| Discussion: The hyperechoic lesions at the bladder base on the U/S represent subureteric chondrocyte mounds formed secondary to the deflux procedure. They may be multilobed or unilobed.
The absence of a subureteric chondrocyte mound or the presence of a multilobed mound contour is associated with persistent reflux.
More on the Deflux procedure: In late 2001, the FDA approved a dextranomer/hyaluronic acid copolymer (Deflux), made of dextranomer microspheres (80–250 nm) that are suspended in a gel of non-animal stabilized hyaluronic acid for use in Grade II through IV VUR in children older than one year of age. The copolymer has been used in Europe since 1998. Both of these substances are polysaccharides, and the non-animal stabilized hyaluronic acid is very similar to the natural hyaluronic acid found in the body. Dextranomer and hyaluronic acid are biodegradable and lack allergenic or immunogenic properties.
During an endoscopic procedure, Deflux is injected into the submucosal area next to the ureter-bladder junction. At this point at the junction, the substance forms a one-way valve, overcoming the backflow pressure from the bladder. The dextranomer facilitates the growth of fibroblasts and collagen between the microspheres as the hyaluronic acid degrades. The artificial valve is consolidated with endogenous tissue that stabilizes the bulk effect for a sustained response.
Initial studies have demonstrated resolution rates of 66 percent to 77 percent. Depending on the grade and age of patient, this is approximately double the rate of resolution compared with antibiotic treatment and is nearly the same as open surgical treatment. Longer-term observation of patients demonstrated that as many as 96 percent of ureters that were free of grade III or greater reflux from three to twelve months after treatment were still free of reflux two to five years post-injection.
The retail cost of the material is $925 per vial, with one vial used for each ureter that is affected by reflux. The procedure is performed on an outpatient basis, with the patient given mild anesthesia and, barring complications, same-day discharge. This is much less expensive than the open surgical procedure, which requires several days in the hospital and exposes the child to all of the potential complications, such as scarring, infection, and prolonged recovery. In addition, the long term net cost is actually less than chronic antibiotic use.
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