Revision 3 for 'Calyceal diverticulum'All Revisions
Calyceal Diverticulum or Pyelocalyceal diverticulum is almost congenital urine-filled out pouching from renal calyx or pelvis into the renal cortex. A little percentage of cases may be acquired. It is lined with transitional epithelium.
Type 1:the more common, communicates with a minor calyx.
Type 2 : communicates with a major calyx or the renal pelvis.
A relatively uncommon , seen in 0.21% to 0.6% of intravenous urograms (IVU),but high incidence of stone formation due to urine stagnation. women more commonly affected than men (2:1). they are found in the upper pole calyces ~50% , in the middle ~ 30% and lower poles ~20%.
The most common theory is congenital origin of diverticulum results from failure of regression of the third- and fourth-generation ureteric buds., resulting from obstructing stones or infection.
Complications are due to urine stasis:
milk of calcium.
Radiographic features :
Plain abdominal radiographs : +/- a half moon or meniscus-shaped calcification of radio-opaque milk of calcium.
at ultrasound , MRI, and non-enhanced or nephrographic phase contrast-enhanced CT: the Appearance is similar to that of a simple cyst.The diagnosis is made with certainty in the excretory phase of imaging, the cystic structure fills with contrast material due to communication with pelvi-calyces, and layering of contrast material is seen within.
A calyceal diverticulum complicated by calculi or layered dependent milk of calcium appears echogenic on ultrasound and high-attenuating material on unenhanced CT with fluid milk level.
the following differential diagnosis have no communication with collecting system :