Final answer:
The surgical instrument with a hollow barrel through the center is called an endoscope. It is used in medical procedures to explore the body and perform surgeries through various orifices or incisions. The endoscope has a hollow barrel and fiber optic cables to transmit light and images.
Step-by-step explanation:
The surgical instrument with a hollow barrel through the center is called an endoscope. An endoscope is a device used in medical procedures to explore the body through various orifices or minor incisions. It has a hollow barrel that allows instruments to be inserted and observed inside the body. The endoscope is equipped with fiber optic cables that transmit light and images to the doctor performing the procedure.