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Abstract. Vision loss due to corneal injuries or diseases can be treated by transplantation of human corneal grafts (keratoplasty). However, quality assurance in retrieving and cultivating the tissue transplants is confined to visual and microbiological testing. To identify previous refractive surgery or morphological alterations, an automatic, noncontact, sterile screening procedure is required. Twenty-three corneal grafts have been measured in organ culture with a clinical spectral-domain optical coherence tomographer. Employing a biconic surface fit with 10 degrees of freedom, the radii of curvature and conic constants could be estimated for the anterior and posterior corneal surfaces. Thereupon, central corneal thickness, refractive values, and astigmatism have been calculated. Clinical investigations are required to elaborate specific donor-host matching in the future.

The EEG estimation of listening effort has been proven to efficiently map subjectively perceived effort on an objective scale. However, it has mostly been performed in controlled audiometric laboratory environments. In this study, we investigated the feasibility of the EEG listening effort assessment in a multisensory demanding environment. For this purpose, two mobile EEG acquisition systems were used to extract the objective listening effort of the ongoing oscillatory activity (OLEosc) while driving. As an auditory paradigm was presented to trigger listening effort, the simulated driving scenario served as a competing task responding to different modalities. The OLEosc was compared with a subjective rating of the expended listening effort and the task performance. Furthermore, we considered time resolved listening effort profiles over the duration of the paradigm. The results showed that the practical assessment of listening effort in a multimodal real life setting is viable. The OLEosc could be extracted and followed the subjective listening effort. Moreover, the analysis of the dynamic listening effort profiles unveiled further information such as "surrender effects", when the subjects ceased to solve the auditory task due to the intense multimodal load.