Korean J Urol.  2006 Jan;47(1):70-74. 10.4111/kju.2006.47.1.70.

Hounsfield Units of Urinary Calculi as a Predictor of the Therapeutic Effect of Extracorporeal Shockwave Lithotripsy

• Chae HS
• Lee SH

• KMID: 2294218
• DOI: http://doi.org/10.4111/kju.2006.47.1.70

Abstract

PURPOSE: Non-enhanced spiral computed tomography (NESCT) has become the preferred method for imaging urinary calculi. We evaluated the Hounsfield units (HU) of urinary calculi on NESCT as a predictor of the therapeutic effect of extracorporeal shockwave lithotripsy (ESWL).
MATERIALS AND METHODS
We evaluated 72 patients with urinary calculi who underwent ESWL. The HUs of calculi were measured on the pretreatment NESCT and at post-treatment via radiographic assessment. The patients were divided into 2 groups, the response group (n=39): the patients with remnant calculi less than 3mm or they were without remnant calculi, and the non-response group (n=33): the patients with remnant calculi greater than 3mm. The HUs of the response and non-response groups were then compared.
RESULTS
The HUs of the response and non-response groups were 529.7+/-168.2 and 814+/-116.6, respectively, and the HUs of the non-response group was significantly higher than that of the non-response group.
CONCLUSIONS
The HU of urinary calculi, as seen on NESCT, can help to predict the therapeutic effect of ESWL and also select the most effective treatment modalities for the patients suffering with urinary calculi.

Keyword

Urinary calculi; Tomography; Lithotripsy

MeSH Terms

Calculi
Humans
Lithotripsy*
Tomography, Spiral Computed
Urinary Calculi*

Figure

• 

  Fig. 1 (A) One calculus is demonstrated in right upper ureter. (B) The mean Hounsfield unit (HU) values in the selected area is measured.

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