Comparison of deep lamellar endothelial keratoplasty and penetrating keratoplasty in patients with Fuchs endothelial dystrophy

PURPOSE: To evaluate and compare 1-year postoperative visual acuity, refractive results, endothelial cell density (ECD), and complications in a consecutive group of patients who underwent deep lamellar endothelial keratoplasty (DLEK) with those who underwent penetrating keratoplasty (PK) performed by 1 surgeon. METHODS: We prospectively analyzed results of 20 consecutive patients with Fuchs dystrophy and pseudophakia who underwent small-incision DLEK surgery and retrospectively compared these results with those of 23 consecutive patients with Fuchs dystrophy and pseudophakia who underwent standard PK surgery during the same period. Main outcome measurements were best spectacle-corrected visual acuity (BSCVA); refractive, keratometric, and topographic astigmatism; topographic irregular astigmatism; absolute change in spherical equivalent; and ECD. Postoperative complications in the 2 groups were also analyzed. RESULTS: Preoperative BSCVA was significantly better in the DLEK group than the PK group (P = 0.013). Postoperative BSCVA was significantly better in the DLEK group than the PK group at 6 months (P = 0.025) and similar in each group at 12 months. Twelve-month postoperative refractive, keratometric, and topographic astigmatism was significantly less in the DLEK group than the PK group (P < 0.001). Surface asymmetry index and change in keratometric spherical equivalent was significantly less in the DLEK group than the PK group at 12 months postoperatively (P < 0.001). Preoperative ECD was significantly higher in the DLEK group (3072 +/- 307 cells/mm) than the PK group (2779 +/- 413 cells/mm). Twelve-month postoperative ECD was similar in the DLEK group (1293 +/- 469 cells/mm) compared with the PK group (1303 +/- 454 cells/mm; P = 0.949, not significant). Twelve-month percent endothelial cell loss was higher than reported in previous studies but was similar in the DLEK group (57.9%) compared with the PK group (53.1%). Twelve months postoperatively, all grafts were clear in the DLEK and PK groups. CONCLUSIONS: DLEK surgery resulted in more rapid vision recovery, significantly less regular and irregular astigmatism, and less change in spherical equivalent than PK surgery. Endothelial cell loss was significant in both groups but was not significantly different in the DLEK group from the PK group. DLEK surgery has significant advantages over PK surgery, but long-term ECD and graft survival in DLEK surgery should be studied.     

Endothelial keratoplasty using donor tissue not suitable for full-thickness penetrating keratoplasty

PURPOSE: To evaluate the use of corneal donor tissue deemed unsuitable for full-thickness penetrating keratoplasty (PK) for use in deep lamellar endothelial keratoplasty (DLEK) and to compare postoperative results to those of DLEK surgery using donor tissue that is suitable for PK. METHODS: Small-incision DLEK surgery was performed using 39 donor corneas unsuitable for PK. Thirty-five donors had anterior scars or opacities, 3 donors had pterygia within the 8-mm zone, and 1 had prior LASIK. All donor preparation was completed by manual stromal dissection. The DLEK surgical and postoperative courses were reviewed. Preoperative and 6-month postoperative results of this study group were compared with a control group consisting of the first 55 consecutive small-incision DLEK patients receiving donor corneas that had no criteria excluding them from use in PK. Four eyes in the study group and 1 eye in the control group had the confounding variables of the presence of an anterior-chamber lens or surgical vitrectomy with macular disease in the recipient eye. RESULTS: There was no significant difference in preoperative measurements of best spectacle-corrected visual acuity (BSCVA; P = 0.372), donor endothelial cell density (ECD; P = 0.749), or corneal topography [surface regularity index (SRI), P = 0.485; or surface asymmetry index (SAI), P = 0.154] between the 2 groups. For the patients receiving corneas deemed unacceptable for PK, at 6 months after surgery, the vision (P = 0.002) and corneal topography measurements improved significantly from before surgery (SRI, P < 0.001; SAI, P < 0.001), and there was no significant change in refractive astigmatism (P = 0.240). There was a significant difference in the vision at 6 months postoperatively between the overall study group and the control group, with the mean vision of the study group at 20/56 and the control group at 20/43 (P = 0.015). If eyes with known cystoid macular edema (CME) and vitrectomy are removed from each group, there is no significant difference in vision at 6 months between the study group and the control group (P = 0.110), with the average BSCVA of those receiving donor corneas unsuitable for PK equal to 20/48 (range, 20/25-20/200) and the average vision for those receiving PK-acceptable donor tissue equal to 20/43 (range, 20/20-20/80). The 6-month average refractive astigmatism of the study group was 1.12 +/- 0.99 D (range, 0.00-4.00 D), and the average endothelial cell count was 2064 +/- 396 cells/mm(2) (range, 1208-2957 cells/mm(2)). There was no significant difference in 6-month postoperative endothelial cell count (P = 0.443), refractive astigmatism (P = 0.567), or corneal topography (SRI, P = 0.332; SAI, P = 0.110) in study patients who received corneas unsuitable for PK compared with control patients who received corneas suitable for PK. CONCLUSIONS: Endothelial keratoplasty such as DLEK surgery with manual donor preparation broadens the donor pool by enabling corneas that cannot be used for PK to be used for selective endothelial transplantation without deleterious postoperative results.     

Rapid visual rehabilitation after endothelial transplants with deep lamellar endothelial keratoplasty (DLEK)

OBJECTIVE: To evaluate the speed of visual recovery in 30 consecutive patients with Fuchs endothelial dystrophy who received deep lamellar endothelial keratoplasty (DLEK) transplant surgery. METHODS: Best spectacle-corrected visual acuity (BSCVA) by manifest refraction and uncorrected visual acuity (UVA) were prospectively measured at preop, at 1 week, and at 1, 3, 6, 12, and 18 months after DLEK. The LogMAR of the postop vision was compared against each patient's preop vision. Visual results at 6 months were also compared against potential acuity meter (PAM) results in 27 patients. All eyes had reached at least the 6-month follow-up interval. RESULTS: Two of the first 32 eyes originally enrolled in the protocol were converted at surgery to standard penetrating keratoplasty (PK), and so DLEK data were obtained on 30 eyes for this report. Average BSCVA and UVA were better than preop vision at every time point, achieving statistical significance by 3 months (P < 0.05). Average preop BSCVA was 20/162 (range 20/40 to CF), improving to 20/63 at 3 months (range 20/25 to 20/200), 20/56 at 6 months, 20/51 at 1 year, and 20/46 at 18 months. Of the 27 patients who had PAM testing, 52% (14 of 27) had BSCVAs within 1 line of their PAM at 3 months, 63% (17 of 27) were within 1 line at 6 months, 71% (12 of 17) were within 1 line at 1 year, and 83% (10 of 12) were within 1 line at 18 months (P < 0.05 compared with preop from 3 months on). CONCLUSION: DLEK surgery preserves the normal corneal surface topography and allows rapid visual recovery of useful vision by 3 months. The visual acuity continues to improve over time.     

Outcomes of femtosecond laser-assisted Descemet membrane endothelial keratoplasty for failed penetrating keratoplasty

ObjectiveTo analyze the outcomes of femtosecond laser-enabled Descemet membrane endothelial keratoplasty (FE-DMEK) in treatment of failed penetrating keratoplasty (PK) grafts.Study DesignRetrospective, interventional case series.ParticipantsPatients with a failed PK graft who underwent FE-DMEK at Toronto Western Hospital, Canada, between 2014 and 2016.MethodsOutcome measures were best spectacle-corrected visual acuity (BSCVA), endothelial cell density (ECD), rates of graft detachment, rebubbling, rejection, and failure.ResultsEight eyes of 8 patients were included. Mean age was 64.7 ± 14.5 years. Average follow-up time was 27.5 ± 8.6 months (range 15–36 months). There were no intraoperative complications and no issues with the creation of the descemetorhexis—all descemetorhexis cuts were complete. There were no significant graft detachments and no need for rebubbling. There were no primary or secondary graft failures and all grafts were viable at the final follow-up. BSCVA worsened from 0.41 ± 0.33 logMAR (Snellen equivalent ∼20/50) to 1.37 ± 0.91 logMAR (Snellen equivalent ∼20/460) after PK failure (p = 0.012), and improved significantly after FE-DMEK to 0.34 ± 0.14 logMAR (Snellen equivalent ∼20/45), 0.42 ± 0.12 logMAR (Snellen equivalent ∼20/50), 0.27 ± 0.14 logMAR (Snellen equivalent ∼20/35), and 0.25 ± 0.16 logMAR (Snellen equivalent ∼20/35) at 6 months, 12 months, 24 months, and at final follow-up, respectively (p = 0.013, p = 0.027, p = 0.022, and p = 0.008, respectively). ECD decreased from 2837 ± 229 cells/mm² preoperatively to 1069 ± 413 cells/mm² (61.4% cell-loss rate) and 974 ± 344 cells/mm² (64.8% cell-loss rate) at 12 months and 24 months, respectively (p < 0.001). Cell loss was higher than in historical controls.ConclusionsFE-DMEK was effective in the management of PK graft failure, showing very low detachment and rebubble rates.     

Descemet’s stripping automated endothelial keratoplasty and penetrating keratoplasty for Fuchs’ endothelial dystrophy

Purpose: To compare the outcome of Descemet’s stripping endothelial keratoplasty (DSAEK) to that of penetrating keratoplasty (PK) in patients with Fuchs’ endothelial dystrophy. Methods: The first 20 patients who underwent DSAEK at the Department of Ophthalmology, Aarhus University Hospital were compared to 20 patients treated with classic PK. Best‐corrected visual acuity, subjective spectacle refraction and corneal thickness were registered before surgery and 1, 3, 6 and 12 months after DSAEK surgery; they were also measured before surgery and 12 months and 2–3 years after PK. Endothelial cell density was measured 12 months after surgery in both groups. Results: Two primary graft failures were observed in the DSAEK group; no failures were seen in the PK group. Best spectacle‐corrected visual acuity (BSCVA) at 12 months after surgery was significantly better in the DSAEK group (0.56 ± 0.04) than in the PK group (0.33 ± 0.06). At this time, 70% of the DSAEK‐treated eyes but only 25% of PK‐treated eyes had obtained a BSCVA of 0.5 or better. Two to three years after surgery, BSCVA was 0.5 or better in 55% of PK‐treated eyes. Refractive ametropia and astigmatism were significantly smaller in DSAEK‐treated eyes than in PK‐treated eyes, even after suture removal and arcuate keratotomy. Endothelial cell density (cells/mm²) after 1 year was lower in DSAEK‐treated (1.338 ± 113) than in PK‐treated eyes (1.610 ± 124), but the difference was not statistically significant. Conclusion: DSAEK seems to be superior to PK in treating Fuchs’ endothelial keratoplasty, although primary graft failure may be more common. Visual recovery is faster, and major ametropia and astigmatism is not induced. Long‐term follow‐up studies are essential to assess whether this conclusion also holds true more than 1 year after surgery.     

In pursuit of emmetropia: spherical equivalent refraction results with deep lamellar endothelial keratoplasty (DLEK)

PURPOSE: To determine if the new technique for endothelial transplantation of DLEK (deep lamellar endothelial keratoplasty) can offer predictable corneal curvature and improved refractive spherical equivalent results compared with reports for traditional penetrating keratoplasty. METHODS: Twenty-seven consecutive Fuchs corneal dystrophy patients received DLEK surgery to replace their endothelium. Topographic corneal curvature and refractive spherical equivalents were evaluated at preop and at 6 and 12 months postop. RESULTS: At 6 months (n = 27) the average corneal curvature was 43.8 +/- 1.4 D, representing a mean change from preop corneal curvature of only -0.1 +/- 1.7 D. At 12 months (n = 18) the average corneal power was 43.5 +/- 1.7 D. The average corneal curvature at 6 and 12 months was not significantly different from pre-op (P = 0.119). The average refractive spherical equivalent result at 6 months was -0.44 +/- 1.7 D, and at 12 months was -0.44 +/- 1.6 D. The 6- and 12-month refractive spherical equivalent results were not statistically different from the preop spherical equivalent refractions (P = 0.922). All patients could be easily refracted, and several patients were fit with stable glasses as early as 3 months after DLEK surgery. CONCLUSION: DLEK surgery preserves the preoperative corneal curvature and therefore allows better matching of postop corneal curvature to the IOL power. This increase in predictability of the postoperative corneal curvature makes the choice of IOL power for the new "triple procedure" more accurate, eliminates the need for contact lens wear after PK, and provides earlier visual rehabilitation after endothelial replacement.     

Objective measurement of backscattered light from the anterior and posterior cornea in vivo

PURPOSE: To develop an objective and repeatable method of measuring corneal backscattered light from different depths of the cornea in vivo. METHODS: A modified slit lamp ("scatterometer"), with a video camera and synchronous white strobe light, was used to capture images of a 0.1-mm-wide slit beam through the cornea. Image analysis software was developed to measure backscatter from digitized high-magnification images of 82 normal corneas of 41 subjects. Forty eyes of 20 of the same subjects were examined again after 1 month. Mean backscatter from the anterior, middle, and posterior thirds of the cornea was compared between repeated measurements, and expressed in arbitrary scatter units (SU). RESULTS: Backscatter in the anterior third of the cornea was 451 +/- 42 SU (mean +/- SD, n = 82), from the middle third was 274 +/- 29 SU (n = 82), and from the posterior third was 242 +/- 28 SU (n = 82). The difference in backscatter measured a month apart was 5 +/- 27 SU (P = 0.34), 2 +/- 17 SU (P = 0.42), and 0 +/- 15 SU (P = 0.95) in the anterior, middle, and posterior thirds of the cornea, respectively. Minimum detectable differences between measurements were 12, 8, and 7 SU in the anterior, middle and posterior thirds, respectively (alpha = 0.05, beta = 0.20, n = 40). CONCLUSIONS: Backscatter can be measured at different depths of the cornea from high-magnification digitized images of a narrow slit beam through the cornea. The method is objective and repeatable and can be applied in prospective studies of deep and posterior lamellar keratoplasty.     

深板层角膜内皮移植治疗大泡性角膜病变

目的 探讨严重且复杂的大泡性角膜病变行无缝线深板层角膜内皮移植术(DLEK)的可行性、并发症及处理措施.方法 采用非随机回顾性连续病例研究.2005年10月至2006年3月在中山大学中山眼科中心对15例(15只眼)严重且复杂的大泡性角膜病变行无缝线DLEK联合前段玻璃体切除术(2例联合睫状体沟缝线固定人工晶状体植入术,2例联合人工晶状体摘出术,1例联合人工晶状体置换术).术后4～6个月,4例无晶状体眼行睫状体沟缝线固定人工晶状体植入术.术后复查视力、角膜散光、角膜曲率及内皮细胞密度,用眼前段光学相干断层成像(OCT)检查深板层内皮植片的愈合情况.采用重复测量的方差分析检验时间点之间的差异.结果 术后13例植片与植床贴附良好;1例植片移位,经重新复位后贴附良好;1例层间积液,5 d后吸收.随访期内,所有植片均透明.5例(33.3%)植片与植床边缘间有约0.5～1.0 mm宽的裂隙,其中2例(13.3%)在裂隙处上皮面出现小水泡,分别于术后2周和3个月后消失.术后4例(26.7%)裸眼视力为0.4,3例(20.0%)裸眼视力为0.3,4例(26.7%)裸眼视力为0.2,1例(6.7%)裸眼视力为0.1.术后6、9及12个月,角膜散光度数分别为(2.80±0.70)D、(2.60±0.70)D及(2.20±0.60)D(F=5.591,P=0.090);角膜曲率分别为(43.60±1.90)D、(44.10±1.30)D及(44.10±1.00)D(F=1.515,P=0.237);术前、术后6、9及12个月,角膜厚度分别为(666.1±70.6) μm、(544.5±30.9)μm、(538.2±34.7)μm及(532.4±41.6)μm(F=32.692,P=0.000).术后内皮细胞密度为(1915.7±90.8)个/mm2.结论 严重且复杂的大泡性角膜病变行无缝线DLEK是安全、有效的,但通常需联合其他的眼前段手术.DLEK术后4～6个月,无缝线的植片可耐受其他的眼前段手术.(中华眼科杂志,2008,44:726-733)     

Cost-effectiveness of Descemet stripping automated endothelial keratoplasty versus penetrating keratoplasty in patients with endothelial dysfunction in India

Purpose:The aim of this study was to compare the cost-effectiveness and perform cost-utility analysis of Descemet stripping automated endothelial keratoplasty (DSAEK) vs. penetrating keratoplasty (PK) in Indian population.Methods:This was an institutional, ambispective, observational study. Patients who underwent PK or DSAEK for endothelial dysfunction were included and followed up for 2 years; those with other ocular comorbidities were excluded. The analysis was performed from the patient’s perspective receiving subsidized treatment at a tertiary care hospital. Detailed history, ophthalmic examination, total expenditure by patient, and clinical outcomes were recorded. The main outcome measures were best spectacle-corrected visual acuity (BSCVA), graft survival (Kaplan–Meier survival estimates), incremental cost-effectiveness ratio (ICER), and incremental cost-utility ratio (ICUR). Utility values were based on quality-adjusted life years (QALYs) associated with visual acuity outcomes. Statistical analysis was performed using SPSS software package, version 12.1; a value of P < 0.05 was considered statistically significant.Results:A total of 120 patients (PK: 60, DSAEK: 60) were included. At 2 years, for a similar logMAR BSCVA, [PK (0.32 ± 0.02), DSAEK (0.25 ± 0.02); P = 0.078], the overall cost for PK (13511.1 ± 803.3 INR) was significantly more than DSAEK (11092.9 ± 492.1 INR) (difference = 1952.6 INR; P = 0.01). ICER of DSAEK relative to PK was –39,052 INR for improvement in 1 logMAR unit BSCVA. ICUR of DSAEK relative to PK was –1,95,260 INR for improvement in 1 QALY.Conclusion:DSAEK was more cost-effective than PK in patients with endothelial dysfunction at 2 years.     

Implantation of verisyse phakic intraocular lens to correct myopic refractive error after penetrating keratoplasty in pseudophakic eyes

PURPOSE: We report 2 cases in which a Verisyse phakic intraocular lens (PIOL) was used to successfully treat high myopia after penetrating keratoplasty (PK) in pseudophakic patients. METHODS: Case 1 involved a 69-year-old pseudophakic man with a manifest refraction (MR) of -6.50 + 1.75 x 048 and a best spectacle corrected visual acuity (BSCVA) of 20/40 approximately 16 months after PK in the right eye. Case 2 was a 78-year-old pseudophakic man who had an MR of -9.00 + 5.75 x 132 with a BSCVA of 20/100 approximately 24 months after PK in the left eye. RESULTS: In case 1, 10 months after Verisyse PIOL implantation, the MR was pl +2.00 x 135 with a BSCVA of 20/30. Endothelial cell density (ECD) in this patient decreased from 1926.1 to 815.3 cells/mm over 17 months. In case 2, 24 months after Verisyse PIOL implantation, the MR was -3.25 + 3.50 x 105 with a BSCVA of 20/60. ECD in this patient decreased from 2108.4 to 753.8 cells/mm in 30 months. CONCLUSION: The Verisyse PIOL may provide an alternative method to correct high myopia for anisometropia in pseudophakic patients after PK. In this report, PIOL implantation was associated with a decrease in ECD. Further studies are required to determine the long-term effects and ultimate safety of PIOL placement on the integrity of the cornea endothelium after corneal transplant in pseudophakic patients.     

Small-incision deep lamellar endothelial keratoplasty (DLEK): six-month results in the first prospective clinical study

PURPOSE: To evaluate the visual, topographic, and endothelial survival results in 25 consecutive patients who have received small-incision deep lamellar endothelial keratoplasty (DLEK) transplant surgery. METHODS: DLEK surgery was performed in 25 patients with Fuchs endothelial dystrophy or pseudophakic bullous keratopathy utilizing a 5-mm scleral access incision. Snellen visual acuities, refractive astigmatism, endothelial cell counts, and corneal topography were prospectively measured at preop and at 6 months after small-incision DLEK endothelial replacement surgery. RESULTS: Best spectacle-corrected visual acuity improved from an average of 20/90 (range 20/25 to 2'/200) before surgery to an average of 20/44 (range 20/25 to 20/200, P < 0.001) 6 months after surgery, with 56% of patients 20/40 or better at 6 months. Average refractive astigmatism at 6 months was 1.31 +/- 0.59 diopters (range 0.25 to 2.50 diopters), representing an average increase in astigmatism of 0.45 diopters from preop. Despite folding of the donor graft for placement into the recipient posterior lamellar bed, the average postoperative endothelial cell count at 6 months was 2122 +/- 510 cells/mm2 (range 1097 to 3202 cells/mm2) or an average 24% cell loss from donor eye preop measurements, a level of cell loss comparable to that reported after PK or after large-incision DLEK surgery. CONCLUSION: Small-incision DLEK surgery preserves the recipient corneal topography, resulting in very little change in astigmatism from preop. The excellent postoperative donor endothelial cell counts attest to the survival of donor endothelium despite folding of the graft for insertion. The small-incision DLEK technique may become the standard for endothelial replacement surgery in the future.     

Descemet-stripping automated endothelial keratoplasty

PURPOSE: To evaluate the speed of visual recovery in 16 consecutive patients with corneal endothelial dysfunction who received Descemet-stripping automated endothelial keratoplasty (DSAEK). METHODS: This is a retrospective study of a novel method for small-incision endothelial transplantation (DSAEK). Endothelial replacement was accomplished with Descemet stripping of the recipient and insertion of a posterior donor tissue that had been prepared with a microkeratome. Best spectacle-corrected visual acuity (BSCVA) by manifest refraction, endothelial counts, and dislocation rates were measured up to 12 months after DSAEK. RESULTS: Sixteen consecutive patients underwent uncomplicated DSAEK. Three patients had known optic nerve or macular disease precluding vision better than 20/200. Of the remaining 14 patients, 11 had BSCVA of 20/40 by postoperative week 12 (7 by week 6). The remaining 2 were 20/50 by weeks 6 and 12. All 14 patients were 20/40 or better at 1 year. One patient had a primary graft failure, and surgery was repeated with 20/40 BSCVA at 1 year. The dislocation rate was 25%. The average cell count between 7 and 10 months was 1714. The average pachymetry was 682. CONCLUSION: DSAEK surgery allows rapid, excellent BSCVA visual recovery. The rate of visual recovery is more rapid than usually found with penetrating keratoplasty.     

Short-term results of penetrating keratoplasty performed with the Femtec femtosecond laser

PURPOSE: To evaluate the use of the Femtec femtosecond (fs) laser for penetrating keratoplasty (PK) in the treatment of corneal diseases. DESIGN: Prospective, nonrandomized clinical study. METHODS: Nine eyes of nine patients underwent surgery for PK. Five had pseudophakic bullous keratopathy, three had Fuchs dystrophy, and one presented in a keratoconus patient. A Femtec (20/10 PerfectVision; GmbH, Heidelberg, Germany) fs laser was used to create penetrating cuts on donor and recipient corneas. All patients were evaluated for uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), pachymetry, topography, and endothelial cell density (ECD). Scanning electron microscopy (SEM) was performed on corneal tissue after surgery. RESULTS: All eyes were treated successfully without intraoperative complications. The mean follow-up was 6 +/- 3 months. At the last postoperative examination mean BSCVA was 20/69 and there was a significant improvement (P = .08) in both UCVA and BSCVA. Mean astigmatism was 2.9 +/- 1.2 diopters. Mean ECD was 1194 +/- 465 cells/mm(2) with a mean cell loss after surgery of 49.8% +/- 19.8%. SEM displayed smooth rectilinear cut margins and minor remaining tissue bridges. One patient presented a retinal detachment three months after surgery that was successfully treated and two subjects showed an allograft rejection. CONCLUSION: Use of the Femtec fs laser was effective and safe to perform PK. Short-term visual results and refractive results are analogous to conventional PK or other fs laser-assisted PK studies. Longer-term follow-up of additional cases is necessary to precisely quantify the endothelial cell loss after fs surgery.     

Videokeratography in conductive keratoplasty

PURPOSE: We used EyeSys videokeratography to evaluate corneal shape changes induced by conductive keratoplasty, a procedure that utilizes radio frequency energy to alter corneal shape to correct hyperopia. METHODS: Follow-up data were available for 19 eyes (out of 24 eyes of 13 patients). Preoperative spherical hyperopia ranged from +0.75 to +3.25 D with astigmatism <0.75 D. Manifest refractive spherical equivalent refraction (MRSE), uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical parameter predicted corneal acuity (PCA), corneal uniformity index (CU Index), regular astigmatism, total astigmatism, average simulated keratometry (Avg Sim K), effective refractive power, and asphericity were measured preoperatively and at 6 and 12 months postoperatively. RESULTS: Twelve months postoperatively, mean PCA, CU Index, and BSCVA were maintained at preoperative levels. Mean UCVA (LogMAR) improved from 0.53+/-0.21 to 0.10+/-0.19 (P<.05) with a mean MRSE change from +1.62+/-0.76 D to -0.06+/-0.84 D (P<.05) from preoperative to 12 months postoperative. Mean asphericity increased +0.044+/-0.24 D (P>.05), mean Avg Sim K increased 1.88+/-0.72 D (P<.05), mean effective refractive power increased 1.71+/-0.79 D (P<.05), mean cylinder (cycloplegic refraction) increased 0.19+/-0.36 D (P<.05), mean regular astigmatism increased 0.25+/-0.49 D (P>.05), and mean irregular astigmatism decreased 0.01+/-0.13 D (P>.05) from preoperative to 12 months after conductive keratoplasty. CONCLUSIONS: Avg Sim K and effective refractive power changes support the refractive results; 12-month postoperative maintenance of BSCVA, PCA, and CU Index suggest the procedure is safe. Conductive keratoplasty induced a slight regular astigmatism in some eyes, which decreased with time. The increase in mean corneal asphericity indicated possible induction of central and peripheral cornea changes.     

角膜后弹力层剥除内皮移植术治疗大泡性角膜病变的初步疗效观察

目的 探讨角膜后弹力层剥除内皮移植手术的适应证、手术方法以及对大泡性角膜病变的疗效与并发症的处理.方法 非随机回顾性系列病例研究.选择2006年9月至2007年10月于中山大学中山眼科中心住院的8例(8只眼)大泡性角膜病变患者行角膜后弹力层剥除内皮移植术.术中剥除患眼角膜中央部直径7.75 mm的后弹力层和病变的内皮层,再将植床周边部基质表面刮粗糙,然后按常规角膜内皮移植术的方法植入内皮植片.术后观察植片与植床贴合和植片移位等情况.随访3～9个月,记录患者视力、植片透明度、角膜散光及内皮细胞密度.结果 8例患者术后植片与植床贴合良好,未出现植片移位.术后第1天,1例患者出现继发性闭角型青光眼,术后48 h后缓解.8例患者术后植片透明,术前存在眼痛的6例患者术后眼痛缓解.8例患者术后视力均提高,最好矫正视力为0.3～0.7,平均角膜散光度数为(1.90±0.70)D,平均内皮细胞密度为(2014±192)个/mm2.结论 与深板层角膜内皮移植术比较,角膜后弹力层剥除内皮移植术的操作较简单,对受体角膜和前房的创伤更小.术中将植床周边部基质表面刮粗糙,可有效预防术后植片移位.     

Long-term topical steroid treatment improves graft survival following normal-risk penetrating keratoplasty

PURPOSE: To assess the impact of duration of topical steroid treatment on the incidence of endothelial graft rejection after normal-risk penetrating keratoplasty (PK). DESIGN: Prospective, institutional, longitudinal, randomized interventional trial including 406 eyes (age 52 +/- 19 years; follow-up 42 +/- 18 months). METHODS: Postoperative treatment started with prednisolone acetate 1% eye drops five times daily and was tapered over the first six months. Patients were then randomized into either short-term (stop topical steroid treatment) or long-term treatment (continue steroids once daily for 12 months). RESULTS: During follow-up, 29 eyes (7.1%) developed an episode of endothelial graft rejection. Graft rejections were significantly more common in the short-term (19 of 202; 9.1%) compared with the long-term treatment group (10 of 204: 4.9%; P = .001). CONCLUSIONS: Long-term, low-dose topical steroid treatment protects against immunologic graft rejections.     

Initial results of small incision deep lamellar endothelial keratoplasty (DLEK)

PURPOSE: To evaluate the results of replacing the posterior stroma and endothelium, using small incision deep lamellar endothelial keratoplasty (DLEK) surgical technique, in patients with corneal endothelial dysfunction. DESIGN: Noncomparative case series. METHODS: Fifteen eyes of 15 patients (six males and nine females) with endothelial dysfunction were included in this study. Through a 5-mm scleral incision, a deep lamellar pocket was created across the cornea, followed by excision of an 8.0-mm disk of posterior lamellar corneal tissue. Same size lamellar donor disk was prepared and placed in position without the need of suture fixation. Best spectacle-corrected visual acuity (BSCVA), refraction, endothelial cell density, corneal topography, and corneal thickness were analyzed. RESULTS: Average BSCVA preoperative was 20/200 (range 20/40 to hand movements (HM)), improving to 20/50 (range 20/20 to 20/120) at a mean follow-up of 7.2 months. Average refractive astigmatism at last follow-up was 1.46+/-1.21 diopters (range, 0 to 4 diopters). Preoperative average donor endothelial cell density was 2047+/-311 cells/mm2, and that at last follow-up was 1732+/-514 cells/mm2. Preoperative average pachymetry was 801.4+/-211.3 microm, improving to 553+/-90.4 microm at last follow-up. CONCLUSIONS: Initial results with small incision DLEK procedure indicate that it is a safe procedure that provides healthy donor endothelial cell count and function postoperatively, with encouraging visual results.     

Lamellar keratoplasty - new concepts

New concepts of lamellar keratoplasty techniques mainly deal with the refinement of the so-called deep lamellar endothelial keratoplasty (DLEK). The aim of the deep lamellar technique is to expose bare Descemet's membrane of the recipient and to suture in a full thickness graft. Graft rejections are not known with DLEK. We describe the preparation techniques of Anwar, Melles, and Krumeich and discuss the advantages and disadvantages. The femtosecond laser enables the surgeon to cut the cornea non-mechanically with a cutting accuracy of +/- 10 microns. Fuchs endothelial dystrophy can be treated by posterior lamellar keratoplasty (POLK). In this technique only a sheet of Descemet's and endothelium are replaced. In severe alkali burn with limbal stem cell deficiency a lamellar corneo-scleral disc can be grafted in order to restore the limbus. Routine central penetrating keratoplasty should follow at least half a year later.     

Deep lamellar endothelial keratoplasty: surgery in complex cases with severe preoperative visual loss

PURPOSE: This study was designed to report the use of deep lamellar endothelial keratoplasty (DLEK) in combination with other intraocular surgeries in the treatment of eyes with severe bullous keratopathy and visual loss. METHODS: DLEK surgery was performed in six patients with severe bullous keratopathy and preoperative vision with a range of between count fingers and light perception only. DLEK was combined with vitrectomy and placement of a ciliary sulcus sutured intraocular lens in four patients and with cataract surgery in one patient. Two patients with vitreoretinal disease underwent pars plana vitrectomy within only 4 months after the DLEK donor tissue had been placed. Graft clarity, Snellen visual acuities, refractive astigmatism, endothelial cell counts, and corneal topography were prospectively measured at 6 and 12 months postoperatively. RESULTS: At 6 months after DLEK surgery, all grafts were clear and vision improved in all patients. Best spectacle-corrected visual acuity improved from count fingers level (or worse) before surgery to a range of 20/40 to 20/200 after surgery. Average refractive astigmatism at 6 months was 2.0 diopters (range, 0.50-4.00 diopters). The average postoperative endothelial cell count was 1,679 +/- 380 (range, 1,200-2,298) cells/mm at 6 months and 1,449 +/- 365 (range, 1,105-2,043) cells/mm at 12 months. Vitreoretinal surgery subsequent to graft placement did not affect corneal clarity or dislodge the grafted tissue. CONCLUSIONS: DLEK surgery can be used in cases with severe visual loss caused by bullous keratopathy with transfer of healthy donor endothelium, clearing of the central cornea, and restoration of useful vision. DLEK also can be successfully combined with other intraocular surgeries such as vitrectomy, intraocular lens exchange, and sutured intraocular lens surgery. The DLEK graft can tolerate subsequent intraocular surgery performed as early as 3 months after placement of the donor tissue.     

深板层角膜内皮层移植治疗角膜内皮损伤的实验研究

目的:探讨深板层角膜内皮层移植在兔角膜内皮损伤模型的应用效果。方法:选择新西兰白兔24只,制作兔角膜内皮损伤模型第2d随机分为两组:实验组进行深板层角膜内皮层移植术组,对照组不予处理。分别于术后1,2,3,7,14d;1mo观察眼压、前房反应、并发症情况,术后1mo每组处死12只兔子,摘除眼球,12眼(两组各6眼)作病理切片检查,HE染色观察炎症细胞情况;另12眼(两组各6眼)用α-SMAWholemount染色法观察兔角膜内皮细胞瘢痕和肌成纤维细胞情况并进行细胞计数。结果:实验组角膜术后一直维持透明,对照组在术后5d明显变混浊,眼压、前房反应和并发症在两组间差异无显著性(P>0.05)。术后1mo两组实验兔在单位面积(500μm2)肌成纤维细胞数和炎症细胞数均有显著性差异(t=5.716,6.991;P<0.05)。结论:深板层角膜内皮层移植应用于兔角膜内皮损伤模型中炎症反应小,前房反应轻,能保持角膜透明,且并发症少。