[Composition and morphology of stones in enlarged prostatic utricle].

OBJECTIVE

To investigate the composition and morphology of the stones in the enlarged prostatic utricle (EPU).

METHODS

We took out 36 EPU stones from 11 patients by transurethral fenestration between 1992 and 2011, and analyzed the stones by scanning electron microscopy, x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIS).

RESULTS

Under the scanning electron microscope, all the EPU stones were constituted of many intensive minicrystals and amorphous matrix. XRD and FTIS revealed that all were hydroxyapatite crystal.

CONCLUSION

EPU stones belong to the category of prostatic pseudo-calculi, whose formation is ascribed not to the abnormal change of urine composition, but to the continuous secretion, absorption and concentration of EPU liquid and ablated epithelial cells from the EPU.