advancing safety in ct-guided biopsies: a case study of the stylet-free coaxial needle technique for displacement of non-target tissues

Background: computed tomography (ct)-guided percutaneous biopsy is a well-established, minimally invasive, and cost-effective diagnostic tool for abdominal lesions. however, anatomical challenges, particularly from adjacent bowel loops and vital structures, can complicate the needle trajectory and increase procedural risk. various techniques have been proposed to mitigate these risks in ct-guided biopsy. among them, the use of a stylet-free coaxial needle offers a practical and versatile approach for safely displacing non-target tissues without additional instruments. case presentation: an 85-year-old male patient with an incidentally detected hypovascular renal mass underwent ct-guided percutaneous biopsy for histopathological diagnosis. during the procedure, a 19-gauge coaxial needle was introduced via the right abdominal wall. however, the planned trajectory was obstructed by a segment of the colon. to avoid bowel injury, the stylet was removed, and the blunt cannula tip of the coaxial needle was used to gently displace the obstructing bowel segment under ct guidance. after multiple controlled attempts, the colon was successfully repositioned, enabling safe advancement of the biopsy needle into the lesion. the biopsy was completed without direct injury to the bowel. post-procedural ct revealed no pneumoperitoneum or immediate complications. conclusion: the stylet-free coaxial needle technique offers a practical and effective approach for displacing anatomical obstructions during ct-guided biopsy using standard equipment. while initial results are promising, further studies are required to confirm its safety and broader clinical applicability.