Late corneal ectasia after penetrating and deep anterior lamellar keratoplasty for keratoconus

AIM:To investigate tomographic features of late corneal ectasia after keratoplasty for keratoconus and compare penetrating keratoplasty(PK)and deep anterior lamellar keratoplasty(DALK)in terms of incidence,time of onset and risk factors of corneal ectasia.METHODS:Sixty eyes with PK and 30 eyes with DALK operated between 1999 and 2021 were analyzed.Final Pentacam scans were evaluated together with vision and previous topographies.Main outcome measures were vision,K values,apparent thinning on graft-host cornea and the difference between opposing quadrants in the thinnest point measurements.Anterior segment optic coherence tomography was performed for further evaluation.RESULTS:Mean follow-up was 127.2mo(24–282mo)in PK,and 64.3mo(24–144mo)in DALK.K max was higher in DALK(60.6 vs 56.7 D,P=0.012).Inferior recipient was thinner(595.9μm)in PK than DALK(662.2μm,P=0.021),due to longer follow-up.Overall corneal ectasia rate was 20.0% within 24y.Ectasia rate was the same(6.7%)in DALK 2/30 and in PK 4/60 in 10y and 13.3%in 12y(4/30 and 8/60,respectively).It increased to 23.3%(14/60)in PK over 24y.While ectasia was not seen before 7y in PK,it could be seen in DALK starting from the 5^(th) year.The intervals between keratoplasty and ectasia were 144.5mo in PK and 99mo in DALK.Inferior recipient was significantly thinner in 18 eyes with ectasia(502.7μm)compared to 76 non-ectasia(649.1μm,P=0.000).Inferior graft was thinner(561.0 vs 620.4μm,P=0.006),K max(63.3 vs 56.5 D,P=0.000),and anterior elevation was higher in ectasia(89.1 vs 48.6μm,P=0.002).Accelerated crosslinking was performed on 5 eyes.CONCLUSION:Inferior-superior recipient and inferior graft thinning on tomography,with high K max and anterior elevation emerge as the most reliable criteria for the diagnosis of late ectasia.The incidence of corneal ectasia increases with the time.

Endoscopy-assisted vitrectomy for severe ocular penetrating trauma with corneal opacity

AIM:To assess the utility and efficiency of endoscopyassisted vitrectomy(EAV)for the treatment of corneal opacity in severe ocular trauma.METHODS:Patients who underwent fundus examination using a preoperative slit lamp and intraoperative endoscopy,followed by EAV and additional surgery were retrospectively recruited.Silicone oil removal and penetrating keratoplasty were used in selected eyes at postoperative follow-ups.Outcome measurements included the best corrected visual acuity(BCVA),intraocular pressure(IOP),findings of endoscopic fundus examination,and postoperative complications.RESULTS:Twenty-one eyes with severe ocular trauma and corneal opacity were followed up for 24-36mo.Retinal detachment(RD)and vitreous haemorrhage(VH)were identified in 16 eyes(76.2%),RD only in four eyes(19.0%),and VH combined with intraocular foreign body in one eye(4.8%).All eyes underwent at least three surgeries.Stage-Ⅰ surgeries involved wound closure(100%),lens extraction(76.2%),and anterior vitrectomy(14.3%).Stage-Ⅱ surgeries involved scleral buckling(28.6%),membrane peeling(47.6%),retinal laser photocoagulation(100%)and silicone oil tamponade(100%)using EAV.Stage-Ⅲ surgeries were conducted using endoscopy including silicone oil removal(52.4%),retinal laser photocoagulation(52.4%)and penetrating keratoplasty(28.6%).Nearly all eyes showed improvements in BCVA and IOP.Although there were no severe complications,glaucoma was noted in one eye,chronic hypotony in another eye,and band keratopathy in three eyes.CONCLUSION:EAV is an effective adjunct for restoring ocular anatomical structures and visual function in the case of corneal opacity after severe ocular trauma.

Effect of corneal graft diameter on therapeutic penetrating keratoplasty for fungal keratitis

AIM: To evaluate the effect of corneal graft diameter on therapeutic penetrating keratoplasty(PKP) for fungal keratitis. METHODS: A total of 116 patients (116 eyes) suffered from fungal keratitis underwent PKP at the Affiliated Hospital of Medical College Qingdao University from May 2006 to May 2010. They were divided into two groups according to the corneal graft diameter. 64 eyes' corneal graft diameter was 8.00mm or larger and 52 eyes' graft diameter was smaller than 8.00mm. The follow-up time was 2 years. The postoperative visual acuity and complications were documented and compared. RESULTS: Sixty-two (96.88%) eyes and fifty (96.15%) eyes preserved eyeballs respectively in two groups. There was no statistical difference in postoperative visual acuity (P = 0.961), corneal graft dear rate (P=0.132) or the incidence of recurred fungal infection (P=0.770) between two groups. But there was a higher incidence of graft rejection (P=0.020) and secondary glaucoma (P=0.039) in group with corneal graft diameter 8.00mm or larger. CONCLUSION: PKP is an effective treatment approach for fungal keratitis. There is a higher incidence of complications in large-diameter PKP for fungal keratitis.Effective, preventive and therapeutic measures can improve the prognosis.

Accelerated versus standard corneal cross linking in the treatment of ectasia post refractive surgery and penetrating keratoplasty: a medium term randomized trial

AIM: To compare the clinical outcomes of the standard corneal cross linking(CXL) and the accelerated CXL in patients with progressive corneal ectasia post refractive surgery and penetrating keratoplasty.METHODS: Totally 120 eyes of 83 patients scheduled to receive either standard CXL(3 m W/cm^2 for a period of 30 min) or accelerated CXL(18 m W/cm2 for a period of 5 min). The main outcomes for comparison were the change in: maximum-K reading(K-max), manifest refractive spherical equivalent(SE), central corneal thickness(CCT), and the best corrected distance visual acuity(CDVA).RESULTS: One hundred and eleven eyes completed the study. The main outcome measurement was the K-max reading. Both group showed significant improvement in the value postoperatively at 6 and 12 mo. The mean change in the standard group was 1.21±0.11 D and in the accelerated group was 0.90±0.05 D at the end of 12 mo postoperatively, with no statistically significant difference between the 2 groups. Similarly, CDVA improved significantly from their preoperative value in the standard group by 2.98±0.11 letters, and in the accelerated group by 2.20±0.06 letters, with no statistically significant difference between the two groups. Both of the SE, and CCT showed no statistically significant difference at the end of follow up period in each group.CONCLUSION: Both standard CXL and accelerated CXL are safe and effective treatment in halting ectasia after corneal refractive surgery. The accelerated CXL results are comparable to the standard CXL with short time exposure of the cornea to ultraviolet irradiation, leading to reduced operation time, reduced operative ocular discomfort, and corneal haze.

Penetrating keratoplasty in children under 3 years old with congenital corneal opacities

AIM:To evaluate the graft rejection and visual outcomes after penetrating keratoplasty(PK)in the presence of various congenital corneal opacities in children.METHODS:In this retrospective cohort study,children who underwent PK were then followed for 5 y.The patient’s medical records were collected from June 2014 until June 2019 and analyzed in December 2019.All patients were children under three years old with congenital corneal opacities with or without microcornea who came to a pediatric ophthalmologist and underwent PK in Jakarta Eye Center(JEC).Beforehand,all children have participated in a thorough evaluation for PK.In the case of severe microcornea was not advised to undergo surgery.The visual outcomes and graft survival rate were described in percentages.The graft survival plot was presented with Kaplan-Meier,while the visual acuity was analyzed using the Wilcoxon signed ranks test.RESULTS:Sixteen eyes from eleven patients(seven girls and four boys)underwent PK.The graft survival rate of the first 6,12,and 18 mo later of keratoplasty was 100%,83.3%,and 66.7%,respectively.The overall mean survival time is 22 mo(standard error 2.419),and no significant difference between the patients underwent PK before and after 36 mo of their age(P=0.52).The graft failure was 50%,and postsurgery complications included cataract 43.7%,band keratopathy 12.5%,and scleromalasia 6.25%.Wilcoxon test analysis of visual acuity post keratoplasty was not statistically significant(P=0.34),while overall showed 44%improvements of visual outcome for 5 y of follow-up.With a good survival at one year up to 22 mo(83.3%),the visual acuity could be achieved(63%),and showed improvements(44%)during follow-up.CONCLUSION:The complications are frequent for pediatric PK.Thus,corneal surgery on infants requires careful case selection,adequate pre-operative evaluation,skilled surgery(optical correction),very close cooperation family–physician,intensive post-operation care,and amblyopia management in the future.

Simultaneous tectonic Descemet stripping endothelial keratoplasty and tectonic Bowman layer transplant for the management of corneal perforation

AIM:To report the outcomes of three cases of corneal perforation managed with simultaneous tectonic Descemet stripping endothelial keratoplasty(t-DSEK)and tectonic Bowman layer transplant(t-BLT)as an alternative to tectonic penetrating keratoplasty(t-PKP).METHODS:Three eyes of three patients receiving simultaneous t-DSEK and t-BLT for corneal perforation were included.The technique for DSEK was modified depending on individual requirements.The t-BLT technique was standardised using an 8 mm graft and fixated with a running suture.Success was measured by the ability of this procedure to close a corneal perforation.RESULTS:All three cases achieved tectonic eye globe restoration and remained stable during the minimum 3-month observation period.Reinterventions were relatively common:2 cases required amniotic membrane transplant for persistent epithelial defects.One case required DSEK rebubbling.One case developed angle closure glaucoma requiring surgical peripheral iridectomy.CONCLUSION:Simultaneous t-DSEK and t-BLT may be a useful strategy for the management of corneal perforation as an alternative management to t-PKP for selected cases.

Posterior corneal astigmatism modifications after cataract surgery and its role on total corneal astigmatism

Background:In recent years posterior corneal astigmatism and its effect on total corneal astigmatism has been studied,with research showing that this can impact total astigmatism.This study aims to ascertain if there is significant change in the posterior corneal astigmatism after cataract surgery and its impact on the total astigmatism.Methods:Analysis of 76 eyes that underwent cataract surgery with monofocal intraocular lens implantation.Corneal topography was performed with Pentacam(OCULUS®)pre-and post-operatively.Total corneal astigmatism was calculated with the algorithm of vergence tracing.We compared preoperative and postoperative changes in the magnitude and axis differences of anterior corneal curvature astigmatism,posterior corneal curvature astigmatism and the calculated total corneal astigmatism.We calculated the correlation between the total preoperative astigmatism and the difference between total corneal astigmatism and anterior corneal astigmatism.Results:The mean preoperative and postoperative posterior astigmatism was 0.31±0.02 D,showing no significant differences before and after surgery(P=0.989).Statistically significant differences between the calculated total corneal astigmatism and anterior corneal astigmatism were registered preoperatively and postoperatively in the with-the-rule anterior(WTR)corneal astigmatism(P=0.004,P<0.0001);against-the-rule(ATR)anterior corneal astigmatism(P<0.0001,P<0.0001)and in the oblique(P=0.026,P=0.019)subgroups.The posterior corneal astigmatism and the total corneal astigmatism correlated positively with the differences between the total corneal and anterior corneal astigmatism(R=0.378,P=0.001).Conclusions:There were statistically significant differences between the magnitude of the total astigmatism and anterior corneal astigmatism,underlining the impact of posterior corneal astigmatism.A positive correlation between the preoperative posterior astigmatism and the difference between the total corneal and the anterior corneal astigmatism suggests a specially relevant role of posterior corneal astigmatism when evaluating patients with higher degrees of astigmatism.

Case report:simultaneous femtosecond laser astigmatic keratotomy and toric intraocular lens implantation in femtosecond laser-assisted cataract surgery in a patient with surgically induced high corneal astigmatism

Background:Femtosecond laser astigmatic keratotomy(FSAK)and toric intraocular lens(IOL)implantation have been studied individually for comparison to treat astigmatism at cataract surgery.We report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty(LTK)in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery(FLACS).This is the first report of both procedures combined simultaneously,with or without history of LTK.Case Description:A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004,with subsequent surgically induced high corneal astigmatism,and with age-related nuclear cataract of both eyes.IOL master demonstrated+7.71 diopters of astigmatism at 163 degree right eye and+3.29 diopters of astigmatism at 4 degree left eye.After extensive discussion of the risks and benefits,the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions(RIs)and toric IOL(Alcon SN6AT9)right eye;FLACS with toric IOL(Alcon SN6AT7)alone left eye.At 2-year follow-up,uncorrected visual acuity was 20/30 right eye,20/25 left eye.His best corrected visual acuity was 20/25(+0.25+1.00 axis 21)right eye and 20/20(plano+0.25 axis 90)left eye;his best corrected near visual acuity was J1+with add+2.50 diopters right eye and left eye.Conclusions:Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract surgery.An effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9,in our case,simultaneously,which can achieve an excellent long term visual outcome.

Morphometric study of endothelial wound-healing following penetrating keratoplasty

Twenty samples of endothelia removed from normal and post penetrating keratoplas-ty (0.5,1,2,3 months after penetrating keratoplasty) were observed by scanning electron mi-croscopy.The photographs of the endothelia in graft-host junction were analyzed by computer-assisted image analysis system,and the morphometric indexes examined were area of the cells,perimeters,density,figure coefficient,long axis,coefficient of variation of the area,and oth-ers.Results showed that the morphology and the density of the endothelial cells changed obvi-ously after operation and improved slowly but progressively with time although at 3 monthspostoperatively some differences still existed.By using the new techniques,the experiment con-firmed and enriched the theories on the corneal endothelial wound-healing,revealing some ofthe new characters of the endothelial wound-healing following penetrating keratoplasty.

Changing trends in corneal graft surgery： a ten-year review

AIM：To review indications and corneal tissue use for penetrating and lamellar surgery between 2002 and 2011.·METHODS：The surgical reports of corneal grafts performed during 2002-2011,using tissues supplied by the Eye Bank of Piedmont（Italy）,were reviewed retrospectively.Patient demographic data,date of intervention,indication for surgery,and surgical technique used were recorded.Surgical techniques included penetrating keratoplasty（PK）,deep anterior lamellar keratoplasty（DALK）and endothelial keratoplasty（EK）.The2test was used to compare the distribution of indications and types of surgical technique used,for corneal grafts done during 2002-2006 versus those done during 2007-2011.·RESULTS：The number of corneal grafts increased by30.7%from 2002-2006 to 2007-2011（from 1567 to 2048）.Comparing the two periods,both main indications and surgical techniques changed significantly.In 2007-2011,the proportion of interventions for aphakic/pseudophakic bollous keratopathy（from 16.8%to 21.3%）,graft failure（from 16.4%to 19.1%）and Fuchs endothelial dystrophy（from 12.8%to 16.7%）all increased significantly（〈0.05）,while those for keratoconus decreased significantly（from35.6%to 27.3%;〈0.001）.In 2007-2011,the proportion of PK decreased significantly（from 92.4%to 57.2%;〈0.001）while that of EK and DALK went from 0.4%to48 30.2%（〈0.001）and from 7.2%to 12.6%（〈0.001）respectively.·CONCLUSION：During 2002-2011 the number of interventions increased significantly for corneal endothelial diseases and graft failure.The growing demand for interventions for these diseases corresponded to the widespread adoption of EK techniques.The use of DALK also increased,but more moderately than EK procedures.

PENETRATING KERATOPLASTY COMBINED WITH CATARACT EXTRACTION

The authors report the results of penetrating keratoplasty combined with cataract extraction in 50 cases. The rate of transparent grafts was 62％ after an average follow-up of 19 months. 60％ of the patients restored their vision to 0.1 and better. The rate of transparent grafts and visual improvement did not correlate with the mode of cataract extraction; however, the extracapsular procedure had less vitreous during operation than the intracapsular modality did. The authors recommend that the combined operation be adopted for patients with corneal opacity and cataract, and preferably using the extracapsular mode.

Donor cornea quality used for penetrating keratoplasty vs deep anterior lamellar keratoplasty

Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.

Large Penetrating Keratoplasty in the Management of Keratoglobus: A Case Report

Background: Keratoglobus is a rare noninflammatory corneal disorder characterized by diffuse corneal thinning and globular protrusion of the cornea. Surgical management of keratoglobus is challenging and the standard method has not yet been defined. Aim: To present the role of large penetrating keratoplasty (PK) in the management of keratoglobus. Case Presentation: A 29-year-old male patient with bilateral keratoglobus presented with acute corneal hydrops in his right eye following extensive Descemet’s membrane rupture, with a visual acuity in this eye limited to hand movement. Peripheral cornea was extremely thin and blue sclera was present. Acute hydrops was managed conservatively at this stage and two months later large PK was performed in the right eye using 9.5 mm diameter graft over a 9 mm patient’s cornea trephination. Minor aqueous leakage was seen on the first postoperative day, managed with 2 more interrupted 10.0 nylon sutures. No further complications were noticed and postoperative course was uneventful. Fifteen months postoperatively the graft was clear and best corrected visual acuity was 20/60. Conclusions: Large penetrating keratoplasty has an important role in the management of keratoglobus, in cases where peripheral tuck-in lamellar keratoplasty or epikeratoplasty present serious intraoperative difficulties in host lamellar dissection and in stabilizing the graft due to extensive peripheral corneal and scleral thinning.

深板层角膜移植与穿透性角膜移植治疗基质角膜营养不良预后的比较

背景:基质角膜营养不良的传统手术治疗方式为穿透性角膜移植,近年来越来越多的医生开始考虑使用深板层角膜移植治疗基质角膜营养不良。目前国内对比穿透性角膜移植和深板层角膜移植治疗基质角膜营养不良的研究少有报道。目的:比较深板层角膜移植和穿透性角膜移植治疗基质角膜营养不良的疗效。方法:选择2000年1月至2018年1月北部战区总医院收治的基质角膜营养不良患者57例(57眼),男18例,女39例,平均年龄(52.9±20.0)岁,按照手术治疗方式分为深板层角膜移植组(n=21)、穿性角膜移植组(n=36),术后随访观察最佳矫正视力、角膜内皮细胞密度、角膜植片透明度、术中及术后并发症、原病复发情况。结果与结论:①两组患者术后1,3,6,12个月的视力均高于术前(P<0.05),两组间术后不同时间点的视力比较差异无显著性意义(P>0.05);随着术后时间的延长,两组患者角膜内皮细胞密度逐渐降低,穿透性角膜移植组患者术后6,12个月的角膜内皮细胞密度年丢失率均高于深板层角膜移植组(P<0.05);两组患者术后12个月的角膜植片透明率比较差异无显著性意义(P>0.05);②深板层角膜移植组有6例出现并发症,穿透性角膜移植组有14例出现并发症,57例患者术后12个月内均无复发,两组患者术后5年的复发率比较差异无显著性意义(P>0.05),穿透性角膜移植组和深板层角膜移植组术后5年的移植物存活率分别为83%和86%,组间比较差异无显著性意义(P>0.05);③结果表明,基质角膜营养不良的治疗可考虑使用深板层角膜移植替代一部分穿透性角膜移植。

Effects of Cataract Surgery on Endothelium in Transplanted Corneal Grafts： Comparison of Extracapsular Cataract Extraction and Phacoemulsification for Complicated Cataract after Penetrating Keratoplasty

Background： The endothelium should be carefully evaluated when choosing a surgical technique for cataract removal. Therefore, we aimed to study the effects of different cataract surgery techniques on endothelial cell loss in transplanted corneal grafts. Methods： A total of 54 patients who received complicated cataract surgery in post-penetrating keratoplasty （PKP） eyes at the Shandong Eye Institute between February 2001 and June 2014 were included, and clinical records were reviewed. Baseline demographic details, clinical characteristics, endothelial cell density （ECD）, and best-corrected visual acuity （BCVA） were recorded. Wilcoxon rank-sum test and Wilcoxon signed-rank test were used to test the equality of medians. A regression model was constructed to compare the reduced rate of ECD. Results： Of the 54 eyes included in this study, extracapsular cataract extraction （ECCE） was performed in 34 eyes of 33 patients （ECCE group） whereas phacoemulsification was performed in 20 eyes of 20 patients （phacoemulsification group）. There was no signifcant difference in the median age （P = 0.081） or preoperative ECD （P = 0.585） between the two groups. At 6 months after cataract surgery, ECD in ECCE group was significantly higher than that in phacoemulsification group （P = 0.043）. In addition, the endothelial cell loss rate in ECCE group was significantly lower than that in phacoemulsification group at 2 months （P = 0.018）, 4 months （P 〈 0.001）, and 6 months （P 〈 0.001） after cataract surgery. Endothelial cell loss rate after cataract surgery increased over the 6-month study duration in both ECCE group （P 〈 0.001） and phacoemulsification group （P 〈 0.001）, but phacoemulsification resulted in a greater reduction in ECD than that of ECCE in transplanted corneal grafts （P 〈 0.001）. There was no signifcant difference in postoperative BCVA between the two groups （P = 0.065）. Conclusion： ECCE is more suitable than phacoemulsification in cataract surgery in complicated cataract after PKP.

Ocular biomechanical measurements on post- keratoplasty corneas using a Scheimpflug-based noncontact device

AIM： To analyse ocular biomechanical properties, central corneal thickness （CCT） and intraocular pressure （lOP） in post-keratoplasty eyes, as compared to normal subjects, with a new Scheimpflug-based technology. Moreover, biomechanical data were correlated with the size and age of the donor and recipient corneas. METHODS： Measurements were conducted on 46 eyes of 46 healthy patients without any corneal pathology （age： 53.83 ±20.8y） and 30 eyes of 28 patients after penetrating keratoplasty （age： 49.43 ±21.34y）. Ten biomechanical parameters, the CCT and lOP were recorded by corneal visualization Scheimpflug technology （CorVis ST） using high-speed Scheimpflug imaging. Keratometry values were also recorded using Pentacam HR system. Scheimpflug measurements were performed after 43.41± 40.17mo （range： 11-128mo） after the keratoplasty and after 7.64±2.34mo （range： 5-14mo） of suture removal. RESULTS： Regarding the device-specific biomechanical parameters, the highest concavity time and radius values showed a significant decrease between these two groups （P=0.01 and P 〈0.001）. None of other biomechanical parameters disclosed a significant difference. The CCT showed a significant difference between post keratoplasty eyes as compared to normal subjects （P= 0.003） using the CorVis ST device. The lOP was within the normal range in both groups （P=0.84）. There were no significant relationships between the keratometric data, the size of the donor and recipient, age of the donor and recipient and biomechanical properties obtained by CorVis ST. CONCLUSION： The ocular biomechanics remain stable after penetrating keratoplasty according to the CorVis ST measurements. Only two from the ten device-specific parameters have importance in the follow-up period after penetrating keratoplasty.

不同设计角膜塑形镜治疗青少年近视伴散光的效果及对角膜透明度、曲率、内皮细胞及知觉变化的影响

目的探究不同设计角膜塑形镜治疗青少年近视伴散光的效果及对角膜透明度、曲率、内皮细胞及知觉变化的影响。方法前瞻性选取2019年4月至2022年4月于中国中医科学院眼科医院就诊的114例近视伴散光青少年患者为观察对象,采用区组随机化法分为观察组57例(114眼)和对照组57例(110眼)。对照组采用球面角膜塑形镜进行矫正,观察组使用Toric角膜塑形镜进行矫正。比较两组治疗6个月后临床效果[最佳矫正视力(BCVA)、散光值],比较两组治疗前、治疗6个月后角膜结构学(角膜光密度值、曲率)、角膜内皮细胞计数、视觉质量[对比敏感度函数(CSF)]的变化。结果治疗6个月后,观察组BCVA为0.72±0.18,显著高于对照组(0.67±0.16),散光值为(1.13±0.42)D,显著低于对照组[(1.54±0.58)D],差异均有统计学意义(P<0.05)。治疗6个月后,两组角膜光密度值、角膜前表面和后表面中心曲率、眼球内皮细胞计数比较,差异均无统计学意义(P>0.05)。治疗6个月后,观察组不同频段(高、中、低)无眩光下CSF值分别为1.85±0.17、1.66±0.15、1.02±0.21,均显著高于对照组(1.79±0.15、1.61±0.14、0.89±0.15),差异均有统计学意义(P<0.05)。结论近视伴散光青少年患者配戴Toric角膜塑形镜能提高视觉质量,显著改善患者视力控制近视的进展,且安全性好,适合临床推广。

The role of corneal endothelium in macular corneal dystrophy development and recurrence

Macular corneal dystrophy(MCD)is a progressive,bilateral stromal dystrophic disease that arises from mutations in carbohydrate sulfotransferase 6(CHST6).Corneal transplantation is the ultimate therapeutic solution for MCD patients.Unfortunately,postoperative recurrence remains a significant challenge.We conducted a retrospective review of a clinical cohort comprising 102 MCD patients with 124 eyes that underwent either penetrating keratoplasty(PKP)or deep anterior lamellar keratoplasty(DALK).Our results revealed that the recurrence rate was nearly three times higher in the DALK group(39.13%,9/23 eyes)compared with the PKP group(10.89%,11/101 eyes),suggesting that surgical replacement of the corneal endothelium for treating MCD is advisable to prevent postoperative recurrence.Our experimental data confirmed the robust m RNA and protein expression of CHST6 in human corneal endothelium and the rodent homolog CHST5 in mouse endothelium.Selective knockdown of wild-type Chst5 in mouse corneal endothelium(AC^(siChst5)),but not in the corneal stroma,induced experimental MCD with similar extracellular matrix synthesis impairments and corneal thinning as observed in MCD patients.Mice carrying Chst5 point mutation also recapitulated clinical phenotypes of MCD,along with corneal endothelial abnormalities.Intracameral injection of wild-type Chst5 rescued the corneal impairments in AC^(siChst5)mice and retarded the disease progression in Chst5 mutant mice.Overall,our study provides new mechanistic insights and therapeutic approaches for MCD treatment by highlighting the role of corneal endothelium in MCD development.

塞来昔布固体脂质纳米粒对兔角膜重度热烧伤行穿透性角膜移植术后CNV、MMP-2的影响

目的观察塞来昔布(celecoxib,CXB)固体脂质纳米粒(solid lipid nanoparticles,SLN)对兔角膜重度热烧伤(severe corneal thermal burn,SCTB)行穿透性角膜移植术(penetrating keratoplasty,PKP)后角膜新生血管(corneal neovascularization,CNV)及基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)浓度的影响,探讨CXB-SLN对兔SCTB的作用机制。方法取36只新西兰白兔,恒温烧灼器制作兔SCTB模型(左眼),随机分为对照组、PKP组、CXB-PKP组,每组12只。对照组、PKP组球结膜下注射9 g/L的生理盐水0.1 ml,CXB-PKP组球结膜下注射1 g/L的CXB-SLN 0.1 ml。PKP组、CXB-PKP组于造模后第3天行PKP治疗。观察3组白兔术后角膜一般情况并记录术后10、20、40天CNV面积。在术后20、40天各组随机选择6只兔处死。采用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测角膜上清液中MMP-2浓度,并分析CNV面积与MMP-2的相关性。结果术前3组白兔角膜均可见角膜缘充血明显,角膜烧伤区水肿,混浊,伴角膜上皮层坏死、剥脱。术后对照组可见角膜混浊逐渐加重呈瓷白色混浊,PKP组与CXB-PKP组可见角膜植片均成活,角膜透明度尚可。术后10、20、40天,CXB-PKP组CNV面积小于PKP组(P均<0.05),PKP组CNV面积小于对照组(P均<0.05)。术后20和40天角膜上清液MMP-2的浓度,CXB-PKP组低于PKP组,PKP组低于对照组(P均<0.05)。术后20、40天,CNV面积与MMP-2浓度呈正相关(r=0.742,P<0.001;r=0.827,P<0.001)。结论CXB-SLN对兔SCTB后的CNV具有明显抑制作用,可减轻角膜混浊,其机理可能与MMP-2的下调有关,能够为SCTB后行PKP创造有利条件。

角膜移植术后病毒性角膜内皮炎与内皮型排斥反应的临床特征

背景 角膜移植术后由于糖皮质激素类药物和免疫抑制剂的长期使用而导致眼组织的免疫能力下降,从而引起炎性病变,主要表现为术眼角膜内皮炎症反应,常见有病毒性角膜内皮炎和内皮型排斥反应,二者的临床症状相似,但治疗方法和预后有所不同,因此二者的鉴别诊断至关重要,但目前相关研究较少.目的 观察和比较角膜移植术后病毒性角膜内皮炎和内皮型移植排斥反应的临床特征,为临床诊断和治疗提供参考依据.方法 对2011年1月至2013年9月在北京大学眼科中心接受角膜移植术后发生内皮炎症反应的29例患者的病历资料进行回顾性分析,检查项目包括裂隙灯显微镜检查、激光扫描共焦显微镜检查、病毒血清学检测,并采用Goldmann眼压计测量眼压,根据临床症状将患者分为病毒性角膜内皮炎组17例和内皮型排斥反应组12例,分别行抗病毒药物联合糖皮质激素治疗和局部糖皮质激素联合免疫抑制剂治疗,眼压升高者局部用酒石酸溴莫尼定滴眼液和/或马来酸噻吗心安滴眼液点眼,根据二者的临床表现、检查结果和治疗结果总结2种病变的鉴别点.结果 2个组患者接受的术式均为穿透角膜移植术,组间患者术前不同角膜原发病例数的差异有统计学意义（P=0.000）;内皮型排斥反应组患者眼压为（16.00±3.19） mmHg（l mmHg=0.133 kPa）,明显低于病毒性角膜内皮炎组的（34.00±3.84） mmHg,差异有统计学意义（￡=13.298,P=0.000）;内皮型排斥反应组患者术后发病时间为（21.92±8.60）个月,明显长于病毒性角膜内皮炎组的（14.41±5.79）个月,差异有统计学意义（t=-2.816,P=0.009）;内皮型排斥反应组患者平均年龄为（44.00±16.71）岁,明显小于病毒性角膜内皮炎组的（57.24±12.66）岁,差异有统计学意义（t=2.429,P=0.022）.病毒性角膜内皮炎眼角膜后沉着物（KP）呈色素羊脂状,排列散乱,角膜严重水肿,可累及植片和植床,朗格汉斯巨细胞分布无规律,角膜内皮细胞水肿,治疗后多不能恢复;而内皮型排斥反应组角膜后KP排列规律,角膜内皮层洁净,角膜水肿仅累及植片,朗格汉斯巨细胞分布密集且规律,角膜内皮细胞损害轻微,治疗后可恢复正常.2个组间患者血清lgG水平和性别分布的差异均无统计学意义（均P＞0.05）. 结论 角膜移植术后病毒性角膜内皮炎的角膜水肿、KP和炎症反应均重于内皮型排斥反应,且眼压升高主要发生于病毒性角膜内皮炎患者;发病年龄可作为鉴别诊断的重要参考,大于70岁的患者并发病毒性角膜内皮炎的可能性更大;角膜移植术后内皮型排斥反应发生时间晚于病毒性角膜内皮炎,术前角膜原发病对二者的鉴别有重要的参考价值.