疗,最后一次随访时统计,内皮细胞密度丢失率为1％,未见植片排斥、感染、上皮植入等并发症。结论飞秒激光辅助的DALK术可提高各种角膜基质病变患者的裸眼视力及最佳矫正视力,飞秒激光可透过混浊的角膜进行基质深层的有效光滑的切割。     

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.     

Phacoemulsification in eyes with corneal opacities after deep anterior lamellar keratoplasty

To evaluate the maneuverability and efficacy of phacoemulsification and intraocular lens (IOL) implantation in eyes with corneal opacities after deep anterior lamellar keratoplasty (DALK), twelve eyes of 12 patients with mild to moderate corneal opacities after DALK and coexisting cataracts were analyzed retrospectively. Phacoemulsification and IOL implantation assisted with anterior capsule staining, as well as non-invasive optical fiber illumination, were performed on all eyes. No intraoperative or postoperative complications were noted. Mean corrected distance visual acuity (logMAR) improved from 1.24±0.17 to 0.73±0.22. Post-phaco intraocular pressure was maintained between 13 to 20 mm Hg in all cases throughout the follow-up period. Mean endothelial cell density decreased from 2258.42±205.94 to 1906.25±174.23 cells/mm2. Phacoemulsification and IOL implantation are safe and valid in eyes with mild to moderate corneal opacities after DALK and coexisting cataracts when assisted with anterior capsule staining and non-invasive optical fiber illumination.     

应用准分子激光原位角膜磨镶术矫治穿透性角膜移植术后高度屈光不正

目的 探讨应用准分子激光原位角膜磨镶术（laser in situ keratomileusis,LASIK)矫治穿透性角膜移植术（penetrating keratoplasty,PKP)后高度屈光不正的疗效。方法 应用LASIK技术治疗PKP术后高度屈光不正患者10例（10只眼）。结果 术后随访期间,全部角膜植片保持透明,无排斥反应发生;平均等效球镜值由术前的－11．85D降至术后的－3．38D,差异有显著性（P＜0．05）;平均散光度由6．75D降至2．70D,差异有显著性（P＜0．05）,矫正最大散光度为10．00D;平均裸眼视力由0．1提高至0．8,最佳者达1．5;平均最佳矫正视力由0．8提高至1．1。结论 LASIK技术是矫治PKP术后高度屈光不正安全、有效的方法;角膜屈光手术技术的不断发展和完善,可为解决PKP术后高度屈光不正问题带来希望。     

Penetrating keratoplasty for corneal ectasia after laser in situ keratomileusis

PURPOSE: To improve the visual acuity of patients with progressive keratectasia following laser in situ keratomileusis (LASIK). METHODS: Five eyes of four patients underwent penetrating keratoplasty for ectasia after LASIK: In one patient the second eye was operated on 10 months after the first keratoplasty. The pre- and postoperative refraction, best spectacle-corrected visual acuity, and topographic data were evaluated. RESULTS: The preoperative refraction was -20.0 diopters (D) with high cylindrical values in all eyes at the time of surgery. After penetrating keratoplasty, mean spherical equivalent was -13.08+/-3.62 (SD) and mean refractive cylinder was -3.87+/-1.12 (SD). In one eye Urrets-Zavalia syndrome was noted as an early postoperative complication. In the second operated eye of another patient, there had been graft rejection several times. In this patient, frequent steroid use led to secondary glaucoma and he required filtering surgery. CONCLUSIONS: Penetrating keratoplasty is effective and successful in treating iatrogenic keratectasia after LASIK, but these patients need a close and lifelong follow-up to treat lateterm complications such as graft rejection and secondary glaucoma.     

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。     

LASIK术中微型角膜板层刀对角膜厚度的影响

目的　比较 L ASIK手术前后角膜厚度的变化 ,分析微型角膜板层刀对角膜厚度的影响。方法　 48例(96只眼 )的角膜厚度在 L ASIK术前及术后不同时期进行测量 ,比较术后理论值与实测值的差异 ,分析理论值与实测值的差异所在 ,从而判断微型角膜板层刀是否对角膜厚度产生一定的影响。结果　术后 3天、7天的角膜厚度实测值与理论值有显著性差异 (P <0 .0 5 ) ,术后 1月实测值与理论值差异无显著性 (P >0 .0 5 )。结论　 L ASIK术中微型角膜板层刀的切割作用对角膜厚度会产生一定的影响。     

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.     

飞秒激光辅助的大气泡法深板层角膜移植治疗圆锥角膜

目的评价飞秒激光辅助的大气泡法深板层角膜移植术治疗圆锥角膜临床效果及安全性。方法系列病例研究。9例（11眼）圆锥角膜患者采用飞秒激光辅助进行大气泡法深板层角膜移植手术。供体及受体角膜均采用500 kHz VisuMax飞秒激光进行垂直边切,术前超声测量角膜最薄点厚度,角膜厚度为（359.7±49.8）μm,术前UCVA为指数～0.1,术前BCVA为指数～0.12,供体直径为（7.51±0.14）mm,受体直径为（7.38±0.10）mm,随访时间为（7.70±2.88）个月。结果所有患者手术顺利,术中无并发症,术后早期所有角膜植片透明。角膜厚度为（481.4±51.3）μm,角膜地形图恢复正常形态。术后最后1次随访,UCVA为0.15～0.40,BCVA为 0.30～0.80。结论飞秒激光辅助的大气泡法深板层角膜移植对于圆锥角膜患者具有良好的临床效果及安全性。     

Deep anterior lamellar keratoplasty in post-laser in situ keratomileusis keratectasia

We describe a technique using deep anterior lamellar keratoplasty (DALK) in 5 eyes that developed keratectasia after LASIK. The technique is based on surgical manipulation that allows visualization of the lamellar dissection depth using a posterior approach to reach the predescemetic space. The mirror effect, indentation effect, and folding effect were used to determine proximity to Descemet's membrane. The same diameter donor and recipient buttons were used to correct myopia. The donor button without Descemet's membrane was placed using 10-0 nylon sutures. No intraoperative or postoperative complications occurred. The mean best spectacle-corrected visual acuity changed from 0.16 diopter (D) +/- 0.05 (SD) (range 0.10 to 0.25 D) before DALK to 0.68 +/- 0.19 D (range 0.5 to 1.0 D) after DALK. Deep anterior lamellar keratoplasty may be a better alternative than penetrating keratoplasty for any pathology with healthy endothelium.     

穿透性角膜移植治疗LASIK术后继发圆锥角膜

目的 观察穿透性角膜移植治疗准分子激光原位角膜磨削术(Laserin situkeratomileusis,LASIK)术后继发圆锥角膜的效果.方法 对6例LASIK术后确诊为继发圆锥角膜的患者进行穿透性角膜移植术,选用直径7～7.5mm植片,与植床等大.术后随访1～5年,观察和评价其疗效.结果 本研究6例患者LASIK术前角膜厚度平均为394.9μm.术后圆锥发生时间(13±3.4)个月,穿透性角膜移植术后,中央角膜厚度平均为504.7μm,视力明显增进,随访期内未见圆锥角膜复发.讨论我们建议,进行LASIK对术中切削时,角膜基质床的厚度不应小于270μm,角膜总厚度不应小于400μm.对LASIK术后继发圆锥角膜患者行穿透性角膜移植术,植床直径与角膜植片等大,术后再选择性拆除缝线,将有助于降低术后免疫排斥反应发生率和圆锥复发,减少手术源性散光,提高视力.