BackgroundThe goal of this study was to investigate numbers, indications, surgical techniques, and experiences of amniotic membrane transplantation at the University Eye Hospital Tübingen over the last 16 years.Material/MethodsData from all amniotic membrane transplantations from January 2001 to December 2016 were retrospectively analyzed. Data was accessed from the electronic database and the annual reports of the Eye Bank at the University Eye Hospital Tübingen.ResultsA total of 771 amniotic membrane transplantations were performed between 2001 and 2016 at the University Eye Hospital Tübingen. The mean number of amniotic membrane transplantations was 48 per year (range: 7–81). Overall, the mean number of amniotic membrane transplantations more than doubled, from 31 amniotic membrane transplantations per year during the first 8-year period to 66 amniotic membrane transplantations per year during the second 8-year period (p<0.0001). The most common surgical indications for amniotic membrane transplantation were corneal ulcers and persistent corneal epithelial defects. The inlay, overlay, and sandwich technique became the favored surgical methods for various disorders of the ocular surface.ConclusionsOur study showed a significant increase of amniotic membrane transplantations from 2001 to 2016. This increase is likely influenced by the introduction of different surgical amniotic membrane transplantation techniques, the rising knowledge about containing growth factors, neurotrophins and cytokines, and the demographic change with aging of the population.

BackgroundThe aim of this study was to investigate the evolution of surgical methods in and leading indications for corneal transplantation from 2005 to 2016.Material/MethodsData from the corneal graft waiting list and from all keratoplasties carried out between 2005 and 2016 at the University Eye Hospital Tübingen were retrospectively evaluated.ResultsA total of 1259 keratoplasties were performed between 2005 and 2016 at the University Eye Hospital Tübingen. The most common surgical indications for corneal transplantation were Fuchs endothelial corneal dystrophy (45.5%) and keratoconus (14.2%). The mean rate of corneal transplantations almost doubled from 71 keratoplasties per year in the first 6-year period to 139 keratoplasties per year in the second 6-year period (P=0.005). The number of penetrating keratoplasties remained similar. The number of Descemet membrane endothelial keratoplasties (DMEK) increased significantly from 2008 to 2016 (P<0.0001). One DMEK procedure was performed in 2008 (representing 1.4% of all transplantations), while 75 DMEK procedures were performed in 2016 (representing 60.5% of all transplantations) (P<0.0001). DMEK became the favored surgical method for endothelial disorders, exceeding penetrating keratoplasty in 2013.ConclusionsOur study shows evolutionary changes in preferred corneal transplantation techniques and leading indications for keratoplasty from 2005 to 2016. Since its introduction a decade ago, DMEK is currently the golden standard in the management of corneal endothelial dysfunction.

This study assessed the influence of donor, environmental, and logistical factors on the contamination rates of the conjunctival swabs and organ culture media of human donor eyes.In total, 1008 conjunctival swabs and 418 organ culture media samples from 504 consecutive human donor eyes were analyzed. Cross-tabulation, chi-squared tests, and Fisher's exact tests were used to assess the influence of the different factors on the contamination rates of the conjunctival swabs and organ culture media.The overall contamination rates were 28.4% for the conjunctival swabs and 1.0% for the organ culture media. A prolonged time between death and the conjunctival swab collection was associated with an increased conjunctival swab contamination rate [odds ratio (OR) = 1.9, 95% confidence interval (CI) = 1.2–3.0, P = .007]. The highest conjunctival swab contamination rate was found in the corneas procured in external institutions (outside the university hospital) (44.1%, OR = 3.6, 95%CI = 1.5–8.4, P = .003). Hospitalization times of 2 to 7 days prior to death were associated with an increased conjunctival swab contamination risk (OR = 2.6, 95%CI = 1.1–5.8, P = .021). However, the sex, age, cause of donor death, differentiation between septic and aseptic donors, differentiation between heart-beating brain-dead multiorgan donors and cadaveric donors, a warmer mean monthly temperature, and death to corneoscleral disc excision time did not significantly increase the conjunctival swab contamination risk. In addition, none of these factors affected the organ culture media contamination risk. Moreover, a positive conjunctival swab did not significantly increase the media contamination risk (P = .08). Surprisingly, the microorganisms causing media contamination were present at 50% of the amount detected on the conjunctival surface of the respective donor eye.A prolonged time between death and the conjunctival swab collection, a hospitalization time of 2 to 7 days prior to death, and corneal collection outside the university hospital seemed to be the main factors responsible for an increased conjunctival swab contamination risk. In addition, our investigation illustrated that a positive conjunctival swab is not a strong indicator for organ culture media contamination. Critical discussion is necessary regarding the validity of conjunctival swabs as prognostic parameters for organ culture media contamination.

Background This study investigated the effect of donor-dependent factors on contamination rates of conjunctival swabs of human donor eyes. Material/Methods From July 2015 to September 2017 a total of 1008 conjunctival swabs from 504 consecutive human donor eyes were analyzed. Cross-tabulation, chi-squared tests, and Fisher’s exact tests were used to evaluate the effect of donor-dependent factors on contamination rates of conjunctival swabs. Results The mean conjunctival swabs contamination rate was 28.4%. Donors with the diagnosis of carcinoma or metastases were associated with an increased conjunctival swab contamination rate [odds ratio (OR)=1.8, 95% confidence interval (CI)=1.2–2.6, p=0.007; OR=1.7, 95% CI=1.1–2.6, p=0.016; respectively]. However, the age, sex, diagnosis of diabetes mellitus, and donors who received chemotherapy did not significantly increase the conjunctival swab contamination risk. Conclusions Donors with the diagnosis of a carcinoma or metastases seemed to be predisposed to increased conjunctival swab contamination risk.