Certified Surgical Technologist (CST) Exam 2026 – 400 Free Practice Questions to Pass the Exam

The correct answer is the nasolacrimal duct. In pediatric patients, upper respiratory infections often lead to obstruction or inflammation of the nasolacrimal duct, which can cause symptoms such as excessive tearing or purulent discharge from the eyes. If these symptoms persist, probing and dilation of the nasolacrimal duct may be required to clear any blockages and relieve the condition.

The other options relate to structures that may be affected by upper respiratory infections but do not typically require probing and dilation as a first-line intervention for management. For example, while sinus cavities may become congested or infected during an upper respiratory infection, they are generally treated with medications rather than invasive procedures. The Eustachian tube can also become blocked, leading to middle ear issues; however, manipulation of this structure usually involves addressing the underlying infection rather than direct probing. The tympanic membrane is involved in the transmission of sound and can be affected by infections, but it does not undergo probing and dilation in the context of upper respiratory infections.