Megaureter

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Megaureter
Specialty Urology

Megaureter is a medical anomaly whereby the ureter is abnormally dilated. Congenital megaureter is an uncommon condition which is more common in males, may be bilateral, and is often associated with other congenital anomalies. The cause is thought to be aperistalsis of the distal ureter, leading to dilatation. [ citation needed ]

The cutoff value for megaureter is when it is wider than 6 [1] or 7 mm. [2]

A functional obstruction at the lower end of the ureter leads to progressive dilatation and a tendency to infection. The ureteric orifice appears normal and a ureteric catheter passes easily.[ citation needed ]

Definitive surgical treatment involves refashioning the lower end of the affected ureter so that a tunnelled reimplantation into the bladder can be done to prevent reflux.[ citation needed ]

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A ureterocele is a congenital abnormality found in the ureter. In this condition the distal ureter balloons at its opening into the bladder, forming a sac-like pouch. It is most often associated with a duplicated collection system, where two ureters drain their respective kidney instead of one. Simple ureterocele, where the condition involves only a single ureter, represents only twenty percent of cases.

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Vesicoureteral reflux Medical condition

Vesicoureteral reflux (VUR), also known as vesicoureteric reflux, is a condition in which urine flows retrograde, or backward, from the bladder into one or both ureters and then to the renal calyx or kidneys. Urine normally travels in one direction from the kidneys to the bladder via the ureters, with a 1-way valve at the vesicoureteral (ureteral-bladder) junction preventing backflow. The valve is formed by oblique tunneling of the distal ureter through the wall of the bladder, creating a short length of ureter (1–2 cm) that can be compressed as the bladder fills. Reflux occurs if the ureter enters the bladder without sufficient tunneling, i.e., too "end-on".

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Reflux nephropathy is kidney damage (nephropathy) due to urine flowing backward (reflux) from the bladder toward the kidneys; the latter is called vesicoureteral reflux (VUR). Longstanding VUR can result in small and scarred kidneys during the first five years of life in affected children. The end results of reflux nephropathy can include high blood pressure, excessive protein loss in the urine, and eventually kidney failure.

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Ectopic ureter is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence. Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans.

Congenital stenosis of vena cava Medical condition

Congenital stenosis of vena cava is a congenital anomaly in which the superior vena cava or inferior vena cava has an aberrant interruption or coarctation.

Bladder outlet obstruction occurs when urine is unable to flow from the kidneys through the ureters and out of the bladder through the urethra. Decreased flow of urine leads to swelling of the urinary tract, called hydronephrosis. This process of decreased flow of urine through the urinary tract can begin as early as during intrauterine life and it prevents normal development of fetal kidneys and fetal urine. Low levels of fetal urine leads to low amniotic fluid levels and incomplete lung maturation. Older children and adults can also experience bladder outlet obstruction; however, this process is usually reversible and isn't associated with as many poor outcomes as in infants with congenital bladder outlet obstruction.

Duplicated ureter

Duplicated ureter or Duplex Collecting System is a congenital condition in which the ureteric bud, the embryological origin of the ureter, splits, resulting in two ureters draining a single kidney. It is the most common renal abnormality, occurring in approximately 1% of the population.

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A ureteric balloon catheter is a balloon catheter intended for treating strictures of the ureter. In fact it is a double J stent on which a balloon is mounted. It is connected to a delivery device (pusher) to introduce it from the bladder into the ureter. The system comprises a non-return valve device, and a pusher with a stylet and two ports.

Renal ultrasonography

Renal ultrasonography is the examination of one or both kidneys using medical ultrasound.

References

  1. "Enlarged ureter". Greifswald Medical School . Archived from the original on 2017-02-07. Retrieved 2017-02-06.CS1 maint: discouraged parameter (link)
  2. Page 140 in: Mitchell E. Tublin (2015). Diagnostic Imaging: Genitourinary E-Book. Edition 3. Elsevier Health Sciences. ISBN   9780323400428.
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