An EUS-FNA (Endoscopic Ultrasound-Guided Fine Needle Aspiration) needle is a specialized medical device used in conjunction with an endoscope to collect tissue samples from lesions in the gastrointestinal tract and surrounding organs.

Key Features of EUS-FNA Needles
Needle Sizes: Available in various gauges, commonly 19G, 22G, and 25G. The choice of needle size depends on the target lesion and the desired tissue sample quality.
19G Needles: Thicker, providing larger tissue samples but less flexible.
22G and 25G Needles: Thinner, more flexible, and suitable for lesions requiring precise targeting or tight angulation.
Materials: Needles are typically made from materials like stainless steel or Nitinol, offering durability and flexibility.
Stylet: Many needles include a stiff stylet inside the needle, which helps maintain the needle’s shape during insertion and can be removed to facilitate aspiration.
Tip Design: The tip of the stylet is often blunted to reduce trauma during insertion.

Advantages
Minimally Invasive: EUS-FNA is less invasive compared to surgical biopsies, reducing recovery time and complications.
High Diagnostic Yield: Provides high-quality tissue samples for cytological or histological examination, aiding in accurate diagnosis and staging of diseases.