title: Predicting the mineral composition of ureteral stone using non-contrast computed tomography.
abstract: We investigated the correlation between computed tomography (CT) density of ureteral stones and their mineral composition. A total of 346 patients who underwent ureteroscopic lithotripsy for calculi all fragments of which were acquired at a single institution from 2009 to 2011 were analyzed. The maximum and mean CT densities were measured preoperatively. A mineral analysis revealed calcium oxalate in 203 (58.7 %), mixed calcium oxalate and calcium phosphate in 78 (23.0 %), calcium phosphate in 18 (5.2 %), uric acid in 8 (2.3 %), struvite in 3 (0.9 %), and cysteine in 5 (1.4 %). The mean Hounsfield units (HUs) of the CT density were 1046 HUs in calcium oxalate, 1101 HUs in mixed calcium oxalate and calcium phosphate, 835 HUs in calcium phosphate, 549 HUs in uric acid, 729 HUs in struvite, and 698 HUs in cystine. The HUs in calcium oxalate were significantly higher than those in uric acid (p < 0.01) and struvite (p < 0.01). Those in monohydrate stones were significantly higher, compared with dehydrate stones (p < 0.05). We analyzed the largest number of stones than each published study to correlate their mineral composition and CT density. Calcium component stones showed significantly higher CT densities than other types.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA. takashi_tk2001@yahoo.co.jp.|Department of Urology, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, Kanagawa, Japan. takashi_tk2001@yahoo.co.jp.|Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan. takashi_tk2001@yahoo.co.jp.
authors.forename: Takashi
authors.identifier: http://orcid.org/0000-0002-7049-3379
authors.initials: T
authors.lastname: Kawahara
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyamoto
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, Kanagawa, Japan.|Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ito
authors.affiliation: Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Terao
authors.affiliation: Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Kakizoe
authors.affiliation: Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan.
authors.forename: Yoshitake
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ishiguro
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, Kanagawa, Japan.
authors.forename: Hiroji
authors.initials: H
authors.lastname: Uemura
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, Kanagawa, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yao
authors.affiliation: Department of Urology, Ohguchi Higashi General Hospital, Yokohama, Kanagawa, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Matsuzaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed; D014514:Ureteral Calculi / Q000737:chemistry* / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: Calcium; Computed tomography; Stone composition; Ureter stone; Ureteral calculi; Ureteroscopic lithotripsy; Ureteroscopy