Kidney stones (ureterolithiasis) result from stones or renal calculi in the ureter. The stones are solid concretions or calculi (crystal aggregations) formed in the kidneys from dissolved urinary minerals. Nephrolithiasis refers to the condition of having kidney stones. Urolithiasis refers to the condition of having calculi in the urinary tract (which also includes the kidneys), which may form or pass into the urinary bladder. Ureterolithiasis is the condition of having a calculus in the ureter, the tube connecting the kidneys and the bladder. The term bladder stones usually applies to urolithiasis of the bladder in non-human animals such as dogs and cats.
Duplicated ureter is a congenital condition in which the ureteric bud, the embryological origin of the ureter, splits (or arises twice), resulting in two ureters draining a single kidney. It is the most common renal abnormality, occurring in approximately 1% of the population. The additional ureter may result in a ureterocele, or an ectopic ureter.
When empty, the bladder lies on the pelvic floor surrounded by extraperiotoneal fatty tissue, posterior to the pubic bones. As it fills, it ascends in the extraperitoneal fatty tissue and enters the greater pelvis, reaching as high as the level of the umbilicus when full. In males, it is situated anterior to the rectum and superior to the prostate gland. In females, it is anterior to the vagina and anteroinferior to the uterus.
The anterior portion of the bladder, the apex, is connected to the medial umbilical ligament (vestigal urachus). The superior surface is covered with peritoneum. There are two inferolateral surfaces, a base, and a neck.
The body of the bladder extends from the apex to the posterior end, the fundus. The ureters enter the bladder through the internal ureteric orifices at the posterolateral angles of the trigone, which is located at the posterior base of the bladder and extends inferiorly to its anteroinferior angle at the neck of the bladder and the internal urethral orifice.
The ureters exit medially from the kidney at the renal hilum posterior to the renal vessels , then course inferomedially along the psoas major muscle and transverse processes of the lumbar vertebrae. They cross the external iliac artery just distal to the bifurcation of the common iliac, then course along the lateral wall of the pelvis to empty into the posterior aspect of the urinary bladder at the bladder trigone.
Blood is supplied by the ureteral branches of renal and testicular or ovarian arteries, and abdominal aorta. Renal and testicular or ovarian veins supply venous drainage.
Number of View: 1192