Limbal Autograft Research Articles

Transplantation of limbal autograft and bulbal conjunctive for patients with pterygium

目的 探讨治疗巨大翼状胬肉及复发性翼状胬肉的有效方法.方法 对27例(27眼)巨大翼状胬肉及复发性翼状胬肉行胬肉切除加自体球结膜移植或自体角膜缘移植联合球结膜移植术.Ⅰ组8例(自体球结膜移植组)翼状胬肉单纯切除后取同眼颞上方球结膜移植于巩膜暴露区,Ⅱ组19例(自体角膜缘移植联合球结膜移植组)翼状胬肉单纯切除后取同眼颞上方结膜角膜缘上皮组织移植于巩膜暴露区.所有病例均在手术显微镜下操作.结果 术后平均随访9.4月,自体球结膜移植组复发Ⅰ例,自体角膜缘移植联合球结膜移植组未见复发.结论 自体角膜缘移植联合球结膜移植治疗翼状胬肉疗效良好。

Sclerocorneal limbal stem cell autograft transplantation in dogs

The effects of sclerocorneal limbal stem cell autograft transplantation in dogs with corneal wounds were studied. Eighteen dogs were divided in two groups (GI and GII). The animals of GI (n=12) underwent limbal transplantation 30 days after the destruction of limbal stem cells. The dogs of GII (n=6) only underwent destruction of stem cells (control group). Light microscopy examination of the right eye was performed on days 3, 7, 14, 30, 60, and 120 after limbal transplantation (GI), and on days 33, 37, 44, 60, 90, and 150 after limbal destruction (GII). Results showed a complete destruction of limbal stem cells with loss of corneal transparency. Limbal transplantation prevented conjunctivalization in grafted area. Corneal vascularization and a 360º corneal conjunctivalization were noted in the control dogs (GII). Corneal transparency was restored from day 60th after surgery. Histological examination did not distinguish the transition between the graft and the normal corneal epithelium at anytime. Goblet cells were found in control animals (GII) on 33, 37, 60, and 150 days, whereas a single grafted dog (GI) presented a few goblet cells on day 60th post-transplantation. Limbal autograft transplantation was effective in restoring corneal clarity with no development of ocular complications.

Pay attention to basic and clinical research of pterygium

Pterygium is one of the most common ocular surface diseases. The pathogenesis of pterygium is unclear, and a guideline for drug therapy and surgical treatment has not been established up to now. Ultraviolet light is the most important etiologic factor of pterygium. Destruction of the limbal epithelium barrier is the most important mechanism of pterygium. The most important histopathogenesis of pterygium is degeneration and proliferation of conjunctiva. This article attempts to sketch the mechanism of pterygium and propose several questions for further investigation, and recommends excision of pterygium combined with conjunctival autograft or amniotic membrane graft or limbal conjunctival autograft as the primary surgical procedure. The study of the pathogenesis and clinical guideline for the diagnosis and treatment of pterygium should be emphasized in order to reduce the occurrence and recurrence of pterygium.

Conjunctival–Limbal Autograft, Amniotic Membrane Transplantation, and Intraoperative Mitomycin C for Primary Pterygium

We evaluated and compared the safety and efficacy of the conjunctival-limbal autograft, amniotic membrane transplantation, and intraoperative application of mitomycin C in 94 patients undergoing primary pterygium surgery and concluded that conjunctival-limbal autografting and amniotic membrane methods were more effective and safer than intraoperative mitomycin C.

Amniotic membrane transplantation or combined with limbal autograft transplantation for the treatment of pterygium

目的 观察单纯羊膜移植与联合自体角膜缘移植治疗翼状胬肉的疗效.方法 将翼状胬肉85例(93眼)随机分成两组,A组44例(45眼)行羊膜移植术,B组41例(48眼)行自体角膜缘移植联合羊膜移植术.术后平均随访2年,比较两组的治愈情况及复发率.结果 A组有4眼复发,其中有3眼是复发性翼状胬肉,复发率8.89%(4/45).B组仅1眼复发,复发率为2.08%(1/48).两组复发率差异有统计学意义(P＜0.05).结论 自体角膜缘移植联合羊膜移植术有利于翼状胬肉术后的眼表重建,临床疗效优于单纯羊膜移植术。

Epithelial ingrowth following surgery of recurrent pterygium

Epithelial ingrowth is a rare but devastating condition of the eye, known to complicate incisional ocular procedures. We report a case of secondary glaucoma due to epithelial ingrowth following limbal conjunctival autograft in a case of recurrent pterygium. To prevent such devastating conditions from occurring dissection of recurrent pterygium demands special care to avoid anterior chamber penetration.

Comparison of Conjunctival Autograft With Amniotic Membrane Transplantation for Pterygium Surgery

To compare the clinical results of conjunctival autograft and amniotic membrane transplantation (AMT) for primary and recurrent pterygium excision. In an effort to determine whether AMT yields acceptable cosmetic results as conjunctival autografting in pterygium surgery, we compared the final cosmetic outcomes of these 2 techniques. We performed a prospective, randomized clinical study of 78 eyes (78 patients) divided into 2 groups. Forty eyes (28 with primary and 12 with recurrent pterygia) received conjunctival limbal autograft (group 1), and 38 eyes (27 with primary and 11 with recurrent pterygia) received AMT (group 2) after extensive removal of pterygium. Mean follow-up time was 16.6 +/- 3.52 months in group 1 and 13.4 +/- 2.08 months in group 2. The results were evaluated by clinical examination and photographing and final appearances were graded from 1 to 4. Grade 4 represented true recurrence, whereas grade 3 indicated unacceptable cosmetic appearance. Recurrence rates of primary, recurrent, and all pterygia in group 1 and group 2 were 3.6%, 16.7%, and 7.5% and 3.7%, 18.2%, and 7.9%, respectively. There was no significant difference in recurrence rates between the 2 groups (P = 1.00 for all). The rates of final appearance as grade 3 were 10.0% in group 1 and 21.1% in group 2, and the difference was statistically significant (P = 0.048). No major complications occurred during the follow-up period. Although better results in the final appearance were achieved using conjunctival autografting than with AMT, AMT can be a useful alternative in pterygium surgery, especially in those patients who may have a limited amount of conjunctiva for future surgeries.

Transplantation of conjunctival limbal autograft and amniotic membrane vs mitomycin C and amniotic membrane in treatment of recurrent pterygium

To compare the efficacy and complications of conjunctival limbal autograft (CLAU) and amniotic membrane transplantation (AMT) vsintraoperative mitomycin C (MMC) and AMT for treatment of recurrent pterygium. Forty eyes of 40 patients with recurrent pterygium underwent CLAU and AMT (20 eyes) or intraoperative MMC (0.02%, 3 min) and AMT (20 eyes). Three eyes (15%) had symblepharon before surgery in each group. Recurrence was compared in each group by using chi(2) test. No major postoperative complications occurred during 6-19 months of follow-up. In CLAU/AMT group, no pterygium recurrence was observed. Recurrence occurred in four eyes (20%) in MMC/AMT group after 3 and 4 months (P-value=0.035, chi(2) test). No recurrence of pterygium or symblepharon was seen in six eyes with recurrent pterygium and symblepharon (three eyes in each group). CLAU with AMT seems to be more effective than intraoperative MMC with AMT for treatment of recurrent pterygium.

Effect of pterygium excision by limbal conjunctival auotografting on tear function tests

We investigated the effects of pterygium excision using the limbal conjunctival autografting technique on the tear function tests in 14 eyes of 13 patients. Since no difference was found in the Schirmer and tear break-up time tests at one and six months postoperative vs preoperative pterygium excision does not affect tear function test results during short-term follow up.

Optische lamellär-perforierende Keratoplastik mit Stammzelltransplantation bei Risikofällen

Stem cells of the corneal epithelium are located mainly at the sclerocorneal limbus, and are essential for the maintenance of a healthy corneal surface. Limbal stem cell deficiency leads--depending on intensity and extension--to several corneal alterations. The appearance of limbal stem cell deficiency is chiefly concentrated on pemphigoids, Herpes relapses and alkali burns and represents the main part of high-risk keratoplasty. The different types of limbal stem cell deficiency (partial or total) are usually treated with several surgical techniques. Total limbal deficiency can be treated with limbal transplantation, either of the healthy eye (limbal autograft), or using material of another donor (limbal allograft). Lamellar-penetrating keratoplasty (L-P-KP) has been carried out in five patients. Unlike recent surgical techniques containing ring-shaped or circular transplantations, a stripe-like lamellar preparation was performed. L-P-KP involves a peripheral lamellar and a central penetrating keratoplasty combined with limbal stem cell transplantation. In four of six cases, the transplant has been successfully kept clear without the occurrence of corneal decompensation or ulceration. No major changes could be seen between pre- and postoperative visual acuity. The mean observation period was 24 months. L-P-KP offers a new surgical opportunity in the treatment of high-risk cases of limbal deficiency.

The Efficiency of Limbal Conjunctival Autografting in Pterygium Surgery

To investigate the efficiency of limbal conjunctival autografting technique in pterygium surgery. Eighty-four eyes of 68 patients with pterygium were treated by simple excision technique and 29 eyes of 24 patients with pterygium were treated by limbal conjunctival autografting technique. The definition of recurrence was fibrovascular tissue over the limbus onto the cornea in the area of previous pterygium excision. The ages of the patients were between 25 and 88. The follow-up periods ranged from 6 to 25 months. The patients treated by simple excision technique were followed up for 6 to 25 (average 15+/-6) months and the patients treated by limbal conjunctival auto-grafting technique were followed up for 7 to 24 (average 17+/-5) months. The recurrence rates were 27% (23 eyes) and 7% (2 eyes), respectively. There was a statistically significant difference in the recurrence rate between the patients who underwent simple excision and those who underwent limbal conjunctival autografting (p=0.016). Limbal conjunctival autografting is an effective surgical technique for the treatment of pterygium. It has a low recurrence rate when compared with the simple excision technique.

Treatment of pterygium with corneal limbal autograft transplantation in 60 cases

目的 探讨胬肉切除联合自体角膜缘移植治疗翼状胬肉的手术效果.方法切除胬肉后用自体角膜缘移植的方式治疗翼状胬肉60例(68眼),术后随访3月～1年.结果随访期内有3眼复发(4.41%),未发现睑球粘连者.结论翼状胬肉切除联合自体角膜缘移植有利于重建角膜缘功能,是一种治疗翼状胬肉有效的手术方法。

Limbal epithelial autograft from below with connectivetissue transplantation in treatment of pterygium

目的 评价下方带蒂角膜缘上皮移植治疗翼状胬肉的效果.方法对18例(22眼)翼状胬肉下方带蒂角膜缘上皮移植手术进行回顾,观察翼状胬肉术前,术后视力变化及复发情况.结果随访时间最长者12月,最短者1月,无1例复发,视力有不同程度提高.结论下方带蒂角膜缘上皮移植较完全游离上皮移植片,具有血供好,易成活,正反面不易错,易固定,术后充血水肿轻,拆线时间缩短。

Ultrastructural analysis of in vivo expanded corneal epithelium on amniotic membrane.

The purpose of this study is to characterize and compare the ultrastructural changes occurring during the in vivo cultivation of corneal epithelium on amniotic membrane (AM) at several different time points. Corneal burn patients (n=7) with a corneal epithelial defect and severe limbal damage were selected. Initially, AM transplantation with limbal autograft was performed at the acute stage of corneal burn to reconstruct the damaged ocular surface. One to six (mean interval; 3.3±1.2) months later, the central part of AM containing an in vivo expanded corneal epithelium was excised and retransplanted in adjacent lesions. The excised epithelium with AM was examined by electron microscopy and immunohistochemical study. By electron microscopy, one and two months after expansion, cultivated epithelium on AM showed an undifferentiated epithelium and an incomplete basement membrane (BM). But, after three months, the cultivated epithelium began to differentiate into a multilayered epithelium with a continuous BM with increased hemidesmosomes. These findings were further confirmed by immunohistochemical study, that cytokeratin K3 was expressed in the cultivated corneal epithelium and newly formed BM was partially positive of collagen IV at three months. At least 3 months may be needed for the proliferation and differentiation of in vivo cultivated corneal epithelium on AM.

The conjunctival limbal autograft( CLAU)combined with amniotic membrane patching (AMP)to treat early severe ocular chemical injury

目的 探讨早期自体结膜角膜缘移植联合羊膜贴敷术治疗早期重度眼部化学伤疗效.方法分别对自体结膜角膜缘移植术和自体结膜角膜缘移植联合羊膜贴敷术两组的疗效进行回顾性分析.结果自体结膜角膜缘移植联合羊膜贴敷组比自体结膜角膜缘移植组角膜上皮修复快,角膜新生血管少,假性胬肉少,视力好.结论早期自体结膜角膜缘移植联合羊膜贴敷术是治疗早期重度眼部化学伤的有效方法。

Clinical observation of corneal limbal autograft for treating recurrent pterygium

目的 观察自体角膜缘干细胞移植术治疗复发性翼状胬肉的临床效果.方法对复发性翼状胬肉27例(30眼)在手术显微镜下行胬肉切除加自体角膜缘干细胞移植术,术后随访6月以上,观察其效果.结果30眼中治愈29眼,治愈率为96.67%;1眼胬肉复发,复发率3.33%.结论角膜缘干细胞移植术能明显减少胬肉手术的复发率。

Visusrehabilitation bei schwersten Veränderungen der Augenoberfläche

Severe ocular surface diseases, such as Stevens-Johnson syndrome, ocular cicatricial pemphigoid or severe ocular burns may result in a significant loss of corneal stem cells, eventually leading to vision impairment or even corneal blindness. In case of unilateral involvement, limbal autografting, by means of transplanting limbal stem cells from the healthy fellow eye, has proved to be an effective procedure for restoring the integrity of the ocular surface. Limbal allografts may be performed in patients with bilateral disease, however, systemic immunosuppression is mandatory in these cases, with a long-term outcome that is frequently reduced compared to limbal autografts due to acute or chronic graft rejection. In recent years, amniotic membrane transplantation has been successfully employed as an additional tool in ocular surface reconstruction. The AlphaCor synthetic cornea, which is made of flexible acrylic may be considered as an alternative in patients with repeated corneal graft failures. Both limbal transplantation and the AlphaCor have been shown to be effective in eyes with an adequate tear film, but are most likely to fail in severe dry eyes or in patients with cicatrising diseases. Such conditions are the domain of keratoprostheses (KPros) with rigid optics, which certainly can be considered as the 'last resort' to restore vision in patients with profound corneal blindness not amenable to conventional corneal and limbal grafting. The osteo-odonto-keratoprosthesis according to Strampelli and modified by Falcinelli makes use of a "biological" support consisting of a longitudinal section of one of the patient's teeth that is also supported by the surrounding alveolar bone tissue. Compared to other devices favourable long-term results have been reported. In patients lacking any usable teeth, implantation of a keratoprosthesis with haptics made of Dacron (Pintucci-KPro) or tibial bone (Temprano-KPro) might be considered.

Survival Analysis of Conjunctival Limbal Grafts and Amniotic Membrane Transplantation in Eyes With Total Limbal Stem Cell Deficiency

To evaluate the survival of conjunctival limbal grafts and amniotic membrane transplantation (AMT) for total limbal stem cell deficiency (LSCD) and the influence of several parameters as cause of LSCD, dry eye, keratinization, eyelid abnormalities, HLA compatibility, systemic immunosuppression, and keratoplasty (PKP) on surgical outcome. Prospective, noncomparative, interventional case series. Thirty-three eyes of 31 patients with total LSCD that underwent conjunctival limbal grafts and AMT at the Department of Ophthalmology, Federal University of São Paulo were included in this study. Cumulative graft survival as well as the influence of several variables on surgical outcome was analyzed. Ten eyes (30%) underwent conjunctival limbal autograft and 23 (70%) underwent conjunctival limbal allograft from living HLA-matched donor. Graft survival was seen in 13 eyes (40%) at 1 year and in 11 eyes (33.3%) at 2 years, with a cumulative survival of 33% after a mean follow-up time of 33 months. Increase in postoperative visual acuity was observed in 20 eyes (60.6%) during this period. Marked impact on graft survival was observed for patients with Stevens-Johnson syndrome, dry eye, keratinization, eyelid abnormalities, and allogeneic conjunctival limbal transplantation (independently of HLA compatibility) (P < .05). Preoperative dry eye was the most important prognostic parameter for surgical outcome (P < .001). Conjunctival limbal grafts associated with AMT are useful for restoring corneal epithelium phenotype in eyes with total LSCD. However, the cumulative survival declines substantially over a 2-year period. Considering all investigated variables, dry eye was the most important prognostic parameter.

Mitomycin C, amniotic membrane transplantation and limbal conjunctival autograft for treating multirecurrent pterygia with symblepharon and motility restriction

Treatment of eyes with multirecurrent pterygia associated with severe symblepharon and motility restriction is challenging. A combined surgical procedure of intraoperative mitomycin C, amniotic membrane transplantation and conjunctival limbal autograft was applied for treating such eyes. Seven eyes of seven patients who had previously undergone an average of four operations for pterygial removal and who manifested recurrent pterygia associated with severe symblepharon and motility restriction were involved in this retrospective study. The surgical procedures involved clearing fibrovascular membrane over the cornea, extensive excision of epibulbar fibrovascular tissue to the bare sclera, application of 0.02% mytomycin C onto the bare sclera for 5 min and transplantation of preserved human amniotic membrane and conjunctival limbal autograft. Postoperatively, all seven eyes showed rapid epithelialization on the corneal surface in 3-5 days and, on the conjunctival surface, in 10-18 days. For a mean follow-up period of 22.4+/-6.1 months, six eyes recovered deep fornices, smooth and stable ocular surface and full ocular motility without recurrence. One eye showed regrowth of fibrovascular tissue and motility restriction but less severe than before surgery. No complication was noted due to mitomycin C. Combined intraoperative mitomycin C, amniotic membrane graft and limbal conjunctival autograft are successful approaches for treating multirecurrent pterygia with severe symblepharon to restore the ocular surface integrity and prevent recurrence.

Efficacy of Systemic Cyclosporine A and Amniotic Membrane on Rabbit Conjunctival Limbal Allograft Rejection

To evaluate the effect of intramuscular cyclosporine A (CsA) and amniotic membrane (AM) on conjunctival limbal allograft survival in a rabbit model. Eighty-two female rabbits (59 New Zealand white rabbits, 23 Dutch pigmented rabbits) were used. The New Zealand white rabbits were divided into 4 treatment groups: group 1 (n=13), conjunctival limbal autograft transplantation; group 2 (n=12), conjunctival limbal allograft transplantation without additional treatment; group 3 (n=18), conjunctival limbal allograft transplantation and human AM; and group 4 (n=16), conjunctival limbal allograft transplantation and systemic CsA (10 mg/kg/day intramuscularly). The 23 Dutch pigmented rabbits were used as limbal stem cell allograft donors. The rejection index, the mean survival time, and the rejection rates were calculated for each group. After 28 days of follow-up, there were no episodes of limbal rejection in groups 1 and 4, whereas the rejection rate was 100% in groups 2 and 3. There was no significant difference in mean survival time of the rejected grafts between groups 2 and 3. A model of rejection of conjunctival limbal transplantation was developed in the rabbit. Intramuscularly injected CsA effectively prevents limbal allograft rejection. Human AM is not useful for this purpose.