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Radiocarbon dates from 176 sites along the Delmarva Peninsula record the timing of deposition and sea-level rise, and non-marine wetland deposition. The dates provide confirmation of the boundaries of the Holocene subepochs (e.g. "early-middle-late" of Walker et al.) in the mid-Atlantic of eastern North America. These data record initial sea-level rise in the early Holocene, followed by a high rate of rise at the transition to the middle Holocene at 8.2 ka, and a leveling off and decrease in the late-Holocene. The dates, coupled to local and regional climate (pollen) records and fluvial activity, allow regional subdivision of the Holocene into six depositional and climate phases. Phase A (>10 ka) is the end of periglacial activity and transition of cold/cool climate to a warmer early Holocene. Phase B (10.2–8.2 ka) records rise of sea level in the region, a transition to Pinus -dominated forest, and decreased non-marine deposition on the uplands. Phase C (8.2–5.6 ka) shows rapid rates of sea-level rise, expansion of estuaries, and a decrease in non-marine deposition with cool and dry climate. Phase D (5.6–4.2 ka) is a time of high rates of sea-level rise, expanding estuaries, and dry and cool climate; the Atlantic shoreline transgressed rapidly and there was little to no deposition on the uplands. Phase E (4.2–1.1 ka) is a time of lowering sea-level rise rates, Atlantic shorelines nearing their present position, and marine shoal deposition; widespread non-marine deposition resumed with a wetter and warmer climate. Phase F (1.1 ka-present) incorporates the Medieval Climate Anomaly and European settlement on the Delmarva Peninsula. Chronology of depositional phases and coastal changes related to sea-level rise is useful for archeological studies of human occupation in relation to climate change in eastern North America, and provides an important dataset for future regional and global sea-level reconstructions. [ABSTRACT FROM AUTHOR]

Background: The macrovascular arteriovenous shunt (MAS) connecting the deep inferior epigastric artery (DIEA) and superficial inferior epigastric vein (SIEV) in the abdominal wall has already been identified as an important structure, and further study has been deemed necessary to establish its role and function., Methods: Review of CT angiograms (CTA) of 38 female patients was undertaken, by means of analysis of fine-cut axial images and three-dimensional image reconstructions of the cutaneous vasculature of the deep and superficial vasculature. In vivo dissection of the structure was also performed to establish its communications. Lastly, a histopathological analysis was carried out to investigate its intrinsic structure and function., Results: The MAS was identified in both sides of the abdomen in all subjects and the diameter ranges from 0.72 to 2.81 mm with a median diameter of 1.28 mm. In vivo dissection revealed it as a distinct structure connecting the DIEA and SIEV. Pathological analysis showed that it has characteristics of both elastic and muscular arteries, which constitutes a new vessel., Conclusion: These further investigations have yielded a better understanding of the MAS shunt, its position, structure and function. This can be of crucial importance to reconstructive surgeons when raising the DIEP flap., Competing Interests: Declaration of Competing Interest None declared., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: The authors investigated aesthetic outcome and patient satisfaction in women who have undergone deep inferior epigastric artery perforator (DIEP) flap reconstruction in the setting of postmastectomy radiotherapy. Patients who underwent DIEP flap reconstruction without postmastectomy radiotherapy were the control group., Methods: Participants who had undergone DIEP flap reconstruction between September 1, 2009, and September 1, 2014, were recruited, answered the BREAST-Q, and underwent three-dimensional surface-imaging. A panel assessed the aesthetic outcome by reviewing these images., Results: One hundred sixty-seven women participated. Eighty women (48 percent) underwent immediate DIEP flap reconstruction and no postmastectomy radiotherapy; 28 (17 percent) underwent immediate DIEP flap reconstruction with postmastectomy radiotherapy; 38 (23 percent) underwent simple mastectomy, postmastectomy radiotherapy, and DIEP flap reconstruction; and 21 (13 percent) underwent mastectomy with temporizing implant, postmastectomy radiotherapy, and DIEP flap reconstruction. Median satisfaction scores were significantly different among the groups (p < 0.05). Post hoc comparison demonstrated that women who had an immediate DIEP flap reconstruction were significantly less satisfied if they had postmastectomy radiotherapy. In women requiring radiotherapy, those undergoing delayed reconstruction after a simple mastectomy were most satisfied, but there was no significant difference between the immediate DIEP flap and temporizing implant groups. Median panel scores differed among groups, being significantly higher if the immediate reconstruction was not subjected to radiotherapy. There was no significant difference in panel assessment among the three groups of women who had received radiotherapy., Conclusions: Patients who avoid having their immediate DIEP flap reconstruction irradiated are more satisfied and have better aesthetic outcome than those who undergo postmastectomy radiotherapy. In women requiring radiotherapy and who wish to have an immediate or "delayed-immediate" reconstruction, there were no significant differences in panel or patient satisfaction. Therefore, immediate DIEP flap reconstruction or mastectomy with temporizing implant then DIEP flap surgery are acceptable treatment pathways in the context of post-mastectomy radiotherapy.

Over the last thirty years the internal mammary system has become the recipient of choice when performing free tissue transfer breast reconstruction. The cranial ends of the internal mammary artery and vein are safely and reliably used for anastomosis following division. Using these cranial vessels maintains their normal antegrade direction of flow. As the complexity of reconstruction has increased, use of the caudal end of the internal mammary vein (IMV) has been cited as a convenient option for additional venous drainage. This requires blood flow in a retrograde fashion. The literature to date suggests that this is possible based on the principle that there are no valves in the internal mammary vein. This will be shown to be incorrect. In this study, the internal mammary veins of 32 formalin-preserved cadavers were dissected to specifically look for and to map valves. 21 valves were discovered in the internal mammary veins of 14 of the 32 cadavers (99 internal mammary veins and major branches). 20 of these were bicuspid in nature, one being tricuspid. Valves were found before or after the branching point of the IMVs, and at multiple sites within some individuals. The significance of valve position relative to rib-space and arborisation of parent IMVs is discussed. Whereas existing data support the use of retrograde IMVs to provide a source of additional venous drainage, we would urge caution in using them exclusively. A proportion of IMVs appear to have valves between the commonly used 2nd or 3rd rib-spaces, and the next draining side-branch., (Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)