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Palpable thyroid nodules are present in approximately 5–7% of the adult population, and of these, only a small percentage (5–10%) harbor malignancy. Ultrasound (US) imaging of the neck is typically used to characterize thyroid nodules in order to triage lesions with the highest risk of malignancy. Fine needle aspiration (FNA) is recommended for thyroid lesions with radiographically suspicious features (as outlined below). FNA biopsy of the thyroid gland is an increasingly common procedure, with approximately 300,000–500,000 biopsies performed annually in the United States. The 2015 American Thyroid Association management guidelines underscore the importance of radiologic risk stratification.

Electrical components used in LED lighting devices have a significant impact on the reliability of lighting systems. Understanding the reliability of LED drivers requires a knowledge of the intended use of the device including environmental (e.g., temperature, humidity), electrical (i.e., voltage quality and transients), and mechanical (i.e., vibration) stresses that the products would experience. In addition, knowledge of the susceptibility of key electronic components (e.g., capacitors, switching transistors, diodes, ICs, and linear components) to these stresses is also important in understanding overall product reliability. Although this information is difficult to determine for an electronic assembly such as the LED lighting driver, accelerated tests can help provide insights regarding likely failure modes and provide a basis to project reliability and product lifetime. In this chapter we have investigated common failure modes in LED drivers under accelerated testing conditions.