A speculum is a medical instrument that is typically used to widen body cavity or passage openings, such as the vagina, anus, ear, or nostrils. When conducting a speculum exam, a doctor or other medical professional may use the tool to help with viewing a patient’s interior parts. In addition, the devices can be used to hold a body passage or cavity open so that a sample of cells or other matter can be taken. In Latin, the term means "mirror."
Specula are available in an assortment of different sizes and shapes, depending on their specific purpose. Most are made out of metal that can be sterilized after use. Some specula, particularly those used in emergency rooms, are made from plastic and are intended for one-time use. In some cases, the instrument contains a tube that permits the user to directly look at the patient’s internal area.
One of the most common types of specula is a vaginal speculum, which comes in a range of different sizes. This instrument dilates the vagina, allowing a gynecologist to more easily see a patient’s cervix. There are a wide variety of vaginal specula that can be used by a gynecologist to perform an examination. Most of these devices have two blades and a handle. Once the blades are clicked into place, the handle can be locked by fastening a screw.
Many gynecologists use either the Graves or the Pederson pelvic exam speculum. The Graves is usually 3 to 4.75 inches (approximately 7.6 to 12.1 centimeters) in length, and it generally contains blades that are 0.5 to 1.5 inches wide (about 1.3 to 3.8 centimeters). Its inferior blade is generally longer than its superior blade, and it is often used on women who are sexually active. The Pederson speculum, on the other hand, typically has a more tapered shape with narrower and flatter blades. Due to its small size, the Pederson instrument is commonly used on pediatric or elderly patients, as well as patients who have never been sexually active.
Another well-known kind of specula is the aural or ear speculum. Usually shaped like a small funnel, it allows a user to see inside the ear canal for the purpose of examining the ear drum. Similarly, nasal specula allow for viewing inside the nostrils. These devices are typically hinged and have two flat blades with a handle. The blades are generally inserted into the nostrils and, when the handle is squeezed together, the blades spread and open the nostrils for examination.