THE MANAGEMENT OF EPITHELIAL INGROWTHAFTER LASER IN SITU KERATOMILEUSIS

Objective. To investigate the treatment of corneal epithelial ingrowth with flap melt after LASIK. Patients and method. Thirteen eyes of 13 patients with corneal epithelial ingrowth and flap melt after LASIK were treated based on the thickness and the extent of melting of the flap. Nine eyes were treated by lifting the flap and scraping the epithelium in the interface. Three eyes underwent allogenic keratomileusis. The flap was removed in one eye. Results. Recurrence occurred in 2 eyes treated by lifting the flap. The flaps, however, healed normally after retreatment. The grafts healed normally in the allogenic keratomileusis group, except for one eye in which the flap was lost. The corneal epithelium healed over the stromal bed after the flap was removed. Corneal haze of grade 2 was present at 6 months. The uncorrected visual acuity was between 0.3 and 1.0, and the best corrected visual acuity lost 1 to 3 lines. Conclusions. Corneal epithelial ingrowth with flap melt is a severe complication after LASIK. However, with proper treatment, vision can be salvaged in most cases.

A study of chitosan blend film as a carrier of corneal endothelial cells

In order to evaluate the cytocompatibility and biocompatibility of a new kind of chitosan blend film as a carrier of corneal endothelial cell, rabbit corneal endothelial cells cultured in vitro were breeded onto the film. After a cell monolayer formed, the scanning electron micrography was performed. After inplanted into anterior chamber, slit lamp observation, thickness metering, specular microscopy and HE staining were performed at random time after operation to evaluate the biocompatibility. Inflmmnation in anterior, thickness of cornea, cell density, hexagonality and cell size of the surgical cornea were taken as the indexes of biocompatibility. The cultured cells exhibited a confluent monolayer 10 days after incubation, which proved the satisfactory cytocompatibility of this film. Biocompatibility assay results suggested the implantation feasibility of the film as a carder of corneal endothelial cells.

应用封闭式Dexsol基质保存角膜的研究

应用自制的 Dexsol 基质保存角膜,对40只动物(兔、猴各20只)角膜及5只人角膜进行了实验研究。保存时间为4℃者2周,34℃者5周。对保存在不同时间及不同温度的角膜应用锥蓝及茜素红双重染色,角膜内皮细胞活性良好。透射及扫描电镜观察保存2周(4℃)及4周(34℃)的角膜内皮细胞超微结构均无病理性改变。应用 Dexsol 基质保存的兔角膜进行同种穿透角膜移植,术后2个月,植片透明。20例接受 Dexsol 基质保存的供体角膜移植的患者,术后3个月移植片透明。植片中央部角膜内皮细胞密度平均为1915个/mm^2。

Expression of carbonic anhydrase Ⅳ in rabbit corneal endothelial cells

Objective To demonstrate the molecular expression of carbonic anhydrase Ⅳ (CA Ⅳ) in rabbit corneal endothelium.Methods Reverse transcriptase polymerase chain reaction (RT-PCR) was performed using cultured and fresh rabbit corneal endothelial total RNA and specific primers for CA Ⅳ. The RT-PCR product was subcloned and sequenced. Immunoblotting and indirect immunofluorescence staining were performed to detect protein expression and distribution of CA Ⅳ using fresh and cultured rabbit corneal endothelium and rat anti-CA Ⅳ polyclonal antibody. Results RT-PCR screening gave positive bands at the predicted size for CA Ⅳ from fresh and cultured rabbit corneal endothelium. Sequencing further confirmed the identity of CA Ⅳ in corneal endothelium. Immunoblotting analysis showed a single band at 52 kDa for freshly isolated and cultured endothelial cells. Indirect immunofluorescence staining revealed an apparent positive staining in cultured endothelial cells.Conclusion Carbonic anhydrase Ⅳ is expressed in rabbit corneal endothelium, which could contribute to the transendothelial HCO 3 - flux that is necessary to maintain corneal hydration and transparency.

Therapeutic efficiency of tissue-engineered human corneal endothelium transplants on rabbit primary corneal endotheliopathy

To evaluate the therapeutic efficiency of tissue-engineered human corneal endothelia (TE-HCEs) on rabbit primary corneal endotheliopathy (PCEP),TE-HCEs reconstructed with monoclonal human corneal endothelial cells (mcHCECs) and modified denuded amniotic membranes (mdAMs) were transplanted into PCEP models of New Zealand white rabbits using penetrating keratoplasty.The TE-HCEs were examined using diverse techniques including slit-lamp biomicroscopy observation and pachymeter and tonometer measurements in vivo,and fluorescent microscopy,alizarin red staining,paraffin sectioning,scanning and transmission electron microscopy observations in vitro.The corneas of transplanted eyes maintained transparency for as long as 200 d without obvious edema or immune rejection.The corneal thickness of transplanted eyes decreased gradually after transplanting,reaching almost the thickness of normal eyes after 156 d,while the TE-HCE non-transplanted eyes were turbid and showed obvious corneal edema.The polygonal corneal endothelial cells in the transplanted area originated from the TE-HCE transplant.An intact monolayer corneal endothelium had been reconstructed with the morphology,cell density and structure similar to those of normal rabbit corneal endothelium.In conclusion,the transplanted TE-HCE can reconstruct the integrality of corneal endothelium and restore corneal transparency and thickness in PCEP rabbits.The TE-HCE functions normally as an endothelial barrier and pump and promises to be an equivalent of HCE for clinical therapy of human PCEP.