What is the purpose of the forward/reverse knob on an automatic injector?

The forward/reverse knob on an automatic injector primarily serves to create a wet-to-wet connection to the catheter. This is essential in interventional procedures to ensure that the catheter and the injector maintain an uninterrupted flow of the contrast agent. When the knob is engaged to the forward position, it aids in pushing the contrast agent into the catheter for accurate delivery into the patient’s vascular system. When set to the reverse position, it prevents the backflow of fluid, thus maintaining the integrity of the system while ensuring that the injection is efficient and safe.

Creating a wet-to-wet connection minimizes the risk of air entering the system, which is critical during imaging procedures to prevent artifacts and ensure high-quality diagnostic images. Maintaining a continuous fluid pathway is foundational to the reliability of automated injectors, enhancing the efficacy of the imaging process and patient safety.