Can a dual-energy computed tomography predict unsuitable stone components for extracorporeal shock wave lithotripsy?.
10.4111/kju.2015.56.9.644
- Author:
Sung Hoon AHN
1
;
Tae Hoon OH
;
Ill Young SEO
Author Information
1. Department of Urology, Institute of Wonkwang Medical Science, Wonkwang University School of Medicine, Iksan, Korea. seraph@wku.ac.kr
- Publication Type:Original Article
- Keywords:
Calcium oxalate;
Uric acid;
Urinary calculi;
X-ray computed tomography
- MeSH:
Adult;
Aged;
Calcium Oxalate/analysis;
Female;
Humans;
Kidney Calculi/*chemistry/*radiography/therapy;
*Lithotripsy;
Male;
Middle Aged;
Patient Selection;
Radiography, Dual-Energy Scanned Projection;
Tomography, X-Ray Computed/*methods;
Ureteral Calculi/*chemistry/*radiography/therapy;
Uric Acid/analysis
- From:Korean Journal of Urology
2015;56(9):644-649
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: To assess the potential of dual-energy computed tomography (DECT) to identify urinary stone components, particularly uric acid and calcium oxalate monohydrate, which are unsuitable for extracorporeal shock wave lithotripsy (ESWL). MATERIALS AND METHODS: This clinical study included 246 patients who underwent removal of urinary stones and an analysis of stone components between November 2009 and August 2013. All patients received preoperative DECT using two energy values (80 kVp and 140 kVp). Hounsfield units (HU) were measured and matched to the stone component. RESULTS: Significant differences in HU values were observed between uric acid and nonuric acid stones at the 80 and 140 kVp energy values (p<0.001). All uric acid stones were red on color-coded DECT images, whereas 96.3% of the nonuric acid stones were blue. Patients with calcium oxalate stones were divided into two groups according to the amount of monohydrate (calcium oxalate monohydrate group: monohydrate> or =90%, calcium oxalate dihydrate group: monohydrate<90%). Significant differences in HU values were detected between the two groups at both energy values (p<0.001). CONCLUSIONS: DECT improved the characterization of urinary stone components and was a useful method for identifying uric acid and calcium oxalate monohydrate stones, which are unsuitable for ESWL.
