Identifying causes for poor visual outcome after DSEK/DSAEK following secondary DMEK in the same eye

Purpose: To identify causes of reduced visual acuity after Descemet stripping (automated) endothelial keratoplasty (DSEK/DSAEK) and to determine whether such eyes can be successfully ‘repaired’ with a secondary Descemet membrane endothelial keratoplasty (DMEK). Methods: Twelve eyes of 12 patients, who underwent secondary DMEK to manage poor visual outcome after initial DSEK/DSAEK, were evaluated with biomicroscopy, Pentacam imaging, and specular and confocal microscopy, before and at 1, 3 and 6 months after DMEK. Results: Four causes of reduced optical quality of the transplanted host cornea could be identified in DSEK/DSAEK: five eyes (42%) showed large host‐Descemet remnants within the visual axis during surgery; six eyes (50%) irregular graft thickness; six eyes subtle ‘stromal waves’; and nine eyes (75%) high reflectivity at the donor‐to‐host interface. After DMEK graft replacement, all corneas cleared and achieved a best corrected visual acuity of ≥20/25 (≥0.8), except for one with a partial Descemet graft detachment. Pachymetry values decreased from 670 (±112) μm before to 517 (±57) μm after secondary DMEK. Higher‐order aberrations (Coma and Trefoil) at the posterior surface tended to be lower (p = 0.07) in DMEK grafts than in DSEK/DSAEK grafts. Conclusion: Host‐Descemet remnants at the donor‐to‐host interface, interface reflectivity, graft thickness irregularity and donor stromal contraction may contribute to poor visual outcome after DSEK/DSAEK, without causing permanent host corneal damage, as in most cases, complete visual recovery could be achieved by performing a secondary DMEK.     

DSAEK or DMEK for failed penetrating keratoplasty: a systematic review and single-arm meta-analysis

International Ophthalmology - To review the published literature on indications and outcomes of DSAEK/DSEK and DMEK for the treatment of failed penetrating keratoplasty. This is a systematic review...     

Visual outcome and histological findings following femtosecond laser-assisted versus microkeratome-assisted DSAEK

Background

The aim of this study was to compare the visual outcome of femtosecond laser-assisted Descemet stripping automated endothelial keratoplasty (DSAEK) to microkeratome-assisted DSAEK as well as to contrast precut versus surgeon-cut grafts. Histologic characterization of failed DSAEK grafts was performed in order to correlate ultrastructural changes with graft failures.

Methods

In this case control study, 47 cases of DSAEK were investigated in terms of visual acuity, keratometric astigmatism, spherical equivalent, endothelial cell count, and postoperative complications. We formed three groups: the femtosecondlaser-assisted DSAEK with precut grafts, the microkeratome-assisted DSAEK with precut and with surgeon-cut grafts. Mean follow-up was 6 months. In the case of graft failure, penetrating keratoplasty was performed, and the excised corneal buttons were investigated by light and electron microscopy.

Results

Microkeratome-assisted DSAEK lead to better visual outcome than femtosecond laser-assisted DSAEK. Keratometric astigmatism, spherical equivalent and endothelial cell count did not differ significantly between both methods. Precut and surgeon-cut grafts in microkeratome-assisted DSAEK did not show any significant difference regarding all upraised parameters. No definite histological correlate for graft failure following femtosecond laser-assisted DSAEK was found.

Conclusions

Femtosecond laser-assisted DSAEK is not the method of choice, and needs further technical improvement. However, failed femtosecondlaser-assisted DSAEK grafts did not show significant histological changes related to the technique to explain reduced visual acuity. In microkeratome-assisted DSAEK, the preparation time point of the graft does not seem to influence the visual and optical outcome.     

Comparison of endoscopic revision for failed primary external versus endoscopic dacryocystorhinostomy

Backgound: To compare differences in endoscopic revision after previously failed lacrimal surgery that involved either external or endoscopic dacryocystorhinostomy. Design: Retrospective, comparative, nonrandomized clinical study. Participants: We assessed 77 patients (82 surgeries) treated for recurrent nasolacrimal duct obstruction. Methods: Electronic medical records for patients with recurrent epiphora who underwent endoscopic revisional dacryocystorhinostomy, after previous external or endoscopic dacryocystorhinostomy at Seoul St. Mary's Hospital from 2004 to 2010, were reviewed. Main Outcome Measures: Data regarding the lacrimal drainage system, comprehensive eye examination, surgical outcome and preoperative/perioperative transnasal endoscopy were analysed. Results: In total, 77 patients underwent 82 endoscopic revisional dacryocystorhinostomy procedures. A success rate of 84% was achieved for cases of previous external dacryocystorhinostomy and 80.7% for previous endoscopic dacryocystorhinostomy (P = 0.722). For preoperative nasal endoscopy, more of the patients who underwent previous external dacryocystorhinostomy exhibited a hypertrophic middle turbinate and severe septal deviation when compared with patients who underwent previous endoscopic dacryocystorhinostomy (P = 0.031, P = 0.001, respectively). For perioperative nasal endoscopy, more of the patients who underwent previous endoscopic DCR exhibited a smaller ostium when compared with patients who underwent previous external dacryocystorhinostomy (P = 0.031). Conclusions: The success rate of revisional dacryocystorhinostomy in the previous external dacryocystorhinostomy group was slightly higher than that in the previous endoscopic dacryocystorhinostomy group. Differences in preoperative and perioperative endoscopic findings were detected between the groups. Clarifying these differences in endoscopic revision will help improve the surgical outcomes of primary surgery involving either external or endoscopic dacryocystorhinostomy.     

Comparison of ultrasonic pachymetry with orbscan in corneal haze

Background To compare the results of ultrasonic and Orbscan pachymetry in corneal haze not related to surgery. Methods An institutionally based, prospective, controlled clinical trial included 40 eyes of 40 consecutive patients with corneal haze not related to surgery. Fifty normal eyes were used as a control group to calculate the customized acoustic factor. Corneal haze was graded with slit-lamp by a single examiner. Ultrasonic and Orbscan II pachymetry measurements were obtained. Paired t- and Kruskal-Wallis tests were used to evaluate the difference between ultrasonic and Orbscan pachymetry measurements. Correlation of the two methods and haze grade were determined with Kendall’s tau-b correlation analysis. Results Eighty-five percent of patients had moderate haze. With the customized acoustic factor, Orbscan values were significantly smaller than ultrasonic pachymetry measurements (p = 0.001, paired samplet-test). Increased haze grade resulted in smaller Orbscan pachymetry measurements however, this difference was insignificant (p = 0.444, Kruskal-Wallis test). A positive correlation was found between two methods, though insignificant (p = 0.064, Kendall’s tau-b correlation). When grouped in respect of diagnoses, differences in pachymetry measurements as well as the correlation were not significant (p > 0.05). Conclusion An insignificant positive correlation was found between the two methods in the presence of corneal haze. Orbscan measurements were inversely related to haze grading, and were significantly lower than ultrasonic pachymetry. According to our results, we recommend that clinicians should not count on Orbscan topography alone in the presence of corneal haze. Financial support was obtained from Baskent University, Ankara, Turkey [project # KA05/207] This study is registered at ClinicalTrials.gov with the registration ID# NCT00439114. None of the authors has any proprietary or financial interest in any product or device used in this study.     

Correlation between visual acuity and interface reflectivity measured by pentacam following DSAEK

Purpose: Descemet‐stripping automated endothelial keratoplasty (DSAEK) is an advanced method of lamellar endothelial keratoplasty. In comparison with penetrating keratoplasty, visual rehabilitation seems to be faster. Final visual outcome of DSAEK, however, seems to be limited, especially in comparison with Descemet membrane endothelial keratoplasty (DMEK). DSAEK cases without graft failure often do not show any definite correlate for the reduced optical performance. In this study, we tried to correlate visual acuity following DSAEK with interface reflectivity as measured by a rotating Scheimpflug system. Methods: We examined 14 eyes of 13 patients with the pentacam for 2–11 months following DSAEK. Reflectivity of the interface region in the centre of the optical axis as well as central corneal thickness was determined. Statistical correlation between interface reflectivity and best spectacle‐corrected visual acuity, central corneal thickness and follow‐up time was drawn (multifactorial linear regression analysis). Results: Statistically significant correlation between interface reflectivity and BSCVA as well as follow‐up time was found. Reflectivity was highest in regions of interface (metal) particles. There was no statistically significant correlation between interface reflectivity and central corneal thickness. Conclusion: We present a measurable correlate for reduced visual outcome following DSAEK despite a clear graft. Inverse correlation between interface reflectivity and best spectacle‐corrected visual acuity (BSCVA) indicates that irregularities or scarring in the interface region may influence the optical quality following DSAEK.     

Study of factors for unsuitability of DSAEK in cases of corneal decompensation following cataract surgery

To evaluate suitability of Descemet's stripping automated endothelial keratoplasty (DSAEK) in cases of corneal decompensation following cataract surgery. In this cross-sectional case series, 90 eyes of 90 patients were evaluated at a tertiary eye care centre. Cases with central corneal scarring or vascularisation, complicated aphakia with significant iris tissue defects and extensive synechaie or posterior segment pathology precluding visual recovery were classified as unsuitable for DSAEK. Of 90 eyes, 42 (46.67%) were unsuitable for DSAEK. Multivariate logistic regression analysis, revealed that patients presenting more than a year after cataract surgery had 7.5-fold odds of being unsuitable for DSAEK as compared with those who presented earlier(OR 7.5; CI 2.0-29.1). Patients with BCVA poorer than 0.06 at initial presentation had 5.0 times odds of being unsuitable for DSAEK (OR 5.0; CI 1.0-24.2). Patients who had prior non-phacoemulsification cataract surgery were 5.5 times less likely to be candidates for DSAEK as compared to those who had prior phacoemulsification (OR 5.5; CI 1.5-19.9) and those with anterior chamber IOL or aphakia were 5.0 times less likely suitable for DSAEK, in contrast to posterior chamber intraocular lenses (OR 5.0; CI 1.3-18.7). The type of cataract surgery, time to presentation and initial visual acuity play a role in determining the suitability of performing DSAEK in patients with corneal decompensation after cataract surgery.     

Impact of preoperative visual acuity on Descemet Membrane Endothelial Keratoplasty (DMEK) outcome

Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate whether and how preoperative visual acuity predicts visual acuity outcome after Descemet Membrane Endothelial...     

Blepharokeratoconjunctivitis in childhood: corneal involvement and visual outcome

Purpose

The main objective of this study is to describe the prevalence, degree and risk of corneal involvement, and visual impact in a pediatric population with blepharokeratoconjunctivitis (BKC).

Methods

Retrospective, observational, case–control study. Clinical records of patients ≤16 years old with BKC seen between 2006 and 2012 were reviewed. The prevalence and relative risk of corneal involvement was evaluated between patients with and without corneal affection through a univariate and multivariate analysis with logistic regression. Visual acuity at presentation and at last follow-up visit was also analyzed.

Results

One hundred and fourteen children with BKC, with a male-to-female ratio of 1 : 1 and a mean age at diagnosis of 9.13 years. The mean follow-up time was 26.4 (±25) months. Corneal involvement was present in 39.5% of patients, varying from superficial punctate keratitis to perforation. Corneal changes were not seen in children under 4 years old. The risk of corneal affection was greater in patients with photophobia, hordeolum, female gender and asymmetric disease (OR of 2.69, 11.6, 2.35 and 2.77, respectively). The mean best-corrected visual acuity at presentation was 0.20 (corneal affected group), compared to 0.11 (unaffected group; P=0.02).

Conclusions

Our study showed an older age at time of diagnosis and a worse visual outcome in patients with BKC and corneal disease compared with previous reports. Early diagnosis and detection of risk factors for corneal involvement, as well as adequate treatment, is mandatory to prevent serious long-term visual repercussions in children with BKC.     

Correlation between TGF-beta1 in tears and corneal haze following LASEK and epi-LASIK

PURPOSE: To compare the incidence and degree of corneal haze formation following laser subepithelial keratomileusis (LASEK) and epithelial laser in situ keratomileusis (epi-LASIK), and examine its correlation with tear film transforming growth factor-beta1 (TGF-beta1) levels. METHODS: This prospective, interventional, clinical trial included 20 eyes (20 patients) randomly assigned to undergo LASEK or epi-LASIK. The level of TGF-beta1 in tear fluid was measured preoperatively and 1, 3, and 5 days postoperatively. Corneal haze was graded at 1 and 3 months after surgery, and the relationship with TGF-beta1 levels was determined. RESULTS: Mean preoperative spherical equivalent refraction was -4.50 +/- 1.44 diopters (D) (range: -1.50 to -6.00 D) for LASEK eyes and -4.90 +/- 1.26 D (range: -1.75 to -6.00 D) for epi-LASIK eyes. Although mean corneal haze scores at 1 month were significantly higher in LASEK-treated eyes than in epi-LASIK treated eyes (P=.031), these scores were similar at 3 months (P=.608). Tear fluid TGF-beta1 levels were similar in LASEK and epi-LASIK eyes before surgery (P=.458) and significantly higher in the LASEK group at 1, 3, and 5 days postoperatively (P=.015, P=.023, and P=.039, respectively). A positive correlation was noted between tear TGF-beta1 levels on the first postoperative day and the degree of corneal haze at 1 month (r=0.501, P=.016). CONCLUSIONS: Less corneal haze was noted after epi-LASIK than LASEK. A positive correlation between corneal haze and tear fluid TGF-beta1 levels on the first postoperative day suggest a possible mechanism for the observed difference.     

Five-year follow-up of corneal morphology and corneal refractive power changes after uneventful DMEK

Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate changes of corneal thickness spatial profile (CTSP), corneal volume (CV) distribution, and total corneal refractive...     

Long-term visual outcome in primary microtropia

PURPOSE: To study the long-term visual outcome of primary microtropia. METHODS: A retrospective review was made on 31 patients with primary microtropia with the follow-up period of 5 years or more (5-15 years, mean=9.2 years) seen during 16 years from 1985 to 2000 at Okayama University Hospital. The patients were 16 boys and 15 girls, with the age at the initial visit ranging from 5 to 16 years (mean=9.3 years). RESULTS: All patients showed anomalous retinal correspondence, peripheral fusion, 10 prism diopters or smaller esodeviation at the initial and final visit. At the initial visit, TNO stereoacuity was absent in 24 patients, 480 seconds in 3, and 240 seconds in 4. The visual acuity was 0.8 or better in both eyes of 16 patients, but 0.7 or worse in 1 eye or both eyes of 15 patients. At the final visit, the 24 patients with the absence of stereoacuity still showed its absence, while stereoacuity remained unchanged or improved in the 7 patients with initial stereoacuity of 480 seconds or better. In the 15 patients with 0.7 or worse visual acuity, it improved to 0.8 or better in 7 patients while it remained 0.7 or worse in the other 8 patients. Poor visual acuity had no relation to the absence of TNO stereoacuity at the initial and final visits. CONCLUSION: Patients with primary microtropia could be largely classified into those with the absence of TNO stereoacuity throughout the course of treatment and those with some levels of stereoacuity that had a chance to improve during the follow-up.     

丝裂霉素C和角膜水化对准分子激光上皮下原位磨镶术后角膜上皮下混浊的不同影响

目的比较分析准分子激光上皮下原位磨镶术（LASEK）中使用0．02％裂霉素C（MMC）和角膜水化两种不同方法对术后角膜上皮下混浊（Haze）形成的影响。方法将接受LASEK手术的高度47例近视眼患者,术中对一眼在激光消融结束后角膜瓣下使用0．02％MMC,另一眼在切削1／2脉冲总量时,用低于20℃生理盐水冲洗（角膜水化）,比较术后双眼角膜Haze发生情况。结果MMC组和角膜水化组比较：发生角膜Haze的差异程度有统计学意义（P〈0．01）。结论LASEK术中使用0．02％丝裂霉素c在抑制术后Haze形成中优于角膜水化。     

前节OCT与超声角膜测厚仪在角膜内皮移植术后测量中央角膜厚度的比较

目的 比较角膜内皮移植(DSAEK)术后后眼前节相干光断层扫描(AS-OCT)与超声角膜测厚仪测量的中央角膜厚度(CCT),评估两种方法的一致性,为AS-OCT的临床应用提供客观依据.方法 分别应用AS-OCT与超声角膜测厚仪测量DSAEK后患者38例(41只眼)的CCT,对两种方法所得的测量值进行配对t检验及Pearson相关分析,并采用Bland-Altman plot进行一致性评价.结果 AS-OCT与超声角膜测厚仪测量CCT的平均值分别为(728.73±138.39)μm和(718.56±131.37)μm;两组数据差异无统计学意义(t=-1.170;P=0.249).通过Pearson相关性分析,这两种方法的测量值成正相关(r=0.916,P ＜0.01).AS-OCT与超声角膜测厚测量值的一致性较好.结论 DSAEK后,AS-OCT与超声角膜测厚两种测量方法的一致性较好,但由于前者所具备的独特优势,AS-OCT可以作为DSAEK后长期随访角膜厚度变化的一种有效的检测工具.

Abstract：

Objective To assess the agreement of central corneal thickness ( CCT) measured by anterior segment-optical tomography (AS-OCT) and ultrasonic pachymeter after Descemet's Stripping with Automated Endothelium Keratoplasty (DSAEK) and provide objective basis for clinical application of AS-OCT. Methods Forty-one eyes of 38 patients after Descemet's Stripping with Automated Endothelium Keratoplasty (DSAEK) underwent CCT measurement by AS-OCT and ultrasonic pachymeter.The data was analyzed by paired-t test and Pearson correlation analysis. Bland-Altman plot was used to assess the agreement.Results The mean CCT values were(728.73±1 38.39)μ m measured by AS-OCT and (718.56+131.37)μ m measured by ultrasonic pachymeter,and there was no significant difference between the two methods. Regression analysis showed a high correlation between the values obtained by both devices (r =0.916, P＜0.01). AS-OCT and ultrasonic pachymeter showed a less a-greernent in CCT measurement after DSAEK. Conclusions After DSAEK, there is a reasonable agreement between two techniques, AS-OCT and ultrasonic pachymeter of CCT measurements. Considering the special advantages, AS-OCT is an effective method to observe the changes of the corneal thickness in the long term.     

Influence of wavefront aberration and corneal subepithelial haze on low-contrast visual acuity after photorefractive keratectomy

PURPOSE: To assess low-contrast visual acuity (LCVA) after photorefractive keratectomy in relation to ocular higher-order wavefront aberration and corneal subepithelial haze. DESIGN: Prospective, cross-sectional analysis. METHODS: Photorefractive keratectomy was performed in 51 eyes of 27 subjects with myopic refractive error of -2.0 to -10.5 diopters. Ocular higher-order wavefront aberrations for a 4-mm pupil were measured using Topcon Hartmann-Shack wavefront aberrometer, and the extent of corneal subepithelial haze was quantified with Nidek TSPC-3 hazemeter before and 1 month after photorefractive keratectomy. Low-contrast visual acuity was recorded with Vector Vision CSV-1000LanC10% chart. Total higher-order, third-order (coma-like), and fourth-order (spherical-like) aberrations of the eye were determined. The influence of wavefront aberration and corneal subepithelial haze on LCVA was analyzed. RESULTS: Total higher-order, third-order, and fourth-order aberrations significantly increased by surgery (P < .001, Wilcoxon signed rank test). Photorefractive keratectomy induced a significant increase in corneal haze (P < .01), but no case presented severe corneal haze (grade 3 or greater by Fantes grading). By surgery, LCVA was reduced significantly (P < .001). The logarithm of the minimal angle of resolution LCVA showed a significant correlation with total higher-order aberration (Spearman rank correlation coefficient, r(s) = 0.642, P < .0001). Both third-order (r(s) = 0.618, P < .0001) and fourth-order aberrations (r(s) = 0.552, P < .0001) also significantly correlated with logarithm of the minimal angle of resolution LCVA. There was no correlation between the degree of corneal haze and logarithm of the minimal angle of resolution LCVA (r(s) = 0.094, P = .523). CONCLUSIONS: In eyes with mild to moderate corneal haze after photorefractive keratectomy, deterioration of LCVA is mainly attributable to increases in wavefront aberration, and not to corneal haze.     

Objective assessment of transient corneal haze and its relation to visual performance after photorefractive keratectomy

PURPOSE: Photorefractive keratectomy has the potential to cause transient corneal haze. The purpose of this study was to evaluate the relationship between transient corneal haze as measured by an objective means and high and low contrast visual performance. METHODS: In a prospective study, 44 eyes of 28 patients were examined preoperatively and at 1, 3, 6, and 12 months after photorefractive keratectomy. Five laser in situ keratomileusis and two intrastromal corneal ring segments (Intacs [KeraVision, Fremont, CA]) were included for comparison, because these procedures are not expected to cause haze. Haze was measured using a prototype objective hazemeter, TSPC-3, a modification of the Nidek EAS-1000. Visual performance was measured using high-contrast visual acuity and the Rabin Small Letter Contrast Test. RESULTS: Corneal haze was greatest at the 1-month examination and was consistent with a decrease in visual performance on both tests. Corneal haze resolved in 82% of eyes by 10 +/- 4 months after photorefractive keratectomy. However, visual performance had not returned to preoperative levels in 65% and 81% of these eyes on the high-contrast visual acuity test and the Small Letter Contrast Test, respectively. Eyes that underwent laser in situ keratomileusis and Intacs did not develop corneal haze; however, visual decrements were measured. CONCLUSIONS: As a clinical tool, the TSPC-3 hazemeter objectively measures very subtle changes in haze levels. Corneal haze appears to account for only approximately 50% of visual performance changes in the early healing period after photorefractive keratectomy. Other factors, namely topographic abnormalities, are more likely to be an important cause of persistent visual disturbances.