What surgical instrument is used to enlarge the punctum?

The instrument used to enlarge the punctum is a dilator. Dilators are specifically designed to gradually expand or widen openings in the body, including the punctum, which is the tiny opening of the tear ducts. By using a dilator, a practitioner can effectively increase the size of the punctum, allowing for improved drainage of tears or for other medical procedures related to the ocular system.

The other instruments mentioned do serve specific functions; for instance, probes are typically used to explore or clear passageways but do not specifically enlarge openings. Scissors are meant for cutting rather than expanding tissue. A shutter, while not a standard term in surgical instruments, generally refers to mechanisms that open or close, which would not apply to the action of enlarging a punctum. Thus, the dilator’s design and function directly align with the task of enlarging the punctum, making it the correct choice.