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What is Ureterocele and explain in detail?
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.
Since the advent of the ultrasound, most ureteroceles are diagnosed prenatally. The pediatric and adult conditions are often found incidentally, i.e. through diagnostic imaging performed for unrelated reasons.

Classification
Intravesical
Confined within the bladder
Ectopic
Some part extends to the bladder neck or urethra
Stenotic
Intravesical ureterocele with a narrow opening
Sphincteric
Ectopic ureterocele with an orifice distal to the bladder neck
Sphincterostenotic
Orifice is both stenotic and distal to the bladder neck
Cecoureterocele
Ectopic ureterocele that extends into the urethra, but the orifice is in the bladder

Signs and symptoms
The signs and symptoms of ureterocele in the latter two forms can easily be confused with other medical conditions. Symptoms can include:
Frequent urinary tract infections
Pyelonephritis
Obstructive voiding symptoms
Urinary retention
Failure to thrive
Hematuria
Cyclic abdominal pain
Urolithiasis
Cobra head sign is seen in radiography
In females: salpingitis, hydrosalpinx with sepsis or torsion