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Objective:To explore the long-term influence of donor central graft thickness (CGT) and donor graft size on corneal endothelial cell density (ECD) after Descemet stripping automated endothelial keratoplasty (DSAEK).Methods:An observational case series study was conducted.One hundred and forty-four eyes of 134 patients who underwent DSAEK in Peking University Third Hospital from January 2013 to December 2017 with at least 24-month follow-up were enrolled.Preoperative donor ECD was evaluated by specular microscopy, and ECD was determined by in vivo confocal microscopy at 1, 3, 6, 12, and 24 months postoperatively.Donor CGT was measured by anterior segment optical coherence tomography.According to the 3-month postoperative donor CGT, the subjects were divided into thinner graft group (45 eyes with CGT<100 μm), medium-thick graft group (66 eyes with CGT≥100-<150 μm) and thicker graft group (33 eyes with CGT≥150 μm). According to the donor trephination size, the subjects were divided into smaller graft group (31 eyes with trephination size≥7-<8 mm) and larger graft group (113 eyes with trephination size≥8-<9 mm). The changes of the donor CGT and corneal endothelial cell loss rate were compared at different time points after surgery.The relationships between 24-month postoperative ECD and donor ECD, donor graft size and donor CGT were analyzed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Peking University Third Hospital (No.IRB00006761-2008025). Written informed consent was obtained from each subject prior to any medical examination. Results:The donor CGT was 129.0 (90.8, 160.8), 115.5 (93.0, 146.0), 115.5 (89.0, 151.0), 112.5 (94.3, 146.8) and 114.0 (89.0, 144.5) μm at 1, 3, 6, 12 and 24 months after surgery, showing a statistically significant difference ( H=37.369, P<0.001). There was a statistically significant difference between 1-month and 3-month postoperative CGT ( P<0.001). There was no statistically significant difference in the endothelial cell loss rate among the three different donor CGT groups and between the two different donor graft size groups at any postoperative time points (all at P>0.05). Spearman correlation analysis showed that the 24-month postoperative ECD was strongly positively correlated with the preoperative donor ECD( rs=0.783, P<0.001), which was not associated with donor graft size and donor CGT ( rs=0.141, P=0.093; rs=-0.044, P=0.600). Conclusions:Larger postoperative ECD is correlated with larger preoperative ECD of donor graft.Lower long-term corneal endothelial cell loss rate after DSAEK is associated with thinner and larger diameter of donor graft.
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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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<p><b>BACKGROUND</b>Though there have been various methods for harvesting and preserving descemet membrane (DM) and intact endothelium, there is no literature about the morphological evaluation of endothelium after graft preparation for descemet membrane endothelial keratoplasty (DMEK). The aim of this study was to establish and improve a simple method for preparing, preserving, and morphologically evaluating the donor graft for DMEK.</p><p><b>METHODS</b>To obtain a donor graft, an air bubble was formed by injecting a 29 G needle with 1 ml sterile air into a small edge created outside the Schwalbe line. Another needle was inserted into the bubble through the stroma to aspirate the air or replace half the air with organ culture medium. Trypan blue was used to mark the location for small incision to improve the success rate. Frozen sections were stained with hematoxylin and eosin (HE). Based on the air bubble, DM grafts were divided into four groups: group A (normal control), graft without any operative technique; group B, graft with zero-pressure air bubble; group C, graft with full-pressure air bubble; group D, graft with half-pressure air bubble. The four groups of grafts were preserved for 24 hours to observe the effect of bubbles on cells. The gross and ultrastructure morphologies were evaluated using alizarin red and scanning electron microscopy (SEM), respectively.</p><p><b>RESULTS</b>Donor grafts were harvested via the air bubble technique, facilitated by prior trypan blue staining. HE-stained sections revealed a pure graft without stroma. There were no significant changes under light microscope. In group A, SEM revealed a confluent layer of polygonal endothelium with distributed microvilli exhibiting characteristics of interdigitating junctions. In group B, intercellular borders became thinner. In group C, interdigitations were almost flat and microvilli were observed less frequently. In group D, other than less microvilli, there were minimal changes.</p><p><b>CONCLUSIONS</b>The donor graft preparation method appears to be effective and convenient. Properly decreasing the air pressure could protect and preserve the endothelium.</p>