Ultrathin Descemet stripping automated endothelial keratoplasty versus Descemet membrane endothelial keratoplasty:a fellow-eye comparison

Background:To compare the visual outcome and patients’satisfaction after ultrathin Descemet stripping automated endothelial keratoplasty(UT-DSAEK)and Descemet membrane endothelial keratoplasty(DMEK)performed on fellow eyes of the same patients.Methods:In this retrospective study,the records of 18 pseudophakic patients affected by Fuchs endothelial dystrophy who underwent DMEK in one eye and UT-DSAEK in the fellow eye were reviewed.Best corrected visual acuity(BCVA),corneal pachymetry,keratometry,corneal aberrations,photopic and mesopic contrast sensitivity,and endothelial cell counts measured 12 months after surgery in either eye were analyzed and compared.The results of a satisfaction questionnaire were also reviewed.Results:Twelve months after surgery,BCVA was not significantly different in UT-DSAEK and DMEK eyes(0.10±0.04 and 0.07±0.07 logMAR,respectively);at both 4-and 6 mm optical zones total and posterior corneal higher order aberrations(HOAs),posterior astigmatism and total coma were significantly lower after DMEK;BCVA in both groups was significantly correlated mainly with anterior corneal aberrations;contrast sensitivity was higher after DMEK especially in mesopic conditions and at medium spatial frequencies;the endothelial cell density was similar,although slightly higher in the UT-DSAEK group(p=0.10).The satisfaction questionnaire showed that although patients were highly satisfied from both procedures,more than half of them preferred DMEK and reported a more comfortable and quicker postoperative recovery.Conclusions:DMEK and UT-DSAEK showed no evidence of difference in terms of postoperative BCVA,although DMEK had a better performance in terms of contrast sensitivity,posterior corneal aberrations and overall patient satisfaction.

Incidence of cystoid macular edema after Descemet's stripping automated endothelial keratoplasty

AIM： To determine the incidence of cystoid macular edema（CME） after Descemet＇s stripping automated endothelial keratoplasty（DSAEK）.METHODS： This study included all consecutive patients operated in a Spanish tertiary reference hospital over a period of four years. A total of 55 eyes from 47 patients matched the selection criteria. CME was diagnosed clinically at the slit-lamp and confirmed by optical coherence tomography. RESULTS： Six cases of CME were diagnosed postoperatively, which represented an incidence of 11%. Three patients had previously undergone DSAEK alone（7%; 3/41） and the other three, DSAEK combined with phacoemulsification（21%; 3/14）. Five out of six patients with CME responded to standard therapy.CONCLUSION： CME is a possible complication after DSAEK and can be treated with standard therapy. CME appears more frequently when DSAEK is combined with phacoemulsification and posterior chamber（PC） intraocular lens（IOL） implantation. Intraoperative damage to the corneal endothelial cells might play a role in the pathogenesis of CME. As long as the causes remain unclear, we recommend administering prophylaxis when risk factors are present or when combined surgery is planned.

Effect of the position of the corneal lamella on the frequency of its detachment

AIM:To determine the influence of gaps[places where neither the donor's nor the recipient's Descemet's membrane(DM)is present]and overlaps(places where the recipient's DM is covered by the donor's DM)on the frequency of postoperative detachment of DM endothelial keratoplasty(DMEK)lamellae.METHODS:Totally 64 eyes of 64 patients with Fuchs'endothelial dystrophy or bullous keratopathy indicated for DMEK were randomly divided in two groups.The diameter of the implanted DMEK lamella was the same in both groups(8 mm),but we changed the diameter of the removed recipient DM.In the first group(32 eyes),the circular area was approximately 8.5 mm(gaps);in the second group(32 eyes),the diameter was 7.5 mm(overlaps).Postoperatively we noted all cases of detachment visible on the slit lamp and these cases we indicated for rebubbling.We also measured the uncorrected distance visual acuity(UDVA)as well as corrected distance visual acuity(CDVA)in decimal and postoperative endothelial cell density(ECD).The minimum follow-up time was 6mo.RESULTS:The number of rebubbling procedures in the entire group of patients was 13,i.e.,20.3%,with 6 eyes(18.7%)in the gap group,and 7 eyes(21.9%)in the overlap group.Lamella replacement(re-DMEK)was required in 3(gap group)and 2 patients(overlap group),respectively.The dif ference between the groups was statistically insignificant.The UDVA was 0.54±0.21 in the gap group and 0.58±0.24 in the overlap group.The CDVA was 0.74±0.22 and 0.80±0.16,respectively.ECD was 1920±491 and 2149±570 cells/mm2.The small differences between both groups were not statistically significant.CONCLUSION:We do not notice any difference in the group of patients with overlaps or gaps of DM.The presence of small areas of gaps or overlaps does not affect the frequency of detachment of the DMEK lamellae.