Background： The limiting factor to corneal transplantation is the availability of donors. Research has suggested that xenogenic acellular corneal scaffolds （XACS） may be a possible alternative to transplantation. T...Background： The limiting factor to corneal transplantation is the availability of donors. Research has suggested that xenogenic acellular corneal scaffolds （XACS） may be a possible alternative to transplantation. This study aimed to investigate the viability of performing lamellar corneal transplantation （LCT） in rabbits using canine XACS. Methods： Fresh dog corneas were decellularized by serial digestion, and LCT was performed on rabbit eyes using xenogeneic decellularized corneal matrix. Cellular and morphological changes were observed by slit-lamp, light, and scanning electron microscopy at 7, 30 and 90 days postoperatively, lmmunocytochemical staining for specific markers such as keratin 3, vimentin and MUC5AC, was used to identify cells in the graft. Results： Decellularized xenogenic corneal matrix remained transparent for about l-month after LCT. The recipient cells were able to survive and proliferate into the grafts. Three months after transplantation, grafts had merged with host tissue, and graft epithelialization and vascularization had occurred. Corneal nerve fibers were able to grow into the graft in rabbits transplanted with XACS. Conclusions： Xenogenic acellular corneal scaffolds can maintain the transparency of corneal grafts about 1-month and permit growth of cells and nerve fibers, and is, therefore, a potential substitute or carrier for a replacement cornea.展开更多
Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on d...Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.展开更多
Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases requir...Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases require surgical intervention.This review provides an update on the current treatment modalities of corneal surgery available for the management of advanced corneal ectasias.展开更多
目的观察带环形巩膜瓣的全角膜板层移植术治疗角膜表面衰竭的临床效果。方法移植带宽6 mm 球结膜和4 mm 板层巩膜的全角膜板层植片,治疗7例(7眼)陈旧性化学伤及热烧伤造成的角膜表面衰竭。结果 7例角膜表面衰竭患者均Ⅰ期愈合,视力提高;...目的观察带环形巩膜瓣的全角膜板层移植术治疗角膜表面衰竭的临床效果。方法移植带宽6 mm 球结膜和4 mm 板层巩膜的全角膜板层植片,治疗7例(7眼)陈旧性化学伤及热烧伤造成的角膜表面衰竭。结果 7例角膜表面衰竭患者均Ⅰ期愈合,视力提高;5例发生结膜排斥反应,3例发生角膜排斥反应,均痊愈;全角膜板层植片1 wk 后逐渐透明,2个月左右层间长入新生血管;随访6个月～5年,平均24.5月,无角膜结膜化及假性翼状胬肉发生;眼表结构稳定,视力0.1～0.5者6例,0.6者1例。结论带环形巩膜瓣的全角膜板层移植术是治疗角膜表面衰竭的重要手段。展开更多
文摘Background： The limiting factor to corneal transplantation is the availability of donors. Research has suggested that xenogenic acellular corneal scaffolds （XACS） may be a possible alternative to transplantation. This study aimed to investigate the viability of performing lamellar corneal transplantation （LCT） in rabbits using canine XACS. Methods： Fresh dog corneas were decellularized by serial digestion, and LCT was performed on rabbit eyes using xenogeneic decellularized corneal matrix. Cellular and morphological changes were observed by slit-lamp, light, and scanning electron microscopy at 7, 30 and 90 days postoperatively, lmmunocytochemical staining for specific markers such as keratin 3, vimentin and MUC5AC, was used to identify cells in the graft. Results： Decellularized xenogenic corneal matrix remained transparent for about l-month after LCT. The recipient cells were able to survive and proliferate into the grafts. Three months after transplantation, grafts had merged with host tissue, and graft epithelialization and vascularization had occurred. Corneal nerve fibers were able to grow into the graft in rabbits transplanted with XACS. Conclusions： Xenogenic acellular corneal scaffolds can maintain the transparency of corneal grafts about 1-month and permit growth of cells and nerve fibers, and is, therefore, a potential substitute or carrier for a replacement cornea.
基金Supported by The Ophthalmic Research Center,Shahid Beheshti University of Medical Sciences,Tehran,Iran
文摘Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.
文摘Keratoconus is a disease characterized by progressive thinning,bulging,and distortion of the cornea.Advanced cases usually present with loss of vision due to high irregular astigmatism.A majority of these cases require surgical intervention.This review provides an update on the current treatment modalities of corneal surgery available for the management of advanced corneal ectasias.
文摘目的观察带环形巩膜瓣的全角膜板层移植术治疗角膜表面衰竭的临床效果。方法移植带宽6 mm 球结膜和4 mm 板层巩膜的全角膜板层植片,治疗7例(7眼)陈旧性化学伤及热烧伤造成的角膜表面衰竭。结果 7例角膜表面衰竭患者均Ⅰ期愈合,视力提高;5例发生结膜排斥反应,3例发生角膜排斥反应,均痊愈;全角膜板层植片1 wk 后逐渐透明,2个月左右层间长入新生血管;随访6个月～5年,平均24.5月,无角膜结膜化及假性翼状胬肉发生;眼表结构稳定,视力0.1～0.5者6例,0.6者1例。结论带环形巩膜瓣的全角膜板层移植术是治疗角膜表面衰竭的重要手段。
