Diagnosis and management of non-infectious immune-mediated scleritis: current status and future prospects.

Scleritis is an inflammatory process of the sclera and adjacent tissues with a wide spectrum of clinical presentations and co-morbidities. Careful clinical history taking, detailed ocular examination, and appropriate investigation for likelihood of an underlying systemic disease are essential for diagnosis. Treatment can be quite challenging in some cases. Conventional therapy with corticosteroids and immunosuppressive agents may not be sufficient to control ocular inflammation in refractory patients. In such cases new therapeutic agents, which have a more targeted and sustained effect on the immune response, so-called biologic response modifiers, are being used. This review focuses on both diagnosis and therapeutic options including traditional and emerging therapies of non-infectious scleritis.

Effect of olmesartan on leukocyte recruitment in choroid-sclera complex in hypercholesterolemia model.

PURPOSE: Demonstrate that the blockade of angiotensin II AT-1 receptors, through the systemic administration of olmesartan, can reduce the MCP-1 expression and the resulting macrophage accumulation in the choroid and sclera of hypercholesterolemic rabbits. METHODS: Thirty-two New Zealand rabbits were divided into 3 groups: group I (GI) was fed a standard rabbit diet; group II (GII) was fed a hypercholesterolemic diet; and group III (GIII) was fed a hypercholesterolemic diet plus olmesartan. Serum levels of total cholesterol, triglyceride, HDL cholesterol, and blood glucose were determined in fasting rabbits at the beginning of the experiment and on the day of euthanasia. The choroid and sclera were submitted to morphometric analysis as well as immunohistochemical analysis with MCP-1 and RAM-11 (macrophage marker) antibodies. RESULTS: No abnormality was detected in GI. Group II and III had significant increases in choroid-sclera complex thicknesses when compared with group I (P<0.001). GII showed a significant increase in immunoreactivity for MCP-1 in relation to GI (P=0.001) and GIII (P=0.004). GII showed a significant increase in immunoreactivity for RAM-11 of the choroid-sclera complex in relation to GI (P<0.001) and GIII (P=0.034). A significant increase in immunoreactivity for RAM-11 was observed in GIII in relation to GI (P=0.008). CONCLUSION: Olmesartan reduced the MCP-1 expression and the resultant macrophage accumulation in the choroid-sclera complex of hypercholesterolemic rabbits.

Infiltrating macrophages in extratumoural tissues after brachytherapy of uveal melanoma.

PURPOSE: To compare distribution of macrophages in extratumoural ocular tissues in enucleated eyes with irradiated and nonirradiated uveal melanomas to find out how irradiation affects distribution of macrophages so as to gain insight into their potential routes of migration and changes in local inflammatory responses. METHODS: Thirty-four matched pairs of primarily enucleated nonirradiated and secondarily enucleated irradiated eyes with choroidal and ciliary body melanoma were stained with mAb PG-M1, and the extratumoural immunopositive elements were counted under the microscope. Main outcome variables were the number of macrophages in the sclera underlying the tumour, in the choroid adjacent to the tumour, and in the ciliary body. The number of macrophage aggregates in the anterior ipsi- and contralateral episclera adjacent to the limbus was also counted. RESULTS: Macrophages were more numerous within the sclera under the tumour in irradiated eyes when compared to primarily enucleated eyes (median 1514 versus 619/mm², p = 0.0001), and more aggregates of episcleral macrophages adjacent to the limbus were found after irradiation (ipsilateral side, median 132 versus 0, p = 0.0034; contralateral side, median 79 versus 0, p = 0.014). In primarily enucleated eyes, increasing numbers of tumour-infiltrating macrophages were associated with presence of higher numbers of macrophages in the ciliary body (p = 0.003) and the adjacent choroid (p = 0.044), whereas in the irradiated eyes, increasing numbers of tumour-infiltrating macrophages (p = 0.010) and increasing extent of necrosis (p < 0.001) were associated with higher numbers of intrascleral macrophages underlying the tumour. CONCLUSIONS: Resident macrophages are present in extratumoural tissues in eyes with uveal melanoma. Brachytherapy may alter their route of migration and increase the number of macrophages in the sclera and episclera. Histopathologically detectable episcleral aggregates of macrophages adjacent to the limbus are detected predominantly after irradiation, a population of which is clinically visible as episcleral deposits after irradiation.

Freeze-drying as an alternative method of human sclera preservation.

PURPOSE: To compare the effect of preserving sclera samples in either 95% ethanol or freeze-dried. METHODS: Ninety-six samples of human sclera were studied. Half of them were freeze-dried and half preserved in 95% ethanol. Preservation periods of 18, 45, 90 or 174 days were studied. Automated immunostaining was carried out in the Ventana BenchMarkR LT platform using collagen 1 and fibronectin antibodies. Histological staining was also performed with hematoxilin-eosin and Masson trichrome. Samples were classified according to the degree of collagen fiber parallelism (0-2), intensity of Masson staining (0-2), and the expression of both antibodies (0-3). Friedman and Wilcoxon tests were applied to compare preservation methods and p-values below 0.05 were considered to ensure statistical significance. RESULTS: Relevant results were found in three situations: (i) Friedman's test showed better collagen fiber integrity in the freeze-dried group rehydrated after 174-days as compared to the 90-day group; (ii) Wilcoxon's test showed better collagen fiber integrity in the freeze-dried group after 18 and 174 days as compared to the ethanol group; (iii) the freeze-dried group disclosed higher immunohistochemical expression for COL-1 antibody in the sclera samples rehydrated after 45, 90 and 174 days as compared to the ones rehydrated after 18 days. CONCLUSION: Histological and immunohistochemical analysis showed freeze-drying to be a superior method for sclera preservation as compared to 95% ethanol. This technique provides an easy method to manipulate tissue, with longer shelf life, and storage at room temperature.

Freeze-drying as an alternative method of human sclera preservation / Liofilização como alternativa à preservação de esclera humana

PURPOSE: To compare the effect of preserving sclera samples in either 95 percent ethanol or freeze-dried. METHODS: Ninety-six samples of human sclera were studied. Half of them were freeze-dried and half preserved in 95 percent ethanol. Preservation periods of 18, 45, 90 or 174 days were studied. Automated immunostaining was carried out in the Ventana BenchMarkR LT platform using collagen 1 and fibronectin antibodies. Histological staining was also performed with hematoxilin-eosin and Masson trichrome. Samples were classified according to the degree of collagen fiber parallelism (0-2), intensity of Masson staining (0-2), and the expression of both antibodies (0-3). Friedman and Wilcoxon tests were applied to compare preservation methods and p-values below 0.05 were considered to ensure statistical significance. RESULTS: Relevant results were found in three situations: (i) Friedman's test showed better collagen fiber integrity in the freeze-dried group rehydrated after 174-days as compared to the 90-day group; (ii) Wilcoxon's test showed better collagen fiber integrity in the freeze-dried group after 18 and 174 days as compared to the ethanol group; (iii) the freeze-dried group disclosed higher immunohistochemical expression for COL-1 antibody in the sclera samples rehydrated after 45, 90 and 174 days as compared to the ones rehydrated after 18 days. CONCLUSION: Histological and immunohistochemical analysis showed freeze-drying to be a superior method for sclera preservation as compared to 95 percent ethanol. This technique provides an easy method to manipulate tissue, with longer shelf life, and storage at room temperature.

OBJETIVO: Comparar dois métodos de preservação de esclera humana, liofilização e álcool 95 por cento, em diferentes períodos de tempo. MÉTODOS: Foram avaliados 96 fragmentos de seis escleras humanas. Metade das amostras foi submetida ao processo de liofilização e metade conservada em álcool 95 por cento. Dois fragmentos de cada grupo foram avaliados pelas colorações de hematoxilina-eosina e tricrômio de Masson e submetidos a técnica de imuno-histoquímica para os anticorpos fibronectina e colágeno 1, após 18, 45, 90 e 174 dias de preservação. Os espécimens foram classificados de acordo com o paralelismo (PF:0-2) e integridade (IF:0-1) das fibras de colágeno e expressão imuno-histoquímica para os anticorpos fibronectina (FIB:0-3) e colágeno 1 (COL-1:0-3). A análise estatística foi realizada por meio dos testes de Friedman e Wilcoxon e o valor de p menor que 0,05 foi considerado estatisticamente significante. RESULTADOS: Verificaram-se diferenças significantes em três situações: (i) maior integridade das fibras de colágeno das escleras liofilizadas após 174 dias quando comparado aos 90 dias; (ii) maior expressão imuno-histoquímica para o anticorpo COL-1 nas amostras de escleras liofilizadas após os 18 dias iniciais de preservação; (iii) maior integridade das fibras de colágeno das escleras liofilizadas após 18 e 174 dias quando comparado às escleras preservadas em álcool. CONCLUSÕES: A preservação de tecido escleral por liofilização mostrou-se técnica tão eficaz quanto a preservação em álcool, apresentado vantagem quando considerada a integridade das fibras de colágeno. A liofilização mostra-se benéfica por permitir a estocagem do tecido em temperatura ambiente e com prazo de validade estendido.

Conjunctival and episcleral Splendore-Hoeppli phenomenon.

The Splendore-Hoeppli phenomenon originally described in 1908 is a rare pathological state with an as yet unknown cause. Reported is the Splendore-Hoeppli phenomenon present in both eyes of a 36-year-old woman. The pathology then proceeded to resolve itself completely within 10 weeks. Of note was the fact that the patient actually developed these granulomata despite being on high doses of oral steroids with the lesions disappearing despite her steroids being withdrawn during the resolution phase. An indication is that the phenomenon is unlikely to be because of an autoimmune response.

Identification of resident and inflammatory bone marrow derived cells in the sclera by bone marrow and haematopoietic stem cell transplantation.

AIMS: To characterise bone marrow derived cells in the sclera under normal and inflammatory conditions, we examined their differentiation after transplantation from two different sources, bone marrow and haematopoietic stem cells (HSC). METHODS: Bone marrow and HSC from green fluorescent protein (GFP) transgenic mice were transplanted into irradiated wild-type mice. At 1 month after transplantation, mice were sacrificed and their sclera examined by histology, immunohistochemistry (CD11b, CD11c, CD45), and transmission and scanning electron microscopy. To investigate bone marrow derived cell recruitment under inflammatory conditions, experimental autoimmune uveitis (EAU) was induced in transplanted mice. RESULTS: GFP positive cells were distributed in the entire sclera and comprised 22.4 (2.8)% (bone marrow) and 28.4 (10.9)% (HSC) of the total cells in the limbal zone and 18.1 (6.7)% (bone marrow) and 26.3 (3.4)% (HSC) in the peripapillary zone. Immunohistochemistry showed that GFP (+) CD11c (+), GFP (+) CD11b (+) cells migrated in the sclera after bone marrow and HSC transplantation. Transmission and scanning electron microscopy revealed antigen presenting cells among the scleral fibroblasts. In EAU mice, vast infiltration of GFP (+) cells developed into the sclera. CONCLUSION: We have provided direct and novel evidence for the migration of bone marrow and HSC cells into the sclera differentiating into macrophages and dendritic cells. Vast infiltration of bone marrow and HSC cells was found to be part of the inflammatory process in EAU.

Ocular lesions in Watanabe heritable hyperlipidemic rabbits.

Hyperlipidemic ocular lesions are described for Watanabe heritable hyperlipidemic (WHHL) rabbits. Male WHHL rabbits 8 months old exhibited serum hyperlipidemia and ophthalmoscopically yellowish-white lesions along the corneoscleral junction and in the iris. Histopathologically, foamy macrophages aggregated in the stroma of the cornea, iris, and ciliary body were observed. These findings have been interpreted as lipid keratopathy. In addition, multiple clusters of a large number of foamy macrophages occurred throughout the choroid and sclera in association with the blood vessels. The lesions in the choroid and sclera could not be detected ophthalmoscopy, yet were much more prominent than those in the cornea, iris, and ciliary body, suggesting greater involvement and earlier onset of lipidosis at these sites associated with hyperlipidemia in WHHL rabbits.

Characterisation of the normal conjunctival leukocyte population.

Lymphoid cells are present in normal mucosal tissue as scattered cells or organised into MALT. Knowledge of the non-pathological conjunctival lymphoid tissue is a vital basis for the further study of ocular surface inflammatory disorders. Therefore, we used immunohistochemistry to examine the leukocyte population of tarsal and bulbar conjunctiva from normal patients with no ocular or systemic inflammatory disease. CD3+ T cells were the most frequently occurring, and macrophages the second most frequently occurring, conjunctival cell type and were seen in the epithelium and substantia propria. There were greater numbers of leukocytes in the bulbar than in the tarsal area and this reached statistical significance for CD3+ T cells and CD57+ NK cells. In both bulbar and tarsal conjunctiva, B cells and neutrophils were seen in the epithelium and substantia propria, but plasma cells, NK cells and mast cells were present only in the substantia propria. No eosinophils were seen. CD8+ cells outnumbered CD4+ cells in the epithelium (CD4:CD8 0.3) but this was reversed in the substantia propria (CD4:CD8.1.3 tarsal, 2.0 bulbar). Most epithelial T cells and half the stromal T cells were CD45Ro+. IL-2R (CD25) staining was infrequent in the tarsal but not the bulbar area. The greater number and activation of T cells in the bulbar region may relate to greater antigen exposure. HLA-DR+ cells were mainly macrophages, but also included dendritic cells in the epithelium and a few epithelial cells. The conjunctival lymphocytes do have certain features of MALT cells, apart from mucosal recirculation, homing and promotion of sIgA production. Conjunctival IEL, like gut IEL, are predominantly CD8+, are found in the basal epithelium, are HML-1+, and have very high expression of CD45Ro. Substantia propria lymphocytes have more equal CD4 and CD8 numbers and frequently express CD45Ro. We found only one example of organised conjunctival lymphoid tissue in our study and suggest that the presence of CALT in humans is not universal.

Antibacterial protection of the ocular surface.

The outer surface of the eye is constantly exposed to a wide array of microorganisms. To protect the integrity or the ocular surface and to retain corneal transparency, a number of defense mechanisms have evolved. This article discusses the host mechanisms of the eyelids-, tears, cornea and conjunctiva. These host defense mechanisms are identified as either a native, nonspecific defense or a specifically acquired immunological defense requiring previous exposure to an antigen and the development of specific immunity. Nonspecific components that protect the eye include the eyelids, ocular surface epithelium, normal flora and tear proteins. Specifically acquired immunity in tears, cornea and conjunctiva involves the interaction of antigen-presenting cells, lymphocytes and humoral components of the immune system.

[Clinical and immunological criteria of the activity of inflammatory reaction and autolymphokine therapy in penetrating wounds of the eye]. / Kliniko-immunologicheskie kriterii aktivnosti vospalitelnoi reaktsii i autolimfokinoterapiia pri pronikaiushchikh raneniiakh glaza.

Clinical and immunological criteria of an unfavorable course of posttraumatic process were defined and the efficacy of autolymphokine therapy in the postoperative treatment of patients with penetrating wounds to the eye assessed. A total of 119 patients were examined. Autolymphokine therapy supplemented the traditional postoperative treatment in 38 of them. An unfavorable course of the posttraumatic period was associated with high levels of tumor necrosis factor-alpha and interleukin-1-beta in the blood serum and lacrimal fluid, with accumulation and long persistence of high titers of antibodies to lens antigens and retinal S-antigen in the lacrimal fluid, with intensive cellular immune response to these antigens in the leukocyte migration inhibition test, and with a deficit of tissue-specific anticorneal antibodies in the lacrimal fluid during the first 3-4 weeks after the injury. In the event of a favorable outcome the cytokines were detected in the minimal amounts, and antibody titers were moderate. Autolymphokine therapy 2 to 3 times decreased the concentration of cytokines in the lacrimal fluid, maintained the moderate level of autoantibodies in the lacrimal fluid, decreased the incidence of the leukocyte migration inhibition and the duration of its detection, and shortened the period of autoantibody detection in the blood serum.

Macrophages during fibrosis following scleral fistulising surgery in a rat model.

PURPOSE: Glaucoma filtration surgery can fail in a minority of patients as a result of fibrosis in the subconjunctival bleb space and closure of the scleral fistula. In this study, the rat eye has been used as an experimental model for fistulising surgery in order to evaluate the clinical manifestation of bleb failure with the morphological events of the wound healing process. METHODS: A conjunctival bleb was successfully formed in 25 rats and was examined daily using slit lamp microscopy to evaluate postoperative inflammation and the presence of a bleb. At defined post-operative time points, serial frozen sections of eyes were stained immunohistochemically using a panel of monoclonal antibodies directed against known surface markers on rat immune/inflammatory cells. Positively stained cells were counted (a) in the bleb site, (b) at the sclerostomy and (c) at the suture site. RESULTS: Following an initial post-operative inflammation, a surgically formed sclerostomy and conjunctival bleb underwent a granulation and scarring response so that by 7-19 days the bleb had disappeared. Using the monoclonal antibodies applied in this study, it was possible to show that macrophages most likely play a major and pivotal role throughout the sequence of events that lead to repair of the fistula and closure of the bleb. It was also noted that the presence of an otherwise inert nylon suture used to close the incised conjunctiva can serve as a focus for macrophages. CONCLUSION: The rat has been successfully used as an experimental model of fistulising surgery and its subsequent failure. The use of a panel of monoclonal antibodies directed against specific surface markers on immune-inflammatory cells, highlighted macrophages to be prominent in all stages of this wound healing process.

Immunopathological findings in posterior scleritis.

Posterior scleritis can present with a variety of symptoms, and its clinical diagnosis is therefore difficult. Little is known about the pathogenesis and the cellular effector mechanisms. This case report presents the immunopathological findings of posterior scleritis in the enucleated eye of a 28-year-old female with no known underlying disease. The cells infiltrating the scleral fibers consisted predominantly of T cells. Many of them were CD4 cells. Clusters of T and B cells were found in perivascular areas. No signs of primary vasculitis were seen. The cellular infiltrate in posterior scleritis shows features compatible with a T-cell-mediated (autoimmune) disorder.

Aspects of the development of Schlemm's canal.

We have tried to answer the question of whether the endothelium of Schlemm's canal is derived from and retains properties of blood vessels by studying: (1) the development of Schlemm's canal in human fetal eyes; (2) the existence of Weibel-Palade bodies in human neonatal, adult human and adult monkey eyes; and (3) the presence of blood coagulation Factor VIII-related antigen in adult human and monkey eyes. (1) We observed that the intrascleral plexus of the limbal region extended deep into the sclera forming a deep scleral plexus by the 17th week of gestation. After 17 weeks gestation, extensions from the deep scleral plexus had reached the region of the future corneoscleral meshwork where the trabecular cells appeared oriented circumferentially. The blind endings of these extensions appeared to grow circumferentially in the supposed region of Schlemm's canal and at 27 weeks gestation they formed an incomplete Schlemm's canal. A complete Schlemm's canal was observed in some sections of the limbal region at 28 weeks gestation and at approximately 40 weeks gestation the canal was complete in most sections. (2) Weibel-Palade bodies were found in the endothelium of aqueous veins and in the inner and outer wall endothelium of Schlemm's canal. (3) Blood coagulation Factor VIII-related antigen was detected in the endothelium of the collector channels and Schlemm's canal, as well as in the blood vessels of the other parts of the eye. Our results indicate that the endothelium of Schlemm's canal is derived from a vascular origin and that even in the adult eye it retains some of the properties of a blood vessel.

Necrotizing scleritis after ocular surgery. A clinicopathologic study.

Necrotizing scleritis may appear after trauma to the sclera. The authors studied 10 patients in whom necrotizing scleritis developed after ocular surgery. The interval between surgery and onset of scleritis varied from 2 weeks to 6 months. Nine patients (90%) were found to have an underlying autoimmune vasculitic systemic disease, which was subsequently treated with immunosuppression. One patient was found to have a local infectious process, which was treated with antibiotics. Appropriate studies led to the discovery and subsequent treatment of a systemic disease or an infectious process in 6 of the 10 patients; the other 4 patients had been previously diagnosed. Results of immunohistochemical studies on resected conjunctival and/or sclera suggest local immune complex deposition, increased HLA-DR expression, and increased helper T-cell participation in conjunctiva and/or scleral tissues after trauma in patients with underlying systemic autoimmune vasculitic disease. The results emphasize the need for meticulous diagnostic pursuit of potentially lethal systemic autoimmune vasculitic disease in patients with necrotizing scleritis after intraocular surgery.

[A theory on the role of immunologic factors in the pathogenesis of primary glaucoma]. / Kontseptsiia uchastiia immunnykh faktorov v patogeneze pervichnoi glaukomy.

Basing on the literature data and their own clinical, immunomorphologic, and immunochemical findings in glaucoma patients and normal subjects, the authors suggest a concept on the immune factor contribution to the pathogenesis of primary open-angle glaucoma. According to the scheme they suggest, of primary importance in the development of autoimmune reactions in glaucoma are the following factors: changed antigenic specificity of the drainage zone tissues, resultant from involution processes; impaired immune homeostasis, effects of various internal and environmental factors. The pathogenetic role of autoimmune reactions and immunity system regulatory mechanism disorders is explained.

Immunopathology of scleritis.

Conjunctival and scleral biopsies from 25 patients with necrotizing scleritis and 5 patients with recurrent nonnecrotizing scleritis were studied by histopathologic, immunofluorescence, and immunoperoxidase techniques. Vasculitis with fibrinoid necrosis and neutrophil invasion of the vessel wall was present in 75% of the scleral and 52% of the conjunctival specimens. Vascular immunodeposits were found in 93% of the scleral and 79% of the conjunctival tissue tested by immunofluorescence techniques. A dramatic increase in the number of inflammatory cells over normal controls was detected in both tissues by immunoperoxidase techniques. In the conjunctival epithelium, there were significantly more T-helpers, macrophages, and B cells. In the conjunctival substantia propria, there were significantly more T cells of all types, macrophages, and B cells. Likewise, scleral specimens showed an increase over controls of T cells of all types and macrophages. HLA-DR expression was dramatically increased in both tissues. Immune-complex-mediated vasculitis plays a pivotal role in the pathogenesis of necrotizing scleritis and recurrent nonnecrotizing scleritis. Induced HLA-DR expression on ocular nonimmune cells and T cell controlled responses also may participate.

Scleral fibroblasts. Human leukocyte antigen expression and complement production.

The authors investigated the ability of recombinant human gamma-interferon (rhIFN-gamma) to influence production of complement and expression of human leukocyte antigens (HLA) by human scleral fibroblasts in culture. Cell cultures were established by explanting sclera from normal human donor eyes. To study complement production, fibroblasts were treated with 500 units/ml rhIFN-gamma in cell culture, and media were tested for complement components by hemolytic assay after 0, 1, 3, 6, 9, and 11 days. To induce Class II HLAs, fibroblasts were exposed to rhIFN-gamma at concentrations ranging from 10-500 units/ml and incubated for 1, 3, and 6 days. The HLAs were detected by immunofluorescence in conjunction with flow cytometry. Class I antigen was detected using a monoclonal antibody directed against beta 2-microglobulin. Class II histocompatibility antigens were identified using monoclonal antibodies specific for HLA-DR, -DP, and -DQ. Although complement component C1 was produced constitutively in cell culture, the addition of rhIFN-gamma resulted in an increase in production. Complement components C2 and C4 were detected only after treatment with rhIFN-gamma. Complement production was completely inhibited by cycloheximide, and C3, C5, C6, and C7 were not present in cell culture media with or without rhIFN-gamma. Class I antigen was present on all cells before induction, and an increase in expression was noted after exposure to rhIFN-gamma. Class II antigens were absent before induction with rhIFN-gamma. After treatment with rhIFN-gamma, scleral fibroblasts expressed HLA-DR, -DP, and -DQ in a dose-dependent, time-related fashion. These findings suggest that rhIFN-gamma has multiple effects on scleral fibroblasts: (1) increased production of C1, (2) production of C2 and C4, (3) up-regulation of Class I antigen expression, and (4) expression of Class II antigens. They also suggest that scleral fibroblasts have the potential to participate in immunologic diseases of the eye.

Nonabsorbable suture material in corneoscleral sections--a comparison of novafil and nylon.

We compared a newly available nonabsorbable monofilament ophthalmic suture, 9/0 Novafil (Davis & Geck), with 10/0 nylon (Alcon), currently the most popular suture for closure of corneoscleral sections. Surgery was performed on nine rats and ten rabbits. In each case a 120 degrees corneoscleral section was made in each eye and closed with interrupted sutures of 9/0 Novafil in one eye and 10/0 nylon in the other. We compared their handling qualities during surgery, as well as their effect on postoperative wound inflammation. In addition we examined the suture material from each eye of the rats by scanning electron microscopy (SEM) after 3 months, and we compared the surgically induced astigmatism in the rabbits in the two suture groups. Both suture materials were easy to handle and well tolerated. Nylon sutures from six of the eight rat eyes studied showed SEM evidence of surface disintegration after 3 months, whereas all the Novafil sutures remained intact.