Retroperitoneum revisited: a review of radiological literature and updated concept of retroperitoneal fascial anatomy with imaging features and correlating anatomy.

PURPOSE: Spread of disease in the retroperitoneum is dictated by the complex anatomy of retroperitoneal fasciae and is still incompletely understood. Conflicting reports have led to insufficient and incorrect anatomical concepts in radiological literature. METHODS: This review will discuss previous concepts prevalent in radiological literature and their shortcomings will be highlighted. New insights from recent anatomical and embryological research, together with imaging examples, will be used to clarify patterns of disease spread in the retroperitoneum that remain unexplained by these concepts. RESULTS: The fusion fascia and the renal fascia in particular give rise to planes and spaces that act as vectors for spread of disease in the retroperitoneum. Some of these planes and structures, such as the caudal extension of the renal fascia, have previously not been described in radiological literature. CONCLUSION: New insights, including the various fasciae, potential spaces and planes, are incorporated into an updated combined retroperitoneal fascial concept.

Fluorescence-guided minimally-invasive resection of abdominal paragangliomas using indocyanine green.

This retrospective study explores the utility of near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) in enhancing the intraoperative identification and guidance for the resection of abdominal paragangliomas. They can be challenging to detect during minimally invasive surgery, due to their anatomical location, varying size and similar appearance in regard to their surrounding tissue. Patients with suspected abdominal paragangliomas planned for a minimally-invasive resection were included. As part of standard of care they received single intravenous dose of 5 mg ICG after abdominal exploration. NIR fluorescence imaging of the anatomical region of the suspected lesion was performed immediately following intravenous administration, to assess fluorescence signals, intraoperative identification, and histopathological correlation. Out of five resected suspicious lesions, four were imaged with NIR fluorescence, pathology confirming four as paragangliomas, the latter turned out to be an adrenal adenoma. NIR fluorescence identified all four lesions, surpassing the limitations of white-light visualization. Homogeneous fluorescence signals appeared 30-60 s post-ICG administration, which lasted up to 30 min. The study demonstrates the feasibility and potential clinical value of fluorescence-guided minimally-invasive resections of abdominal paragangliomas using a single intravenous ICG dose. These findings support the scientific basis for routine use of ICG-fluorescence-guided surgery in challenging anatomical cases, providing valuable assistance in lesion detection and resection.

Evaluation of saline, RPMI and DMEM/F12 for storage of split-thickness skin grafts.

Skin grafting is standard of care for severe burn and trauma patients. Graft sites are often accompanied with more pain than the burn sites. To minimize graft site areas, excess skin remaining after harvesting, is stored in saline at 4°C to be used for transplantation up to 1 week later. However, the optimal storage solution and maximum storage time are not known. We set out to determine the storage time after which stored skin is still viable. In addition, different storage solutions were tested. Split-thickness skin from 15 donors with a thickness of 0.3 mm was stored in normal saline, in medium, RPMI or DMEM/F12, allowing pairwise comparison. Biopsies were taken up to 3 weeks for histology and for skin viability assessment using an MTT based activity assay. Activity of the saline stored control decreased to 62% at day 7 and to 27% at day 14. Activity was retained at a higher level in RPMI and was 78% at day 7 and 70% at day 14. Results with DMEM/F12 showed a similar trend as the saline control. Based on activity, RPMI was found to be superior to DMEM/F12 (on days 3 and 10) and both saline and DMEM/F12 (on days 14 and 21). Capability to proliferate (BrdU incorporation) did not differ between media, up to 7 days. Histologically, the number of apoptotic cells increased in time but differences between media were not noted. Based on these results, RPMI would be an improvement over saline in retaining viability of skin grafts during storage, and possibly in improved take rate.