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Background: This study aimed to assess the feasibility of postmortem ultra-high-field magnetic resonance imaging (UHF-MRI) to study fetal musculoskeletal anatomy and explore the contribution of variation in iodine and formaldehyde (paraformaldehyde, PFA) treatment of tissue. Methods: Seven upper extremities from human fetuses with gestational ages of 19 to 24 weeks were included in this experimental study, approved by the Medical Research Ethics Committee. The specimens were treated with various storage (0.2–4% PFA) and staining (Lugol’s solution) protocols and the wrist joint was subsequently imaged with 7.0 T UHF-MRI. Soft-tissue contrast was quantified by determining regions of interest within a chondrified carpal bone (CCB) from the proximal row, the triangular fibrocartilage (TFC), and the pronator quadratus muscle (PQM) and calculating the contrast ratios (CRs) between mean signal intensities of CCB to TFC and CCB to PQM. Results: UHF-MRI showed excellent soft-tissue contrast in different musculoskeletal tissues. Increasing storage time in 4% PFA, CRs decreased, resulting in a shift from relatively hyperintense to hypointense identification of the CCB. Storage in 0.2% PFA barely influenced the CRs over time. Lugol’s solution caused an increase in CRs and might have even contributed to the inversion of the CRs. Conclusions: UHF-MRI is a feasible technique to image musculoskeletal structures in fetal upper extremities and most successful after short storage in 4% PFA or prolonged storage in 0.2% PFA. The use of Lugol’s solution is not detrimental on soft-tissue MRI contrast and therefore enables effectively combining UHF-MRI with contrast-enhanced micro-computed tomography using a single preparation of the specimen. Relevance statement: UHF-MRI can be performed after CE-micro-CT to take advantage of both techniques. Key points: • UHF-MRI is feasible to study human fetal cartilaginous and ligamentous anatomy. • Storage in low PFA concentrations (i.e., 0.2%) improves soft-tissue contrast in UHF-MRI. • Limited preservation time in high concentrations of PFA improves soft-tissue contrast in UHF-MRI. • Prior staining with Lugol’s solution does not reduce soft-tissue contrast in UHF-MRI. Graphical Abstract: [Figure not available: see fulltext.].

Salvaging burned human remains can be a challenging task for the forensic specialists, and interpreting evidence from thermally altered skeletal elements can be difficult. Based on the results presented in this dissertation more is possible than was previously known. In this dissertation, novel ways of finding and analyzing burned human remains are presented to the field of forensic anthropology. This thesis introduces new methods to collect and differentiate cremated bone from construction debris from a fire scene, and estimate the exposure temperature that bones have been exposed to – which is important for forensic investigation. Further, this dissertation provides the reader with new knowledge on heat induced biophysical changes and characteristics that aids the interpretation of skeletal damage that occurred before, during or after the fire. It is important for new methods in forensic practice to comply with legal standards. Accordingly, the value of the presented methods for practice in both the field and the courtroom are thoroughly discussed to inform both the forensic practitioner as well as the legal experts.

Background and Aim Conventional two-dimensional (2D) ultrasound imaging is the primary screening modality used to diagnose congenital heart defects (CHD) before birth. However, the real-life heart is a complex three-dimensional (3D) structure, making prenatal assessment based on conventional ultrasound imaging extremely challenging. Currently, educational resources that directly link conventional prenatal ultrasound imaging to the real-life 3D heart are lacking. Here, we present a pilot study in which we used spatiotemporal image correlation (STIC) technology to create digital 3D fetal heart models. The aim of this pilot study is to determine the feasibility of generating ultrasound-based 3D fetal heart models for the development of web-based learning tool, which could provide this missing link. Methods The hospital database was retrospectively screened for high-quality STIC volumes, obtained as part of routine clinical management of fetuses with a prenatal CHD diagnosis, as well as healthy reference cases. Prenatal findings, pregnancy outcome, postnatal discourse, including postnatal cardiac imaging when available, were retrieved from patient records. Image segmentation and 3D reconstruction of the cardiac ultrasound volumes was performed blinded. Completed models were validated by a senior paediatric cardiologist, who had access to all clinical information. Results A total of 16 models have been generated, including four cases of normal cardiac anatomy, and 12 cases with various CHDs; atrioventricular septal defect (3), transposition of the great arteries (3), venous return anomalies (2), double outlet right ventricle (1), tetralogy of Fallot (1), critical pulmonary stenosis (1), Ebstein’s anomaly (1). In all cases, the morphology of the heart and the arterial and venous connections were successfully reconstructed and validated. Conclusions Our results show that reconstructing the heart and major vessels for the generation of educational 3D fetal heart models is feasible, both in normal cardiac anatomy and various types of CHD. The next step will be expanding our database, and initiating the development of the learning tool that combines the generated 3D models with an interactive ultrasound interface. By developing this tool, we aim at providing the missing link between conventional fetal cardiac ultrasound imaging and the real-life 3D heart.