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<p><b>Background</b>Endothelium allotransplantation is the primary treatment for corneal decompensation. The worldwide shortage of donor corneal tissue has led to increasing pressure to seek an alternative for surgical restoration of corneal endothelium. Compressed collagen (CC) gels have excellent biocompatibility, simple preparation course and easy to be manipulated. This study aimed to form a new biomimetic endothelium graft by CC.</p><p><b>Methods</b>We expanded bovine corneal endothelial cells (B-CECs) on laminin-coated CC to form a biomimetic endothelium graft. Scanning electron microscope was used for ultrastructural analysis and tight junction protein ZO-1 expression was tested by immunohistochemistry.</p><p><b>Results</b>The biomimetic endothelium graft, we conducted had normal cell morphology, ultrastructure and higher cell density (3612.2 ± 43.4 cells/mm). ZO-1 localization at B-CECs membrane indicated the bioengineered graft possess the basic endothelium function.</p><p><b>Conclusions</b>A.</p><p><b></b>biomimetic endothelium graft with B-CECs expanded on CC sheet was constructed, which possessed cells' morphology similar to that of in vivo endothelial cells and specific basic function of endothelium layer. This method provided the possibility of using one donor's cornea to form multiple uniformed endothelium grafts so as to overcome the shortage of cadaveric cornea tissue.</p>
ABSTRACT
Background Descemet stripping automated endothelial keratoplasty (DSAEK) is the main treatment for corneal endothelial dysfunction.But the visual outcome after operation varies depending on the difference of corneal diseases.Objective This study was to evaluate and compare the visual outcomes following DSAEK in different keratopathy.Methods The clinical data of 72 eyes of 67 patients with endothelial dysfunction underwent DSAEK from December 2007 to December 2009 at Peking University Third Hospital were retrospectively analyzed.The patients were divided into Fuchs endothelial dystrophy (FED) group (22 eyes of 19 cases),cataract surgeryinduced bullous keratopathy group (37 eyes of 36 eases) and other endothelial keratopathy group (12 eyes of 12 cases).The distribution of visual acuity and LogMAR acuities were compared and evaluation among the 3 groups before operation and 1 day,3,7,30,90 and 180 days after operation.Results Preoperatively,the vision was lower than 0.1 in 71.83％ patients,and all the patients had the visual acuity less than 0.3.No significant difference was found in the preoperative acuity among the FED group,cataract surgery-induced bullous keratopathy group and other endothelial keratopathy group(x2 =3.427,P＞0.05).The visual acuity was ≥ 0.4 in 40 eyes (56.34％) and ≥ 0.1 in 65 eyes (91.55％),and the percentage of vision ≥0.8 was 22.73％ in the FED group,10.81％ in the cataract surgery-induced bullous keratopathy group and 8.33％ in the other endothelial keratopathy group,and no significant difference was found in the percentage of eyes in different visual acuities 180 days after operation (x2 =0.330,P＞ 0.05).In the 3 groups,LogMAR values were gradually decreased with the lapse of the time,showing a significant difference (Ftime =88.000,P ＜ 0.01).In the seventh day after operation,LogMAR value was 1.29 ± 0.57 in the cataract surgery-induced bullous keratopathy group,which was significantly higher than that of the FED group (0.82± 0.43) or other endothelial keratopathy group (0.91 ±0.39) (both at P＜0.05).Ninety days after operation,LogMAR value was 0.40 ±0.28 in the FED group and was significantly declined in comparison with the cataract surgeryinduced bullous keratopathy group (0.64±0.44) and other endothelial keratopathy group (0.73±0.54) (both at P＜0.05).However,no significant differences was seen in the LogMAR values among the three groups 180 days after operation (all at P＞0.05).The vision was stable 3 months after operation in the FED group,however,the vision was still changed over 3 months in the cataract surgery-induced bullous keratopathy group and other endothelial keratopathy group.Conclusions DSAEK is available for corneal endothelial diseases.Visual acuity improves more rapid in FED patients than other keratopathies.
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Background Clinical research showed that the corneal endothelial cell density value from different corneal specula microscopies exist diversity.The relevant literature of SP02,Tomey EM-3000 and SP3000P is still seldom up to now. Objective This research was to assess the repeatability of endothelial cell density measurements by SP02,Tomey EM-3000 and SP3000P respectively and the agreement among 3 kinds of endothelial microscopes.MethodsFifty-four healthy volunteers with the age 17-38 years old were included this research.The written informed consent was obtained from each subject before examination.The corneal endothelial cell densities in the right eyes were analyzed with SP02,Tomey EM-3000 and SP3000P respectively for 3 times under the automatic mode,and the analytical procedure of SP3000P measurement were divided into automatic mode SP3000P (A) and manual correction modes SP3000P( M).The repeatability of each specula microscopy was analyzed by calculating the intraclass correlation coefficients (ICC) and coefficient of variation ( CV ),and the 95％ confidence intervals and plotting Bland-Altman graphs were used to analyze the agreement among these methods.ResultsThe mean corneal endothelial cell densities in the population ＜24 years were significantly higher than the ones ≥ 24 years (t =3.692,P＜0.05 ),but no statistical difference was found between different gender ( t =0.335,P =0.739 ).The mean corneal endothelial cell densities were ( 3058 ± 260 ),( 2954 ± 229 ),( 2668 ± 258 ),( 2734 ± 268 ) cell/mm2 ; the ICCs were 0.957,0.940,0.972 and 0.972 and the CV were 0.063,0.061,0.056,0.058 for SP02,Tomey EM-3000,SP3000P (A) and SP3000P ( M ) respectively.The 95％ confidence intervals were ( - 100.8 - 306.8 ),( 162.6 - 617.4 ),( 109.9-494.1 ) and ( -0.6 - 132.6 ) cell/mm2 for between SP02 and Tomey EM-3000,SP3000P ( A ) and SP02,SP3000P(A) and Tomey EM-3000,SP3000P(A) and SP 3000P(M) respectively.ConclusionsSP02,Tomey EM-3000 and SP3000P(A) have good repeatability in the measurement of corneal endothelial cell density,however the outcome is different.Therefore,it is not interchangeable for the detection of corneal endothelial cell density.The differences of corneal endothelial cell density obtained from these instruments shall be paid high attention for their differences.SP3000P(A) and SP3000P(M) can be used interehangeably and SP3000P(A) is a preferable choice due to its convenience and quickness.
ABSTRACT
Corneal endothelium constitutes a monolayer of polygonal cells. The integrity and health of this layer are essential for the maintenance of normal corneal transparency. This study reported by the first time in a detailed way the ultrastructural morphology and morphometry of the corneal endothelium in normal adult crossbred pigs by using scanning electron microscopy (SEM). A regular pattern of polygonal cells, with predominantly hexagonal cells and clear cell borders, was observed. An oval nucleus that bulges in the centre of the cell, cilia (2-4) in a few peripheral cells, openings of the pinocytotic vesicles, microvilli, borders bars and interdigitated cell borders were observed. The mean endothelial cell area was significantly higher (P<0.05) in the centre than in periphery, with a lower variation coefficient in the former. The mean cell density in periphery was significantly higher (P<0.05) than in centre and 43.9 percent higher than data formerly reported by other authors using specular microscopy, showing the significant shrinkage caused by sample processing for SEM. The mean value of cell sides (pleomorfism) was 5.9, ie. predominant hexagonal shape. The percentage of hexagonal cells was significantly higher in central region (P<0.01), determining a more homogeneous structure. The parameters obtained in this study will be a basement for future investigations about the effect on pig corneal endothelium of drugs, intracamerular surgeries and storage solutions for transplants.
O endotélio corneal é uma monocamada de células poligonais. A integridade e saúde dessa camada são essenciais para a manutenção da transparência corneal normal. Este estudo reportou pela primeira vez, de forma detalhada, a morfologia ultra-estrutural e a morfometria do endotélio corneal de suínos adultos mestiços à microscopia eletrônica de varredura (MEV). A superfície endothelial corneal apresentou um padrão regular de células poligonais, com predomínio da forma hexagonal e de bordas celulares nítidas. O núcleo foi observado como protuberância arredondada no centro da célula. Também foram observados os cílios (2-4) em apenas algumas células da região periférica da córnea, as aberturas das vesículas pinocitóticas na proximidade dos cílios, as microvilosidades, as varas da borda e as bordas celulares em formato de zigzag. A área celular média foi significativamente maior (P<0,05) no centro da córnea do que na periferia, com um coeficiente de variação menor no centro da córnea. A densidade celular média foi significativamente maior na periferia (P<0,05) e 43,9 por cento maior que os dados reportados por outros autores na microscopia especular, o que demonstra o efeito da retração celular durante o processamento das amostras. O valor médio do número de lados das células (pleomorfismo) foi de 5,9, o que evidencia um predomínio do formato hexagonal. A percentagem de células hexagonais foi significativamente maior no centro (P<0,001). Os parâmetros obtidos nesta pesquisa servirão de base para estudos futuros sobre o efeito de medicamentos, cirurgias intracamerulares ou soluções para armazenamento de córneas para transplantes no endotélio corneal do suíno.