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Background Precise optic disc size measurements based on anatomically exact disc margins are fundamental for a correct assessment of glaucoma suspects. Computerized imaging techniques, such as confocal-scanning-laser-tomography (CSLT), which applies operator defined boundaries and optical-coherence-tomography (OCT), which incorporates an alternative detectable landmark (Bruch’s-membrane-opening (BMO)), have simplified the planimetry of the optic disc and BMO-area, respectively. This study’s objectives are to compare both modalities for area and to define a threshold for macro-BMO using BMO-OCT. Methods Retrospectively, patients that simultaneously received CSLT and BMO-OCT scans were included. Their images were correlated and agreement was determined using Bland-Altman-analysis. The diagnostic power of a macro-BMO threshold using OCT was derived after creating a receiver-operating-characteristics-curve using the well-established analogous CSLT threshold (2.43 mm2). Results Our study included 373 eyes with a median optic disc area by CSLT/ BMO-area by OCT of 2.56 mm2 and 2.19 mm2 respectively. The Bland-Altman-analysis revealed a systematic deviation with a diverging tendency with increasing area, which enabled the creation of the following mathematical relation: disc-area (CSLT)*0.73 + 0.3 = BMO-area (OCT). BMO-area of 2.19 mm2 showed the best diagnostic power for identifying macro-BMOs using OCT (sensitivity: 75%, specificity: 86%). Conclusions Area measurements (CSLT optic disc area vs. BMO-area by OCT) showed a systematic deviation with a divergent tendency with increasing size. Our mathematical equation offers an estimated comparison of these anatomically diverse entities. Considering BMO-OCT´ anatomical accuracy, the 2.19 mm2 threshold may improve discernment between glaucoma suspects and norm variants.

Background The demographic change in Germany will lead to an increase in irreversible age-related eye diseases. This will increase the need for specialised care facilities for visually impaired people. Due to reduced mobility, residents in such facilities often do not receive adequate ophthalmological care. New concepts must therefore be considered for this group of patients. One approach is to set up an ophthalmological examination unit within the facility combined with regular visits by an ophthalmologist. We now present the experience with such a model in a home for the blind. Patients and Methods The project was initiated in 2009. Since then there have been visits by medical staff of the Eye Center at Medical Center, University of Freiburg, every two weeks. All patient records (2010 – 2017) were reviewed systematically. The following data were extracted in a structured and anonymous way: Age at first presentation, gender, ophthalmological diagnoses and if a therapy was initiated. This data set was finally analysed descriptively. Results Out of 130 residents aged between 48 and 100 years, half were between 78 and 90 years old. The youngest resident was 48, the oldest 100 years old. The median visual acuity was 0.2. Sixty percent of the residents had at least mild visual impairment according to the WHO (visual acuity < 0.5; category 1 – 6). In one of 6 – 7 residents, visual acuity could not be determined using Snellen charts. The most frequent ophthalmological diagnoses included cataract (44%), age-related macular degeneration (36%) and glaucoma (29%). In 67 residents (52%), the ophthalmological examination lead to treatment, such as application of local therapy or planning an operation. Conclusion In every second resident, the ophthalmologistʼs visit lead to treatment during the observation period. This underlines the difficulty of providing ophthalmological care even in specialised institutions for the blind and visually impaired, which is possibly due to the residentsʼ mobility problems. The concept presented here has established a low-threshold, sustainable and high-quality ophthalmological service on site. These positive experiences indicate that corresponding measures may also be useful for other locations. However, in order to implement such a project on a larger scale, suitable financing and accounting modalities for the construction measures, the nursing staff and the ophthalmological procedure still need to be developed.