Do ureteric calculi necessarily produce obstruction to the passage of urine in the ureters? These ultrasound and color Doppler images study just this fact..
Observe the ultrasound image of the urinary bladder below: a right vesico-ureteric junction calculus is clearly visible. The patient had severe right ureteral colic too. The right VUJ calculus measures 6 mm. in size.
Color Doppler image shows almost normal right ureteral jet, despite the calculus at the ureteric orifice.
Yet another Doppler image shows another jet emanating from the right ureteric orifice.
The right kidney appears normal- no evidence of obstructive changes here.
The conclusion: small ureteric calculi can produce almost no obstructive changes despite being located at the narrow ureteral orifice into the bladder. But repeated studies by me show this is an exception, rather than the rule. Most ureteral calculi produce partial or major obstruction in the affected ureter. See: http://www.ultrasound-images.com/ureteric-calculi.htm