Limbal allografting from related live donors for corneal surface reconstruction

OBJECTIVE: To report the results of limbal allograft transplantation, from human leukocyte antigen (HLA)-matched and -unmatched related live donors, in patients with ocular surface disease due to chemical burns and Stevens-Johnson syndrome. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Eight patients (nine eyes) with severe chemical burns (n = 7 eyes) and Stevens-Johnson syndrome (n = 2 eyes). INTERVENTION: Recipient eyes were treated with excision of cicatricial tissues. Transplantation of superior and inferior limbal grafts was performed from related live HLA-matched (n = 7) and -unmatched donors (n = 2). Systemic cyclosporine was not used in any of the recipients. MAIN OUTCOME MEASURES: Reconstruction of corneal surface epithelium, restoration of avascularity, increase in ocular comfort, and improvement in visual acuity. RESULTS: With a mean observation period of 17.2 months, phenotypically corneal epithelium, decreased vascularization of the corneal surface, and improved ocular comfort were seen in seven (77.8%) eyes. In all seven eyes, gradual recurrence of peripheral corneal vascularization occurred during the follow-up period. Features of graft rejection developed in three (42.9%) of these seven eyes. In two eyes, limbal transplantation from HLA-unmatched donors failed to reconstitute the corneal surface. Limbal allograft transplantation resulted in visual acuity of 20/400 or greater in only two (22.2%) eyes at last follow-up. Corneal grafts performed 7 and 16 months after successful limbal transplantation in two eyes developed recurrent epithelial breakdown and superficial corneal scarring. None of the donor eyes in this study had any complication. CONCLUSION: Transplantation of limbal tissue from related live donors successfully reconstructs the corneal surface in HLA-matched recipients. Recurrence of vascularization on long-term follow-up probably results from inadequate stem cell transfer, immune-mediated stem cell damage, or both. Limbal allografting is best performed by transplanting the entire limbus from a cadaveric donor eye with systemic immunosuppression of the recipient, even if the donor is HLA-compatible.     

Limbal graft and/or amniotic membrane transplantation in the treatment of ocular burns

Limbal stem cell transplantation (LSCT) and amniotic membrane transplantation may improve corneal recovery after a chemical burn. Amniotic membrane was applied as a patch in 5 eyes; LSCT from healthy contralateral eye was performed in 6 eyes, and a combination of these techniques was performed in 4 eyes. There were no complications during surgical procedure. Epithelization was completed after 2 weeks in patients with LSCT, and after 3 weeks in the amniotic membrane transplantation group. Visual acuity improved in all patients. No complication was observed on either the donor or the recipient eye during a follow-up period of >13 months in all groups. Amniotic membrane is effective in promoting re-epithelization and reducing inflammation when applied alone in patients with 3- to 6-hour limbal involvement, as well as combined with LSCT in patients with >6-hour limbal ischemia. LSCT is an effective procedure for rehabilitation after severe chemical trauma of the eye with more than 50% limbal involvement.     

Amniotic membrane transplantation for partial and total limbal stem cell deficiency secondary to chemical burn

PURPOSE: To evaluate the surgical outcome of preserved amniotic membrane transplantation (AMT) for ocular surface reconstruction in chemical burn with limbal stem cell deficiency. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Twenty eyes of 20 consecutive patients with limbal stem cell deficiency secondary to ocular chemical injury. INTERVENTION: AMT with or without adjunctive limbal transplantation using limbal tissue from either the healthy contralateral eye (CLAU) or a living related donor (lr-CLAL). MAIN OUTCOME MEASURES: Reconstruction of corneal epithelium (clear appearance without epithelial defect, normal fluorescein permeability and the absence of conjunctiva-derived goblet cells on impression cytology), decrease in corneal vascularization and improvement in visual acuity. RESULTS: With a mean follow-up time of 19 months (range, 8-27 months), satisfactory ocular surface reconstruction was obtained in 15 eyes (75%), with reduced inflammation and vascularization of the ocular surface and a mean epithelialization time of 3.3 weeks. Success was observed in all cases of partial limbal stem cell deficiency (PLD) and in 68.75% (11 eyes) of cases of total limbal stem cell deficiency (TLD). Surgical failure was observed in five severe cases (31.25%). A significant visual improvement was observed in all cases after surgery, except for 2 eyes that maintained preoperative visual acuity. CONCLUSIONS: AMT seems to be an efficient adjunct for ocular surface reconstruction in chemical burns with PLD. When performed in conjunction with limbal stem cell transplantation, it is also effective in most cases of TLD.     

Long-term outcomes of donor eyes after conjunctival limbal autograft and allograft harvesting

ObjectiveTo investigate the ocular surface stability of donor eyes after conjunctival limbal autograft (CLAU) or conjunctival limbal allograft (CLAL).DesignRetrospective interventional case series.ParticipantsPatients diagnosed with limbal stem cell deficiency (LSCD) who underwent ocular surface stem cell transplantation with postoperative follow-up of at least 3 months.MethodsDonor eye data collected included preoperative and postoperative Snellen best-corrected visual acuity (BCVA), intraoperative and postoperative complications, re-epithelialization times, and ocular surface stability at the last follow-up.ResultsSixteen donor eyes of 16 patients were included, the mean age at the time of surgery was 59.3 years, and the mean follow-up period was 53 months. The most common injury etiology was chemical injury, followed by iatrogenic causes and Stevens-Johnson syndrome, then congenital aniridia. Eleven patients underwent CLAU, 3 underwent living-related CLAL, and 2 underwent CLAL combined with keratolimbal allograft. Preoperative mean donor eye BCVA was 0.22 ± 0.32 logMAR (Snellen equivalent ≈ 20/33), and mean BCVA at the last follow-up was 0.18 ± 0.24 logMAR (Snellen equivalent ≈ 20/30) (p = 0.4). All donor eyes had a stable ocular surface at the last follow-up, with no signs of iatrogenic LSCD or delayed corneal epithelial healing. There were no intraoperative or postoperative complications such as infections, persistent epithelial defects, corneal neovascularization, or chronic inflammation.ConclusionThis study provides additional evidence for the long-term safety of donor eyes when providing limbal stem cell tissue for CLAU or CLAL.     

Simple limbal epithelial transplantation (SLET): a novel surgical technique for the treatment of unilateral limbal stem cell deficiency

This study describes a novel surgical technique of limbal transplantation, which combines the benefits of existing techniques while avoiding their difficulties. Six patients with unilateral and total limbal stem cell deficiency following ocular surface burns underwent a single-stage procedure. A 2 × 2 mm strip of donor limbal tissue was obtained from the healthy eye and divided into eight to ten small pieces. After surgical preparation of the recipient ocular surface, these tiny limbal transplants were distributed evenly over an amniotic membrane placed on the cornea. After surgery, a completely epithelialised, avascular and stable corneal surface was seen in all recipient eyes by 6 weeks, and this was maintained at a mean ± SD follow-up of 9.2 ± 1.9 months. Visual acuity improved from worse than 20/200 in all recipient eyes before surgery to 20/60 or better in four (66.6%) eyes, while none of the donor eyes developed any complications. This technique requires less donor tissue than previously used for conventional autografting and does not need a specialist laboratory for cell expansion. Although long-term results are awaited, this simple limbal epithelial transplantation promises to be an easy and effective technique for treating unilateral limbal stem cell deficiency following ocular burns.     

Automatized large diameter lamellar keratoplasty and stem cell transplantation for the treatment of ocular surface diseases with limbal insufficiency

PURPOSE: To report a new surgical procedure for the treatment of ocular surface diseases associated with severe limbal insufficiency. METHODS: A retrospective review of four patients with severe ocular surface disease who required stem cell transplantation and keratoplasty for the correction of limbal insufficiencies. They underwent large diameter lamellar keratoplasty with microkeratome. When limbal dysfunction was associated with limited alteration of the ocular surface and transparent deep corneal stroma only the anterior corneal stroma was transplanted. When the entire corneal thickness was compromised, both anterior and deep donor buttons were transplanted. RESULTS: Patients remained stable and improved their visual acuity after surgery. Best-corrected visual acuity ranged from 20/200 to 20/30. No corneal graft rejections were found. The main complication found in one of our patients was a central stromal opacity which required a secondary penetrating keratoplasty. CONCLUSIONS: Automatized large diameter lamellar keratoplasty provides a safe and successful alternative to limbal transplantation for limbal insufficiency associated with corneal opacity. This technique enables a single-stage surgical procedure and the use of a single donor which reduces the risk of rejection. In addition, better refractive results are achieved due to the quality of the interface and the absence of corneal sutures.     

Amniotic membrane transplantation with conjunctival limbal autograft for total limbal stem cell deficiency

PURPOSE: To evaluate the outcomes of corneal surface reconstruction with conjunctival limbal autograft when combined with amniotic membrane transplantation on both the donor and recipient eyes. DESIGN: Retrospective, noncomparative, interventional small case series. PARTICIPANTS: Five eyes of five patients with total limbal stem cell deficiency (LSCD) resulting from pseudopemphigoid (n = 1), chemical burns (n = 3), and extensive removal of conjunctival intraepithelial neoplasia (n = 1) were operated on by one surgeon (SCGT). INTERVENTION: After the removal of fibrovascular pannus from the corneal surface, two conjunctival limbal free grafts were harvested from the fellow eyes in all five patients with unilateral LSCD. Amniotic membrane, with the basement membrane side up, was grafted onto the defect created at the donor site and onto the recipient corneal and limbal sclera before placement of conjunctival limbal grafts. MAIN OUTCOME MEASURES: Symptomatic relief, improvement in visual acuity, fornix deepening, and rapid healing and restoration of normal cornea and limbus in the recipient and donor eyes were assessed. RESULTS: During the mean follow-up of 22 months (range, 11-48 months), all eyes experienced symptomatic relief. All recipient eyes had a mean improvement in visual acuity of nine lines (range, 7-12). The three eyes with stromal vascularization showed regression, and all recipient eyes had marked improvement in corneal clarity. Three eyes receiving simultaneous symblepharon lysis and fornix reconstruction successfully regained deep, stable fornices. The donor eyes showed rapid healing and restoration of the normal limbal landmark, even in one eye where nearly the entire limbus was removed. CONCLUSIONS: Limbal conjunctival transplantation is an effective procedure for restoring the corneal surface integrity in eyes with total LSCD. The additional use of amniotic membrane may contribute to a higher rate of success in the recipient eye and a lower rate of complications in the donor eye, as well as allow the simultaneous correction of concomitant cicatricial abnormalities.     

深低温保存异体角膜缘干细胞羊膜移植治疗重度眼表疾病

目的 应用以羊膜为载体的深低温保存的角膜缘干细胞同种异体移植术治疗重度眼表疾病。方法 19例19眼重度眼表疾病患者采用羊膜移植联合深低温保存的角膜缘干细胞同种异体移植，2例术后半年行穿透性角膜移植术，随访观察术后疗效。结果 14例平均随访超过一年，眼表结构恢复正常，整个角膜上皮未见结膜杯状细胞，保存了眼球，视力均有不同程度的提高；1例植片脱落；4例发生角膜自溶的免疫排斥反应。结论 羊膜移植联合深低温保存的角膜缘干细胞同种异体移植术对于重度眼表疾病患者能快速、稳定的促进角膜表面重新上皮化，是一项可采纳的技术。     

亲属供体角膜缘移植治疗化学烧伤致角膜缘衰竭的初步疗效

目的 探讨亲属供体角膜缘干细胞移植治疗化学伤引起的角膜缘干细胞衰竭的疗效和并发症.方法 回顾性对照病例研究.2006年4月至2007年12月中山大学中山眼科中心对12例(12只眼)化学伤引起的角膜缘干细胞衰竭连续病例,使用人类白细胞抗原(HLA)匹配(10例)或不匹配(2例)的亲属供体行角膜缘移植,并与同期施行异体角膜缘移植的15例化学伤性角膜缘衰竭患者比较.行亲属供体角膜缘移植的后8例患者和全部异体角膜缘移植的患者术后均全身使用环胞素A.术后观察上皮愈合、新生血管、角膜透明度及视力等.随访12～27个月.两组间术后角膜上皮化时间的差异采用t检验,两组间眼表重建成功率、新生血管复发率及植片排斥率的差异采用卡方检验.结果 亲属供体角膜缘移植组有10只眼(83.3%)于术后(9.6±3.4)d角膜上皮愈合,9只眼(75.0%)术后恢复了稳定的眼表;术后5～8个月,成功重建眼表的9只眼中有7只眼(77.8%)出现角膜周边部新生血管复发.而异体角膜缘移植组有12只眼(80.0%)于术后(11.2±4.6)d角膜上皮愈合,7只眼(46.7%)术后恢复了稳定的眼表;术后4～10个月,成功重建眼表的7只眼全部出现角膜周边部新生血管复发.两组术后上皮愈合率和愈合时间比较,差异均无统计学意义(χ2=1.764,P=0.117;t=0.116,P=0.133);但眼表重建成功率和术后远期新生血管复发率比较,差异均有统计学意义(χ2=4.158,P=0.015;χ2=3.463,P=0.022).在成功重建眼表的患者中,亲属供体角膜缘移植组术后有2例出现植片排斥,其中1例发生在HLA匹配的受体,另1例发生在HLA不匹配的受体;而异体角膜缘移植组有3例出现植片排斥.所有供体眼术后均未出现并发症.结论 亲属供体角膜缘移植可有效地重建眼化学伤患者的眼表.使用HLA匹配的供体,并全身使用环胞素A,能有效减少术后植片排斥,延长植片的存活.     

Amniotic membrane transplantation for reconstruction of corneal epithelial surface in cases of partial limbal stem cell deficiency

PURPOSE: To assess the efficacy of amniotic membrane for treatment of partial limbal stem cell deficiency (LSCD). METHODS: Medical records of four patients with partial LSCD who underwent pannus resection and amniotic membrane transplantation (AMT) were reviewed for ocular surface stability and improvement in visual acuity. Clinico-histopathological correlation was done with the resected pannus tissue. RESULTS: All the eyes exhibited stable corneal epithelial surface by an average of 7 weeks postoperatively with improvement in subjective symptoms. Best corrected visual acuity improved from preoperative (range: 6/9p-6/120) to postoperative (range: 6/6p-6/15) by an average of 4.5 lines on Snellen visual acuity charts. Histopathological examination of excised tissue showed features of conjunctivalisation. CONCLUSION: Amniotic membrane transplantation appears to be an effective means of reconstructing the corneal epithelial surface and for visual rehabilitation of patients with partial limbal stem cell deficiency. It may be considered as an alternative primary procedure to limbal transplantation in these cases.     

Ocular surface reconstruction for thermal burns caused by fireworks

PURPOSE: To describe 6 eyes with severe firework-related ocular surface injuries that were treated by limbal stem cell transplantation combined with amniotic membrane transplantation (AMT). METHODS: Six eyes of 6 patients with firework-related ocular injuries were retrospectively studied. All subjects were men, with age ranging from 9 to 26 years. All patients were in chronic stage of thermal injury, and all had total limbal stem cell dysfunction and subsequent conjunctival fibrosis. They had limbal stem cell transplantation (1 had an allograft and 5 had autograft transplantation) combined with AMT to restore vision. Mitomycin C was used in 1 eye intraoperatively. RESULTS: After ocular surface reconstruction using limbal stem cell transplantation combined with AMT, corneal epithelialization was achieved in 4 eyes after a mean duration of 20.8 +/- 12.2 days (range, 4-33 days). After a mean follow-up period of 36 months (range, 5-87 months), marked reduction of fibrosis was noted in all eyes. At last examination, the corneal surface was covered by corneal-phenotype epithelium in 4 eyes, and the remaining 2 eyes had conjunctivalization. The cornea was optically clear in 3 eyes, with corrected visual acuity of 20/100 in these 3 eyes. Both eyes that developed conjunctivalization had massive fibrosis preoperatively and severe eyelid deformities. CONCLUSION: Although severe firework-related ocular surface injuries were difficult to treat, limbal stem cell transplantation combined with AMT enable some success in cosmetic and visual outcome. Management of eyelid abnormalities and ocular surface fibrosis seemed to be a key to success in visual rehabilitation.     

早期行保存板层角巩膜联合干细胞植治疗眼严重碱烧伤的临床观察

目的评价早期行保存板层角巩膜移植联合干细胞移植治疗眼严重碱烧伤的疗效。方法将符合Roper-Hall诊断标准Ⅲ～Ⅳ度的眼部碱烧伤患者共28例32眼在受伤二周内行保存板层角巩膜移植联合干细胞移植术。结果随访3～36个月,术后视力提高者18眼(56.2%,18/32),未提高者10眼,下降者4眼。角膜植片透明14眼,透明率43.7%(14/32)。无一眼发生角膜溃疡穿孔。结论对眼严重碱烧伤的患者行早期清创合并保存板层角巩膜移植联合干细胞移植术,可有效减少角膜溃疡穿孔、角膜血管化,提高视力。     

Deep anterior lamellar keratoplasty combined with autologous limbal stem cell transplantation in unilateral severe chemical injury

PURPOSE: To evaluate the efficacy of deep anterior lamellar keratoplasty combined with autologous limbal stem cell transplantation for ocular surface reconstruction and visual rehabilitation in eyes with unilateral, late-stage, severe chemical injury. METHODS: This was a retrospective, noncomparative, interventional case series that included 7 eyes of 7 patients, with severe unilateral late stage chemical injury, exhibiting corneal vascularization, conjunctivalization, and extensive corneal scarring were treated at the C. J. Shah Cornea Service, Sankara Nethralaya, a tertiary care center. Surgical procedures included releasing symblepharon adhesions, excising epibulbar fibrous tissue, superficial keratectomy to remove fibrovascular tissues over cornea, deep anterior lamellar dissection, grafting a lamellar corneal button, and transplanting autologous limbal graft, with or without amniotic membrane transplantation. The main outcome measures were relief of patient symptoms, postoperative recovery of the ocular surface, corneal clarity, corneal epithelial stability, and best corrected visual acuity. RESULTS: The mean duration between the injury and surgery was 24.4 +/- 21.8 months. No intraoperative complications were noted. Successful epithelialization was achieved in all eyes. The reconstructed corneal surface remained stable during the entire follow-up period (mean follow-up, 16.57 +/- 5.12 months). All patients had resolution of ocular symptoms. Remarkable improvement in vision was noted in all (85.7%) except 1 eye in which recovery was limited due to amblyopia. The average best corrected visual acuity at last follow-up was 20/50. No complications were noted in the donor fellow eye. CONCLUSIONS: DALK combined with autologous limbal transplantation can restore a healthy, stable ocular surface, besides providing a clear cornea that remarkably improves the visual acuity, in patients with unilateral, late stage, severe chemical injury.     

活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失(英文)

目的:评价利用活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失的临床效果。方法:从2005-07/2007-12,本研究包括了9名男性化学性眼外伤患者(10眼)。所有患者接受了亲属活体异体结膜缘和羊膜移植,2例眼接受了睑缝术。用环孢菌素和泼尼松龙进行全身性免疫抑制。结果:在3例眼中观察到完全角膜上皮化(30%),其中1例在术后1.5mo出现免疫排斥,角膜溶解引起穿孔,加大全身性免疫抑制剂量来控制病情。3例眼中植片无法在角膜表面重新形成上皮,被定为原发性失败。其余4眼有部分上皮形成,但上皮细胞无法完全覆盖角膜表面。术前最佳矫正视力从手动到1m处数指,术后最佳矫正视力从光感到20/80。有5眼视力得到改进,不需其他治疗。手术失败的主要原因为干眼症和持续性炎症。结论:对于能控制泪量和眼部炎症的病例,亲属活体异体角膜缘和羊膜移植是治疗化学性眼外伤造成的角膜缘干细胞缺失最佳方法之一。     

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.     

Limbal stem cell transplantation for the treatment of subepithelial amyloidosis of the cornea (gelatinous drop-like dystrophy)

PURPOSE: Subepithelial amyloidosis of the cornea, or gelatinous drop-like corneal dystrophy (GDD), is a severe form of corneal stromal amyloidosis predominantly found in the Japanese population. GDD causes severe visual disturbances with irritating symptoms, and keratoplasty is inevitably complicated by early recurrence. This study was conducted to evaluate the efficacy of limbal stem cell transplantation (LSCT) for the treatment of GDD. METHODS: Nine consecutive eyes of seven patients with GDD were treated with LSCT. Limbal grafts were obtained from cadaver eyes. All eyes underwent lamellar or penetrating keratoplasty simultaneously with LSCT. Intensive epithelial management and immunosuppression therapy was performed. RESULTS: With a mean observation period of 4 years, eight (88.9%) of nine eyes did not show any signs of recurrence. Five grafts remained clear, and seven eyes had an improvement in vision. Glaucoma and rejection were observed in five and three eyes, respectively, and two eyes with glaucoma required surgical intervention. CONCLUSIONS: Limbal stem cell transplantation is effective for the prevention of recurrence in GDD. Control of intraocular pressure and rejection are the keys to long-term maintenance of clear grafts.     

Ex vivo expansion of corneal limbal epithelial/stem cells for corneal surface reconstruction

PURPOSE: The management of severe ocular surface disease due to limbal stem cell deficiency has changed dramatically. The concept of limbal stem cells, as the source of corneal epithelium revolutionised the therapeutic approach of ocular surface reconstruction. Deficiency of limbal stem cells results in blinding ocular surface diseases. Grafting viable limbal tissue, from either fellow healthy eye or a donor eye, with the resident stem cell population may replenish limbal stem cells and can restore the corneal surface to normality. Transplanting the limbal tissue can be achieved through a variety of procedures that include cadaveric keratolimbal allograft (KLAL), live or living related conjunctival limbal allograft (Ir-CLAL) and limbal autograft. Advances in tissue engineering techniques have offered a viable alternative to overcome the limitation of limbal tissue available for transplantation. Epithelial stem cells harvested from a small limbal biopsy can be expanded in vitro on a suitable carrier and then transplanted to the diseased cornea to successfully restore the corneal surface. This article is a chronological review of the important steps that brought ex vivo expanded stem cell transplantation in ocular, particularly corneal surface reconstruction. METHODS: The MEDLINE data base was searched for the years 1966-2002, using key words cornea, cell culture, ex-vivo expansion, limbus, stem cell, ocular surface and transplantation. Several articles that were not found by MEDLINE search were taken from references from other articles. Inclusion or exclusion of article was based on the relevance to the subject. CONCLUSIONS: Corneal epithelial reconstruction with ex vivo expanded limbal cells is a potential tool in ocular surface reconstruction, although the technique is currently investigational. Strategies to achieve conjunctival epithelial restoration and tear film replenishment will allow ophthalmic surgeons to truly reconstruct the ocular surface.     

Treatment of unilateral limbal stem cell deficiency syndrome by limbal autograft]

PURPOSE: To evaluate the improvement of the ocular surface after limbal autograft in patients with unilateral limbal stem cell deficiency related to chemical burns. MATERIALS AND METHODS: Limbal autograft was performed in five patients with unilateral limbal stem cell deficiency related to chemical burns. Thereafter, four patients underwent penetrating keratoplasty. The limbal graft was obtained from the fellow eye, and was secured with interrupted sutures. Patient follow-up ranged from 10 to 47 months. Limbus and corneas were studied by means of light microscopy. RESULTS: All five patients reported subjective improvement. Vascularization decreased in one cornea. Visual acuity improved in one eye and did not change in the remaining four eyes. After penetrating keratoplasty, graft reepithelialization was achieved after respectively 3, 4, 21, and 30 days. Light microscopy showed the presence of goblet cells in the limbal epithelium in four cases. After limbal autograft, the corneal epithelium was devoid of goblet cells in three out of four cases. CONCLUSION: Limbal autograft improves the ocular surface and the prognosis of subsequent penetrating keratoplasty in patients with unilateral limbal stem cell deficiency related to chemical burn.     

Allogenic cultivated limbal stem cell transplantation versus cadaveric keratolimbal allograft in ocular surface disorder: 1-year outcome

Purpose

To compare the outcome of allogenic ex vivo cultivated limbal stem cell transplantation (LSCT) versus cadaveric keratolimbal allograft in patients with limbal stem cell deficiency (LSCD).

Methods

In this prospective interventional study from Army Hospital Research and Referral in New Delhi, 50 eyes of 40 patients with ocular surface disorder having LSCD underwent either cultivated LSCT (group 1: 25 eyes of 20 patients) or keratolimbal allograft transplantation (group 2: 25 eyes of 20 patients). The outcome measures were gain of two or more lines of best-corrected visual acuity (BCVA), absence of conjunctival vascularization over cornea, corneal neovascularization regression, regression of visually significant corneal opacity (iris details poorly visible), Schirmer’s 1 ≥10 s, tear break-up time (TBUT) ≥10 s, and absence of fluorescein staining.

Results

At 1 year of follow-up, both groups experienced significant improvement in all outcome measures, but there was no significant difference between both groups in improvement of two or more lines of BCVA (P = 0.841), absence of conjunctival vascularization over cornea (P = 0.812), corneal neovascularization (P = 0.074), visually significant corneal opacity (P = 0.075), Schirmer’s 1 ≥10 s (P = 0.814), TBUT ≥10 s (P = 0.382), or absence of fluorescein stain (P = 1.00).

Conclusion

Both allogenic ex vivo cultivated LSCT and cadaveric keratolimbal allograft transplantation are comparable in terms of visual gain and ocular surface restoration.

     

Cultivated corneal epithelial stem cell transplantation in ocular surface disorders

PURPOSE: To investigate the outcome of cultivated corneal epithelial transplantation for severe stem cell deficiencies using denuded amniotic membrane (AM) as a carrier. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Thirteen eyes of 11 patients were studied. These consisted of five eyes with acute Stevens-Johnson syndrome (SJS), two with chronic SJS, one with an acute chemical injury, two with chronic chemical injuries, two with ocular cicatricial pemphigoid, and one with drug-induced pseudopemphigoid. All of these eyes had total stem cell deficiencies. MAIN OUTCOME MEASURES: Adaptation of the cultivated corneal epithelium onto the host corneal surface was confirmed 48 hours after surgery. The reconstruction of the ocular surface and visual acuity were measured. METHODS: Corneal limbal epithelium from donor corneas was cultivated for 4 weeks on a denuded AM carrier, with 3T3 fibroblast coculture and air lifting. The cultivated corneal epithelium showed four to five layers of stratification and was well differentiated. After conjunctival tissue removal from the cornea up to 3 mm outside the limbus and subconjunctival tissue treatment with 0.04% mitomycin C, cultivated allocorneal epithelium, including the AM carrier, was transplanted onto the corneal surface up to the limbus. Lamellar keratoplasty, using preserved donor graft without epithelium, was performed simultaneously for five chronic-phase patients showing corneal stromal scarring. Systemic immunosuppression was used to prevent allograft rejection. RESULTS: In all 13 eyes, the entire corneal surface, on which cultivated allocorneal epithelium had been placed, was free from epithelial defects 48 hours after surgery, indicating complete survival of the transplanted corneal epithelium. Visual acuity improved in all eyes after surgery, and 10 of the 13 eyes were restored to good vision (postoperative visual acuity improved two or more lines) 6 months after the operation. During the follow-up period (mean +/- standard deviation, 11.2 +/- 1.3 months), the corneal surfaces were clear, although three eyes experienced epithelial rejection. CONCLUSIONS: Cultivated corneal epithelial transplantation using denuded AM as a carrier can be used for severe stem cell deficiencies.