Stromal lenticule addition keratoplasty with corneal crosslinking for corneal ectasia secondary to FS-LASIK:a case series

●AIM:To explore the clinical efficacy and safety of stromal lenticule addition keratoplasty(SLAK)with corneal crosslinking(CXL)on patients with corneal ectasia secondary to femtosecond laser-assisted in situ keratomileusis(FS-LASIK).●METHODS:A series of 5 patients undertaking SLAK with CXL for the treatment of corneal ectasia secondary to FS-LASIK were followed for 4-9mo.The lenticules were collected from patients undertaking small incision lenticule extraction(SMILE)for the correction of myopia.Adding a stromal lenticule was aimed at improving the corneal thickness for the safe application of crosslinking and compensating for the thin cornea to improve its mechanical strength.●RESULTS:All surgeries were conducted successfully with no significant complications.Their best corrected visual acuity(BCVA)ranged from 0.05 to 0.8-2 before surgery.The pre-operational total corneal thickness ranged from 345-404μm and maximum keratometry(Kmax)ranged from 50.8 to 86.3.After the combination surgery,both the corneal keratometry(range 55.9 to 92.8)and total corneal thickness(range 413-482μm)significantly increased.Four out of 5 patients had improvement of corneal biomechanical parameters(reflected by stiffness parameter A1 in Corvis ST).However,3 patients showed decreased BCVA after surgery due to the development of irregular astigmatism and transient haze.Despite the onset of corneal edema right after SLAK,the corneal topography and thickness generally stabilized after 3mo.●CONCLUSION:SLAK with CXL is a potentially beneficial and safe therapy for advanced corneal ectasia.Future work needs to address the poor predictability of corneal refractometry and compare the outcomes of different surgical modes.

Glaucoma drainage device implantation and cyclophotocoagulation in the management of refractory glaucoma after Descemet-stripping automated endothelial keratoplasty

AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.

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.

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.

Two-step strategy—conjunctival flap covering surgery combined with secondary deep anterior lamellar keratoplasty for the treatment of high-risk fungal keratitis

AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK).METHODS:In this noncomparative,retrospective case series,10 subjects(6 males,4 females)with a mean age of 56.5±7.1(range 47-72)y with high-risk FK undergone the two-step strategy were included.Reported outcome measures were healing of the corneal ulcer,recurrence of FK,reject reaction,improvement in best corrected visual acuity(BCVA)and relevant complications.RESULTS:The average diameter of corneal infiltrates was 7.50±0.39 mm,ranging from 6.94 to 8.13 mm.The mean depth of corneal infiltrates was 422.4±77.1μm,ranging from 350 to 535μm.The mean corneal thickness was 597.4±117.3μm,ranging from 458 to 851μm.Hypopyon and endothelial plaques were presented in all patients.The period between the two steps was 3.65±0.9(ranging from 3 to 5)mo.The graft diameter was 7.75±0.39 mm.At the last follow-up(average 9.25±3.39,ranging from 5.5 to 17mo),no fungal recurrence or graft rejection appeared,and all patients showed improvement of BCVA.One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.CONCLUSION:The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK.It is a practical strategy,especially in areas lacking fresh donor corneas and eye bank services.

Indications for and techniques of keratoplasty at Vietnam National Institute of Ophthalmology

AIM： To report the indications for and techniques of corneal transplantation at Vietnam National Institute of Ophthalmology （VNIO） over a period of 12y （2002-2013）, METHODS： Records of patients who had undergone corneal transplantation at VNIO from January 1, 2002 to January 1, 2014 were reviewed to determine the indication for and type of corneal transplant performed. Patient age, gender, indication for corneal transplantation and surgical technique were recorded and analyzed. RESULTS： Corneal transplantation were underwent in 1390 eyes of 1278 patients with a mean age of 44.9±18.1y during the period under review. The most common indication was infectious corneal ulcer （n=670; 48.2%）, followed by corneal scar （n=333, 24.0% ）, corneal dystrophy （n=138, 9.9%） and failed graft （n=112, 8.1%）. Nearly all procedures performed were penetrating keratoplasty （n=1300, 93.5% ）, with a few lamellar keratoplasty procedures performed： lamellar keratoplasty （n=52, 3.7%）, Descemet＇s stripping automated endothelial keratoplasty （n =27, 1.9% ） and deep anterior lamellar keratoplasty （n =11, 0.8%）.CONCLUSION： While the most common indication for keratoplasty was infectious keratitis, nearly all indications for corneal transplantation were managed with penetrating keratoplasty, However, lamellar keratoplasty techniques, including deep anterior lamellar keratoplasty and Descemet＇s stripping automated endothelial keratoplasty, are being performed with increasing frequency for isolated stromal and endothelial disorders, respectively,

Destructive effects on endothelial cells of grafts in cytomegalovirus DNA-positive patients after keratoplasty

AIM:To investigate corneal graft survival rate and endothelial cell density(ECD)loss after keratoplasty in cytomegalovirus(CMV)positive patients.METHODS:This was a retrospective cohort study.We analyzed the clinical data of patients who underwent viral DNA detection in aqueous humor/corneal tissue collected during keratoplasty from March 2015 to December 2018 at the Peking University Third Hospital,Beijing,China.To further evaluate the effect of CMV on graft survival rate and ECD loss,patients were divided into three groups:1)CMV DNA positive(CMV+)group;2)viral DNA negative(virus-)group,comprising virus-group eyes pairwise matched to eyes in the CMV+group according to ocular comorbidities;3)control group,comprising virus-group eyes without ocular comorbidities.The follow-up indicators including graft survival rate,ECD,ECD loss,and central corneal thickness(CCT),were analyzed by Tukey honestly significant difference(HSD)test.RESULTS:Each group included 29 cases.The graft survival rate in CMV+group were lowest among the three groups(P=0.000).No significant difference in donor graft ECD was found among three groups(P=0.54).ECD in the CMV+group was lower than the virus-group at 12(P=0.009),and 24mo(P=0.002)after keratoplasties.Furthermore,ECD loss was higher in the CMV+group than in the virus-group in the middle stage(6-12mo)postkeratoplasty(P=0.017),and significantly higher in the early stage(0-6mo)in the virus-group than in the control group(P=0.000).CONCLUSION:CMV reduces the graft survival rate and exerts persistent detrimental effects on the ECD after keratoplasty.The graft ECD loss associate with CMV infection mainly occurrs in the middle stage(6-12mo postoperatively),while ocular comorbidities mainly affects ECD in the early stage(0-6mo postoperatively).

Changes in endothelial cell density following penetrating keratoplasty and deep anterior lamellar keratoplasty

· AIM: To compare the corneal endothelial cell density (ECD) of clear grafts after penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK). · METHODS: The study included 44 and 54 patients treated with PK and DALK, respectively, between March 2006 and April 2010. Corneal ECD was examined using specular microscopy at postoperative 1, 3, 6, 12, and 18 months, and the values were compared. · RESULTS: Corneal ECD reduction in the PK group was 7.4%, 15.2%, 23.5%, and 28.9% at 3, 6, 12 and 18 months respectively after surgery, compared with 4.2 % in the first month (P <0.01). These figures were 3.0%, 6.7%, 7.2%, and 7.7% at 3, 6, 12 and 18 months respectively, compared with 2.2 % in the first month in the DALK group (P >0.05). · CONCLUSION: Compared with DALK,PK significantly reduced ECD of the clear grafts. These results suggest that survival of endothelial cells in grafts is better after DALK than after PK. ·

Clinical results of non-Descemet stripping endothelial keratoplasty

AIM： To investigate the impact of non-Descemet stripping endothelial keratoplasty（non-DSEK） on graft rejection rate,and its overall procedural effectiveness in patients.METHODS： Non-DSEK was performed on 65 eyes of 64 patients,and the procedural outcomes,including rejection episodes,failure and dislocation of the grafts,best corrected visual acuity（BCVA）,endothelial cell density（ECD）,and other complications,were analyzed retrospectively.RESULTS： Of the 65 eyes,63 recovered from bullous keratopathy with a clear cornea.The mean follow-up time was 26.4mo（range,6-84mo）.The mean BCVA improved from 1.70 log MAR preoperatively to 0.54 log MAR at 3mo,0.46 logM AR at 6mo,and 0.37 logM AR at 1y after surgery.The postoperative donor ECD of the 25 patients who successfully underwent specular microscopic examination was 1918±534 cells/mm^2（range,637 to 3056 cells/mm^2）,and the mean endothelial cell loss was 41.9% at 24 mo postoperatively.One eye developed secondary glaucoma and required regrafting via penetrating keratoplasty（PKP）.Another eye had postoperative graft failure due to rejection at 26 mo.Postoperative graft dislocation occurred in eight eyes.All of the eight dislocated grafts were reattached using air reinjection.CONCLUSION： Immunological graft rejection of the donor graft rarely occurs in non-DSEK.Therefore,non-DSEK is a safe,concise,and effective alternative to restore corneal decompensation when the Descemet membrane is disease-free.

Indications for penetrating keratoplasty and anterior lamellar keratoplasty during 2010-2017

AIM: To review the indications of penetrating keratoplasty(PK) and anterior lamellar keratoplasty(ALK) at Qingdao Eye Hospital, Shandong Eye Institute, Qingdao, China, from 2010 to 2017. METHODS: The data of all patients undergoing PK or ALK from January 2010 to December 2017 was retrospectively reviewed, with the indications during 2010-2013 and 2014-2017 compared. RESULTS: A total of 1869 eyes were included, among which 1405 eyes(75.2%) had PK and 464 eyes(24.8%) had ALK. The leading indications were suppurative keratitis(36.8%), keratoconus(15.5%), herpes keratitis(13.1%), and regraft(10.5%). In eyes undergoing PK, the top four indications were suppurative keratitis(38.7%), herpes keratitis(15.3%), keratoconus(12.6%), and regraft(12.5%) during 2014-2017, with the proportion of suppurative keratitis and herpes keratitis decreased while regraft and keratoconus increased compared with 2010-2013. In eyes with ALK, suppurative keratitis(30.8%), keratoconus(24.1%), corneal dystrophies and degenerations(10.6%), and corneal dermoid tumor(9.7%) were the top four indications, and there was no significant difference for the proportion of each indication between 2010-2013 and 2014-2017. CONCLUSION: Suppurative keratitis is the most common indication for PK and ALK at Qingdao Eye Hospital during 2010-2017, followed by keratoconus, herpes keratitis, and regraft. In eyes treated with PK, the proportion of suppurative keratitis and herpes keratitis decrease while regraft and keratoconus increase during 2014-2017 compared with 2010-2013.

Lamellar keratoplasty with corneoscleral graft for limbal dermoids

To assess the postoperative outcomes of limbal dermoid excision with corneoscleral graft transplantation. The charts of 8 consecutive patients （mean age： 13.0y） who had undergone limbal dermoid excision with lamellar corneosclerai graft transplantation by a single surgeon were retrospectively reviewed. Mean dermoid size was 7.75 mm （6.0-12.0 mm）. Mean visual acuities （in IogMAR units） before and after surgery were 1.8 and 1.7, respectively （P=0.29）. Spherical equivalents were 1.3 diopter （D） before surgery and 0.7 D after surgery （P=0.40）. The mean astigmatism measurements before and after surgery were 2.4 D and 1.5 D, respectively （P=0.17）. Vector analysis revealed a mild change in astigmatism with a mean ＂d＂ of 3,2 （0,56-6.89）, No intra- or post-operative complications occurred. Lamellar keratoplasty for limbal dermoids is safe and offers good cosmesis and tectonic stability. A significant decrease in the amount of astigmatism is not expected following surgery.

Femtosecond Laser-Assisted Refractive Autokeratoplasty: A Pilot Study

Purpose: To develop a new method of femtosecond laser-assisted refractive autokeratoplasty (FRAK) in advanced keratoconus and to evaluate preliminarily early clinical results. Methods: A total of 17 patients with stable advanced keratoconus and a mean age of 33 ± 8.4 years were included in the study. FRAK was performed in all cases with the IntraLase 60 kHz (Abbott Medical Optics Inc.). A 2-step resection of corneal stroma was performed using the femtosecond laser, with the generation of a circular corneal flap with wedge-shaped profile. After flap removal, the corneal wound was sutured. Results: The surgical procedure and early postoperative period were uneventful in all cases. Mean uncorrected distance visual acuity (UDVA) improved significantly from 0.07 ± 0.03 preoperatively to 0.26 ± 0.13 at 3 months after surgery. Improvement in corrected distance visual acuity (CDVA) was observed in 94.1% of cases, with 76.5% of eyes showing an improvement of more than 3 lines. Between 3 and 6 months after surgery, an additional improvement was observed in UDVA and CDVA. Corneal cylinder decreased significantly from 9.1 ± 3.8 D preoperatively to 4.4 ± 2.75 D at 6 months postoperatively. Conclusions: FRAK may be an alternative treatment in stable advanced keratoconus, allowing a significant visual improvement and corneal regularization while saving the patient's own corneal tissue. The non-penetrating nature of the surgical technique helps to minimize the risks associated to this type of surgery. Further research is needed to determine the functional long-term outcomes.

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.

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-LASIK keratectasia.·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 2had 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.

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.

Trends in the indications for penetrating keratoplasty in Shandong,2005-2010

AIM: To identify the current indications and the trend shifts for penetrating keraboplasty (PKP) in Shandong. METHODS: The medical charts of all patients who underwent PKP at Shandong Eye Institute from June 1, 2005 to May 31, 2010 were analysed retrospectively. RESULTS: A total of 875 patients (875 eyes) received PKP in this 5-year period, accounting for 61.6% of all corneal transplantation surgeries. The leading indications for PKP were infectious keratitis (37.1%), HSK (19.1%), keratoconus (11.2%), bullous keratopathy (8.5%), regrafting (6.7%) and corneal scarring (4.8%). The percentage of PKP for keratoconus declined year by year, whereas the percentage of bullous keratopathy had a mild annual increase. Fungal infections accounted for 65.2% of the infectious keratitis cases, remaining the leading cause of corneal infection. In addition, 54.1% of bullous keratopathy cases were associated with cataract surgery. The leading initial diagnoses associated with regrafting were infectious keratitis (38.9%), HSK (18.6%) and corneal burn (16.9%). The major causes of regrafting included graft endothelial dysfunction (39.0%), graft ulcer (28.8%) and primary disease recurrence (15.3%). CONCLUSION: Infectious keratitis remained the leading indication for PKP in Shandong, and fungal infections were still the major cause of corneal infections. There was an increasing trend in the percentage of PKP cases indicated for bullous keratopathy but a decline in the same for keratoconus. Even with a decline in the overall proportion among all corneal transplantation surgeries, PKP is still the major corneal transplant choice in Shandong.

Long-term outcomes of penetrating keratoplasty in keratoconus: analysis of the factors associated with final visual acuities

AIM:To investigate the long-term results of penetrating keratoplasty(PK)in patients with keratoconus(KC)and to evaluate factors that might influence the final visual outcome.METHODS:We retrospectively reviewed the data of all patients with clinical KC who had undergone PK by a single corneal surgeon in a single center from May 1980to December 2005.The age of the patients,preoperative best-corrected visual acuity(BCVA),corneal thickness,death to preservation time,and preservation to transplantation time were recorded.Additionally,postoperative complications such as graft rejection,development of glaucoma and specular microscopy were checked during the follow-up.RESULTS:Sixty-nineeyesfrom69patientswerefinally included.The follow-up period was 8.64±6.13y.Graft rejection occurred in 4 eyes of 69 cases(5.8%),and the time to graft rejection was 2.1±1.3y.A Kaplan-Meier survival analysis showed that the estimated cumulative probability of graft rejection at 6,13,and 17y after PK were 95.6%,90.0%,and 78.8%,respectively.When we evaluated factors that might influence final BCVA in eyes,no disparity donor-host trephine size(same graft size)as well as higher spherical equivalent,and average Kvalue were associated with higher final BCVA.(P=0.006,0.051,0.092,and 0.021 in eyes with follow-up【8y;P=0.068,0.065,and 0.030 in eyes with follow-up≥8y,respectively).CONCLUSION:The long-term results of PK in patients with KC were favorable with a high percentage of good BCVA.Less myopic change and low average K-reading,as well as a surgical technique using the same size donor-recipient button may provide better visual outcomes particularly in patients with KC.

Visual acuity and endothelial cell density with respect to the graft thickness in Descemet's stripping automated endothelial keratoplasty: one year results

AIM: To evaluate the visual acuity and endothelial cell density according to the thickness in Descemet’s stripping automated endothelial keratoplasty(DSAEK)one year after surgery.METHODS: DSAEK patients’ data were reviewed. Thirty seven eyes of 37 patients who underwent DSAEK for pseudophakic bullous keratopathy(PBK) were included in this study. Graft thickness was measured with optical coherence tomography(OCT) 12 mo after DSAEK. Eyes were divided into 3 groups based on the graft thickness:thick(】200 μm), medium-thick(150-200 μm) and thin(【150 μm). Best corrected visual acuity(BCVA),endothelial cells density(ECD) and complications were assessed and comparisons were done between groups.RESULTS: Median thickness of postoperative grafts was 188(range 73-317 μm). There was no significant difference in age, sex, preoperative BCVA, or follow-up period between DSAEK groups. At postoperative 12 mo,mean BCVA was 0.28±0.10 in thick graft group, 0.52±0.08 in medium-thick graft group, and 0.72 ±0.06 in thin graft group. Thin grafts showed better postoperative BCVA as compared with the medium-thick and thick grafts(P =0.001). Thick graft group had 1637.44 ±88.19-mm2,medium thick graft had 1764.50±34.28-mm2 and thin graft group had 1845.30 ±65.62-mm2. Thin graft group had better ECD at 12 mo after surgery(P =0.001).CONCLUSION: Thin grafts after DSAEK ensure better visual rehabilitation. Eyes with thin grafts had significantly lesser loss of ECD compared to eyes withmedium-thick and thick grafts one year after surgery.

Central corneal epithelium self-healing after ring-shaped glycerin-cryopreserved lamellar keratoplasty in Terrien marginal degeneration

Dear Sir, I am Dr Yan-Long Bi, from the Department of Ophthalmology, Tongji University Affiliated to Tongji University School of Medicine, Shanghai, China. I write to present a case report of total limbal stem cells deficiency after treatment with ring-shaped lamellar keratoplasty secondary to Terrien marginal degeneration. During 3 years

Comparison of long-term results after manual and femtosecond assisted corneal trephination in deep anterior lamellar keratoplasty for keratoconus

AIM: To compare long-term postoperative outcomes of manual and femtosecond assisted corneal trephination in deep anterior lamellar keratoplasty(FS-DALK) for keratoconus.METHODS: In the retrospective study, 17 consecutive eyes that underwent vertical side cut incision FS-DALK and 22 eyes that underwent trephine incision DALK were collected over a 2-year period. Main measurements included postoperative uncorrected-visual acuity(UCVA), corrected distance visual acuity(CDVA), refractive sphere and cylinder, manifest refraction spherical equivalent(MRSE), flat and steep corneal keratometry(K1 and K2), endothelial cell density(ECD), and time of epithelium healing and suture removal.RESULTS: Groups were comparable for diagnosis and preoperative visual acuity. Follow-up averaged 23 mo(range, 12-36 mo). At 12 mo, the mean UCVA was better in the manual-DALK group(P=0.039), and the refractive sphere was lower in the FS-DALK group(P=0.040). MRSE between groups differed at 1, 6, and 12 mo postoperatively(P=0.047, 0.025, 0.042, respectively). Mean CDVA, cylinder, K1, K2,corneal astigmatism, ECD, and time of epithelium healing were similar between groups. Stability of MRSE, ECD, and K1 returned sooner after FS-DALK. Initial loosened suture removal time was earlier in the manual-DALK group(P=0.042) while complete suture removal time was similar(P=0.122).CONCLUSION: Manual and femtosecond assisted corneal trephination in DALK are options for advanced keratoconus. FS-DALK do not result in improved visual acuity but it is more stable during the follow-up period. FSDALK in the present form show limited benefit, so surgical design and parameters still need to be optimized and explored.