Severe Ocular Surface Disorders Research Articles

Medium term results in keratoprostheses with biocompatible and biological haptic

Corneal grafts or limbal stem cell transplantation are often unsuccessful in patients with severe ocular surface disorders such as severe dry eye syndrome, symblepharon or diffuse vascularisation. In those patients, a keratoprosthesis (KPro) may be an alternative for the recovery of vision. Various KPro differ from each other in the material of the haptic that supports the optic cylinder. The haptic may be made of biocompatible or biological material such as tibia bone (TKPro) or dentine and alveolar bone (osteo-odonto-keratoprosthesis, OOKP). On the basis of our experience, we wanted to comment on the value of different KPro. Over the last 10 years we have implanted a total of 35 KPro, 29 with biological haptic (25 OOKP and four TKPro), and six KPro with biocompatible haptic (one Legais KPro, five Pintucci KPro). A follow up examination was carried out approximately every6 months. The patients gained a visual acuity of > or =0.9 in 20.6%, of > or =0.5 in 52.9%, of > or =0.2 in 61.8% and a significant improvement in visual acuity in 76.5%, respectively. There was no significant difference between the various types of KPro concerning the best postoperative visual acuity. All patients showing poor improvement had a pre-existing end stage secondary glaucoma or other retinal damage. The median follow-up was 2.9 years (maximum 8) for OOKP, 1 year for TKPro, 1 year (maximum 2) for Pintucci Kpro and 6 month for Legeais KPro. During this period, only one of the KPro with biological haptic was lost (one TKPro after 1 year), compared with four out of six of the KPro with biocompatible haptic (P<0.0001). Fixation of the KPro by a root of the patient s own tooth (OOKP) leads to the best results in the long-term follow up, as our results as well as the literature demonstrate. As long as a KPro is in place, the visual acuity is as good as the retinal function. For the ranking of different types of KPro, the percentage and the duration of the anatomic success are most important. The comparability of the various KPro results may be limited, since the patients were not randomised and the four groups differ in number.

An optimised protocol for the production of autologous serum eyedrops

Serum eyedrops have been successfully used in the treatment of severe dry eye, persistent epithelial defects and other severe ocular surface disorders. A number of clinical studies showed a variable efficacy of this approach, but the parameters for the production of this blood product varied significantly. In order to establish an optimised protocol for the production of serum eyedrops, we examined the effect of various clotting times, centrifugation forces, types of diluent and dilutions on the concentration of growth factors, fibronectin, and vitamins in serum and tested the epitheliotrophic capacity of these serum modifications in a cell culture model of human SV-40-immortalised corneal epithelial cells (HCE-T). Serum samples were prepared with a clotting time of 20, 60 or 120 min, a centrifugation force of 500 xg or 3,000 xg, and diluted with BSS or isotonic saline. The concentrations of EGF, TGF-beta1, PDGF-AB, FGF, HGF, fibronectin, vitamin A and vitamin E in these samples were evaluated with ELISA and HPLC. HCE-T cells were incubated for 24, 48, 72, 96 and 144 h with 100, 50, 25, 12.5, 6.25 and 3.125% serum in diluent, and cell proliferation, migration and differentiation were evaluated by means of a luminescence-based ATP assay, a colony-dispersion assay and scanning electron microscopy. Using a longer clotting time resulted in an increased concentration of all the epitheliotrophic factors examined in serum; the difference was statistically significant for EGF, TGF-beta1 and HGF. Increasing the g force of centrifugation from 500 xg to 3,000 xg resulted in significantly less TGF-beta1, but more EGF and vitamin A. Cell proliferation was better supported by serum prepared with 3,000 xg and diluted with BSS. Serum prepared with a longer clotting time yielded better cell migration and differentiation. Clotting time, centrifugation and diluents have a significant impact on the composition and epitheliotrophic effects of serum. A long clotting time (>or=120 min), a sharp centrifugation (3,000 xg for 15 min) and dilution with BSS improve the ability of serum eyedrops to support proliferation, migration and differentiation of corneal epithelial cells.

Traitement des syndromes secs graves par sérum autologue

Dry eye syndrome with tear deficiency can be improved with artificial tears, which can be associated with topical anti-inflammatory agents. Autologous serum can provide the ocular surface with beneficial growth factors and vitamins. Twenty-one patients suffering from severe dry eye due to Sjögren's syndrome were treated with 20% autologous serum for 2 Months. The Schirmer I test, break-up time, and fluorescein and lissamine green stainings were performed before and after treatment. Subjective complaints such as burning, foreign body sensation, dryness and photophobia were assessed by a questionnaire as well as a face score reflecting the current condition of patients' eyes. Lissamine green and fluorescein scores improved significantly as well as subjective symptoms of burning, foreign body sensation and dryness (p<0.05). The face score was significantly improved. Bacterial culture of serum delivered to the patients all remained negative. Autologous serum provides growth factors and vitamins that are useful for an altered ocular surface due to Sjögren's disease. However, some problems still remain: risk of contamination, arbitrary dilution of autologous serum, and a current lack of regulations for use of autologous serum. A close collaboration between ophthalmologists and the Etablissement Français du Sang (French Blood Bank) is mandatory because autologous serum should be considered as a useful tool to treat severe ocular surface disorders. The use of autologous serum improved symptoms and objective signs caused by severe Sjögren's syndrome. Currently, a lack of clear regulations prevents its widespread use in severe ocular surface disorders.

Transplantable cultivated mucosal epithelial sheet for ocular surface reconstruction

Ocular surface reconstruction by tissue engineering using somatic stem cells is a second-generation therapeutic modality. In view of future treatment of bilaterally affected, severe ocular surface disorders, two types of transplantable cultivated mucosal epithelial sheets can be used for reconstruction. One is an allogeneic corneal epithelial stem cell sheet, and the other is an autologous oral mucosal epithelial cell sheet. We first investigated the feasibility of amniotic membrane as an epithelial carrier, and found that denuded amniotic membrane was the most appropriate substrate for this purpose. Thus, cultivated corneal epithelial stem cell sheets were created by co-culturing with 3T3 fibroblast and air-lifting on amniotic membrane. These epithelial sheets demonstrated positive keratin 3 and 12 specific to in vivo corneal epithelium, tight junction related proteins and proliferative activity. The transplanted allogeneic human corneal epithelial sheets existed successfully on the corneal surface, and were quite effective in achieving ocular surface stability in severe ocular surface disorders. A few cases, however, developed immunological reactions or opportunistic infections, etc. Secondly, we established transplantable autologous cultivated oral mucosal epithelial sheets in rabbits. The in vitro oral mucosal epithelial sheets showed histological characteristics similar to those of in vivo corneal epithelial sheets; for example, positive keratin 3 expression. Based on the fact that, the transplanted autologous oral mucosal epithelial sheets resembled corneal epithelium and that we achieved the recovery of corneal transparency in rabbits, we propose that cultivated oral mucosal epithelium may become the substitute for corneal epithelium in ocular surface reconstruction.

Ocular surface reconstruction update.

Ocular surface reconstruction (OSR) is now a standard procedure in the treatment of severe ocular surface disorders. The past few years have revealed the long-term results of patients who were operated on during the early stages of OSR development, and we now have a more realistic view of the benefits and limits of the procedure. On the other hand, further understanding of the physiologic role played by the amniotic membrane (AM) has opened doors to further refined techniques in treating these patients. This review will introduce some of the major contributions made during the past years in the advancement of OSR. Clinically, we are at a stage of reviewing the pros and cons of the various transplantation techniques. Identification of factors crucial for a successful OSR procedure will further improve surgical results. Basic researchers are on the verge of identifying the so-called limbal stem cells, and further understanding of AM physiology will lead the way to tissue engineering techniques as another alternative in OSR surgery.

Long-term outcomes of keratolimbal allograft for the treatment of severe ocular surface disorders

Purpose To investigate the long-term outcome of keratolimbal allograft (KLAL) for the treatment of severe ocular surface disorders. Design Retrospective, noncomparative case series. Participants Twenty patients (23 eyes) with severe ocular surface disorders. Intervention Thirty-three KLAL procedures were performed. Ten patients (10 eyes) underwent KLAL in combination with other surgical procedures. Oral or topical cyclosporine or both were used after surgery in 15 patients to prevent allograft rejection. Main outcome measures Reconstruction of the ocular surface with restoration of phenotypic corneal epithelium, reduction of corneal vascularization and conjunctivalization, decreased pain, and visual improvement. Results The mean follow-up was 60 months (range, 15–96 months). Eight eyes (24.2%) never reepithelialized and were considered primary failures. The remaining 25 grafts initially restored a phenotypic corneal epithelium, but at last follow-up only 7 (21.2%) were stable. Graft survival rate was 54.4% at 1 year, 33.3% at 2 years, and 27.3% at 3 years. Visual acuity improved or was unchanged in 19 eyes (82.6%) and decreased in 4 eyes (17.4%). Seventeen corneal transplantations (3 lamellar keratoplasties and 14 penetrating keratoplasties) were performed either in combination with or after a KLAL. All three lamellar keratoplasties were successful, whereas 13 of the 14 penetrating keratoplasties failed. Cyclosporine was used initially in high-risk recipients and later in all recipients. Allograft rejection episodes occurred in 13 KLAL procedures of 11 eyes (39.4%) and were more common in patients treated with cyclosporine compared with the untreated group (87.5% vs. 22.2%). Graft survival was longer in the cyclosporine-treated group compared with the untreated group. Conclusions Keratolimbal allograft is useful in ocular surface reconstruction and restores phenotypic corneal epithelium. Graft survival rate, however, decreases dramatically over a 2-year period. Long-term use of cyclosporine appears to prolong graft survival but does not prevent acute allograft rejections.

Transplantation of human limbal epithelium cultivated on amniotic membrane for the treatment of severe ocular surface disorders

Purpose To study the short-term clinical results of transplanting of cultivated corneal/limbal epithelial cells on human amniotic membrane (AM) for limbal deficiency. Design Noncomparative, retrospective interventional case series. Participants Thirteen eyes of 13 patients with severe limbal deficiency (Stevens-Johnson syndrome in eight eyes, ocular cicatricial pemphigoid in three eyes, and chemical burns in two eyes) were treated at the department of Ophthalmology, Tokyo Dental College, Japan. Intervention Cultivated allo-limbal epithelium was transplanted onto the ocular surface of patients with severe limbal deficiency. Main outcome measures Ocular surface reconstruction with corneal epithelialization, changes in visual acuity, and postoperative complications were studied. Histologic examinations were also performed on cultivated epithelium. Results Cultivated corneal epithelium on AM formed two to three layers with the formation of basement membrane-like structures. After the surgery, the epithelium regenerated and covered the ocular surface in eight eyes (61.5%). However, three of the eight eyes developed partial conjunctival invasion, and two eyes later developed epithelial defects. At last examination, corneal epithelialization was achieved in six eyes (46.2%). Five eyes had conjunctivalization, one eye had dermal epithelialization, and one eye was not epithelialized. Complications were corneal perforation in four eyes and infectious keratitis in two eyes. Conclusions This study demonstrates that the success rate for transplanting cultivated allo-limbal epithelium on the AM is not different from the conventional limbal and AM transplantation for the treatment of severe limbal stem cell dysfunction.

Long-term outcome of keratolimbal allograft with or without penetrating keratoplasty for total limbal stem cell deficiency

Purpose To evaluate the long-term outcome of ocular surface reconstruction, including keratolimbal allograft (KLAL) and amniotic membrane transplantation (AMT) with or without penetrating keratoplasty (PKP), in patients with nonambulatory vision secondary to total limbal stem cell deficiency (LSCD). Design Retrospective, noncomparative interventional case series. Participants Thirty-nine eyes in 31 consecutive patients with total LSCD, as defined by impression cytology, who had a preoperative best-corrected visual acuity of less than 20/200 and a minimum follow-up of 12 months. Patients were divided into three groups: group 1 (16 eyes) with chemical burns, group 2 (9 eyes) with Stevens-Johnson syndrome (SJS), and group 3 (14 eyes) with other causes of LSCD, including ocular cicatricial pemphigoid, atopic keratoconjunctivitis, and aniridia. Intervention All patients underwent KLAL and AMT by one surgeon (SCGT). If needed, PKP was performed at the same surgical setting using tissue from the same donor. Main outcome measures Cumulative rates of survival of ambulatory vision (≥ 20/200), survival of KLAL, survival of PKP, and incidence of complications. Results Fifty-three KLAL with AMT procedures were performed in 39 eyes, of which 23 eyes received simultaneous PKP at the time of the first KLAL. The mean follow-up was 34.0 ± 21.5 months (range, 12–117.6). The mean period of ambulatory vision was 23.9 ± 20.9 months (range, 0–104). The overall survival of ambulatory vision was 53.6% at 3 years and 44.6% at 5 years. The survival of ambulatory vision was significantly worse in SJS compared with other causes (67%, 81%, and 92% for groups 1, 2, and 3, respectively; P = 0.06 for group 1 versus 2, P = 0.0008 for group 1 versus 3). KLAL performed alone resulted in higher survival of ambulatory vision at 2 years (86.1% ± 9.1%) compared with KLAL with PKP (46.9% ± 10.6%, P = 0.100). The survival of PKP was significantly worse in SJS compared with the other causes (20.0% ± 17.9% compared with 55.6% ± 11.7%, respectively, P = 0.028). After 2 years, the survival of the second KLAL was better than that of the first: 68.2% ± 15.4% compared with 27.3% ± 13.4%, respectively ( P = 0.041). Conclusions Ambulatory vision for a period of more than 2 years can be achieved by KLAL with or without PKP in eyes with severe ocular surface disorders caused by total LSCD. However, a progressive decline of the visual outcome and graft survival is evident with time. Performing PKP simultaneously with KLAL may be associated with a less favorable outcome. The failure of KLAL is associated with the loss of donor cells in the recipient. Augmentation of ocular surface defense is essential in securing the success of KLAL and PKP. Future modifications of the surgical procedure and of the immune suppressive protocols may improve survival of the allogeneic grafts and the final visual outcome.

Reconstruction of ocular surface with heterologous limbal epithelium and amniotic membrane in a rabbit model.

To report in vivo reconstruction of the ocular surface using amniotic membrane and heterologous transplants of epithelial limbal cells in rabbits with chemical burns. After severe damage to the ocular surface with n-heptanol and keratectomy, 15 rabbits developed total limbal deficiency with conjunctival epithelialization, vascularization, and chronic inflammation. One month later, a complete keratectomy was performed in all eyes: 12 received additional transplantation of human amniotic membrane and heterologous limbal epithelial cells in a double amniotic membrane layer, 2 received amniotic membrane only, and 1 control eye received no procedure. After 1 month of follow-up, corneas in eight of the operated eyes presented minimal vascularization, without signs of rejection. Corneal surface reconstruction was demonstrated with the growth of new corneal-like epithelial phenotype and integration of amniotic membrane to the basal corneal surface. A superficial amniotic membrane (with the amnion side up as a dressing) peeled off after 7 to 10 days. The epithelialization with heterologous limbal epithelial cells was evident underneath. The other four operated eyes were followed for 6 months; the ocular surface was also stable with a corneal-like epithelial phenotype. Simultaneous transplantation of amniotic membrane and heterologous limbal epithelial cells in severe ocular surface disorders could restore ocular surface and may be useful in patients with severe bilateral limbal epithelial loss, giving new perspectives for the treatment of severe ocular surface disorders.

Treatment of severe ocular-surface disorders with corneal epithelial stem cell transplantation.

THE NEW ENGLAND JOURNAL OF MEDICINE Treatment of Severe Ocular-Surface Disorders With Corneal Epithelial Stem-Cell Transplantation Kazuo Tsubota, MD; Yoshiyuki Satake, MD; Minako Kaido, MD; Naoshi Shinozaki, MS; Shigeto Shimmura, MD; Hiroko Bissen-Miyajima, MD; Jun Shimazaki, MD Background Conditions that destroy the limbal area of the peripheral cornea, such as the Stevens-Johnson syndrome, ocular pemphigoid, and chemical and thermal injuries, can deplete stem cells of the corneal epithelium. The result is scarring and opacification of the normally clear cornea. Standard corneal transplantation cannot treat this form of functional blindness. Methods We performed and evaluated 70 transplantations of corneal epithelial stem cells from cadaveric eyes into 43 eyes of 39 patients with severe ocular-surface disorders and limbal dysfunction. Medical treatment had failed in all patients. The patients had a mean preoperative visual acuity of 0.004 (only being able to count the number of fingers presented by the examiner) in the affected eyes, which satisfies the criteria for legal blindness in most countries. In 28 eyes, we also performed standard corneal transplantation. Stem-cell transplantations were performed as many as four times on 1 eye if the initial results were not satisfactory; 19 eyes had multiple transplantations. Patients were followed for at least one year after transplantation. Results A mean of 1163 days after stem-cell transplantation, 22 of the 43 eyes (51 percent) had corneal epithelialization; of the 22 eyes, 7 eyes had corneal stromal edema and 15 eyes had clear corneas. Mean visual acuity improved from 0.004 to 0.02 (vision sufficient to distinguish the largest symbol on the visual-acuity chart from a distance of 1 m) (P Conclusions Transplantation of corneal epithelial stem cells can restore useful vision in some patients with severe ocular-surface disorders. N Engl J Med. 1999;340:1697-1703

Systemic ciclosporin A in high-risk keratoplasties.

It was the purpose of this study to compile the results of all high-risk keratoplasties (kp) performed in our hospital under systemic ciclosporin A (Ci A) cover from 1987 through 1994. One hundred and thirty-one keratoplasties were performed. Ci A was administered for an average period of 9.4 months. We aimed at trough levels of 100-150 ng/ml (monoclonal RIA/TDx). The 29 kp in group A were second or third repeat kp and/or the recipient cornea had severe deep vascularization in all quadrants and/or a transplant position at the limbus was inevitable (expected risk: only immune reactions). The 40 kp in group B were threatened by severe ocular surface disorders (without severe limbal stem cell insufficiency) and by immune reactions (atopic keratopathy, keratoconus with severe endogenous eczema or chronic blepharokeratoconjunctivitis). In the 45 kp of group C resurfacing problems from severe limbal stem cell insufficiency and immune reactions were anticipated (severe burns, pseudopemphigoid or Lyell syndrome). Group D comprised 17 kp with various diagnoses (e.g. kp in newborns, rheumatic and Acanthamoeba keratitis). In group A 91% of the grafts were clear 2 years postoperatively, in group B 76%, in group C 38% and in group D 18%. In 32 of 41 failed grafts (78%), resurfacing problems were the only reason for or participated in final graft failure. Immune reactions and other causes of graft failure were of minor importance. (1) Systemic Ci A cover can efficiently suppress immune reactions. (2) With the suppression of immune reactions, resurfacing disorders become the most important single cause for functional graft failure. (3) For eyes with a considerable loss of limbal stem cells, limbal stem cell transplantation should be combined with systemic Ci A cover in order to improve the long-term prognosis for penetrating keratoplasty.

Reconstruction of the Corneal Epithelium by Limbal Allograft Transplantation for Severe Ocular Surface Disorders

Although penetrating keratoplasty is an established surgical procedure, it often is ineffective for severe ocular surface diseases such as alkali burns or limbal deficiency. The authors have performed limbal allograft transplantation for the reconstruction of the corneal epithelium. A total of nine patients (3 with chemical injury, 3 with limbal deficiency with unknown etiology, 2 with moderate ocular pemphigoid [OCP], and 1 with traumatic limbal deficiency) were treated by limbal allograft transplantation. Penetrating keratoplasties were performed in all patients with the exception of one with OCP. Patients received cyclosporine both systemically (10 mg/kg) and topically (0.05%) as well as high-dose intravenous dexamethasone (8 mg). The corneal epithelium was reconstructed in all patients, although two showed partial increased fluorescein permeability and two others required a second surgery. The other five epithelia remained clear at mean follow-up of 12.3 months, with two episodes of graft rejection which were controlled successfully by medication. Limbal allograft transplantation with intensive immunosuppression by cyclosporine and high-dose steroids appears to be a promising surgical intervention for the reconstruction of corneas affected by severe ocular surface disease.

Reconstruction of Corneal Epithelium by Limbal Allograft Transplantation for Severe Ocular Surface Disorders

International Ophthalmology Clinics is a valuable resource for any medical professional seeking to stay informed and up-to-date regarding developments in this dynamic specialty. Each issue of this quarterly publication presents a comprehensive review of a single topic in a new or changing area of ophthalmology. The timely, tightly focused review articles found in this publication give ophthalmologists the opportunity to benefit from the knowledge of leading experts in this rapidly changing field.

Reconstruction of Corneal Epithelium by Limbal Allograft Transplantation for Severe Ocular Surface Disorders

International Ophthalmology Clinics is a valuable resource for any medical professional seeking to stay informed and up-to-date regarding developments in this dynamic specialty. Each issue of this quarterly publication presents a comprehensive review of a single topic in a new or changing area of ophthalmology. The timely, tightly focused review articles found in this publication give ophthalmologists the opportunity to benefit from the knowledge of leading experts in this rapidly changing field.