Tenon's Tissue Research Articles

Hybrid technique of tuck-in Tenon's patch graft and tissue adhesives and bandage contact lens (TABCL) for large corneal perforation in microbial keratitis.

We describe the hybrid technique of tuck-in Tenon's patch graft (TPG) and tissue adhesive bandaged contact lens (TABCL) for large corneal perforations (>5 mm) with intact surrounding stroma. Management of large corneal perforation is often challenging, and urgent availability of donor cornea might be difficult; Tenon patch alone does not provide tectonic support; hence, this hybrid technique can be used safely in large perforations. This involves freshening the perforation edges, creating a 3600 stromal pocket, harvesting a Tenon's graft 1 mm oversized, tucking into the pocket, and suturing. Then areas of leakage were noted, and only those areas were supplemented with minimal cyanoacrylate glue (CG) at the graft edges. This technique was used in two eyes, one with a large corneal perforation and intact surrounding stroma and the other with 4 mm corneal fistula post healed keratitis with a failed primary TPG alone, and led to epithelialization and a smooth corneal surface at 6 weeks. The advantages include autologous tissue, cost-effective, easily available, minimal post-operative inflammation, vascularization, and surface irregularity.

Penetrating keratoplasty following Tenon's patch graft

This report aims to describe the histopathological changes in the cornea following Tenon's patch graft. A 51-year-old male underwent Tenon's patch graft (TPG) for corneal perforation following Therapeutic penetrating keratoplasty which was performed twice for non-resolving microbial keratitis and graft infiltrate, respectively. The infection resolved following TPG resulting in formation of a vascularised scar. An Optical penetrating keratoplasty was performed six months after the TPG. Postoperative period was uneventful. Histo-pathological evaluation of the excised corneal tissue revealed excellent integration of the tenon tissue with the surrounding corneal stromal collagen. Histo-pathological evidence suggests that, tenon's tissue integrates well with surrounding corneal stromal collagen and is probably capable of regenerating new collagen and thus aid in corneal wound healing

Cytokines Associated With Onset of a Hypertensive Phase and Surgical Failure After Ahmed Glaucoma Valve Implantation

To investigate the relationship between cytokines of the aqueous humor or Tenon capsule, the onset of a hypertensive phase, and surgical failure in patients undergoing Ahmed Glaucoma Valve (AGV) implantation DESIGN: Prospective clinical cohort study. A total of 36 patients who underwent AGV implantation were included. Samples of aqueous humor and Tenon tissue were collected at the time of surgery. Multiple cytokines were evaluated in the samples using a bead-based multiplex cytokine assay. As for surgical outcomes, a hypertensive phase was defined as an intraocular pressure (IOP) of greater than 21 mm Hg within 3 months after surgery, whereas surgical failure was defined as an IOP greater than 21 mm Hg with maximum tolerable glaucoma medications during 2 consecutive visits. Patients who entered a hypertensive phase showed higher transforming growth factor-β2 (TGF-β2) levels in the aqueous humor (P=.012). A longer axial length and higher TGF-β2 concentration of the aqueous humor were associated with higher maximum IOP values during 3 months after surgery per multiple regression analysis (P=.028 and P=.034). In the multiple logistic regression analysis, higher monocyte chemoattractant protein-1 (MCP-1) concentrations in the aqueous humor and higher interleukin-4 concentrations in Tenon tissue were related to surgical failure (P=.022 and P=.040). Greater concentrations of TGF-β2 and MCP-1 were related to surgical outcome after glaucoma drainage device implantation. Further studies are needed to confirm that down-regulation of these cytokines could be helpful in improving surgical outcomes.

A model for designing intraocular pressure-regulating glaucoma implants.

Glaucoma is a group of eye conditions that damage the optic nerve, the health of which is vital for vision. The key risk factor for the development and progression of this disease is increased intraocular pressure (IOP). Implantable glaucoma drainage devices have been developed to divert aqueous humor from the glaucomatous eye as a means of reducing IOP. The artificial drainage pathway created by these devices drives the fluid into a filtering bleb. The long-term success of filtration surgery is dictated by the proper functioning of the bleb and overlying Tenon's and conjunctival tissue. To better understand the influence of the health condition of these tissues on IOP, we have developed a mathematical model of fluid production in the eye, its removal from the anterior chamber by a particular glaucoma implant-the PRESERFLO® MicroShunt-, drainage into the bleb and absorption by the subconjunctival vasculature. The mathematical model was numerically solved by commercial FEM package COMSOL. Our numerical results of IOP for different postoperative conditions are consistent with the available evidence on IOP outcomes after the implantation of this device. To obtain insight into the adjustments in the implant's hydrodynamic resistance that are required for IOP control when hypotony or bleb scarring due to tissue fibrosis take place, we have simulated the flow through a microshunt with an adjustable lumen diameter. Our findings show that increasing the hydrodynamic resistance of the microshunt by reducing the lumen diameter, can effectively help to prevent hypotony. However, decreasing the hydrodynamic resistance of the implant will not sufficiently decrease the IOP to acceptable levels when the bleb is encapsulated due to tissue fibrosis. Therefore, to effectively reduce IOP, the adjustable glaucoma implant should be combined with a means of reducing fibrosis. The results reported herein may provide guidelines to support the design of future glaucoma implants with adjustable hydrodynamic resistances.

The Efficacy of Atelocollagen to Inhibit Fibrotic Proliferation in Tenon Tissue: In vitro Study

Introduction: The aim of the study was to evaluate the safety and efficacy of atelocollagen in preventing the fibrotic change of human tenon tissue induced by transforming growth factor β1 (TGFβ1). Methods: Primary cultured human Tenon’s fibroblasts (HTFs) were incubated with TGFβ1 alone and with various concentrations of atelocollagen, respectively. Cell viability was measured by Cell Counting Kit-8 (CCK-8). The mRNA levels of α-smooth muscle actin (α-SMA), vimentin, fibronectin, zonular occludens scaffolding protein (ZO-1), cellular communication network factor 2 (CCN2), and interleukin 6 (IL-6) were measured by quantitative reverse transcription polymerase chain reaction, Western blot, and immunofluorescence analysis. Wound healing assay and collagen contraction assay were additionally evaluated for identifying the inhibitory effect of atelocollagen in HTFs. To elucidate the mechanism by which atelocollagen affects HTF proliferation, the phospho-extracellular-signal-regulated kinases (pERK)/total-extracellular-signal-regulated kinases (tERK), phospho-focal adhesion kinase (pFAK)/total-focal adhesion kinase (tFAK), and pSmad3/tSmad3 protein expression ratios were measured by Western blot. Results: The safety of atelocollagen in HTF was identified by CCK-8 analysis. The expression of α-SMA and vimentin in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased at both mRNA and protein levels, while that of ZO-1 in 0.046% atelocollagen increased compared with TGFβ1-treated cells. The protein expression of fibronectin, CCN2, and IL-6 in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased. The immunofluorescence microscopy of α-SMA and ZO-1 showed results similar to those of the Western blot. In the wound-scratch assays, cell migration was significantly attenuated in HTFs treated with 0.005% atelocollagen. Atelocollagen at 0.005, 0.011, and 0.023% significantly inhibited the gel contraction induced by TGFβ1 at both 24 h and 48 h. The increase in pERK/tERK and pSmad3/tSmad3 protein expression ratios in TGFβ1-treated HTFs significantly decreased after treatment with 0.023 and 0.046% atelocollagen. Conclusion: Since atelocollagen gel effectively suppresses the proliferation of HTFs in TGFβ1-induced transdifferentiation, it may be a potential therapeutic agent in glaucoma surgery.

Tectonic Tenon transplants for four different corneal melts

Tenon's tissue with good tensile strength, pliability, and availability is a valuable patch graft resource for small corneal perforations. We have extended its tectonic use to other corneal melts and leaks with anatomic success. Tenon's patch graft (TPG) was employed for tissue building in four different corneal melts: Mooren's ulcer, leaking cicatrix, persistent epithelial defect, and perforation. The minimum follow-up was six months. TPG is less resource-intensive and longer lasting than cyanoacrylate glue and multilayered-amniotic grafts. It is safe, providing good tectonic outcomes not only in corneal perforations but also in melts secondary to infective, immune, and toxic causes.

The Effect of Irradiated Riboflavin in Human Tenon’s Fibroblast – A Study on Cellular Viability

ABSTRACT Purpose/ Aim The main purpose of this work is to study the cellular viability effect of irradiated riboflavin in cultured human tenon fibroblasts. Materials and Methods The tenon tissue was harvested from a patient undergoing strabismus surgery. The human tenon fibroblast cell culture and isolation were performed according to the standard laboratory cell culturing protocol. The cells were divided into three groups: control, treatment with irradiated and non-irradiated riboflavin. There were five different concentrations (0.00156%, 0.003125%, 0.00625%, 0.0125%, 0.025%) in each group of riboflavin. The fibroblasts were treated with riboflavin and the cellular viability was assessed at 24-hour and 48-hour post treatment with MTT 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide colorimetric assay. The absorbance values were analysed using Magellan microplate reader data analysis. A triplicate of readings was taken. The data were presented as mean ± standard deviation of the triplicates. Statistical analysis was performed with Statistical Package for Social Sciences (SPSS) analysis version 23. Results Irradiated riboflavin caused a concentration-dependent cell death in human tenon fibroblast cell culture (p < .05). The antiproliferative difference between irradiated and non-irradiated riboflavin was significant up to 48 hours (p < .05). Post hoc multiple comparisons showed higher concentrations of irradiated riboflavin (0.0125% and 0.025%) caused more reduction in cellular viability in human tenon fibroblast cells (p < .05). The duration of treatment is not a causative factor in this study. Conclusions This pilot experiment demonstrated that irradiated riboflavin induced cell death in human tenon fibroblast culture in a concentration-dependent manner, but is not time-dependent. Further exploratory investigations should be performed to determine the mechanism of cell death. We postulate that apoptosis occurred in these irradiated riboflavin-treated cells.

The Effect of CHIR 99021, a Glycogen Synthase Kinase-3β Inhibitor, on Transforming Growth Factor β-Induced Tenon Fibrosis.

PurposeThis study investigated the effect of glycogen synthase kinase-3β (GSK-3β) inhibition on the fibrosis of human Tenon's fibroblasts (HTFs) induced by transforming growth factor-β (TGF-β).MethodsQuantitative real-time PCR and Western blot analyses were performed to determine the expression levels of molecules associated with the fibrosis of HTFs by TGF-β (fibronectin, collagen Iα, and α-smooth muscle actin) and GSK-3β. The levels of phosphorylated Smad2 and Smad3 were also analyzed in the presence of the GSK-3β inhibitor CHIR 99021. The wound healing assay was performed to determine the effect of CHIR 99021 on the migration of HTFs. All experiments were conducted using primary cultured HTFs or human tenon tissues obtained from normal subjects and patients with glaucoma.ResultsTreatment with TGF-β resulted in an increase in the levels of molecules associated with the fibrosis of HTFs. The expression levels of these molecules were higher in the tenon tissues obtained from patients with glaucoma than those from normal subjects. When the HTFs were treated with TGF-β, a significant increase in the active form of GSK-3β (Y216) was observed. A significant decrease in the active form of GSK-3β and molecules associated with fibrosis by TGF-β was noted in HTFs treated with CHIR 99021. CHIR 99021 treatment reduced the phosphorylated Smad2/Smad2 and phosphorylated Smad3/Smad3 ratios in HTFs and attenuated HTF migration.ConclusionsOur results demonstrated the effect of GSK-3β inhibition on the regulation of TGF-β–mediated fibrosis of HTFs, suggesting GSK-3β to be a potential target for maintaining bleb function after glaucoma filtration surgery.

Recurrent Pterygium: A Review.

Purpose:To summarize the recent evidence regarding different aspects of pterygium recurrence.Methods:Human-based studies from PubMed, Scopus, and Google Scholar were identified using the following keywords: conjunctival disease, pterygium, recurrent pterygium, pterygium recurrence, pterygium management/surgery, conjunctival autograft (CAU), amniotic membrane graft/transplant, and adjuvant therapy (January 2009 to February 2021). We reviewed risk factors associated with the recurrence of pterygium, timing of recurrence, medical treatments to prevent from recurrence, and nonsurgical and surgical alternatives for management of recurrence.Results:Dry eye disease, black race, and young age are considered definite risk factors for recurrence. However, fleshy appearance of the pterygium and preoperative size remain controversial. Surgical techniques such as excessive suturing, insufficient conjunctival graft size, thick conjunctival graft with remained Tenon tissue, and postoperative graft retraction are considered possible risk factors for recurrence. Using fibrin glue instead of sutures can further reduce recurrence rates. Although recurrence could occur even after many years, most recurrences happen in the first 3–6 months after surgery. Multiple kinds of adjuvant medications are used before, during, or after the operation including mitomycin C (MMC), 5-fluorouracil (5-FU), corticosteroids, and anti-vascular endothelial growth factors (anti-VEGFs). Multiple weekly subconjunctival 5-FU injections are shown to be safe and effective in halting the progression of recurrent pterygium. Although topical bevacizumab is found to inhibit the growth of impending recurrent pterygium, the effect is mostly temporary. CAU is superior to amniotic membrane transplantation in the treatment for recurrent pterygia.Conclusions:There is yet to be a panacea in treating recurrent pterygium. Currently, there is not a globally accepted recommendation for treating recurrent pterygium with anti-VEGFs or 5-FU as a nonsurgical treatment. We strongly recommend using MMC as an adjunct to surgery in recurrent cases, with consideration of its specific complications. CAU is the most effective surgical treatment for recurrent pterygium, and other new surgical therapies need further investigation.

Tuck-in tenon's patch graft for corneal perforation

Corneal perforation remains to be one of the most dreaded complications of ocular trauma and its prompt diagnosis and management is key to quick recovery. Tuck-in Tenon's patch graft is an extremely viable and handy technique to tackle corneal perforation. The tenon's tissue, being autologous, reduces the chance of rejection while providing good tectonic support. This is a case series of tuck-in Tenon's patch graft done for cases of corneal perforation. Through the case series, we try to put forth our experience with this novel technique.

SPARC Levels Modulate the Capacity of Mitomycin to Inhibit the Proliferation of Human Tenon's Capsule Fibroblasts.

Purpose To evaluate the role of SPARC in the antiproliferation effect of MMC on human Tenon's fibroblasts (HTF). Method Sixteen PACG patients aged 59 ± 10 years (31–72 years), including 6 males and 10 females, were recruited. Tenon tissue was harvested during filtering surgery. Cell density was evaluated after MMC application with different concentrations and application times, by which the optimized MMC application modality was determined. MMC, si-SPARC, or SPARC protein was used when needed to evaluate the cell densities under different conditions, by which the role of SPARC in MMC-mediated antifibrotic process was identified. Results Considering that the cell densities, as well as SPARC expression on mRNA and protein levels, are relatively stable when the MMC concentration is higher than 0.02% and exposure time longer than 90 s, we chose the MMC application pattern with 0.02% and 90 s as an optimized pattern for the downstream work. Compared to control, the si-SPARC and MMC downregulated the SPARC protein by 91% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (P < 0.01) and 65% (Conclusion This study demonstrates that in HTF, (1) MMC downregulates the expression of SPARC in protein and mRNA levels; (2) SPARC depletion has synergistic effect on the antifibrotic effect of MMC; and (3) reactive oxygen species are the possible mediator in the antifibrotic effect of MMC and si-SPARC.

Prevention of Ocular Tenon Adhesion to Sclera by a PDMAA Polymer to Improve Results after Glaucoma Surgery.

The authors describe a process that may eventually reduce the risk of scar formation after glaucoma surgery. For this, a thin hydrogel coating is photochemically generated and linked to the sclera surface at the surgical site. This coating is generated from a photoreactive prepolymer containing anthraquinone groups, which is administered as a thin pad to the sclera surface. Short UV irradiation leads to a reaction of the photogroups with neighboring chains via C-H insertion crosslinking, thus transforming the precursor polymer into a hydrogel. Simultaneously, a reaction between the photogroups and the underlying sclera tissue occurs, so that the hydrogel patch becomes covalently linked to the tissue. The authors show that the resulting thin coating is strongly cell repellent and hinders tenon fibroblasts to form tenon tissue at the site of the coating and is suitable for inclusion into a surgical procedure.

Lowered Decorin With Aberrant Extracellular Matrix Remodeling in Aqueous Humor and Tenon's Tissue From Primary Glaucoma Patients.

To evaluate the inflammatory cytokine, growth factors, extracellular matrix (ECM) remodeling genes, profibrotic and antifibrotic molecules in patients undergoing glaucoma filtration surgery (GFS). Additionally, the effect of preoperative antiglaucoma medications (AGMs) and postoperative bleb status were related to these parameters. Tenon's tissue and aqueous humour (AH) were collected from 207 patients undergoing GFS with primary open-angle glaucoma (POAG) (n = 77), primary angle-closure glaucoma (PACG) (n = 62), and cataract controls (n = 68). Monocyte chemoattractant protein-1 (MCP-1), connective tissue growth factor (CTGF), transforming growth factor β1/2 (TGF-β1/2), lysyl oxidase (LOX), lysyl oxidase L2 (LOXL2), elastin (ELN), collagen type 1 α 1 (COL1A1), secreted protein acidic and rich in cysteine (SPARC), α-smooth muscle actin (α-SMA), and decorin (DCN) were determined in tenon's tissue by real-time PCR and in AH using ELISA. A significant increase was observed in the transcripts of MCP-1, TGF-β2, and SPARC in POAG and PACG (P < 0.05); CTGF, TGF-β1, LOX, LOXL2, ELN, COL1A1, and α-SMA in PACG (P < 0.05) compared with control. DCN transcript was significantly decreased in POAG and PACG (P < 0.05) compared with control. The protein levels of CTGF, TGF-β1/β2, ELN, SPARC, and LOXL2 was significantly elevated in POAG and PACG (P < 0.05); DCN was decreased (P < 0.05) compared with control. These parameters showed significant association with duration of preoperative AGMs and postoperative bleb status. This study demonstrates increased expression of growth factors and ECM molecules, both at protein and transcript levels in GFS patients. A decreased DCN in AH seems striking, and if restored might have a therapeutic role in minimizing postoperative scarring to improve GFS outcome.

Involvement of ER Stress in Human Primary Pterygium

Purpose: The aim of this study was to investigate the ER stress activation in human primary pterygium. Methods and materials: Human primary pterygium or normal Tenon's capsule tissues were obtained from patients with primary pterygium following surgical excision or from normal human fresh cadaver eyes. The tissues were processed within 2 hours. The mRNA or protein specimens were extracted from those tissues for analysis, cryosections of those tissues were prepared for immunohistochemical staining. The mRNA levels of endoplasmic reticulum (ER) stress-related factors in those tissues were detected by qPCR analysis and the related proteins levels were detected by qPCR analysis and immunohistochemical staining or western blotting. Results: The ER stress-related gene transcription levels of GRP78，spliced XBP-1, ATF4 and ATF6 and the protein expression levels of GRP78, p-IRE1α, p-eIF2α and ATF6 were all increased in the human primary pterygium tissues when compared with the normal control tissues. Conclusion: The results in this study suggest that the three unfolded protein response pathways are all activated in the human primary pterygium tissues, which indicates that the ER stress is involved in the progression of pterygium, and also suggests a potential mechanism of ER stress-induced inflammation in the human primary pterygium tissues.

Expression of p53 and its effect on microRNA-29b expression in the process of normal human conjunctival fibroblasts transforming to myofibroblast

Objective To investigate the relationship between p53 and miR-29b in myofibroblasts (MFs) induced from human Tenon fibroblasts (HTFs). Methods Human Tenon tissues were obtained from strabismus surgery patients in the First Affiliated Hospital of Anhui Medical University from March to July 2016.The primary HTFs were cultured by tissue culture method and passaged to 2-4 generations.The cells were divided into 4 groups: HTFs group cells were normally cultured, the TGF-β1 activation group cells was activated with 10 ng/ml tumor necrosis factorβ1(TGF-β1), the siRNA transfection group and the negative control group were transfected with p53 siRNA and negative siRNA, respectively.The expression of p53 protein and cell migration ability of HTFs and MFs were detected by immunohistochemical and cell scratch assay.The relative expression level of miR-29b and p53 mRNA in each group was detected by real-time PCR.This study followed the Helsinki declaration and the patients or their guardians signed informed consent. Results The primary HTFs had long fusiform shape, and were arranged in a spiral shape.After activated by TGF-β1, the cells were transformed into MFs, and the cell morphology was irregular and the arrangement was disordered.The staining intensity of p53 protein in TGF-β1 activation group was significantly stronger than that in HTFs group(t=-10.384, P<0.05). The migration distance of TGF-β1 activation group cells was significantly larger than that of HTFs group (P<0.05). The relative expression level of p53 mRNA was 1.00±0.00, 3.95±2.61, 0.06±0.06 and 0.98±0.16 in HTFs group, TGF-β1 activation group, siRNA transfection group and negative control group, respectively; the relative expression levels of miR-29b was 1.00±0.00, 0.54±0.09, 5.10±2.31 and 1.03±0.09 in HTFs group, TGF-β1 activation group, siRNA transfection group and negative control group, respectively; the overall differences were statistically significant (p53 mRNA: F=6.688, P=0.006; miR-29b: F=13.640, P=0.000). The relative expression of p53 mRNA was significantly higher and the relative expression of miR-29b was significantly lower in the TGFβ1 activation groups than those in the HTFs group and siRNA transfection group, the differences were statistically significant (all at P<0.05). Conclusions During the process of HTFs transforming to MFs, the expression of p53 is upregulated and the expression of miR-29b is downregulated, Supressing the expression of p53 can upregulate the expression of miR-29b.There may exist interactions between p53 and miR-29b, which regulate the formation of fibrotic scars. Key words: Glaucoma; Scar; p53; MicroRNA-29b

Hyaluronidase injection for improved tissue dissection in Baerveldt tube surgery.

To describe a novel technique for tissue dissection during Baerveldt tube surgery. We present a technique for posterior dissection of conjunctiva and Tenon tissue for the placement of a glaucoma drainage device. Hyaluronidase is used in the early stages of surgery in order to minimize tissue trauma and facilitate easy dissection even through existing adhesions and conjunctival scarring. The technique facilitates convenient dissection through tissues. We did not experience any intraoperative or postoperative complications. The described technique has substantial advantages for Baerveldt tube surgery, specifically in cases of previous ocular surgery and subsequent conjunctival scarring. It is safe and easy to perform, and should be considered in cases of glaucoma drainage device implantation surgeries.

Global histone modifications predict the outcome of glaucoma surgery

PurposeConjunctival and subconjunctival fibrosis at the surgical site influences the outcome of glaucoma surgery. Since glaucoma surgery initiates a cascade of events that leads to up‐ or downregulation of various genes and the subsequent release of cytokines and growth factors, we analyzed global histone modifications at the site of glaucoma surgery and their relationship with the outcome of glaucoma surgery.Methods44 patients who were scheduled to undergo glaucoma surgery were enrolled in this study. A 4 × 4 mm section of Tenon's tissue with overlying conjunctiva was cut from the eye at the margin of the incision. Primary rabbit anti‐histone antibodies were applied in humidified chamber at the following dilutions: H3 K9 K14 K18 K23 K27Ac at 1:200, H4 K5 K8 K12 K16Ac at 1:200, H3 K4diMe at 1:800 (Abcam), and H4 R3diMe at 1:25 (Millipore). The sections were counterstained with Harris's haematoxylin, dehydrated, and mounted.ResultsUsing histochemical staining, we determined the number of cells that were positive for histone acetylation and demethylation of histones H3 and H4. The patients were divided into high‐ and low‐acetylated or ‐methylated groups accordingly. The low‐acetylation group for H3 K9 K14 K18 K23 K27 and H4 K5 K8 K12 K16 had poorer surgical outcomes based on Kaplan‐Meier plots. The preoperative intraocular pressure was significantly related to acetylation of both H3 K9 K14 K18 K23 K27 and H4 K5 K8 K12 K16 in univariate and multivariate regression analyses.ConclusionsOur findings suggest global histone modifications in the conjunctival and subconjunctival tissues predict glaucoma surgery outcomes. A low acetylation status indicated a poor prognosis for glaucoma surgery. Prognostication using histone modifications might have implications for epigenetic therapy to improve glaucoma surgery outcomes.

Tenonplasty for closing defects during sclerocorneal surgery-A brief review of its anatomy and clinical applications.

To provide insight into the clinical anatomy of Tenon's capsule and to describe a technique to manage sclerocorneal defects using autologous Tenon's tissue. A thin layer of Tenon's capsule harvested from the patient's own eye is used to seal the defect and act as a scaffold. The Tenon's flap is spread over the defect and held in place by Vicryl sutures. A bandage contact lens is then placed on the eye. Tenon's capsule is composed of thick fibrous tissue with smooth muscle fibers and a thin posterior capsule of orbital fat. It is rich in fibroblasts, which can accelerate wound healing and eventually lead to robust scarring without risk of immunogenicity and without cost. Tenonplasty uses easily-available autologous Tenon's tissue in patients with sclerocorneal defects to preserve globe morphology. The technique is a feasible alternative not limited by the availability of graft tissue. Clin. Anat. 31:72-76, 2018. © 2017 Wiley Periodicals, Inc.

Anti-scarring effects of butaprost on human subconjunctival Tenon's fibroblasts.

To investigate the toxicity of the E-prostanoid 2 (EP2) receptor agonist, butaprost against human subconjunctival (Tenon's capsule) fibroblasts, and to determine the underlying mechanism. We isolated Tenon's fibroblasts from the subconjunctival area of healthy subjects and evaluated the types of EP receptors expressed using quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). The toxicity of butaprost against the fibroblasts was evaluated using methyl thiazolyl tetrazolium and lactic dehydrogenase assays. The inhibition of conjunctival fibroblast proliferation by butaprost was assessed by measuring α-actin levels. The underlying mechanism was assessed by measuring intracellular cyclic adenosine monophosphate (cAMP) levels. Intergroup differences were statistically analyzed using an independent t-test. Densitometry of the Western blot bands was performed using the Image J software. Quantitative real-time RT-PCR revealed that the fibroblast EP2 receptor levels were higher than those of the other EP receptors. Butaprost did not show toxicity against Tenon's tissue, but inhibited conjunctival fibroblast proliferation by reducing collagen synthesis. EP2 receptor activation enhanced the cAMP cascade, which might be an important mechanism underlying this effect. Butaprost effectively reduces the subconjunctival scarring response. Given the significance of wound healing modulation in blebs, butaprost's inhibitory effect on subconjunctival Tenon's fibroblasts may be beneficial in managing postoperative scarring in glaucoma surgery.

Femtosecond Laser Assisted Pterygium Surgery.

Pterygium is a prevalent ocular surface disorder. Conjunctival autografting (CAG) after pterygium resection is the gold standard treatment. Thinner CAGs without Tenon tissue provide better results but are technically difficult to achieve. We report on the first femtosecond laser (FSL)-assisted pterygium surgery (FLAPS) in humans. In a clinical trial, we treated 6 eyes of 5 patients with FLAPS. After manual removal of the pterygium, CAGs were dissected with the Ziemer Z8 at 60-μm depth and glued into the resection defect. CAG thickness and diameter were measured. The CAG area measured 17.9% smaller than the laser settings (P = 0.03). Central (75.6 ± 13.7 μm) and peripheral (77.7 ± 13.2 μm) CAG thickness did not differ significantly (P = 0.3). No buttonholes or CAG tags occurred. The mean dissection time was 19.5 ± 1.2 seconds, and the time to remove the FSL-prepared CAG and to unfold it onto the cornea was 10.3 ± 3.8 seconds. During 35.8 ± 38.0 days of follow-up, no postoperative complication or recurrences occurred. The conjunctival epithelium had healed at the CAG resection site within 1 week with no evidence of scarring. FLAPS is a new technique, in which the preparation of an ultrathin CAG is done by the FSL. After optimization in porcine eyes, the clinical trial in the first 6 eyes was performed without any complications and the FSL might assist in further standardizing the surgical procedure. Longer follow-up and larger cohorts are needed to assess recurrence rates.