Final answer:
The uterine cavity is filled with a liquid like saline during a hysteroscopy to expand the uterus and allow for better visualization of its interior for diagnostic or surgical purposes.
Step-by-step explanation:
This procedure is often performed using a hysteroscope. In this procedure, the uterine cavity is filled with a liquid such as saline or a similar distension medium. A hysteroscope is a medical instrument with a camera attached that is used to examine the inside of the uterus. During the procedure, the uterus is expanded with the liquid, allowing the doctor to have a clear view inside the uterine cavity. This is crucial for procedures such as diagnosing or treating abnormal bleeding, removal of fibroids (myomectomy), and investigating fertility issues.
For instance, during a diagnostic hysteroscopy, which might be looking for potential causes of infertility or recurrent miscarriages, filling the uterine cavity with fluid helps reveal the internal structure of the uterus. Surgical hysteroscopy may require the same step before any corrective processes, such as the removal of fibroids or polyps, can take place.