Management of the brachial plexus in head and neck cancer

Purpose of reviewThe brachial plexus is an important anatomical structure that is regularly encountered by head and neck surgeons and radiation oncologists. Surgical or radiation-induced brachial plexus injury have great impact on arm function and quality of life. Anatomical variations and management of the brachial plexus in head and neck cancer treatment are discussed.Recent findingsThe brachial plexus consists of spinal roots from C5-C8 and T1. The most prevalent anatomical variations in brachial plexus anatomy include the prefixed brachial plexus (additional contribution from C4) in 11%, the roots of C5 and C6 piercing the belly of the anterior scalene muscle in 6.8%, and presence of the scalenus minimus muscle in 4.1-46%. Due to its location, the brachial plexus is at risk of inadvertent division or neuropraxia during surgical procedures such as neck dissection or robot-assisted transaxillary thyroid surgery (RATS). In case of inadvertent division, nerve reconstruction surgery is warranted and may lead to improved function. The risk of radiation-induced brachial plexus injury is dose-dependent and occurs in approximately 12-22%. Currently, no successful treatment options exist for radiation-induced injury.SummaryKnowledge of anatomical variations is important for head and neck surgeons to minimize the risk of brachial plexus injury. Limiting radiation therapy dose to the brachial plexus is desirable to decrease the risk of brachial plexus injury

Daphnid Life Cycle Responses to New Generation Flame Retardants

Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea Daphnia magna of two HFFRs, aluminum diethylphosphinate (ALPI) and 9,10-dihyro-9-oxa-10-phosphaphenanthrene-oxide (DOPO). The toxicity of ALPI increased from a 48 h LC50 of 18 mg L-1 to a 21 day LC50 value of 3.2 mg L-1, resulting in an acute-to-chronic ratio of 5.6. This may imply a change in classification from low to moderate toxicity. ALPI also affected sublethal life cycle parameters, with an EC50 of 2.8 mg L-1 for cumulative reproductive output and of 3.4 mg L-1 for population growth rate, revealing a nonspecific mode of action. DOPO showed only sublethal effects with an EC50 value of 48 mg L-1 for cumulative reproductive output and an EC50 value of 73 mg L-1 for population growth rate. The toxicity of DOPO to D. magna was classified as low and likely occurred above environmentally relevant concentrations, but we identified specific effects on reproduction. Given the low chronic toxicity of DOPO and the moderate toxicity of ALPI, based on this study only, DOPO seems to be more suitable than ALPI for BFR replacement in polymers