Dataset Information

Quantitative Prediction of Stone Fragility From Routine Dual Energy CT: Ex vivo proof of Feasibility.

ABSTRACT:

Rationale and objectives

Previous studies have demonstrated a qualitative relationship between stone fragility and internal stone morphology. The goal of this study was to quantify morphologic features from dual-energy computed tomography (CT) images and assess their relationship to stone fragility.

Materials and methods

Thirty-three calcified urinary stones were scanned with micro-CT. Next, they were placed within torso-shaped water phantoms and scanned with the dual-energy CT stone composition protocol in routine use at our institution. Mixed low- and high-energy images were used to measure volume, surface roughness, and 12 metrics describing internal morphology for each stone. The ratios of low- to high-energy CT numbers were also measured. Subsequent to imaging, stone fragility was measured by disintegrating each stone in a controlled ex vivo experiment using an ultrasonic lithotripter and recording the time to comminution. A multivariable linear regression model was developed to predict time to comminution.

Results

The average stone volume was 300 mm³ (range: 134-674 mm³). The average comminution time measured ex vivo was 32 seconds (range: 7-115 seconds). Stone volume, dual-energy CT number ratio, and surface roughness were found to have the best combined predictive ability to estimate comminution time (adjusted R² = 0.58). The predictive ability of mixed dual-energy CT images, without use of the dual-energy CT number ratio, to estimate comminution time was slightly inferior, with an adjusted R² of 0.54.

Conclusions

Dual-energy CT number ratios, volume, and morphologic metrics may provide a method for predicting stone fragility, as measured by time to comminution from ultrasonic lithotripsy.

SUBMITTER: Ferrero A

PROVIDER: S-EPMC5111401 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Publications

Quantitative Prediction of Stone Fragility From Routine Dual Energy CT: Ex vivo proof of Feasibility.

Ferrero Andrea A Montoya Juan C JC Vaughan Lisa E LE Huang Alice E AE McKeag Ian O IO Enders Felicity T FT Williams James C JC McCollough Cynthia H CH

Academic radiology 20161004 12

<h4>Rationale and objectives</h4>Previous studies have demonstrated a qualitative relationship between stone fragility and internal stone morphology. The goal of this study was to quantify morphologic features from dual-energy computed tomography (CT) images and assess their relationship to stone fragility.<h4>Materials and methods</h4>Thirty-three calcified urinary stones were scanned with micro-CT. Next, they were placed within torso-shaped water phantoms and scanned with the dual-energy CT st ...[more]

PMID: 27717761

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Dataset Information

Quantitative Prediction of Stone Fragility From Routine Dual Energy CT: Ex vivo proof of Feasibility.

Rationale and objectives

Materials and methods

Results

Conclusions

Publications

Quantitative Prediction of Stone Fragility From Routine Dual Energy CT: Ex vivo proof of Feasibility.

Similar Datasets

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