Factors Influencing Inadequacy in Rapid Onsite Evaluation of Ultrasound Guided Fine Needle Aspiration (FNA) Samples of Thyroid Nodules

All FNAs will be performed by experienced radiologists (of 5-year experience in thyroid FNA procedures). Patients will be positioned comfortably, typically in a supine position with neck extension after putting a pillow under shoulders to fully expose the patient's neck to allow optimal access to the nodule. Ultrasound guidance using Logic E9 machine (GE Healthcare, Chicago, IL, USA) or Sonoscape X5 Portable Ultrasound machine with high-frequency linear array probes (3-12 MHz) will be used to visualize the nodule accurately and guide needle placement. 5ml syringe with 21G needle, 3ml syringe with 23G needle or 22G Quincke tip spinal needle will be used for FNA. Needle insertion will be directed either trans-isthmic or lateral cervical approach. Aspirations will be conducted at different angles and within different nodule regions using a to-and-fro motion till getting blood stain in the needle hub to obtain representative samples. Maximum number of four passes will be performed .