Comparison of the Analgesic Efficacy of Lidocaine/Prilocaine (EMLA) Cream and Needle-Free Delivery of Lidocaine During Fine-Needle Aspiration Biopsy of Thyroid Nodules/Tiroid Nodullerinin Ince Igne Aspirasyon Biyopsisi Sirasinda Lidokain/Prilokain (EMLA) Krem Ve Lidokainin Ignesiz Enjeksiyonunun Analjezik Etkinliklerinin Karsilastirilmasi (Original Article/Orijinal Makale) (Report‪)‬

Introduction Fine-needle aspiration biopsy (FNAB) of thyroid nodules has long been established as an effective, reliable, and safe procedure causing minor discomfort and slight temporary pain (1). It is intuitive that a potential painful procedure should require some form of anesthesia. FNAB is sometimes perceived as an uncomfortable and stressful procedure, especially for those who are pain phobic. Efficacy of the needle-free injection of lidocaine and eutectic mixture of local anesthetic (EMLA) cream, which consists of a combination of lidocaine 2.5% and prilocaine 2.5%, for reducing the pain associated with cutaneous procedures and FNAB of thyroid nodules has been established in prospective, randomized placebo-controlled trials (2-5). However, obstacles were present for each form of medication. EMLA requires a longer application time (at least 1 hour); needle-free application of lidocaine requires only a few minutes. Although a very tiny amount of anesthetic material (0.3 mL) is sealed inside, a major concern related to needle-free injection of lidocaine is tissue swelling at biopsy site after injection. This might interfere with subsequent imaging and the targeting of an underlying thyroid nodule resulting in inadequate tissue sample.