Tear Film Stability After Primary Pterygium Excision Combined with Limbal Stem Cell Transplantation is Superior to Amniotic Membrane Transplantation: A Meta-Analysis

Purpose To evaluate the tear film stability after primary pterygium excision combined with Limbal stem cell transplantation (LSCT) or amniotic membrane transplantation (AMT). Methods We searched the PubMed, EMBASE, Web of Science, Cochrane Library, CNKI, Wan Fang and VIP databases for all studies on tear film stability after primary pterygium excision combined with LSCT or AMT. The mean difference (MD) and 95% confidence interval (CI) were calculated for outcomes using the fixed effect or random effect model.Results Seven studies with a total of 531 eyes were enrolled in our meta-analysis, which revealed that comparison between the LSCT group and the AMT group: Ocular Surface Disease Index (OSDI) 3 months postoperatively (MD=-5.16, 95%CI:-6.48,-3.85, P＜0.05), Tear break-up time (BUT) 1 or 3 months postoperatively (1 month: MD=0.30, 95%CI:-0.66,1.26, P=0.54; 3 months: MD=1.30, 95%CI:-0.13,2.72, P=0.07), Schirmer I test 1 or 3 months postoperatively (1 month: MD=0.05, 95%CI:-0.41,0.51, P=0.82; 3 months: MD=1.41, 95%CI:0.81,2.02, P＜0.05), Corneal fluorescein staining (CFS) score 1 month postoperatively (MD=-0.49, 95%CI:-1.29,0.31, P=0.23).Conclusion Primary pterygium excision combined with LSCT is associated with better tear film stability changes than AMT.

Human corneal endothelial cells grafts to replace cadaveric donor corneas

Human corneal endothelial cells (HCEC) grafts to replace cadaveric donor corneas have made tremendous progress in recent years, and this article highlights the most recent discoveries and important achievements in this area. Cell injection therapy with cultured HCEC has just finished its first clinical research, which showed promising results. This follows on the heels of the success of autologous limbal stem cell transplantation in bioengineered ocular tissue transplantation. Transplantation techniques like bioengineered endothelium sheet transplantation and full-thickness corneal transplantation are likely to become more prevalent in the future decade. This goal will be achieved by a combination of current advancements in HCEC propagation, high-quality culture media, and 3D or 4D tissue culture, which will be the trend in the future.

Mini-Review: Regenerating the Corneal Epithelium With Simple Limbal Epithelial Transplantation

Simple limbal epithelial transplantation (SLET) is an ingenious, low cost and effective technique of limbal stem cell transplantation (LSCT) that is increasingly being undertaken in practice across the world. Since it was first described a decade ago, the technique has been performed in a variety of cases of limbal stem cell deficiency (LSCD) and has underwent several innovative modifications. Published literature on SLET has progressively increased over time and successful outcomes in various clinical scenarios have been reported. This concise review attempts to present a crisp account of SLET covering the indications and contraindications of performing the procedure; detailed account of pre-operative work up and preparation; surgical technique and its modifications; post-operative course, care and possible complications as well as published outcomes of surgery from across the world. Comparative analysis of various techniques of LSCT have been discussed and common concerns of surgeons practising or those who are planning to start practising SLET have been addressed. The authors hope that the pragmatic insights and pearls given at the end of the review will aid the surgeons in performing this technique to provide maximum benefit to patients suffering from the potentially blinding condition of LSCD.

Understanding Immune Responses to Surgical Transplant Procedures in Stevens Johnsons Syndrome Patients

Stevens Johnsons syndrome (SJS) is a mucocutaneous disorder caused by an autoimmune response most commonly to medications. Unless it is properly managed in the acute setting, this entity can affect the ocular surface causing chronic cicatrizing conjunctivitis with limbal stem cell deficiency and lid anomalies which ultimately result in corneal opacities that may limit patients' visual acuity. When this stage is reached, some patients might need to undergo some form of corneal and/or limbal stem cell transplantation that exposes an already sensitized immune system to a new alloantigen. While the innate immunity plays a role in corneal graft survival, adaptive immune responses play a major part in corneal graft rejection and failure, namely through CD4+ T cell lymphocytes. Hence, the management of the immune response to surgical transplant procedures in SJS patients, involves a dual approach that modulates the inflammatory response to a new alloantigen in the context of an autoimmune sensitized patient. This review will explore and discuss current perspectives and future directions in the field of ocular immunology on how to manage SJS immune responses to ocular surgical procedures, reviewing systemic and local immunosuppressive therapies and protocols to adequately manage this debilitating condition.

Recent Advances in the Effects of Various Surgical Methods on Tear Film after Pterygium Surgery

Pterygium is a common ocular disorder with a high prevalence. Surgical resection is the main method of treating pterygium. Recurrence rate of traditional surgical methods such as simple excision of pterygium is high. In recent years, amniotic membrane transplantation, autologous limbal stem cell transplantation, application of mitomycin (MMC) and some other methods become commonly used. Autologous limbal stem cell transplantation is being most widely used. Pterygium has a close relationship with dry eye, and dry eye is one of the important reasons for its recurrence. Different surgical methods have different effects on postoperative tear film. This review will summarize the recent points.

Immunocytochemistry of the ocular surface after different techniques of limbal stem cell transplantation for chronic chemical burns

AimTo compare the immunocytochemistry (ICC) on impression cytology of corneal surface epithelium after simple limbal epithelial transplantation (SLET) and conjunctival-limbal autograft (CLAU).MethodsA prospective study of 20 patients above 1 year of age with chronic chemical burns, who underwent limbal stem cell transplantation (LSCT). They were divided equally in group A (SLET) and group B (CLAU). ICC was done for cytokeratin 3 (CK3) and cytokeratin 19 (CK19), preoperatively and postoperatively at 6 months.ResultsFour cases were excluded due to inadequate cellularity in preoperative or postoperative samples. On ICC analysis, in the remaining 16 patients mean CK3 and CK19 positivity changed from 2.06%±1.73% and 83.56%±8.69% preoperatively to 70.62%±13.2% (p<0.0001) and 5.93%±4.17% (p<0.0001), respectively, at 6 months post LSCT. In group A (8 patients) mean CK3 and CK19 positivity of 2%±1.8% and 84.5%±8.4% preoperatively changed to 70%±13.8% (p<0.0001) and 6.25%±5.1% (p<0.0001) at 6 months respectively. While in group B (8 patients), it was 2.12%±1.7% and 82.62%±9.4% preoperatively and 71.25%±013.5% (p<0.0001) and 5.62%±3.2% (p<0.0001) at 6 months. There was no significant difference in expression of CK3 (p=0.084) and CK19 (p=0.744) post SLET or CLAU.Three patients with complete reversion had clear corneas at 6 months.ConclusionReversion of the epithelium to corneal phenotype was documented post LSCT with no difference in expression of CK3 between the two procedures (SLET/CLAU).

TUCK IN CONJUNCTIVALAUTOGRAFTING WITH IN SITU LIMBAL STEM CELL TRANSPLANTATION IN CASE OF RECURRENT PTERYGIUM IN CENTRAL INDIA

AIM: To report outcome and recurrence with Tuck in conjunctival autografting with in situ limbal stem cell transplantation in case of recurrent pterygium in central India where cost is a limiting factor in use of any sutures, Amniotic membrane, Fibrin glue, Mitomycin or Avastin. METHODS: A randomized, non-comparative interventional and prospective clinical study was carried out on 50 patients of recurrent nasal and temporal pterygium at MGM Medical college and Hospital, Jamshedpur from August 2019 to September 2020. Patients with cystic atrophic and Inflamed pterygium, pseudo pterygium, other ocular disorders like Sjogren’s syndrome, blood clotting disorders, glaucoma medication, stents or filtering bleb were excluded from the study. RESULTS: Mean age was32.2 years. Mean follow up was 12.2 months. Outcome measures were cosmetic satisfaction, recurrence rate, graft edema, graft dislocation, graft failure and loss of graft. CONCLUSION: Pterygium being a local limbal stem cell deficiency , its surgical treatment by replenishment of limbal stem cells by tuck in conjunctival autografting with in situ limbal stem cell transplantation is a viable option In cases of recurrent pterygium and is a cheap alternative alleviating need of any sutures, tissue adhesive , antimitotic drugs ,anti VEGFS ,with a lesser intraoperative time, excellent cosmetic result and low recurrence rate.

Long term evaluation of corneal graft survival after lamellar Keratoplasty without limbal stem cell transplantation in patients with delayed-onset mustard gas keratopathy.

Background: Iran is one of the biggest chemical warfare victims in the world and mustard gas keratopathy is a common complication in this rare injury. in recent years, finding an effective and uncomplicated corneal transplantation method has been a concern for ophthalmologists. In this study, we report the results of lamellar Keratoplasty (LK) without limbal stem cell transplantation in patients with delayed-onset mustard gas keratopathy (DMGK). Methods: Thirty-one eyes of 22 veterans with DMGK who underwent conventional LK were included. The presence of limbal stem cell deficiency (LSCD) was proven clinically and so by impression cytology. The results were evaluated with respect to Best spectacle-corrected visual acuity (BSCVA), refractive error (RE), corneal clarity and corneal graft survival rates.Results: The mean age of patients at the time of surgery was 52.93±5.8 years and the mean follow-up duration was 36.25±20.65 months. The mean preoperative BSCVA was 1.67±0.32 logarithm of the minimal angle of resolution unit (Log MAR), which significantly improved and reached 0.32±0.22 Log MAR after surgery. The mean preoperative spherical equivalent RE was 2.47±1.17 diopters which increased to 3.5±1.08 diopters after complete suture removal. Epithelial graft rejection occurred in 9.67% of eyes (3/31) and was treated successfully with topical eye drops. at the end of follow-up period, no signs of graft rejection were found but two eyes had mild central corneal opacity. Conclusions: According to the results of this study, LK without LSC transplantation, can be successful in patients with DMGK, because of partial rather than complete LSCD.