Ureter

Urinary system

The ureter is a vital component of the human urinary system, serving as the conduit for urine transport from the kidneys to the urinary bladder. There are two ureters in the human body, with each extending from its respective kidney to funnel urine into the bladder.

Anatomy

Each ureter is a narrow, tubular structure that averages about 25-30 cm in length. Anatomically, it can be segmented into three parts:

• Pelvic Ureter: The part closest to the kidney.
• Abdominal Ureter: The mid-section that descends anterior to the psoas major muscle.
• Intravesical Ureter: The segment that enters into the urinary bladder.
• The ureters contain a layer of smooth muscle, which contracts in coordinated waves of peristalsis to propel urine from the kidneys to the bladder.

Physiology

The primary function of the ureter is to ensure the unidirectional flow of urine from the kidneys to the urinary bladder. The peristaltic contractions in the ureter facilitate this movement, which occurs irrespective of the body's position. The point where the ureter enters the bladder is critical in preventing a reflux of urine back into the ureter and kidneys. This is due to the oblique angle at which the ureter traverses the bladder wall, creating a one-way valve effect.

Clinical Relevance

• Ureteral stones: These are solid particles that form from substances in the urine and may get lodged in the ureter, causing pain and obstructing urine flow.
• Ureteral stricture: A narrowing or blockage of the ureter due to injury, surgery, or a disease.
• Ureteral injuries: Traumatic events or surgical complications can lead to injury of the ureter.
• Vesicoureteral reflux (VUR]]: A condition wherein urine from the bladder flows backward into the ureters, often due to a defect at the junction where the ureter joins the bladder.

Diagnostic Tests and Procedures

The ureter's health and functionality can be assessed through several diagnostic tests and procedures, including:

• Intravenous pyelogram (IVP): A type of X-ray examination that visualizes the urinary tract after injecting a contrast medium.
• Ureteroscopy: A procedure using a thin, flexible viewing tool (ureteroscope) to examine the ureter.
• CT urogram: A type of CT scan tailored to visualize the urinary tract.

See also

• Kidney
• Urinary bladder
• Urinary system
• Urethra