Abstract:
OBJECTIVES:The aim of this study was to investigate the feasibility of kidney stone composition analysis using spectral detector computed tomography scanner (SDCT) with normal- and low-dose imaging protocols. METHODS:A total of 154 stones harvested from nephrolithotripsy or nephrolithotomy with a known monocrystalline composition as determined by infrared spectroscopy were examined in a nonanthropomorphic phantom on an SDCT (IQon, Philips, Best, the Netherlands). Imaging was performed with 120 kVp and (a) 40 mAs and (b) 200 mAs, resulting in a computed tomography dose index (CTDIvol) of 2 and 10 mGy, respectively. Besides conventional CT images (CIs), SDCT enables reconstruction of virtual monoenergetic images (40-200 keV). Spectral coefficient images were calculated by performing a voxel-by-voxel combination of 40 and 200 keV images (Matlab R2017b, Mathworks Inc). All stones were semiautomatically 3D-segmented on CI using a threshold-based algorithm implemented in an offline DICOM viewer. Statistical assessment was performed using Steel-Dwass method to adjust for multiple comparisons. RESULTS:Ca-phosphate (n = 22), Ca-oxalate (n = 82), cysteine (n = 20), struvite (n = 3), uric acid (n = 18), and xanthine stones (n = 9) were included in the analysis. Stone diameter ranged from 3.0 to 13.5 mm. On CI, attenuation differed significantly between calcific and noncalcific stones only (P ≤ 0.05), the spectral coefficient differed significantly between (//): Ca-oxalate//Ca-phosphate//cystine//struvite//uric acid//xanthine in 10 mGy protocol (all P ≤ 0.05). The same results were found for the 2 mGy-protocol, except that differentiation of Ca-oxalate and Ca-phosphate as well as uric acid and xanthine was not possible (P ≥ 0.05). CONCLUSIONS:Spectral detector CT allows for differentiation of kidney stones using semi-automatic segmentation and advanced image post-processing, even in low-dose imaging protocols.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Große Hokamp N,Salem J,Hesse A,Holz JA,Ritter M,Heidenreich A,Maintz D,Haneder Sdoi
10.1097/RLI.0000000000000468subject
Has Abstractpub_date
2018-08-01 00:00:00pages
457-462issue
8eissn
0020-9996issn
1536-0210journal_volume
53pub_type
杂志文章abstract::Receiver operating characteristic (ROC) analysis has been used in a broad variety of medical imaging studies during the past 15 years, and its advantages over more traditional measures of diagnostic performance are now clearly established. But despite the essential simplicity of the approach, workers in the field ofte...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198903000-00012
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abstract:RATIONALE AND OBJECTIVE:The purpose of this study was to investigate the feasibility, efficacy, and safety of ultrasound-guided percutaneous cryotherapy of stage T1 breast cancers. MATERIALS AND METHODS:Thirty patients with biopsy-confirmed breast cancers with tumor diameters of 15 mm or smaller (range, 5-15 mm; media...
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journal_title:Investigative radiology
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journal_title:Investigative radiology
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journal_title:Investigative radiology
pub_type: 杂志文章
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journal_title:Investigative radiology
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journal_title:Investigative radiology
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doi:10.1097/00004424-200006000-00004
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198508000-00014
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journal_title:Investigative radiology
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doi:10.1097/00004424-199510000-00006
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journal_title:Investigative radiology
pub_type: 杂志文章,评审
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journal_title:Investigative radiology
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doi:10.1097/00004424-199201000-00008
更新日期:1992-01-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199106000-00004
更新日期:1991-06-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199112000-00007
更新日期:1991-12-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198906001-00005
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pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:Investigative radiology
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journal_title:Investigative radiology
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journal_title:Investigative radiology
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journal_title:Investigative radiology
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doi:10.1097/00004424-199403000-00015
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199805000-00008
更新日期:1998-05-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31822311a9
更新日期:2011-11-01 00:00:00
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journal_title:Investigative radiology
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doi:10.1097/RLI.0000000000000429
更新日期:2018-04-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e318243e062
更新日期:2012-05-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章,评审
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更新日期:2018-10-01 00:00:00