Citations

PurposeFree flap reconstruction in head and neck cancer patients with prior tumor resection, neck dissection, and irradiation is clinically challenging. The purpose of this study was to investigate the reliability and outcome of using the anterolateral thigh (ALT) flap and transverse cervical recipient vessels for microvascular reconstruction in patients with depleted vessels in the head and neck region caused by previous surgery and irradiation.MethodsBetween January 2015 and December 2017, microsurgical head and neck reconstruction was performed using the ALT flap and transverse cervical artery (TCA) as the recipient vessel in 15 patients who had undergone previous neck dissections and irradiation for cancer treatment. All patients had a “vessel-depleted neck” resulting from severe scarring and radiation fibrosis. Clinical data of each patient were recorded.ResultsAll ipsilateral TCAs were found to be damage free. Subsequently, free ALT flaps were revascularized using the TCAs. One patient developed venous thrombosis, and another patient developed arterial thrombosis. They were both salvaged within 6 hours postoperatively. No flap failure or mortalities were reported within the 30-day postoperative period. Two patients developed orocutaneous fistula and were further managed with wound care. The mean follow-up time was 11.9 ± 6.0 months (range, 5–23 months). Five patients died during the follow-up period from cancer progression.ConclusionsThe use of the free ALT flap and TCA as the recipient vessel provides favorable microsurgical outcomes in patients with depleted recipient vessels in the head and neck region caused by previous neck dissections and radiation therapy.

IntroductionComposite and large head and neck defects requiring extensive skin‐mucosa coverage are often reconstructed by combining flaps. Herein, we present a simple and reliable two‐stage fibula osteocutaneous (FOC) flap technique to improve the survival of a large skin paddle for oromandibular reconstructions.MethodsFrom October 2011 to September 2016, 47 patients with through‐and‐through oromandibular defects were reconstructed using FOC flaps with large skin paddles. To ensure optimum survival of skin paddles, temporary orocutaneous fistula were left in place and closed during the second stage operation via de‐epithelialization of the skin paddle and suturing of mucosa. Demographic data, operative details, and postoperative complications were recorded.ResultsThe skin paddle dimensions ranged from 20 to 31.5 cm in length and 12 to 17 cm in width with an average area of 430.4 cm2 (range 300–504). The average time between the two stages and hospital stay were 10 days and 14 days, respectively. Complications at the donor site included wound dehiscence (n = 3, 6.4%), partial skin graft loss (n = 3, 6.4%) and hematoma (n = 2, 4.3%). Recipient site complications included two (4.3%) early postoperative venous congestions that resolved after elevation and three (6.4%) partial skin flap necrosis (less than 5% surface area). All complications resolved with bedside conservative management. There was only one take‐back for evacuation of recipient site hematoma (2.1%) but no flap loss.ConclusionTwo‐staged large skin paddle FOC flaps can simplify reconstruction of extensive oromandibular defects by improving the reliability of the sizable skin paddle and negating the need for a second flap.

AbstractIntroductionMicrosurgical reconstruction of complex head and neck defects often requires reliable tissue in multiple spatial configurations to achieve good functional and aesthetic outcomes. In addition to robust perforators, flap inset and wound closure require great caution to minimize complications especially in the presence of trismus with limited space for inset. This report describes the technique and results of our staged approach to flap inset which increases the chance of total flap survival in complex head and neck reconstructions.MethodsFrom February 2010 to August 2016, a total of 53 patients were identified via a retrospective chart review. Patients who were suspected to have a high risk of vascular compromise and subsequently underwent complex head and neck reconstruction with staged inset of anterolateral thigh (ALT) flaps were included. The flap was inset only partially at the recipient site initially with fewer sutures. At a second stage, after neovascularization from surrounding tissue was established, the flap was partially elevated, divided and mobilized on its own pedicle for definitive inset.ResultsFifty‐one patients had complete survival of flaps and had uneventful postoperative course. Six cases required immediate re‐exploration to release wound tension or reposition the pedicle. Of these, 4 flaps were salvaged, 2 failed due to small perforators despite anastomosis revision. The flap survival rate was 96.2% and the average time between 2 stages was 24 days (range, 21–28).ConclusionStaged flap inset can improve free flap survival in complex head and neck reconstructions.

ABSTRACT The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell‐released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV‐associated functional activities. Finally, a checklist is provided with summaries of key points.

Background The utility of early postoperative ultrasound measurements in predicting arteriovenous fistula (AVF) clinical maturation is uncertain. Methods We investigated the relationships of ultrasound parameters with AVF clinical maturation in newly created AVF, measured at 1 day and 2 and 6 weeks, in 602 participants of a multicenter, observational cohort study. A backward elimination algorithm identified ultrasound measurements that independently predicted unassisted and overall AVF maturation. Candidate variables included AVF blood flow, diameter, and depth, upper arm arterial diameter, presence of stenosis, presence of accessory veins, seven case-mix factors (age, sex, black race, AVF location, diabetes, dialysis status, and body mass index), and clinical center. We evaluated the accuracy of the resulting models for clinical prediction. Results At each ultrasound measurement time, AVF blood flow, diameter, and depth each predicted in a statistically significant manner both unassisted and overall clinical maturation. Moreover, neither the remaining ultrasound parameters nor case-mix factors were associated with clinical AVF maturation after accounting for blood flow, diameter, and depth, although maturation probabilities differed among clinical centers before and after accounting for these parameters. The crossvalidated area under the receiver operating characteristic curve for models constructed using these three ultrasound parameters was 0.69, 0.74, and 0.79 at 1 day and 2 and 6 weeks, respectively, for unassisted AVF clinical maturation and 0.69, 0.71, and 0.76, respectively, for overall AVF maturation. Conclusions AVF blood flow, diameter, and depth moderately predicted unassisted and overall AVF clinical maturation. The other factors considered did not further improve AVF maturation prediction.