the veterinarian may also employ endoscopy for detailed evaulation, in which he or she will look directly into the stomach and duodenum using an endoscope, a rigid or flexible tube that is inserted into the stomach and duodenum to visually inspect and take pictures of the region.

How would the previous sentence be correctly capitalized?
The veterinarian may also employ endoscopy for detailed evaulation, in which he or she will look directly into the stomach and duodenum using an endoscope, a rigid or flexible tube that is inserted into the stomach and duodenum to visually inspect and take pictures of the region.