Dilation

Dilation is a term in medicine that refers to the enlargement, stretching, or expansion of a body part or structure. It is commonly used in the context of blood vessels, the eye's pupil, or the cervix during childbirth.

Blood Vessel Dilation

Blood vessel dilation, also known as vasodilation, is the widening of the blood vessels. This process occurs naturally in the body in response to various conditions, such as low oxygen levels, high temperatures, or increased blood flow demand. Vasodilation helps to increase blood flow and decrease blood pressure.

Pupil Dilation

Pupil dilation, or mydriasis, is the expansion of the pupil of the eye. This can occur in response to low light conditions, excitement, or the use of certain drugs. Pupil dilation allows more light to enter the eye, improving vision in low light conditions.

Cervical Dilation

Cervical dilation is a critical part of the childbirth process. During labor, the cervix dilates, or opens, to allow the baby to pass through the birth canal. Cervical dilation is measured in centimeters, with full dilation being 10 centimeters.

Dilation in Other Contexts

Dilation can also refer to the process of expanding or enlarging an opening, such as in the case of esophageal dilation for the treatment of conditions like achalasia or esophageal stricture. It can also refer to the expansion of a hollow or tubular organ, such as the urethra or esophagus.

See Also

• Vasoconstriction
• Mydriasis
• Effacement