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PURPOSE: To evaluate the efficiency of using anterior segment optical coherence tomography (AS-OCT) as a non-invasive and sterile screening method in the eye bank to detect corneal grafts with curvature and/or thickness anomalies, thus improving the graft selection for corneal transplantation. METHODS: 1222 donor corneal tissues mounted in sterile organ culture flasks were imaged using an AS-OCT (CASIA 2 - Tomey, Nagoya, Japan) between January 2018 and September 2022. The corneal tissues were preserved at least 12 hours in organ culture medium 2 (containing 6% dextran T-500) before the measurement in order to allow deswelling prior to the examination. Depth scans were performed sterilely through the organ culture flask from the posterior surface of the corneal tissues within a 7 mm central zone to create 3D volume data. The volume data set was imported to MATLAB (MathWorks Inc., Natick, Massachusetts, USA) and, after preprocessing the data and defining the region of interest (ROI), the edge of the front and back surfaces of the corneal tissues was detected. Subsequently, the adaptation of a sphero-cylindrical surface model was carried out with raytracing. The radii of curvature for the front and back surfaces and the central corneal thickness were determined according to the method proposed by Mäurer, Eppig, Langenbucher et al at the Institute of Experimental Ophthalmology, Homburg/Saar, Germany. RESULTS: The mean steep/flat front surface radius was 7.46 ± 0.29 (6.07 - 9.29)/7.69 ± 0.24 (6.70 - 9.50) mm, the corresponding values for the back surface being 6.48 ± 0.32 (5.30 - 8.00)/6.80 ± 0.31 (5.81 - 8.00) mm and the mean central thickness was 611.5 ± 85.6 (378.5 - 1457.2) µm. Anomalies (beyond ± 2 or ± 3 standard deviations SD) were found in 111 or 41 corneas (9.1% or 3.4%) for anterior surface curvature, 135 or 38 for corneas (11.0% or 3.1%) for the posterior surface, and 53 or 15 corneas (4.3% or 1.2%) for central corneal thickness. CONCLUSION: The AS-OCT provides an objective, sterile and semi-automated screening method to identify corneal morphological and refractive alterations (e.g. keratoconus, status post keratorefractive surgery) to further optimize corneal donor selection in the eye bank. Corneal donors with curvature or thickness anomalies +/- 3 SD (eminence-based) do not have to be discarded but can be used for posterior lamellar keratoplasty, especially DMEK in Germany.

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BACKGROUND: Broad spectrum antibiotics are often used for the prophylaxis of infectious endocarditis and treatment of odontogenic infections, but there are limited data related to antibiotic use and adherence to prescription guidelines.  METHODS: Data from patients with tooth extraction between 2014 and 2018 were selected from a database of a regional health insurance fund. We created three data sets, one based on all tooth extractions, one on multiple teeth extractions, and one including only single tooth extraction. After data collection, descriptive analysis was carried out. The differences in prescription pattern of antibiotic medicine were tested by χ2 test, Student´s t-test or ANOVA. RESULTS: From 43,863 patients with tooth extraction, 53% were female, and 3,983 patients (9.1%) filled a prescription for antibiotic medicine. From 43,863 patients, 157 patients (0.4%) had endocarditis risk, but only 8 patients of these (5.1%) filled an antibiotic prescription. In total, 9,234 patients had multiple and 34,437 patients had only one tooth extraction. Patients with more than one tooth extraction received more often antibiotic treatment (10.7%) compared to those with single tooth extractions (χ2 = 36; p < 0,001). Patients with more than one tooth extraction were older, however, younger patients received antibiotics more frequently (t = 28,774, p = 0.001). There was no relationship with endocarditis risk status. Clindamycin and amoxicillin/clavulanic acid were the most frequently prescribed antibiotic medicines. CONCLUSIONS: In this retrospective cohort study, dentists did not discriminate prophylactic antibiotic prescription with regard to endocarditis risk status. A factor influencing prescribing behaviour of antibiotic medicines was the number of extracted teeth.

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PURPOSE: To evaluate the reliability and efficiency of sterile corneal thickness measurements of donor corneas stored in a plastic culture flask filled with organ culture medium I (MI) or II (MII) based on tomographic data using two different software: the built-in software of the anterior segment OCT (AS-OCT) and a MATLAB self-programmed software. METHODS: Twenty-five (25) donor corneas (50%) stored in MI and 25 (50%) in MII were imaged 5 times consecutively using an AS-OCT. The central corneal thickness (CCT) was measured both with the manual measurement tool of the AS-OCT (=CCTm) and with a MATLAB self-programmed software allowing (semi-)automated analysis (=CCTa). We analyzed the reliability of CCTm and CCTa using Cronbach´s alpha (α) and Wilcoxon signed-rank test. RESULTS: Concerning CCTm, 68 measurements (54.4%) in MI and 46 (36.8%) in MII presented distortions in the imaged 3D-volumes and were discarded. Concerning CCTa, 5 (4%) in MI and 1 (0.8%) in MII were not analyzable. The mean (± SD) CCTm was 1129 ± 6.8 in MI and 820 ± 5.1 µm in MII. The mean CCTa was 1149 ± 2.7 and 811 ± 2.4 µm, respectively. Both methods showed a high reliability with a Cronbach´s α for CCTm of 1.0 (MI/MII) and for CCTa of 0.99 (MI) and 1.0 (MII). Nevertheless, the mean SD of the 5 measurements was significantly higher for CCTm compared to CCTa in MI (p = 0.03), but not in MII (p = 0.92). CONCLUSIONS: Sterile donor tomography proves to be highly reliable for assessment of CCT with both methods. However, due to frequent distortions regarding the manual method, the (semi-)automated method seems to be more efficient and should be preferred.

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To evaluate the reliability and efficiency of sterile pachymetric measurements of donor corneas based on tomographic data using two different methods: a "manual" and a "(semi-)automated" method. Twenty-five (25) donor corneas (50%) stored in MI and 25 (50%) in MII were imaged 5 times consecutively using an anterior segment OCT (AS-OCT). The central corneal thickness (CCT) was measured both with the manual measurement tool of the AS-OCT (= CCTm) and with a MATLAB self-programmed software allowing (semi-)automated analysis (= CCTa). We analyzed the reliability of CCTm and CCTa using Cronbach´s alpha (α) and Wilcoxon signed-Rank Test. Concerning CCTm, 68 measurements (54.4%) in MI and 46 (36.8%) in MII presented distortions in the imaged 3D-volumes and were discarded. Concerning CCTa, 5 (4%) in MI and 1 (0.8%) in MII were not analyzable. The mean (± SD) CCTm was 1129 ± 6.8 in MI and 820 ± 5.1 µm in MII. The mean CCTa was 1149 ± 2.7 and 811 ± 2.4 µm, respectively. Both methods showed a high reliability with a Cronbach´s α for CCTm of 1.0 (MI/MII) and for CCTa of 0.99 (MI) and 1.0 (MII). Nevertheless, the mean SD of the 5 measurements was significantly higher for CCTm compared to CCTa in MI (p = 0.03), but not in MII (p = 0.92). Sterile donor tomography proves to be highly reliable for assessment of CCT with both methods. However, due to frequent distortions regarding the manual method, the (semi-)automated method is more efficient and should be preferred.

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BACKGROUND AND OBJECTIVE: Sterile donor tomography enables the detection of corneal tissues with refractive anomalies. The aim of this study was to determine the curvature and thickness of donor corneas to support proper selection in the eye bank. METHODS: 704 donor corneas (Klaus Faber Center, LIONS Eye Bank Saar-Lor-Lux, Trier/Westpfalz, in Homburg/Saar) were measured using the anterior segment optical coherence tomograph (AS-OCT) CASIA 2 (Tomey Corp., Nagoya, Japan). The corneoscleral discs were measured in their cell culture flask, which was positioned in a holder on the chin rest of the AS-OCT, after conversion to medium II (with 6% dextran T-500). The measured raw data were analysed and processed in MATLAB (MathWorks Inc., Natick, Massachusetts, USA), after which the refractive power of the steep and flat meridian at the anterior and posterior surface and the central corneal thickness (CCT) of the donor corneas were determined. Results values are expressed as mean x̅ ± standard deviation SD. RESULTS: The mean refractive power of the steep/flat meridian at the anterior surface was 45.4 ± 1.8 D/44.0 ± 1.3 D, the corresponding values for the posterior surface were - 6.2 ± 0.3 D/- 5.9 ± 0.2 D, and the mean CCT was 616.3 ± 85.1 µm. Of the 704 (100%) measured donor tissues, 590 (83.8%)/670 (95.2%) donor corneas showed no anomaly beyond respectively x̅ ± 2 SD/x̅ ± 3 SD among the 5 examined parameters. 72 (10.3%)/23 (3.3%) donor corneas had only 1 anomaly, 26 (3.7%)/10 (1.4%) had 2 anomalies, 10 (1.4%)/1 (0.1%), 3 anomalies, 5 (0.7%)/0 (0.0%), 4 anomalies, and 1 (0.1%)/0 (0.0%), 5 anomalies. CONCLUSIONS: AS-OCT provides an objective and sterile screening method to identify corneal tissues with curvature anomalies in order to further optimise donor selection in the eye bank. To avoid postoperative refractive surprises, donor corneas with a total refractive power that deviates > ± 3 SD from the mean should not be used for penetrating or anterior lamellar keratoplasty, but may be suitable for posterior lamellar keratoplasty (DMEK or DSAEK). In the future, sterile donor tomography could enable: (1) the harmonisation of donor and recipient tomography, which may minimise residual astigmatism for a particular donor-recipient pair; and (2) the improvement of IOL power calculation in a classical triple procedure by means of regression analysis between pre- and postoperative total refractive power of corneal grafts.

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The applicability of donor and recipient tissue matching in corneal transplantation ("harmonization") to reduce residual astigmatism after keratoplasty was simulated using Matlab software. The height profile of the donor and recipient corneas was measured using the anterior segment optical coherence tomography (AS-OCT) Casia 2. After best fit of the donor button in the recipient bed the mean height difference as the mismatch, which had to be minimized, was derived from the height profile of the donor and recipient corneal front and back surfaces. The donor button was rotated in the recipient bed to extract the best fit situation where the mean height difference was minimized. After successful simulation, the procedure will be transferred to real measurement data.

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PURPOSE: To determine the changes of corneal thickness and curvature of human corneal grafts in organ culture medium II, containing dextran T500 6%, before keratoplasty. METHODS: We examined the tomography of 24 corneas from our eye bank transferred from medium I into medium II. Images were repeated hourly during 24 hours using an anterior segment optical coherence tomography. The central corneal thickness (CCT) was measured with the manual measurement tool of the anterior segment optical coherence tomography. The radii of curvature (anterior flat and steep and posterior flat and steep) were measured with a MATLAB self-programmed software for "sterile donor tomography." RESULTS: The mean CCT (±SD) at baseline (T0) was 727 ± 156 µm. It reached 581 ± 103, 506 ± 84, 472 ± 79, and 456±7 µm after 6, 12, 18, and 24 hours, respectively. After 12 hours, 83% of the final deswelling was achieved. The radii of curvature (±SD) at baseline (T0) were (posterior flat, posterior steep, anterior flat, and anterior steep) 6.6 ± 0.5, 6.2 ± 0.5, 7.7 ± 0.4, and 7.4 ± 0.4 mm, respectively. After 24 hours, the radii of curvature reached 6.8 ± 0.1, 6.6 ± 0.3, 7.6 ± 0.1, and 7.4 ± 0.2 mm, respectively. CONCLUSIONS: The kinetics of the deswelling process in medium II follow a hyperbolic curve. Considering a CCT of 506 µm at T12, we assume that a time interval of 12 hours in medium II might be enough for clinical purposes. This result might help to keep storage in medium II as short as possible to escape potential toxic effects of dextran in medium II. The radius of curvature does not seem to change within 24 hours for all measured surfaces.

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PURPOSE: We present a concept for non-contact tomographic measurement and characterization of corneal donor tissue within the cell culture medium. The purpose is to screen corneal tissue for pathologies or alterations after refractive surgery. METHODS: Image acquisition is performed with the clinical anterior segment optical coherence tomography (OCT) Casia 2 (Tomey Corp., Nagoya, Japan). An edge detection of the anterior and posterior surfaces of the donor cornea is performed after preprocessing and noise reduction of the data. A sphero-cylindrical surface model is then fitted to the detected surfaces in order to determine the radius of curvature, the surface refractive values, the keratometer readings and central thickness of the cornea. A cornea phantom with defined geometry was used to validate the algorithm and finally 74 donor corneas were measured in the cell culture flask. RESULTS: The large axial measurement range of the OCT enables measurement of the phantom and tissue samples within the culture flask with a diameter of approximately 7 mm. The developed program reliably removes artifacts caused by the wall of the flask and those originating from the tissue holder and facilitates calculation of the sphero-cylindrical model for the anterior and posterior surfaces. The measurement results for the phantom show minimal deviations from the manufacturer's data. The measured radius of curvature of the corneas was within normal limits. CONCLUSION: The anterior OCT Casia 2 enables rapid 3­dimensional measurement of corneal donor tissue in the culture medium. The measurable range covers approximately 7 mm of the graft diameter, which is mainly limited by the holder used for the donor tissue. Topographical and pachymetric parameters could be derived from the volume data.

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PURPOSE: To compare corneal tomography and its statistical uncertainty for measurements obtained by three clinically used corneal tomographers: A Scheimpflug camera (Pentacam HR), a swept source optical coherence tomography system (CASIA SS-1000), and Placido ring imaging (TMS-5). MATERIAL AND METHODS: Repeated measurements with all three devices on 34 normal eyes were used to estimate the repeatability, precision, and mean values of corneal elevation and pachymetry within 8 mm diameter. The repeatability (standard deviation) was calculated for each data point of the corneal elevation data-maps of anterior and posterior cornea as well as for the pachymetry data-maps. Uncertainty on the position of the eye at each measurement might contribute to the differences between elevation data-maps. To take this into account, we defined the precision as the standard deviation for the elevation data-maps of anterior and posterior cornea after correction of misalignment-effects (rotation, translation). The mean elevation and pachymetry data-maps were fitted with Zernike polynomials for interdevice-comparison. RESULTS: Pentacam HR offered the best repeatability and precision for the anterior corneal elevation (<3 and <1.6 µm, respectively). CASIA SS-1000 offered good repeatability and precision with high resolution for posterior corneal elevation, and the best repeatability for pachymetry (<3 µm). TMS-5 measured anterior elevation with similar repeatability to CASIA SS-1000 (<6 µm). The data-maps of the three tomographers could not be used interchangeably. The largest differences were observed for pachymetry and posterior corneal elevation data-maps. CONCLUSIONS: Misalignment limited the repeatability of TMS-5 and Pentacam HR, but had little influence on the repeatability of CASIA SS-1000.

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Illness appraisals provide important context to help understand the way individuals cope with chronic illness. In the present study, a qualitative approach to the analysis of HIV diagnosis experience narratives in a sample of 100 people newly diagnosed with HIV revealed five groups that differed in their initial illness appraisals: HIV as Chronic Illness, Concern about Dying, Stigmatization, Threat to Identity, and Other Threats Overshadow HIV. When compared on quantitatively measured depressive mood, the groups differed on level and trajectory over the course of the first year post-diagnosis. Although the experience of living with HIV has changed significantly with the advent of effective Antiretroviral Therapies (ART), there were a number of similarities between the appraisals of this group of participants who were diagnosed post ART and groups who were diagnosed before ART became widely available. Posttest counselors and other HIV service providers should take individual differences in illness appraisals into account in order to help newly HIV-positive clients manage their healthcare and cope adaptively with their diagnosis.

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In this article we present background, theoretical rationale, and pilot data on the development of an intervention designed to increase positive affect in people living with serious health-related stress. This proof-of-concept study demonstrated that a multiple-component positive affect intervention is feasible and acceptable for people newly diagnosed with HIV. Retention in the intervention and adherence to home practice were high. Participants reported significant increases in positive affect and significant decreases in negative affect. This positive affect intervention can serve as a template for programs to be developed to help people experiencing health-related and other types of life stress.

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New CDC guidelines for HIV testing as well as the introduction of rapid tests may increase the number of HIV tests conducted in the USA and make testing a more routine part of medical care. However, little is currently known about the experience of those receiving positive results. In this study, face-to-face interviews were conducted with 50 participants who had recently learned they were HIV positive in the San Francisco Bay Area. Ninety-two percent were male, 36% were persons of color. Participants were asked to tell their story of testing positive for HIV. Interviews were transcribed for team-based narrative qualitative analysis. The majority of participants were tested at either a hospital or an HIV test site. While some suspected they might have HIV, most were tested while seeking care for another health concern or for routine testing. Fifty-eight percent had a rapid test. Test results were typically given by medical staff or HIV test counselors. The manner in which the news was delivered affected an individual's testing experience. For seven (14%) of the participants, the provider giving the results was so upset or agitated that it added to the participant's distress over the diagnosis. Responses to the news varied greatly from being too shocked to comprehend what they were being told to immediately accepting the news and feeling ready for action. The patient/provider interaction plays a pivotal role in both follow-up care and prevention decisions. Therefore, HIV service providers need to be cognizant of the way in which their role in the testing process, including delivery of the news and post-test counseling impacts the individual's experience of testing positive.

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OBJECTIVES: To develop and test the feasibility and acceptability of a structured design for a massage therapy clinical trial that included a treatment arm designed to control for the non-specific effects of a massage therapy intervention. DESIGN: Pilot randomized controlled clinical trial. SETTING: University-integrated medicine research clinic. INTERVENTIONS: Participants were randomized to a structured Swedish-style massage therapy intervention, a light-touch bodywork control intervention, or usual medical care. Details of the interventions are provided. MAIN OUTCOME MEASURES: The primary outcome measures were the adherence of the participants to the study protocol and the perception of the intervention experience. RESULTS: Forty-four participants were randomized. Participants often found adherence to the twice-weekly outpatient bodywork interventions to be somewhat difficult; while, overall, 84% of participants completed the study, only 76% of those in an intervention arm successfully completed the trial. Participants randomized to the massage arm expressed uniformly positive attitudes both before and after the intervention. While some participants randomized to the light-touch bodywork arm initially expressed some reservations about their randomization assignment, all participants available for interview were pleased with their experience after the intervention period. CONCLUSIONS: The proposed design was found to be relatively straightforward to implement and acceptable to participants. Early disappointment with not receiving massage therapy expressed by the light-touch intervention participants dissipated quickly. Twice-weekly outpatient intervention appointments were found to be highly burdensome for many patients actively undergoing chemotherapy, thus reducing adherence.

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