Evaluation of split-filter dual-energy CT for characterization of urinary stones

2021 ◽  
pp. 20210084
Author(s):  
Elisabeth Appel ◽  
Christoph Thomas ◽  
Andrea Steuwe ◽  
Benedikt M Schaarschmidt ◽  
Olga R Brook ◽  
...  
Keyword(s):  
Uric Acid ◽  
Urinary Stone ◽  
Dual Energy ◽  
Urinary Stones ◽  
Dual Energy Ct ◽  
Ct Scanner ◽  
Stone Composition ◽  
Calcium Stones ◽  
Uric Acid Stones ◽  
Dual Source

Objective: To assess accuracy of dual-energy computed tomography (DECT) to differentiate uric acid from calcium urinary stones in dual-energy split filter vs sequential-spiral vs dual-source acquisition. Methods: Thirty-four urinary stones (volume 89.0 ± 77.4 mm³; 17 calcium stones, 17 uric acid stones) were scanned in a water-filled phantom using a split-filter equipped CT scanner (SOMATOM Definition Edge, Siemens Healthineers, Forchheim, Germany) in split-filter mode at 120kVp and sequential-spiral mode at 80 and 140kVp. Additional DE scans were acquired at 80 and 140kVp (tin filter) with a dual-source CT scanner (SOMATOM Definition FLASH, Siemens Healthineers). Scans were performed with a CTDIvol of 7.3mGy in all protocols. Urinary stone categorization was based on dual energy ratio (DER) using an automated 3D segmentation. As reference standard, infrared spectroscopy was used to determine urinary stone composition. Results: All three DECT techniques significantly differentiated between uric acid and calcium stones by attenuation values and DERs (p < 0.001 for all). Split-filter DECT provided higher DERs for uric acid stones, when compared with dual-source and sequential-spiral DECT, and lower DERs for calcified stones when compared with dual-source DECT (p < 0.001 for both), leading to a decreased accuracy for material differentiation. Conclusion: Split-filter DECT, sequential-spiral DECT and dual-source DECT all allow for the acquisition of DER to classify urinary stones. Advances in knowledge: Split-filter DECT enables the differentiation between uric acid and calcium stones despite decreased spectral separation when compared with dual-source and dual-spiral DECT.

scholarly journals Single-energy CT predicts uric acid stones with accuracy comparable to dual-energy CT—prospective validation of a quantitative method

2021 ◽  
Author(s):  
Johan Jendeberg ◽  
Per Thunberg ◽  
Marcin Popiolek ◽  
Mats Lidén
Keyword(s):  
Uric Acid ◽  
Ct Scan ◽  
Prediction Models ◽  
Urinary Stone ◽  
Dual Energy ◽  
Urinary Stones ◽  
Dual Energy Ct ◽  
K Nearest Neighbors ◽  
Uric Acid Stones

Abstract Objectives To prospectively validate three quantitative single-energy CT (SE-CT) methods for classifying uric acid (UA) and non-uric acid (non-UA) stones. Methods Between September 2018 and September 2019, 116 study participants were prospectively included in the study if they had at least one 3–20-mm urinary stone on an initial urinary tract SE-CT scan. An additional dual-energy CT (DE-CT) scan was performed, limited to the stone of interest. Additionally, to include a sufficient number of UA stones, eight participants with confirmed UA stone on DE-CT were retrospectively included. The SE-CT stone features used in the prediction models were (1) maximum attenuation (maxHU) and (2) the peak point Laplacian (ppLapl) calculated at the position in the stone with maxHU. Two prediction models were previously published methods (ppLapl-maxHU and maxHU) and the third was derived from the previous results based on the k-nearest neighbors (kNN) algorithm (kNN-ppLapl-maxHU). The three methods were evaluated on this new independent stone dataset. The reference standard was the CT vendor’s DE-CT application for kidney stones. Results Altogether 124 participants (59 ± 14 years, 91 men) with 106 non-UA and 37 UA stones were evaluated. For classification of UA and non-UA stones, the sensitivity, specificity, and accuracy were 100% (37/37), 97% (103/106), and 98% (140/143), respectively, for kNN-ppLapl-maxHU; 95% (35/37), 98% (104/106), and 97% (139/143) for ppLapl-maxHU; and 92% (34/37), 94% (100/106), and 94% (134/143) for maxHU. Conclusion A quantitative SE-CT method (kNN-ppLapl-maxHU) can classify UA stones with accuracy comparable to DE-CT. Key Points • Single-energy CT is the first-line diagnostic tool for suspected renal colic. • A single-energy CT method based on the internal urinary stone attenuation distribution can classify urinary stones into uric acid and non-uric acid stones with high accuracy. • This immensely increases the availability of in vivo stone analysis.

scholarly journals Characterization of Urinary Stone Composition by Use of Third-Generation Dual-Source Dual-Energy CT With Increased Spectral Separation

2015 ◽  
Vol 205 (6) ◽  
pp. 1203-1207 ◽  
Author(s):  
Xinhui Duan ◽  
Zhoubo Li ◽  
Lifeng Yu ◽  
Shuai Leng ◽  
Ahmed F. Halaweish ◽  
...  
Keyword(s):  
Urinary Stone ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Third Generation ◽  
Stone Composition ◽  
Spectral Separation ◽  
Dual Source

scholarly journals Kidney Stone Composition in Various Country Around the World

2021 ◽  
Author(s):  
Adam Halinski ◽  
Elenko Popov ◽  
Kamran Hassan Bhattikam ◽  
Luca Boeri ◽  
Jonathan Cloutier ◽  
...  
Keyword(s):  
Uric Acid ◽  
Calcium Phosphate ◽  
Calcium Oxalate ◽  
Urinary Stones ◽  
Stone Composition ◽  
Calcium Stones ◽  
Uric Acid Stones ◽  
The World ◽  
Cystine Stones ◽  
Struvite Stones

Abstract To compare urinary stone composition patterns in different populations around the world in relation to the structure of their population, dietary habits, and climate. 1204 adult patients with urolithiasis and stone analysis was included . International websites were searched to obtain data. We observed 710(59%) patients with calcium oxalate, 31(1%) calcium phosphate, 161(13%) mixed calcium oxalate/calcium phosphate, 15(1%) carbapatite, 110(9%) uric acid, 7(<1%) urate, 100(9%) mixed uric acid/ calcium oxalate, 56(5%) struvite and 14(1%) cystine stones. Calcium stones were the most common in all countries (up to 91%) with the highest rates in Canada and China. Oxalate stones were more common than phosphate or mixed phosphate/oxalate stones except Egypt and India. The rate of uric acid stones, being higher in Egypt, India, Pakistan, Iraq, Poland, and Bulgaria. Struvite stones occurred in less than 5% except India (23%) and Pakistan (16%). Cystine stones occurred in 1%. The frequency of different types of urinary stones varies from country to country. Calcium stones are prevalent in all countries. Uric acid stones seems to depend mainly on climatic factors, being higher in countries with desert or tropical climates. Dietary patterns can also lead to an increase it. Struvite stones are decreasing in most countries.

Prospective prediction of the major component of urinary stone composition with dual-source dual-energy CT in vivo

2016 ◽  
Vol 71 (11) ◽  
pp. 1178-1183 ◽  
Author(s):  
G.-M.-Y. Zhang ◽  
H. Sun ◽  
H.-D. Xue ◽  
H. Xiao ◽  
X.-B. Zhang ◽  
...  
Keyword(s):  
Urinary Stone ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Stone Composition ◽  
Dual Source

Dual Energy Computed Tomography (DECT) for Determination of Renal Calculi Composition - In-Vivo Analysis and In-Vitro Comparison with Qualitative Chemical Analysis - A Prospective Comparative Study at a Single Centre at SDM Medical College and Hospital – Dharwad, Karnataka

2021 ◽  
Vol 8 (41) ◽  
pp. 3534-3540
Author(s):  
Srinivas Kalabhavi ◽  
Pramod Makannavar ◽  
Revanasiddappa Kanagali ◽  
Prabhath A.N. ◽  
Narendrakumar Shah
Keyword(s):  
Uric Acid ◽  
Chemical Analysis ◽  
Renal Stones ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Stone Composition ◽  
Uric Acid Stones ◽  
In Vivo Analysis

BACKGROUND Dual energy computed tomography (DECT) is a new method of computed tomography (CT) imaging which allows to determine stone composition in addition to assessing stone morphology. The purpose of this study was to evaluate the role of dual energy CT (DECT) preoperatively to assess the composition of urinary stones and to compare it with post-operative in vitro qualitative chemical analysis as reference standard. METHODS Forty patients (18 male and 22 female) who presented with symptoms of renal stones in the department of urology were included in the study. All 40 patients who were diagnosed to have renal stones clinically and by ultrasonography (USG) kidney, ureter and bladder (KUB) region were subjected to dual energy CT. The stone composition assessed in vivo using DECT preoperatively and in vitro by chemical analysis post operatively after stone extraction by surgical procedure. The results were compared by statistical analysis. Sensitivity, specificity and positive predictive value (PPV) were calculated and descriptive study done using Statistical Package for Social Sciences (SPSS) 20.00 version. Data was analysed by comparing it with correlative qualitative chemical analysis. RESULTS In our study, in vivo analysis using DECT showed most common type of stone was calcium oxalate seen in 20 cases compromising 50 % of total cases. Next common stone type was uric acid stone (22.5 %) followed by cysteine (17.5 %) and calcium hydroxyapatite (10 %) respectively. When the same stones were subjected to ex vivo chemical analysis, one of the calcium oxalate stone came out to be calcium phosphate and one of the cysteine stone came out to be mixed stone. Thus, out of 40 stones, 38 stones were found to have the same result in ex vivo chemical analysis as that of in vivo analysis by dual energy CT. Hence, accuracy of dual energy CT in diagnosis of renal stones was found to be 100 % with CI 91.19 % - 100 %. CONCLUSIONS With dual energy CT, it is possible to determine the composition of renal calculi in vivo non-invasively (with specificity of 100 % in our present study). Therefore, this helps in deciding the modality of treatment pre-operatively whether the stone is amenable to medical management (e.g., Uric acid stones) or requires extracorporeal shock wave lithotripsy (ESWL) or surgical intervention can be determined preoperatively. This helps to reduce the unnecessary financial burden and is found to be time saving. KEYWORDS Renal Calculus, Dual Energy CT, Stone Composition, Uric Acid Stones, Non-Uric Acid Stones, Attenuation, Hounsfield Units HU, Chemical Analysis of Stones.

scholarly journals In vivo identification of uric acid stones with dual-energy CT: diagnostic performance evaluation in patients

2009 ◽  
Vol 35 (5) ◽  
pp. 629-635 ◽  
Author(s):  
Paul Stolzmann ◽  
Marko Kozomara ◽  
Natalie Chuck ◽  
Michael Müntener ◽  
Sebastian Leschka ◽  
...  
Keyword(s):  
Uric Acid ◽  
Performance Evaluation ◽  
Diagnostic Performance ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Uric Acid Stones

scholarly journals Spectrum of pediatric urinary stone composition in North Western India: analysis at tertiary care center

2019 ◽  
Vol 7 (11) ◽  
pp. 4102
Author(s):  
Rama Kishan Saran ◽  
Pawan Katti ◽  
Kiran Mirdha ◽  
Sanya Saran ◽  
Rajendra Prasad Takhar
Keyword(s):  
Uric Acid ◽  
Calcium Phosphate ◽  
Calcium Oxalate ◽  
Pediatric Patients ◽  
Dietary Habits ◽  
Urinary Stone ◽  
Urinary Stones ◽  
Stone Composition ◽  
Epidemiological Characteristics ◽  
North Western

Background: Pediatric urolithiasis results in significant morbidity in later life. Incidence as well as site and chemical composition of calculi varies according to the changes in socio-economic conditions over time and the subsequent changes in dietary habits leading to a marked variation in the spectrum of urinary stone composition. To evaluate the spectrum of urinary stone composition in pediatric population from North-western India.Methods: This was a prospective observational study conducted between October 2013 and February 2019 which included pediatric patients with urolithiasis. Demographic and epidemiological characteristics including age, sex, geography, religion, socio-economic status, dietary habits were recorded. The location and sizes of stones were documented. The data was collected, analyzed and presented using summary statistics.Results: A total of 163 patients with urolithiasis were enrolled, of which 86 (53%) aged between 6 and 10 years, 49 (30%) aged between 11 and 14 years and 28 (17%) were aged between 0 and 5 years. The majority of patients were male (n=134; 82.21%). The most common location of the stone was urinary bladder (n=106; 65.03%) followed by kidney (n=33; 20.25%), urethra (n=16; 9.82%) and ureter (n=8; 4.91%). The upper tract (kidney and ureter) to the lower tract (bladder and urethra) stone ratio was 1:4. Stones with mixed composition were more than pure stones (73.62% versus 26.38%). The most common composition was the mixed stone of calcium oxalate, calcium phosphate and uric acid (n=36; 22.09%) followed by mixed stone of calcium oxalate monohydrate and dihydrate with uric acid (n=29; 17.79%), calcium oxalate and uric acid (n=25, 15.34%), calcium oxalate and calcium phosphate (n=20; 12.27%). Calcium oxalate was present in 80% of the stones, followed by uric acid in 7%, struvite in 6%, cystine in 3% and calcium phosphate in 2%.Conclusions: These results suggest that the prevalence of mixed stones with calcium oxalate as the predominant chemical component in the urinary stones of pediatric patients studied.

scholarly journals Time Changes in the Spectrum of Urinary Stone Composition: A Role for Climate Variations?

2020 ◽  
Author(s):  
Alberto Trinchieri ◽  
Alessandro Maletta ◽  
Giovanni Simonelli ◽  
Luca Boeri ◽  
Elisa De Lorenzis ◽  
...  
Keyword(s):  
Uric Acid ◽  
Calcium Oxalate ◽  
Calcium Oxalate Monohydrate ◽  
Urinary Stone ◽  
Northern Italy ◽  
Urinary Stones ◽  
Temperate Climate ◽  
Stone Composition ◽  
Statistical Institute ◽  
Time Changes

Abstract Introduction: An increase of the frequency of uric acid urinary stones compared to calcium-containing ones has been recently described. This study was aimed at assessing the frequency of different types of urinary stones in the population of northern Italy in the period 2016-18 compared to 2001-2003. Materials and Methods: Analyses by infrared spectroscopy of 1007 stones endoscopically removed at two institutions in the area of Milan (Northern Italy) were retrospectively considered. Stones were classified as calcium oxalate monohydrate (COM) and dihydrate (COD), mixed uric acid/calcium oxalate (UC); uric acid (UA), struvite (ST); apatite (CAP); mixed calcium oxalate / apatite (CAPOX); others. The patients were divided into two groups: 2001-2003 and 2016-2018. The average temperature values of the region over the two time periods were obtained by the national statistical institute. Results: The average age of the 2001-2003 group (45.8+/-15.4 years) was significantly lower than the average age of the 2016-18 group (57.9+/-14.8) (0.000). M / F ratio was similar in the two groups: 119 / 69 (1:0.58) in 2001-2003 MI and 527 / 292 (1:0.55) in 2016-18 (p = 0.862). COM stones tended to more frequent in 2016-18 group than in 2001-03. COD stones were significantly more frequent in 2001-03 than in 2016-18. ST stone frequency was increased from 2001-03 to 2016-18. No increase of uric acid containing stones was observed in 2016-18. Results were confirmed after adjustment by age. Averages annual regional temperatures increased from 14° C to 15.4° C during the two observation periods. Conclusions: No increase of UA stones was observed, probably due to the limited impact of the global warming in our temperate climate.

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