scholarly journals Pre-operative Percutaneous Nephrolithotripsy Characterisation of Kidney Stones with Second-Generation Dual-Source Dual-Energy Computed Tomography

2020 ◽  
Vol 27 (5) ◽  
pp. 43-52
Author(s):  
DK Mella Mohd Ali ◽  
Mohd Hafizi Mahmud ◽  
Noor Shafini Mohamad

Background: The current clinical practice to manage kidney stone requires knowledge of the stone composition. However, it is often difficult to determine the actual stone composition before a stone is operatively removed from the patient. Dual-energy computed tomography (DECT) can predict urinary stone composition, but it is not widely adopted. The purpose of the study was to investigate the use of a second-generation DECT with tin or stannum (Sn) filter for characterising the kidney stones composition. Methods: Thirty-three kidney stones were scanned ex vivo using a dual-source (DS)DECT scanner with dual-energy (DE) mode of 80/140 kVp with and without 4 mm Sn filtration. DE ratio was calculated to determine the kidney stones composition (uric acid, calcium oxalate, calcium phosphate and cystine). The median DE ratio of the stones was compared using Wilcoxon signed rank test and the results were further correlated with semi-quantitative Fourier transform infrared (FTIR) spectroscopy analysis using Kendall’s Tau test with P < 0.05 deemed to be statistically significant. Results: Second-generation DS-DECT could significantly discriminate the stones composition with and without Sn filtration (P < 0.001). The median DE ratio of uric acid, calcium oxalate and cystine stones were significantly higher with Sn filtration than those without filtration (P < 0.05). DECT results revealed significant correlation with FTIR spectroscopy analysis (r = 0.716, P < 0.001). DECT with Sn filtration showed increased performance (100% sensitivity, 0% specificity) than those without filtration (48.5% sensitivity, 0% specificity) in the detection of the kidney stone subtypes. Conclusion: In the second-generation DECT with additional Sn filtration, DECT has shown a significant performance in characterising and discriminating the kidney stone composition. This may improve diagnostic and therapy management in kidney stones cases.

2013 ◽  
Vol 20 (1) ◽  
Author(s):  
Aries Alpendri ◽  
Danarto HR

Objective: The purpose of this study was to know the bacterial and sensitivity pattern towards antimicrobials on kidney stones and to know the stone composition of kidney stones. Material &Method: Data were collected from medical record in 1 year period from January until Desember 2008 with descriptive study design. Results: We found 59 patients in that period, 32 males and 27 females, the mean age was 52,5 ± 10,31 with age 31 – 75 years old, most patients came from Bantul (16,9%) and 25,4% patients were housewives. From urine analysis we found leucocyturia (44,1%), erythrocyturia (39,0%), nitrituria (3,4%) and bacteriuria (6,8%). Urine culture showed E. coli (12,5%) and Candida (12,5%) being the most common causative microorganism. No antimicrobials was sensitive to all bacteriae while all antifungal was sensitive to candida. Stone composition showed ammonium (98%), calcium oxalate (91,8%), calcium non oxalate (93,9%), carbonate (22,4%), cholesterol (14,3%), uric acid (10,2%) and phosphate acid (10,2%). Conclusion: The most common stone composition were ammonium, calcium oxalate, and calcium non oxalate. E. coli still being the most common causative microorganism.Keywords: Kidney stone, stone composition, urinary tract infection, urine analysis, urine culture.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Tamara Cunha ◽  
Adrian Rodriguez ◽  
Pietro Manuel Ferraro

Abstract Background and Aims Urinary supersaturation (SS) contributes to stone formation, and its assessment in stone formers may be helpful in clinical practice. Several computer programs are available for SS calculation, including EQUIL2, JESS and Lithorisk1. The aim of this study was to evaluate changes in SS in 24-hour urine in patients with known stone composition before and after about three months of regular treatment. Method Patients who submitted their stone/s for composition analysis and had provided an adequate 24-hour urine collection (creatinine 15-20 mg/kg/24-hour) before and around 90 days under regular treatment were included. Stone composition was defined using morphoconstitutional and infrared spectroscopy. The treatment was initiated in accordance with specific guidelines, and included dietary advices and medications2. SS for calcium oxalate (CaOx), calcium phosphate (CaP) and uric acid (UA) using EQUIL2, JESS and Lithorisk were calculated at baseline and after about 90 days on treatment. Continuous variables were reported as means (SD) while categorical variables were reported as frequencies and percentages. Baseline and follow-up SS urine values were compared using the Wilcoxon signed-rank test. 3D graphs were plotted using mean SS values of CaOx, CaP and UA obtained from each program before and after treatment, dividing the stones into 4 groups1: calcium oxalate monohydrate (COM), calcium oxalate dihydrate (COD), calcium phosphate (CaP), and uric acid (UA). Ethical Committee approval was obtained. Results 105 patients (61 men, 58%) were followed and provided 24h urine collection. Of these, 101 (96%) were recurrent patients. The mean (SD) follow-up was 94 (14) days. 48 (46%) of all calculi were made of CaOx, either COM or COD, 36 (34%) of UA, and 21 (20%) of CaP. A significant reduction in SS values during treatment was observed in patients with COM (p&lt;0.05) , COD (p&lt;0.001), and UA stones (p&lt;0.001) with all programs. The reduction in SS values over time in patients with CaP stones was not significant (Table 1). Figure 1 shows 3D plots with SS before and after treatment into 4 groups of stone formers. Conclusion EQUIL2, JESS and Lithorisk are suitable software currently used for clinical and research purposes. SS values calculated by EQUIL2, JESS and Lithorisk during follow-up showed a significant reduction among COM, COD and UA stone formers. CaP stone formers did not show significant changes in SS over time.


2016 ◽  
Vol 58 (2) ◽  
pp. 120-128 ◽  
Author(s):  
R. Salvador ◽  
M.P. Luque ◽  
A. Ciudin ◽  
B. Paño ◽  
L. Buñesch ◽  
...  

2017 ◽  
Vol 3 (1) ◽  
pp. 11
Author(s):  
Baidyanath Yadav ◽  
Surendra Maharjan

Introduction. Dual Energy Computed Tomography (DECT) scan can provides simple and reliable differentiation between uric acid and non-uric acid stones. The characterization of various stones was based on the dual energy ratio and x-ray attenuation or HU. Methodology. A prospective study was conducted among 101 adult patients in Tribhuvan University Teaching Hospital (TUTH), Nepal. Informed written consent was obtained from all the participants. The standard low doses CT KUB were performed in multi-slice CT scanner (Siemens Somatom Definition AS+ 128 slice) at 120 kVp and 250 mAs. When stones were detected, second dual energy scans using 80 kVp and 140 kVp were obtained focusing only on the region of stones for their characterization. After post processing and graphical analysis at Syngo Via work station, the components of the stones were identified. Statistical analysis was performed in SPSS v21.0 software.Results. Out of 101 patients, 49 (48.5%) had calcium oxalate stones, 17 (16.87%) had uric acid stones, 16 (15.8%) had hydroxyapatite, 15 (14.9%) had cystine and 4 (4%) had mixed type of stones. Dual energy ratios were ranged from 0.55-1.11 for uric acid stone, 1.12-1.24 for cystine and more than 1.24 for calcium oxalate and hydroxyapatite stones. The mean HU noted in our study were; for uric acid stones (461.12 ± 119 HU at 80 kV, 449 ± 98.5 HU at 140 kV), for cystine (870.79 ± 386 at 80 kV, 743 ± 341 at 140 kV), for calcium oxalate (1246 ± 448 at 80 kV, 915 ± 316 at 140 kV) for hydroxyapatite (1301 ± 387 at 80 kV, 896 ± 315 at 140 kV) and mixed stone had (779.25 ± 269 HU at 80 kV, 665.5 ± 252 HU at 140 kV).


2013 ◽  
Vol 48 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Carlo Nicola De Cecco ◽  
Anna Darnell ◽  
Napoleón Macías ◽  
Juan Ramón Ayuso ◽  
Sonia Rodríguez ◽  
...  

2021 ◽  
pp. 20210084
Author(s):  
Elisabeth Appel ◽  
Christoph Thomas ◽  
Andrea Steuwe ◽  
Benedikt M Schaarschmidt ◽  
Olga R Brook ◽  
...  

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.


2020 ◽  
Vol 7 (10) ◽  
pp. 233-237
Author(s):  
Maha Esmeal Ahmed ◽  
Mwahib Sid Ahmed Aldosh

Objective: The aim of study was to study the chemical composition of renal stone in Sudanese population using computed tomography scan. Method: This is analytic study conducted in Khartoum state hospitals in the period from November 2018 to October 2019.The problem of the study was no similar study done in Sudanese populations. The study was done in 100 patients. The data was collected from computed tomography scan to the kidneys, ureters and urinary bladder. Classified and analyzed by   statistical package for the social sciences application (SPSS). Results: The study found that most chemical composition of renal stone among Sudanese population was uric acid (0%), Cystine (26%) then Struvite (14%) and calcium (60%). The most effective age group with renal stone was (61-70) years old (36.7%) and same age group have a Struvite stone (28.3%). Furthermore, the most common age group with a cyctine renal stone were the cystine affect in the age between 50 years to 60 years old. The uric acid, Cystine, and calcium stone composition may be reliably predicted in vivo on the basis of dual-energy Computed tomography findings. In the future, a single dual-energy computed tomography examination may contribute to not only the identification but also the chemical characterization of stones in the urinary tract and it may add to the information available from non-enhanced conventional CT performed for evaluation of nephrolithiasis.


2021 ◽  
Vol 18 (3) ◽  
Author(s):  
Xianghu Meng ◽  
Xueying Sun ◽  
Rong Cong ◽  
Liang Qi ◽  
Zengjun Wang ◽  
...  

Background: Most previous studies have demonstrated the possibility of using dual-source dual-energy computed tomography (DSDECT) to distinguish pure stones with high accuracy. While stones are usually composed of a mixture of substances, very few studies have focused on these stone compositions. Objectives: To retrospectively evaluate the diagnostic accuracy of DSDECT in predicting the composition of mixed urinary calculi in vivo compared to the postoperative infrared spectroscopy (IRS) for stone analysis. Materials and Methods: We retrospectively included 111 patients with 117 mixed urinary stones, detected by IRS, who underwent DSDECT between June 2018 and March 2020. Patients diagnosed with urolithiasis were examined by DSDECT preoperatively. The final stone composition was detected by IRS in vitro postoperatively. Also, the stone composition predicted by DSDECT was compared to the IRS results, known as the reference standard. Results: According to the results of IRS, 117 mixed urinary calculi, composed of a main constituent and minor admixtures, were divided into four groups: calcium oxalate (CaOx)-hydroxyapatite (HA) (n = 70); HA-CaOx (n = 36); uric acid (UA)-CaOx (n = 8); and cystine (CYS)-HA (n = 3). The accuracy of DSDECT in predicting different components of mixed urinary stones was 68.4%, 64.1%, 97.4%, and 97.5% for the CaOx-HA, HA-CaOx, UA-CaOx, and CYS-HA stones, respectively. The imaging characteristics of different mixed urinary stones, as shown by DSDECT, revealed that the CaOx-HA ratio value was lower than that of HA-CaOx (1.59 ± 0.11 vs. 1.66 ± 0.22; P < 0.05). Meanwhile, the computed tomography (CT) values of CaOx-HA under 150 kV were higher than those of HA-CaOx (915.41 ± 226.84 vs .799.56 ± 252.01; P < 0.05). Conclusion: Although DSDECT has a relatively low accuracy for predicting the components of CaOx-HA and HA-CaOx in vivo, its combination with the measured ratio and CT values may help differentiate these stones.


2021 ◽  
Vol 28 (3) ◽  
pp. E202134
Author(s):  
Shafqat Shabir Bhawani ◽  
Majid Jehangir ◽  
Mohammad Masood ◽  
Sajjad Ahmad Dar ◽  
Sajad Nazir Syed

Introduction. Computed tomography is more accurate than excretory urography in evaluation of renal stones due to its high sensitivity and temporal resolution; it permits sub-millimetric evaluation of the size and site of calculi but cannot evaluate their chemical composition. Dual-energy computed tomography allows evaluating the chemical composition of urinary calculi using simultaneous image acquisition at two different energy levels. The objective of the research was to determine renal stone composition using dual-energy multidetector computed tomography, and its correlation with post-extraction chemical analysis of stones. Materials and Methods. This prospective study was conducted in the Department of Radiodiagnosis and Imaging from September 2017 to March 2019. A total of 50 patients with urolithiasis at the age of 18-70 years were included in the study. Dual-energy computed tomography ratios of various stones were noted, and preoperative composition of calculi was given based on their colour and dual-energy computed tomography ratio. These results were compared with the post-extraction chemical analysis of stones (using Fourier infrared transform spectroscopy as the standard comparative method.) Results. The most common type of calculi in our study population was calcium oxalate stones (78%) followed by uric acid stones (12%), cystine stones (6%) and hydroxyapatite stones (4%). The dual-energy ratio of calcium oxalate, uric acid, cystine and hydroxyapatite stones ranged from 1.38-1.59, 0.94-1.08, and 1.20-1.28 and 1.52-1.57, respectively, with the mean dual-energy ratio of 1.43, 1.01, 1.25 and 1.55, respectively. Dual-energy computed tomography was found to be 100% sensitive and specific for differentiating uric acid stones from non‑uric acid stones. The sensitivity and specificity in differentiating calcium oxalate calculus from non‑calcium oxalate calculus was 97.5% and 90.9%, respectively, with 96% accuracy and kappa value of 0.883 suggesting strong agreement. Conclusions. Dual-energy computed tomography is highly sensitive and accurate in distinguishing between various types of renal calculi. It has vital role in management as uric acid calculi are amenable to drug treatment, while most of non-uric acid calculi require surgical intervention.


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