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Chen HW, Lee JT, Wei PS, Chen YC, Wu JY, Lin CI, Chou YH, Juan YS, Wu WJ, Kao CY. Machine learning models for screening clinically significant nephrolithiasis in overweight and obese populations. World J Urol 2024; 42:128. [PMID: 38460023 DOI: 10.1007/s00345-024-04826-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 01/16/2024] [Indexed: 03/11/2024] Open
Abstract
PURPOSES Our aim is to build and evaluate models to screen for clinically significant nephrolithiasis in overweight and obesity populations using machine learning (ML) methodologies and simple health checkup clinical and urine parameters easily obtained in clinics. METHODS We developed ML models to screen for clinically significant nephrolithiasis (kidney stone > 2 mm) in overweight and obese populations (body mass index, BMI ≥ 25 kg/m2) using gender, age, BMI, gout, diabetes mellitus, estimated glomerular filtration rate, bacteriuria, urine pH, urine red blood cell counts, and urine specific gravity. The data were collected from hospitals in Kaohsiung, Taiwan between 2012 and 2021. RESULTS Of the 2928 subjects we enrolled, 1148 (39.21%) had clinically significant nephrolithiasis and 1780 (60.79%) did not. The testing dataset consisted of data collected from 574 subjects, 235 (40.94%) with clinically significant nephrolithiasis and 339 (59.06%) without. One model had a testing area under curve of 0.965 (95% CI, 0.9506-0.9794), a sensitivity of 0.860 (95% CI, 0.8152-0.9040), a specificity of 0.947 (95% CI, 0.9230-0.9708), a positive predictive value of 0.918 (95% CI, 0.8820-0.9544), and negative predictive value of 0.907 (95% CI, 0.8756-0.9371). CONCLUSION This ML-based model was found able to effectively distinguish the overweight and obese subjects with clinically significant nephrolithiasis from those without. We believe that such a model can serve as an easily accessible and reliable screening tool for nephrolithiasis in overweight and obesity populations and make possible early intervention such as lifestyle modifications and medication for prevention stone complications.
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Affiliation(s)
- Hao-Wei Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Jung-Ting Lee
- School of Medicine, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Pei-Siou Wei
- Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Yu-Chen Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Jeng-Yih Wu
- Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Department of Health Management Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Faculty of College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chia-I Lin
- Health Management Center, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan
| | - Yii-Her Chou
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yung-Shun Juan
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Wen-Jeng Wu
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung, Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chung-Yao Kao
- Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan.
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Kandasamy M, Chan M, Xiang H, Chan L, Ridley L. Comparison of diagnostic accuracy of ultra low-dose computed tomography and X-ray of the kidneys, ureters and bladder for urolithiasis in the follow-up setting. J Med Imaging Radiat Oncol 2023. [PMID: 37997533 DOI: 10.1111/1754-9485.13605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 11/03/2023] [Indexed: 11/25/2023]
Abstract
INTRODUCTION Urolithiasis is frequently followed up with a low-dose computed tomography of the kidneys ureters and bladder (LD-CTKUB) with doses typically less than 3 millisieverts. Although X-ray is a lower dose (0.5-1.1 mSv) alternative for follow up, it has lower diagnostic accuracy and is limited to radiopaque calculi. This study aims to compare the diagnostic accuracy of sub-millisievert ultra-low dose CT (ULD-CTKUB) against X-ray KUB for the follow up of urolithiasis when both are compared against the standard of care of a low-dose CT KUB (LD-CTKUB). METHODS This prospective study included patients with a known diagnosis of urolithiasis on prior CTKUB presenting for follow up. Each patient underwent a repeat reference LD-CTKUB, ULD-CTKUB and X-ray KUB. All imaging studies were interpreted by three readers. The radiation dose and quantitative noise was calculated for each CT. Both CT and X-ray were assessed for the presence, number and size of all calculi ≥2 mm. RESULTS A total of 58 patients were included in this study. LD-CTKUB identified 197 calculi. ULD-CTKUB in our study had a mean effective dose of 0.5 mSv compared to X-ray KUB where doses range in the literature from 0.5 to 1.1 mSv. Per-patient pooled analysis for intrarenal calculi when comparing ULD-CTKUB versus X-ray KUB against a reference LD-CTKUB found a sensitivity of 90% versus 67% (P < 0.01) and specificity of 93% versus 98% (P = 0.18) respectively. For ureteric calculi, the sensitivity was 67% versus 33% (P < 0.01) and specificity 94% versus 94% (P = 1.00) respectively. Per-stone pooled analysis detection rate was 79% for ULD-CTKUB versus 48% for X-ray (P < 0.01) when each was compared to the reference LD-CTKUB. Interobserver agreement was high for intrarenal calculi and moderate for ureteric calculi. CONCLUSION Sub-millisievert ULD-CTKUB had lower doses and higher sensitivity than X-ray in patients requiring follow up of known urolithiasis.
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Affiliation(s)
- Mayooran Kandasamy
- Department of Radiology, Concord Repatriation General Hospital, Sydney, New South Wales, Australia
| | - Michael Chan
- Department of Radiology, Concord Repatriation General Hospital, Sydney, New South Wales, Australia
- University of Sydney, Sydney, New South Wales, Australia
| | - Hao Xiang
- Department of Radiology, Concord Repatriation General Hospital, Sydney, New South Wales, Australia
- University of New South Wales, Sydney, New South Wales, Australia
| | - Lewis Chan
- Department of Urology, Concord Repatriation General Hospital, Sydney, New South Wales, Australia
| | - Lloyd Ridley
- Department of Radiology, Concord Repatriation General Hospital, Sydney, New South Wales, Australia
- University of Sydney, Sydney, New South Wales, Australia
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Taghavi K, Kusel A, Webb N, McCahy P, Badawy M, Ditchfield M. The burden of radiation exposure in children requiring percutaneous nephrolithotomy. J Pediatr Urol 2023; 19:559.e1-559.e7. [PMID: 37302924 DOI: 10.1016/j.jpurol.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 06/13/2023]
Abstract
BACKGROUND Children undergoing investigation and management for complex upper tract urolithiasis often require multimodal imaging. The significance of related radiation exposure in stone care pathways has received little attention in the published literature. STUDY DESIGN Medical records of paediatric patients undergoing percutaneous nephrolithotomy were retrospectively analysed to ascertain the modalities used and determine extent of radiation exposure occurring during each care pathway. Radiation dose simulation and calculation was performed a priori. The cumulative effective dose (mSv) and cumulative organ dose (mGy) for radiosensitive organs was calculated. RESULTS A total of 140 imaging studies were included from the care pathways of 15 children with complex upper tract urolithiasis. Median follow-up was 9.6 years (range: 6.7-16.8 years). The average number of imaging studies with ionising radiation per patient was nine, with a cumulative effective dose of 18.3 mSv across all modalities. The most common modalities were: mobile fluoroscopy (43%), x-ray (24%), and computed tomography (18%). The cumulative effective dose per study type was greatest for CT (4.09 mSv), followed by fixed and mobile fluoroscopy (2.79 mSv and 1.82 mSv, respectively). CONCLUSION There is high general awareness of radiation exposure involved in CT scanning with resultant caution in employing this modality in paediatric patients. However, the significant radiation exposure relating to fluoroscopy (whether fixed or mobile) is less well documented in children. We recommend implementing steps to minimise radiation exposure by optimisation and avoidance of certain modalities where possible. Paediatrics urologists must employ strategies to minimise radiation exposure in children with urolithiasis, given the significant exposures encountered.
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Affiliation(s)
- Kiarash Taghavi
- Department of Paediatric Urology, Monash Children's Hospital, Monash Health, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia.
| | - Amanda Kusel
- Department of Paediatric Urology, Monash Children's Hospital, Monash Health, Melbourne, Australia
| | - Nathalie Webb
- Department of Paediatric Urology, Monash Children's Hospital, Monash Health, Melbourne, Australia; School of Clinical Sciences, Monash University, Melbourne, Australia
| | - Philip McCahy
- Department of Urology, Monash Health, Melbourne, Australia; School of Clinical Sciences, Monash University, Melbourne, Australia
| | - Mohamed Badawy
- Monash Health Imaging, Monash Health, Clayton, Victoria, Australia; Department of Medical Imaging and Radiation Sciences, School of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
| | - Michael Ditchfield
- Department of Paediatrics, Monash University, Melbourne, Australia; Monash Health Imaging, Monash Health, Clayton, Victoria, Australia
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Zhou Z, Zhou X, Zhang Y, Yang Y, Wang L, Wu Z. Butyric acid inhibits oxidative stress and inflammation injury in calcium oxalate nephrolithiasis by targeting CYP2C9. Food Chem Toxicol 2023:113925. [PMID: 37414240 DOI: 10.1016/j.fct.2023.113925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 06/20/2023] [Accepted: 06/29/2023] [Indexed: 07/08/2023]
Abstract
This study investigates the mechanism by which butyric acid can protect against calcium oxalate (CaOx) nephrolithiasis. To do so, a rat model was used with 0.75% ethylene glycol administration to induce CaOx crystal formation. Histological and von Kossa staining revealed calcium deposits and renal injury, while dihydroethidium fluorescence staining was used to detect reactive oxygen species (ROS) levels. Flow cytometry and TUNEL assays were used to assess apoptosis, respectively. Treatment with sodium butyrate (NaB) was found to partially reverse the oxidative stress, inflammation, and apoptosis associated with CaOx crystallization in the kidney. In addition, in HK-2 cells, NaB reversed the decreased cell viability, increased ROS levels and apoptosis damage caused by oxalate exposure. Network pharmacology was employed to predict the target genes of butyric acid, CYP2C9. Subsequently, NaB was found to significantly reduce CYP2C9 levels in vivo and in vitro, and inhibition of CYP2C9 by Sulfaphenazole (a specific CYP2C9 inhibitor), was able to reduce ROS levels, inflammation injury, and apoptosis in oxalate-induced HK-2 cells. Collectively, these findings suggest that butyric acid may inhibit oxidative stress and reduce inflammation injury in CaOx nephrolithiasis by suppressing CYP2C9.
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Affiliation(s)
- Zijian Zhou
- Department of Urology, Huashan Hospital & Institute of Urology, Fudan University, Shanghai, 200040, PR China; Clinical Research Center of Urolithiasis, Shanghai Medical College, Fudan University, Shanghai, 200040, PR China
| | - Xuan Zhou
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, PR China
| | - Yu Zhang
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai, 200040, PR China
| | - Yuanyuan Yang
- Department of Urology, Huashan Hospital & Institute of Urology, Fudan University, Shanghai, 200040, PR China; Clinical Research Center of Urolithiasis, Shanghai Medical College, Fudan University, Shanghai, 200040, PR China
| | - Lujia Wang
- Department of Urology, Huashan Hospital & Institute of Urology, Fudan University, Shanghai, 200040, PR China; Clinical Research Center of Urolithiasis, Shanghai Medical College, Fudan University, Shanghai, 200040, PR China.
| | - Zhong Wu
- Department of Urology, Huashan Hospital & Institute of Urology, Fudan University, Shanghai, 200040, PR China; Clinical Research Center of Urolithiasis, Shanghai Medical College, Fudan University, Shanghai, 200040, PR China.
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Hosier GW, Hakam N, Hamouche F, Cortez X, Charondo L, Yang H, Chan C, Chang K, Unno R, Sui W, Bayne DB, Stoller ML, Chi T. Ultrasound-Only Percutaneous Nephrolithotomy Is Safe and Effective Compared to Fluoroscopy-Directed Percutaneous Nephrolithotomy. J Endourol 2023; 37:634-641. [PMID: 37051696 PMCID: PMC10771882 DOI: 10.1089/end.2022.0761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023] Open
Abstract
Introduction: Outcomes after ultrasound-only percutaneous nephrolithotomy (PCNL), in which no fluoroscopy is used, are not well known. The goal of this study was to compare outcomes of ultrasound-only and fluoroscopy-directed PCNL. Materials and Methods: Prospectively collected data from the Registry for Stones of the Kidney and Ureter database were reviewed for all patients who underwent PCNL at one academic center from 2015 to 2021. Primary outcomes were complications and stone-free rates (no residual fragments ≥3 mm). Results: Of the 141 patients who underwent ultrasound-only PCNL and 147 who underwent fluoroscopy-directed PCNL, there was no difference in complication rates (15% vs 16%, p = 0.87) or stone-free status (71% vs 65%, p = 0.72), respectively. After adjusting for body mass index, American Society of Anesthesiologists (ASA), stone size, and stone complexity by Guy score, ultrasound-only PCNL was not associated with any increased odds of complications (odds ratio [OR] 0.7, 95% confidence interval [CI] 0.3-1.6, p = 0.41) or residual stone fragments ≥3 mm (OR 1.0, 95% CI 0.5-1.9, p = 0.972) compared with fluoroscopy-directed PCNL. Ultrasound-only PCNL was associated with shorter operative time (median 99.5 vs 126 minutes, p < 0.001), and the use of ultrasound remained a significant predictor of short operative time (<100 minutes) after controlling for supine positioning, stone size, and stone complexity by Guy score (OR 2.31, 95% CI 1.01-5.29, p = 0.048). Patients in the ultrasound-only group were spared a mean radiation exposure dose of 10 mGy per procedure. Conclusions: Ultrasound-only PCNL is safe and achieves similar stone-free rates compared with fluoroscopy-directed PCNL with the added benefit of avoidance of radiation.
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Affiliation(s)
- Gregory W. Hosier
- Section of Urology, Department of Surgery, University of Manitoba, Winnipeg, Canada
| | - Nizar Hakam
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Fadl Hamouche
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Xavier Cortez
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Leslie Charondo
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Heiko Yang
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Carter Chan
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Kevin Chang
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Rei Unno
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Wilson Sui
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - David B. Bayne
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Marshall L. Stoller
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
| | - Thomas Chi
- Department of Urology, University of California, San Francisco, San Francisco, California, USA
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Huettenbrink C, Hitzl W, Distler F, Ell J, Ammon J, Pahernik S. Personalized Prediction of Patient Radiation Exposure for Therapy of Urolithiasis: An Application and Comparison of Six Machine Learning Algorithms. J Pers Med 2023; 13:jpm13040643. [PMID: 37109029 PMCID: PMC10146849 DOI: 10.3390/jpm13040643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
The prediction of radiation exposure is an important tool for the choice of therapy modality and becomes, as a component of patient-informed consent, increasingly important for both surgeon and patient. The final goal is the implementation of a trained and tested machine learning model in a real-time computer system allowing the surgeon and patient to better assess patient's personal radiation risk. In summary, 995 patients with ureterorenoscopy over a period from May 2016 to December 2019 were included. According to the suggestions based on actual literature evidence, dose area product (DAP) was categorized into 'low doses' ≤ 2.8 Gy·cm2 and 'high doses' > 2.8 Gy·cm2 for ureterorenoscopy (URS). To forecast the level of radiation exposure during treatment, six different machine learning models were trained, and 10-fold crossvalidated and their model performances evaluated in training and independent test samples. The negative predictive value for low DAP during ureterorenoscopy was 94% (95% CI: 92-96%). Factors influencing the radiation exposure were: age (p = 0.0002), gender (p = 0.011), weight (p < 0.0001), stone size (p < 0.000001), surgeon experience (p = 0.039), number of stones (p = 0.0007), stone density (p = 0.023), use of flexible endoscope (p < 0.0001) and preoperative stone position (p < 0.00001). The machine learning algorithm identified a subgroup of patients of 81% of the total sample, for which highly accurate predictions (94%) were possible allowing the surgeon to assess patient's personal radiation risk. Patients without prediction (19%), the medical expert can make decisions as usual. Next step will be the implementation of the trained model in real-time computer systems for clinical decision processes in daily practice.
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Affiliation(s)
- Clemens Huettenbrink
- Department of Urology, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany
| | - Wolfgang Hitzl
- Team Biostatistics and Publication of Clinical, Research and Innovation Management (RIM), Trial Studies, Paracelsus Medical University, 5020 Salzburg, Austria
- Department of Ophthalmology and Optometry, Paracelsus Medical University Salzburg, 5020 Salzburg, Austria
- Research Program Experimental Ophthalmology and Glaucoma Research, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Florian Distler
- Department of Urology, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany
| | - Jascha Ell
- Department of Urology, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany
| | - Josefin Ammon
- Institute of Medical Physics, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany
| | - Sascha Pahernik
- Department of Urology, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany
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Bernardor J, Bidault V, Bacchetta J, Cabet S. Pediatric urolithiasis: what can pediatricians expect from radiologists? Pediatr Radiol 2023; 53:695-705. [PMID: 36329164 DOI: 10.1007/s00247-022-05541-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/03/2022] [Accepted: 10/14/2022] [Indexed: 11/06/2022]
Abstract
The incidence of urolithiasis in children has increased over the two last decades. Urolithiasis formation results from urine oversaturation following insufficient water intake, urinary obstruction (notably in cases of congenital uropathies), excess production of an insoluble compound, or imbalance between crystallization promoters and inhibitors. Whereas most urolithiases in adults occur secondary to environmental factors, in children, secondary causes are far more frequent, and 15% are related to genetic causes, most often monogenic. This is especially true in recurrent forms, with early and rapid progression and bilateral stones, and in cases of familial history or consanguinity. Because of differing clinical management, one should rule out cystinuria, primary hyperoxaluria and renal tubular acidosis, among other causes of urolithiasis. As such, a complete biochemical evaluation must be performed in all cases of pediatric urolithiasis, even in cases of an underlying uropathy. Ultrasound examination is the first-line modality for imaging pediatric urolithiasis, allowing both diagnosis (urolithiasis and its complications) and follow-up. US examination should also explore clues to an underlying cause of urolithiasis. This review is focused on the role of imaging in the management and etiological assessment of pediatric urolithiasis. Radiologists play an important role in pediatric urolithiasis, facilitating diagnosis, follow-up and surgical management. A trio of clinicians (pediatric nephrologist, pediatric surgeon, pediatric radiologist) is thus necessary in the care of these pediatric patients.
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Affiliation(s)
- Julie Bernardor
- Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares, Filières de Santé Maladies Rares OSCAR, ORKID et ERKNet, Service de Néphrologie Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France.
- Institut National de la Santé et de la Recherche Médicale, Lyon, France.
- Service de Néphrologie Pédiatrique, Centre Hospitalo-Universitaire de Nice, Hôpital Archet, Nice, France.
- Faculté de Médecine, Université Côte d'Azur, Nice, France.
| | - Valeska Bidault
- Service de Chirurgie Pédiatrique, Hôpital Bicêtre, Assistance Publique des Hôpitaux de Paris, Le Kremlin-Bicêtre, France
| | - Justine Bacchetta
- Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares, Filières de Santé Maladies Rares OSCAR, ORKID et ERKNet, Service de Néphrologie Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France
- Institut National de la Santé et de la Recherche Médicale, Lyon, France
- Faculté de Médecine Lyon Est, Université de Lyon, Lyon, France
| | - Sara Cabet
- Service d'imagerie Pédiatrique et Foetale, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France
- Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Physiopathologie et Génétique du Neurone et du Muscle, Institut NeuroMyoGène, Université de Lyon, Lyon, France
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Dreger NM, Stapelmann D, Rebacz P, Roth S, Brandt AS, von Rundstedt FC, Degener S. Hydrostatic pressure of the renal pelvis as a radiation-free alternative to fluoroscopic nephrostogram following percutaneous nephrolithotomy. BMC Urol 2023; 23:46. [PMID: 36978025 PMCID: PMC10052835 DOI: 10.1186/s12894-023-01225-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Abstract
Background
We evaluated the hydrostatic pressure of the renal pelvis (RPP) as a radiation-free alternative to fluoroscopic nephrostogram to assess ureteral patency after percutaneous nephrolithotomy (PCNL).
Methods
Retrospective non-inferiority study analyzing 248 PCNL-patients (86 female (35%) and 162 males (65%)) between 2007 and 2015. Postoperatively, RPP was measured using a central venous pressure manometer in cmH2O. The primary endpoint was to assess RPP depending on the patency of the ureter and the nephrostomy tube removal. Secondary, the upper limit of normal RPP of $$\le$$
≤
20 cmH2O was assessed as an indicator of an unobstructed patency.
Results
The median procedure duration was 141 min (112–171.5) with a stone free rate of 82% (n = 202). RPP was significantly higher in patients with obstructive nephrostogram with 25.0 mmH2O (21.0–32.0) versus 20.0 mmH2O (16.0–24.0; p < 0.001). The pressure was lower in successful nephrostomy removal with 18 cmH2O (15–21) versus 23 cmH2O (20–29) in the leakage group (p < 0.001). The analysis of a cut-off of $$\le$$
≤
20 cmH2O showed a sensitivity of 76.9% (95% CI [60.7%; 88.9%]) and a specificity of 61.5% (95% CI [54.6%; 68.2%]). The negative predictive value was 93.4% (95% CI: [87.9%; 97.0%]) and the positive predictive value 27.3% (95% CI [19.2%; 36.6%]). The accuracy of the model showed an AUC = 0.795 (95% CI [0.668; 0.862]).
Conclusion
The hydrostatic RPP seems to allow a bedside evaluation of ureteral patency after PCNL.
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Falahatkar S, Haghjoo P, Esmaeili S, Kazemnezhad E. Fluoroscopy screening time and radiation dose during complete supine percutaneous nephrolithotomy. World J Urol 2022; 40:2601-2607. [PMID: 36068353 DOI: 10.1007/s00345-022-04138-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/11/2022] [Indexed: 02/01/2023] Open
Abstract
PURPOSE Fluoroscopy-guided percutaneous nephrolithotomy (PCNL) is procedure of choice for treatment of large urinary tract calculi. This study aimed to investigate the affecting factors on fluoroscopy screening time (FST) and radiation dose (RD) of patients undergoing complete supine percutaneous nephrolithotomy (csPCNL). METHODS Analytic cross-sectional study was performed on 355 patients who underwent csPCNL. The correlation between the FST and RD and patients' demographics, stone characteristics, preoperative, intraoperative and postoperative parameters were assessed. Multivariate regression analysis was used to explore various parameters which affect FST and RD. RESULTS Of all 355 patients, 191 (54.65%) were male and 161 were (45.35%) female with mean age of 48.29 ± 12.38 (16-82) years. BMI was 27.61 ± 4.53 (16.61-39.00) kg/m2. The mean operative time was 45.87 ± 18.29 min with mean FST of 101.72 ± 62.00 s. BMI, operative time, success rate, complications, stone number, and tract number had a significant relationship with FST and RD (P < 0.05). On multivariate analysis, BMI, tract number and success rate were found to be independent predictors for FST and RD. Age, gender, operation side, GFR, target calyx, lithotripsy history, stone opacity, size and site, stone configuration and distribution, and hydronephrosis did not have any correlation with FST and RD (P > 0.05). CONCLUSION BMI, success rate and tract number can be significant predictor for FST and RD during csPCNL. Identifying the affecting factors on FST and RD can help the surgeon to minimize the danger of radiation exposure by predicting and preoperative planning.
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Affiliation(s)
- Siavash Falahatkar
- Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Purya Haghjoo
- Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
| | - Samaneh Esmaeili
- Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Ehsan Kazemnezhad
- Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
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10
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Bozkurt M, Seker KG. Fluoroscopy-free RIRS on the second session after ureteral stent placement. Urologia 2022; 90:130-135. [PMID: 36047537 DOI: 10.1177/03915603221114459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Aim: Fluoroscopy is used in some stages of the conventional Retrograde Intrarenal Surgery (RIRS) procedure and is beneficial. On the other hand, radiation exposure is its most obvious disadvantage. As a subgroup, we aimed to show that fluoroscopy-free technique is safe and effective in patients who underwent RIRS after passive dilatation. Materials and methods: Between October 2018 and April 2020, 54 cases of second session RIRS of renal stones performed by a single surgeon were retrospectively evaluated. Patients’ demographic characteristics (age, gender), stone features (laterality, size, number, volume, and location), mean operative time, and, perioperative and postoperative complications, as well as the stone-free rate (SFR), were all retrospectively evaluated. The results were classified as stone free, clinical insignificant residual fragments (CIRF), and presence of residual stones. Complications were graded using the Clavien–Dindo classification system. We used a modified surgical technique. Results: All of complications were minor. There were no major complications (Clavien grade III–IV). The stone-free rate was 70.3% (38/54) on the first day after surgery and 83.3% (45/54) 1 month afterward, respectively. If we accept the absence of residual stone as success, we can say that it is about 91% successful in the first month. Conclusion: This technique has a high stone-free success rate and a low complication rate without the use of radiation. For surgeons experienced in endourology, we can say that the fluoroscopy-free technique is safe and effective in secondary-session RIRS cases which passive dilatation was performed by inserting a ureteral catheter before.
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Affiliation(s)
- Muammer Bozkurt
- Department of Urology, Basaksehir Cam and Sakura City Hospital, Istanbul, Turkey
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11
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Axer B, Garbe S, Hadizadeh DR. Comparative Evaluation of Diagnostic Quality in Native Low-dose CT without and with Spectral Shaping employing a Tin Filter in Urolithiasis with implanted Ureteral Stent. ROFO-FORTSCHR RONTG 2022; 194:1358-1366. [PMID: 35850141 DOI: 10.1055/a-1856-3522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
PURPOSE Spectral shaping employing a tin filter can be used for dose reduction in CT of the abdomen in patients with urolithiasis. As ureteral stents may be in direct contact with the calculus, a good image quality is mandatory. The goal of this study was to obtain data of the effect of tin filtering on image quality and dose in patients with urolithiasis in direct contact with ureteral stents. MATERIALS AND METHODS 84 examinations (conventional low dose vs. modified low dose protocol with tin filtering, randomized) were performed in 65 patients (48 men, 17 women, age 55.0 ± 15.2 years (18-90 years), maximum of one examination per protocol). Image quality and visibility of the calculus was rated on a 5-point-Likert scale by 2 experienced radiologists. Quantitative indicators of image quality were signal-to-noise-(SNR) and contrast-to-noise-ratios (CNR) as well as a figure-of-merit (FOM). RESULTS With a non-inferiority margin of 0.5 points of the 5-point Likert scale, there was non-inferiority of the examinations with tin filter regarding image quality (95 % CI 4.1-4.3, rejection limit 3.5). Non-inferiority regarding visibility of the calculus could be shown (calculus size: 1-2.4 mm: 95 % CI 3.39-4.12; limit 2.73; 2.4-3.8mm: 95 % CI 4.09-4.47; limit 3.65; > 3.8mm: all maximal ratings). Average values of CNR were significantly higher using tin filters (17.0 vs. 10.6). Doses were significantly reduced in the modified protocol (effective dose 1.2 mSv vs. 1.5 mSv; size-specific dose estimate 2.33 mGy vs. 3.09 mGy) with non-significant effect in the subgroup of patients with BMI ≥ 35. CONCLUSION Even with direct contact between a calculus and ureteral stent, radiation reduced examinations by spectral shaping by tin filters are non-inferior to examinations without tin filtering at a concurrent significant dose reduction. KEY POINTS · Spectral shaping by tin filter is suitable for dose reduction.. · The image quality in patients with ureteral stents with tin filtering is non-inferior to that in a conventional low-dose protocol.. CITATION FORMAT · Axer B, Garbe S, Hadizadeh DR. Comparative Evaluation of Diagnostic Quality in Native Low-dose CT without and with Spectral Shaping employing a Tin Filter in Urolithiasis with implanted Ureteral Stent. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1856-3522.
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Affiliation(s)
- Benedikt Axer
- Department of Radiology, Mechernich District Hospital, Mechernich, Germany
| | - Stephan Garbe
- Department of Radiology, University of Bonn, Germany
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12
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Effective dose for kidney-ureter-bladder plain radiography, intravenous urography, and abdominal computed tomography scan: A phantom study. Appl Radiat Isot 2022; 187:110339. [DOI: 10.1016/j.apradiso.2022.110339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 05/07/2022] [Accepted: 06/17/2022] [Indexed: 11/21/2022]
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Ultra-low-dose CTKUB: the new standard of follow-up of ureteric calculi not visible on plain radiograph? Int Urol Nephrol 2022; 54:781-787. [PMID: 35129775 DOI: 10.1007/s11255-022-03134-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 01/27/2022] [Indexed: 10/19/2022]
Abstract
PURPOSE With sensitivities over 95%, non-contrast computer tomography of kidney, ureter and bladder (CTKUB) is the investigation of choice in renal colic to diagnose or exclude ureteric calculi. CTKUB delivers an average effective radiation dose of 5.4 millisievert (mSv) and is used to follow-up calculi not visible on plain X-ray, whereas plain radiography has a radiation exposure of 0.7 mSv and is used to follow-up radio-opaque calculi. We assessed the effectiveness of using ultra-low-dose CTKUB (ULDCTKUB) for the follow-up of ureteric calculi not visible on plain radiograph of the kidneys, ureter and bladder (KUB), as an emerging option to reduce radiation exposure compared to standard dose CTKUB. METHODS Between 2013 and 2016 we retrospectively analysed 86 patients who underwent ULDCTKUB for CTKUB-confirmed ureteric calculi that were not visible on plain radiography. Patients were identified from our Radiology Management System with additional information from electronic patient records. RESULTS 98% of ULDCTKUBs were of diagnostic quality; two patients required further cross-sectional imaging. 67% of patients had passed their calculi after the initial diagnostic CTKUB. In the remaining 33% who had persistent calculi on ULDCTKUB, 20% required surgical intervention and 13% required no intervention. The mean ULDCTKUB effective radiation dose was six times lower than conventional CTKUB (0.8 vs 5.4 mSv). 67% of patients had a radiation dose equivalent to X-ray KUB (< 1 mSv). CONCLUSION ULDCTKUB is a reliable and safe follow-up investigation of ureteric calculi and has absorbed radiation doses similar to plain radiography and lower than annual background radiation. We advocate ULDCTKUB as the primary imaging modality in the follow-up of ureteric calculi not visible on plain radiograph.
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Lee MS, Fenstermaker MA, Naoum EE, Chong S, Van de Ven CJ, Bauer ME, Kountanis JA, Ellis JH, Shields J, Ambani S, Krambeck AE, Roberts WW, Ghani KR. Management of Nephrolithiasis in Pregnancy: Multi-Disciplinary Guidelines From an Academic Medical Center. Front Surg 2021; 8:796876. [PMID: 35028309 PMCID: PMC8751485 DOI: 10.3389/fsurg.2021.796876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 12/02/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: The management of nephrolithiasis during pregnancy can be stressful for urologists due to concerns for investigations and treatments that may pose risk of fetal harm, and unfamiliarity with optimal management of these complex patients. In response, we created multi-disciplinary evidence-based guidelines to standardize the care for obstetric patients presenting with flank pain and suspicion for nephrolithiasis. Methods: A multi-disciplinary team involving Urology, Obstetric Anesthesiology, Obstetrics and Gynecology, Diagnostic Radiology, and Interventional Radiology from a single academic medical center was assembled. A PubMed search was performed using keywords of pregnancy/antepartum, nephrolithiasis/calculi/kidney stones, ureteroscopy, non-obstetric surgery, complications, preterm delivery, MRI, computerized tomography, renal bladder ultrasound (RBUS), and anesthesia to identify relevant articles. Team members reviewed their respective areas to create a comprehensive set of guidelines. One invited external expert reviewed the guidelines for validation purposes. Results: A total of 54 articles were reviewed for evidence synthesis. Four guideline statements were constructed to guide diagnosis and imaging, and seven statements to guide intervention. Guidelines were then used to create a diagnostic and intervention flowchart for ease of use. In summary, RBUS should be the initial diagnostic study. If diagnostic uncertainty still exists, a non-contrast CT scan should be obtained. For obstetric patients presenting with a septic obstructing stone, urgent decompression should be achieved. We recommend ureteral stent placement as the preferred intervention if local factors allow. Conclusions: We present a standardized care pathway for the management of nephrolithiasis during pregnancy. Our aim is to standardize and simplify the clinical management of these complex scenarios for urologists.
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Affiliation(s)
- Matthew S. Lee
- Department of Urology, University of Michigan, Ann Arbor, MI, United States
- Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Michael A. Fenstermaker
- Department of Urology, University of Michigan, Ann Arbor, MI, United States
- Kaiser Permanente Group, Department of Urology, Washington, DC, United States
| | - Emily E. Naoum
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, United States
| | - Suzanne Chong
- Department of Radiology, Indiana University, Indianapolis, IN, United States
| | - Cosmas J. Van de Ven
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, United States
| | - Melissa E. Bauer
- Department of Anesthesiology, Duke University, Durham, NC, United States
| | - Joanna A. Kountanis
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, United States
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - James H. Ellis
- Department of Radiology, University of Michigan, Ann Arbor, MI, United States
| | - James Shields
- Department of Interventional Radiology, University of Michigan, Ann Arbor, MI, United States
| | - Sapan Ambani
- Department of Urology, University of Michigan, Ann Arbor, MI, United States
| | - Amy E. Krambeck
- Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - William W. Roberts
- Department of Urology, University of Michigan, Ann Arbor, MI, United States
| | - Khurshid R. Ghani
- Department of Urology, University of Michigan, Ann Arbor, MI, United States
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Miller DT, Semins MJ. Safety During Ureteroscopy: Radiation, Eyes, and Ergonomics. Front Surg 2021; 8:737337. [PMID: 34778359 PMCID: PMC8580849 DOI: 10.3389/fsurg.2021.737337] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/29/2021] [Indexed: 11/13/2022] Open
Abstract
It is known that urologic surgeons are at risk of work-place injury due to the physical requirements of operating and exposure to hazards. These hazards include radiation, exposure to body fluids, use of laser energy, and orthopedic injury due to the physical nature of operating. The risks that these hazards present can be mitigated by implementing several evidence-based safety measures. The methods to protect against radiation exposure include keeping radiation usage in the operating room as low as reasonably achievable, donning lead aprons, and wearing protective glasses. Additionally, protective glasses decrease the risk of eye injury from laser injury and exposure to body fluids. Finally, practicing sound surgical ergonomics is essential to minimize the risk of orthopedic injury and promote career longevity. The interventions discussed herein are simple and easy to implement in one's daily practice of urology.
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Affiliation(s)
- David T Miller
- Department of Urology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Michelle J Semins
- Department of Urology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
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Chen Q, Chen G, He X, Chong T, Zhou J, Zhang J, Han H, Nan N. Application of ultrasound during electrode implantation for sacral neuromodulation in patients with neurogenic bladder secondary to spinal cord disease: a retrospective study. Int Urol Nephrol 2021; 53:1325-1330. [PMID: 33743121 DOI: 10.1007/s11255-021-02824-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 02/19/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE To compare the use of intraoperative ultrasound with X-ray fluoroscopy during sacral neuromodulation lead electrode placement in patients with neurogenic bladder secondary to spinal cord disease. METHODS We reviewed the medical records of 52 patients who underwent sacral neuromodulation (SNM) lead electrode implantation under fluoroscopy or ultrasound guidance from July 2016 to July 2019. The operating time, number of electrode contacts with stimulus responses, minimum voltage that causes a stimulus response, and rate of standard lead electrode placement were used to assess the differences between the two methods. All patients were evaluated by recording bladder diaries, postvoid residual volumes before and during the testing period. Permanent SNM implantation is acceptable if symptoms improve by at least 50%. RESULTS The operating time decreased from 87.1 ± 25.19 min in the X-ray group to 68.2 ± 25.20 min (p < 0.05) in the ultrasound group. The number of electrode contacts with stimulus responses, rate of standard lead electrode placement, and implantable pulse generator (IPG) placement rate were not significantly different between the two groups (p > 0.05). There was no radiation exposure during the operation in the ultrasound group. No incisional infections, hematomas, or other critical complications were reported in either groups. CONCLUSION Ultrasound can be applied to safely place lead electrode for sacral neuromodulation and leads to no radiation exposure to the patient, surgeon, and operating room staff and a shortened operating time while maintaining the same efficacy as X-ray.
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Affiliation(s)
- Qi Chen
- Department of Urology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, Shaanxi, China
| | - Guoqing Chen
- Department of Urology, China Rehabilitation Research Center, Beijing, 100068, China.
| | - Xijing He
- Department of Orthopedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, Shaanxi, China.
| | - Tie Chong
- Department of Urology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, Shaanxi, China
| | - Jinsong Zhou
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Jianshui Zhang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Hua Han
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Ning Nan
- Department of Urology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, Shaanxi, China
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17
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Miller DT, Semins MJ. Minimizing radiation dose in management of stone disease: how to achieve 'ALARA'. Curr Opin Urol 2021; 31:115-119. [PMID: 33394609 DOI: 10.1097/mou.0000000000000845] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Exposure to radiation is known to have adverse effects such as secondary malignancies. Patients with nephrolithiasis are exposed to radiation in the workup and treatment of their condition. Furthermore, exposure to radiation is often repeated due to the high recurrence rate of nephrolithiasis. RECENT FINDINGS We discuss practices inside and outside of the operating room to strive to keep radiation exposure as low as reasonably achievable (ALARA) for patients being treated for nephrolithiasis. These efforts include reduced dose computed tomography scans, fluoroless surgical techniques and new alternative technologies. SUMMARY Maintaining radiation exposure ALARA for our patients is increasingly practical. The urologist must make every effort to adhere to ALARA principles to protect patients from the stochastic effects of radiation.
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Affiliation(s)
- David T Miller
- Department of Urology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
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18
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Yang B, Suhail N, Marais J, Brewin J. Do low dose CT-KUBs really expose patients to more radiation than plain abdominal radiographs? Urologia 2021; 88:362-368. [PMID: 33583356 DOI: 10.1177/0391560321994443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Urolithiasis patients often require frequent urinary tract imaging, leading to high radiation exposure. CT Kidney-Ureter-Bladder (CT-KUB) is the gold standard in urolithiasis detection, however it is thought to harbour significant radiation load. Urologists have therefore utilised abdominal radiographs (XR-KUB) as an alternative, though with markedly lower sensitivity and specificity. We present the first contemporary UK study comparing the effective doses of XR-KUBs with low dose CT-KUBs. METHOD Fifty-three patients were retrospectively identified in a single centre who underwent both a XR-KUB and a CT-KUB in 2018. Effective-Dose was measured by converting the recorded 'Dose Area/Length Product' via the International Commission on Radiological Protection formula. RESULTS The average effective dose of XR-KUBs and low dose CT-KUBs were 5.10 mSv and 5.31 mSv respectively. Thirty-four percent (18/53) of patients had a XR-KUBs with a higher effective dose than their low dose CT-KUB. Patients with higher Weight, BMI and AP diameter had higher effective doses for both their XR and low dose CT-KUBs. All patients in our study weighing over 92 kg or with a BMI greater than 32 had a XR-KUBs with a higher effective dose than their low dose CT-KUB. CONCLUSION This data supports moving away from XR-KUBs for the investigation of urolithiasis, particularly in patients with a high BMI.
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Affiliation(s)
- Bob Yang
- Salisbury District Hospital, Salisbury, UK
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Danilovic A, Nunes E, Lipkin ME, Ferreira T, Torricelli FCM, Marchini GS, Srougi M, Nahas WC, Mazzucchi E. Low Dose Fluoroscopy During Ureteroscopy Does Not Compromise Surgical Outcomes. J Endourol 2020; 33:527-532. [PMID: 30793920 DOI: 10.1089/end.2018.0722] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Objective: To evaluate whether reducing the dose of fluoroscopy to ¼ of standard dose during unilateral ureteroscopy for ureteral stone treatment would impact in a reduction of total radiation emitted and whether this strategy would impact operation time, stone-free rate, and complication rate. Methods: From August 2016 to August 2017, patients over 18 years submitted to ureteroscopy for ureteral stone between 5 and 20 mm were prospectively randomized for ¼ dose reduction or standard dose fluoroscopy. Patients with abnormal urinary anatomy such as horseshoe kidney, pelvic kidney, or duplex system were excluded from the study. Results: Ninety-four patients were enrolled. The fluoroscopic dose reduction strategy to ¼ of the standard dose was able to significantly reduce the cumulative radiation emitted by C-arm fluoroscopy and the dose area product (3.6 ± 4.5 mGy vs 16.2 ± 19.3 mGy, p = 0.0001 and 0.23 ± 0.52 mcGycm2 vs 1.15 ± 2.74 mcGycm2, p = 0.02, respectively). Fluoroscopy time was similar between groups (74.5 ± 84.8 seconds vs 88.3 ± 90 seconds, p = 0.44). There was no need to increase the fluoroscopy dose during any of the procedures. Surgical outcomes were not affected by fluoroscopic dose reduction strategy. Conclusion: Low dose fluoroscopy reduces the emitted radiation during ureteroscopy without compromising surgical outcomes.
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Affiliation(s)
- Alexandre Danilovic
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Eduardo Nunes
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Michael E Lipkin
- 2 Division of Urologic Surgery, Surgery Department, Duke University Medical Center, Durham, North Carolina
| | - Thiago Ferreira
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Fabio C M Torricelli
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Giovanni S Marchini
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Miguel Srougi
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - William C Nahas
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Eduardo Mazzucchi
- 1 Department of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, Sao Paulo, Brazil
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Birowo P, Raharja PAR, Putra HWK, Rustandi R, Atmoko W, Rasyid N. X-ray-free Ultrasound-guided Percutaneous Nephrolithotomy in Supine Position Using Alken Metal Telescoping Dilators in a Large Kidney Stone: A Case Report. Res Rep Urol 2020; 12:287-293. [PMID: 32802805 PMCID: PMC7399460 DOI: 10.2147/rru.s259941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/07/2020] [Indexed: 12/23/2022] Open
Abstract
X-ray-free ultrasound-guided percutaneous nephrolithotomy (PCNL) has been proven to be safe, feasible, and affordable. Kidney dilatation during X-ray-free ultrasound-guided PCNL is mostly using balloon dilators. This report presents our experience of performing X-ray-free ultrasound-guided PCNL in supine position using Alken metal telescopic dilators in a patient with a large kidney stone. A 50-year-old male presented with right complete staghorn stone sized 46×30×24 mm (stone burden: 50,985 mm3 with sphere formula) and grade II hydronephrosis. The computed tomography (CT) scan showed no right ureteric stone, kinking, or stenosis. Ureteral catheter and guidewire were placed retrogradely under ultrasound guidance during cystoscopy. Normal saline was pumped via the ureteral catheter to make artificial hydronephrosis thus assisting the process. Kidney dilatation was performed with Alken metal telescoping dilators. Urine flow from the dilators confirmed that our dilator had reached the collecting system. The stone was identified and fragmented with combination of both pneumatic and shock pulse lithotripter. Double J stent and nephrostomy tubes were inserted at the end of the procedure. All of the steps were performed purely under ultrasound guidance. There was no residual stone after the procedure, confirmed by ultrasound, nephroscope, and postoperative X-ray. There was no significant complication during or after the procedure. The patient was discharged on postoperative day two. X-ray-free ultrasound-guided PCNL in supine position using Alken metal telescoping dilators seems to be a feasible, safe, and cost-effective approach in managing kidney stones, including staghorn and large stones.
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Affiliation(s)
- Ponco Birowo
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
| | - Putu Angga Risky Raharja
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
| | - Harun Wijanarko Kusuma Putra
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
| | - Reginald Rustandi
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
| | - Widi Atmoko
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
| | - Nur Rasyid
- Department of Urology, Faculty of Medicine, Universitas Indonesia, Cipto Mangunkusumo Hospital, Jakarta10430, Indonesia
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Radiation exposure during retrograde intrarenal surgery (RIRS): a prospective multicenter evaluation. World J Urol 2020; 39:217-224. [PMID: 32200411 PMCID: PMC7858553 DOI: 10.1007/s00345-020-03160-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 03/06/2020] [Indexed: 12/29/2022] Open
Abstract
Purpose Retrograde intrarenal surgery (RIRS) may require extensive X-ray usage. We evaluated the impact of preoperative surgeon briefing regarding the inclusion and evaluation of fluoroscopy time (FT) and dose area product (DAP) in a multicenter study on the applied X-ray usage. Methods A prospective multicenter study of 6 tertiary centers was performed. Each center recruited up to 25 prospective patients with renal stones of any size for RIRS. Prior to study´s onset, all surgeons were briefed about hazards of radiation and on strategies to avoid high doses in RIRS. Prospective procedures were compared to past procedures, as baseline data. FT was defined as the primary outcome. Secondary parameters were stone-free rate (SFR), complications according to the Clavien, SATAVA and postureteroscopic lesion scale. Results were analyzed using T test, chi-squared test, univariate analysis and confirmed in a multivariate regression model. Results 303 patients were included (145 retro- and 158 prospective). Mean FT and DAP were reduced from 130.8 s/565.8 to 77.4 s/357.8 (p < 0.05). SFR was improved from 85.5% to 93% (p < 0.05). Complications did not vary significantly. Neither stone position (p = 0.569), prestenting (p = 0.419), nor surgeons’ experience (> 100 RIRS) had a significant impact on FT. Significant univariate parameters were confirmed in a multivariate model, revealing X-ray training to be radiation protective (OR − 44, p = 0.001). Conclusions Increased surgeon awareness of X-ray exposure risks has a significant impact on FT and DAP. This “awareness effect” is a simple method to reduce radiation exposure for the patient and OR staff without the procedures´ outcome and safety being affected.
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Very low-dose computerized tomography for confirmation of urinary stone presence. World J Urol 2020; 39:233-238. [PMID: 32124021 DOI: 10.1007/s00345-020-03142-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 02/19/2020] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To determine whether a modified non-contrast very low-dose computed tomography (VLD-CT) protocol is applicable for confirmation of known urolithiasis. METHODS AND MATERIALS Consecutive adult patients with a CT scan showing urinary tract stone(s) between 6/2017-12/2018 were included. They were referred to a modified VLD-CT protocol if stone presence was equivocal or if stone location needed reassessment before an endourological interventional procedure. The scanned area was limited to the level of initial stone location caudally. Data on patients' demographics andbody mass index, were collected. The scanned length and radiation dose were calculated. Images were reviewed by two radiologists who assessed stone size and location. Follow-up reference standard included stone passage, surgical removal, and other imaging and clinical information. RESULTS Sixty-three patients [63 stones, mean BMI 28.7 (range 19-41.9)] were included. VLD-CTs revealed 31 stones in 31 patients, with a mean stone length of 5.5 mm. Fifteen stones remained at the same location, and 16 had migrated, of which two appeared in the bladder. Thirty-two stones were not observed on VLD-CT. The mean span scanned on the VLD-CT was 274 mm (± 80). The average radiation exposure was 1.47 mGy (range 1.09-3.3), and the absorbed dose was 0.77 mSv (range 0.39-1.43), compared to 10.24 mGy (range 1.75-28.9) and 7.87 mSv (range 1.44-18.5) in the previous scan. The mean radiation dose reduction between scans was 89%. On follow-up, all VLD-CT findings were confirmed. CONCLUSION A modified imaging protocol is applicable for confirmation of stone presence and location by utilizing very low-dose radiation exposure.
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Abstract
PURPOSE OF REVIEW Burst wave lithotripsy and ultrasonic propulsion of kidney stones are novel, noninvasive emerging technologies to separately or synergistically fragment and reposition stones in an office setting. The purpose of this review is to discuss the latest refinements in technology, to update on testing of safety and efficacy, and to review future applications. RECENT FINDINGS Burst wave lithotripsy produced consistent, small passable fragments through transcutaneous applications in a porcine model, while producing minimal injury and clinical trials are now underway. A more efficient ultrasonic propulsion design that can also deliver burst wave lithotripsy effectively repositioned 95% of stones in 18 human participants (18 of 19 kidneys) and clinical trials continue. Acoustic tractor beam technology is an emerging technology with promising clinical applications through the manipulation of macroscopic objects. SUMMARY The goal of the reviewed work is an office-based system to image, fragment, and reposition urinary stones to facilitate their natural passage. The review highlights progress in establishing safety, effectiveness, and clinical benefit of these new technologies. The work is also anticipating challenges in clinical trials and developing the next generation of technology to improve on the technology as it is being commercialized today.
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Affiliation(s)
- Tony T. Chen
- Department of Urology, University of Washington, Seattle, WA, USA
| | | | | | - Michael R. Bailey
- Department of Urology, University of Washington, Seattle, WA, USA
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
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Substantial radiation dose reduction with consistent image quality using a novel low-dose stone composition protocol. World J Urol 2020; 38:2971-2979. [PMID: 31993735 DOI: 10.1007/s00345-020-03082-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 01/06/2020] [Indexed: 10/25/2022] Open
Abstract
PURPOSE To assess a novel low-dose CT-protocol, combining a 150 kV spectral filtration unenhanced protocol (Sn150 kVp) and a stone-targeted dual-energy CT (DECT) in patients with urolithiasis. METHODS 232 (151 male, 49 ± 16.4 years) patients with urolithiasis received a low-dose non-contrast enhanced CT (NCCT) for suspected urinary stones either on a third-generation dual-source CT system (DSCT) using Sn150 kVp (n = 116, group 1), or on a second-generation DSCT (n = 116 group 2) using single energy (SE) 120 kVp. For group 1, a subsequent dual-energy CT (DECT) with a short stone-targeted scan range was performed. Objective and subjective image qualities were assessed. Radiation metrics were compared. RESULTS 534 stones (group 1: n = 242 stones; group 2: n = 292 stones) were found. In group 1, all 215 stones within the stone-targeted DECT-scan range were identified. DE analysis was able to distinguish between UA and non-UA calculi in all collected stones. 11 calculi (5.12%) were labeled as uric acid (UA) while 204 (94.88%) were labeled as non-UA calculi. There was no significant difference in overall Signal-to-noise-ratio between group 1 and group 2 (p = 0.819). On subjective analysis both protocols achieved a median Likert rating of 2 (p = 0.171). Mean effective dose was significantly lower for combined Sn150 kVp and stone-targeted DECT (3.34 ± 1.84 mSv) compared to single energy 120 kVp NCCT (4.45 ± 2.89 mSv) (p < 0.001), equaling a 24.9% dose reduction. CONCLUSION The evaluated novel low-dose stone composition protocol allows substantial radiation dose reduction with consistent high diagnostic image quality.
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Ding X, Hao Y, Jia Y, Hou Y, Wang C, Wang Y. 3-dimensional ultrasound-guided percutaneous nephrolithotomy: total free versus partial fluoroscopy. World J Urol 2019; 38:2295-2300. [DOI: 10.1007/s00345-019-03007-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 10/31/2019] [Indexed: 12/23/2022] Open
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Simson N, Stonier T, Suleyman N, Hendry J, Salib M, Peacock J, Connor M, Jones O, Schuster-Bruce J, Bottrell O, Lovegrove C, English L, Hamami H, Horn C, Bagley J, Bareh A, Jaikaransingh D, Mohamed N, Ukwu U, Shanmugathas N, Batura D, McDonald J, Charitopoulos K, Graham A, Zakikhani P, Taneja S, Sells H, Bolgeri M, Wiseman O, Bycroft J, Qteishat A, Aboumarzouk O. Defining a national reference level for intraoperative radiation exposure in urological procedures: FLASH, a retrospective multicentre UK study. BJU Int 2019; 125:292-298. [PMID: 31437345 DOI: 10.1111/bju.14903] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Nick Simson
- Department of Urology; Guy's Hospital; London UK
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Seitz C, Bach T, Bader M, Berg W, Knoll T, Neisius A, Netsch C, Nothacker M, Schmidt S, Schönthaler M, Siener R, Stein R, Straub M, Strohmaier W, Türk C, Volkmer B. Aktualisierung der S2k-Leitlinie zur Diagnostik, Therapie und Metaphylaxe der Urolithiasis (AWMF Registernummer 043-025). Urologe A 2019; 58:1304-1312. [DOI: 10.1007/s00120-019-01033-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Zusammenfassung
Die Zunahme des medizinischen Wissens, technische Neuerungen gemeinsam mit demographischem Wandel stellen eine Herausforderung an die Neukonzeption von Leitlinien und klinischen Studien dar. Die vorliegende S2k-Leitlinie, die sich ausschließlich mit Nieren- und Harnleitersteinen beschäftigt, soll die Behandlung von Harnsteinpatienten in Klinik und Praxis unterstützen, aber auch Patienteninformationen zur Urolithiasis geben. Die zunehmende interdisziplinäre Zusammenarbeit in der Steintherapie zeigt sich auch an der Anzahl beteiligter Fachgruppen und Arbeitsgemeinschaften in der Erstellung des neuen Leitlinienupdates. Die vorliegende, aus einem interdisziplinären Konsensusprozess hervorgegangene S2k-Leitlinie stellt die aktuellen Empfehlungen praxisnah dar und gibt Entscheidungshilfen für Diagnostik‑, Therapie- und Metaphylaxemaßnahmen auf Basis von Expertenmeinungen und verfügbaren Evidenzgrundlagen aus der Literatur.
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Fukuhara H, Kobayashi T, Takai S, Tawara T, Kikuta M, Sugiura A, Yamagishi A, Toyohara T, Nakane M, Tsuchiya N. External validation of the CHOKAI score for the prediction of ureteral stones: A multicenter prospective observational study. Am J Emerg Med 2019; 38:920-924. [PMID: 31337599 DOI: 10.1016/j.ajem.2019.07.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 06/27/2019] [Accepted: 07/14/2019] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE The CHOKAI and STONE scores are clinical prediction rules to predict ureteral stones in patients presenting with renal colic. Both systems contribute to reducing diagnostic radiation exposure; however, few studies have compared the two scoring systems. Therefore, we aimed to compare these systems and assess their diagnostic accuracy for ureteral stones. METHODS This was a multicenter prospective observational study performed between 2017 and 2018, including patients aged >15 years with renal colic and suspected with ureteral stones. We calculated the CHOKAI and STONE scores of each patient based on their medical interviews and physical and laboratory findings. Primary outcome was differences in the area under the receiver operating characteristic curve in each model, and secondary outcome was diagnostic accuracy at the optimal cut-off point. RESULTS Of the 124 patients included, 84 were diagnosed with ureteral stones. The area under the curve of the CHOKAI score was 0.95, showing a sensitivity of 0.93, specificity of 0.90, positive likelihood ratio of 9.3, and negative likelihood ratio of 0.079, at an optimal cut-off point of 6. The area under the curve of the STONE score was 0.88, showing a sensitivity of 0.68, specificity of 0.90, positive likelihood ratio of 6.8, and negative likelihood ratio of 0.36, at an optimal cut-off point of 9. Thus, the area under the curve was significantly higher for the CHOKAI score than for the STONE score (p = 0.0028). CONCLUSIONS The CHOKAI score has a diagnostic performance superior to that of the STONE score in this population.
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Affiliation(s)
- Hiroki Fukuhara
- Department of Urology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata Prefecture 990-9585, Japan.
| | - Tadahiro Kobayashi
- Department of Emergency and Critical Care Medicine, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata Prefecture 998-9585, Japan
| | - Satoshi Takai
- Department of Urology, Nihonkai General Hospital, 30 Akiho-cho, Sakata City, Yamagata Prefecture 998-8501, Japan
| | - Toshihiro Tawara
- Department of Emergency, Hakodate Municipal Hospital, 1-10-1, Minatomachi, Hakodate City, Hokkaido 041-8680, Japan
| | - Masato Kikuta
- Department of Urology, Okitama General Hospital, 2000 Nishi-otsuka, Kawanishi Town, Yamagata Prefecture 992-0601, Japan
| | - Asumi Sugiura
- Department of Emergency, Yamagata Prefectural Central Hospital, 1800 Aoyagi, Yamagata City, Yamagata Prefecture 990-2292, Japan.
| | - Atsushi Yamagishi
- Department of Urology, Yamagata City Hospital Saiseikan, 1-3-26 Nanokamachi, Yagmagata City, Yamagata Prefecture 990-8533, Japan
| | - Tsubasa Toyohara
- Department of Emergency, Kushiro City General Hospital, 1-12 Shunkodai, Kushiro City, Hokkaido 085-0822, Japan
| | - Masaki Nakane
- Department of Emergency and Critical Care Medicine, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata Prefecture 998-9585, Japan.
| | - Norihiko Tsuchiya
- Department of Urology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata Prefecture 990-9585, Japan
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Fiechter S, Geissbühler E, Bähler A, Obmann V, Meierhans S, Exadaktylos AK, Christe A, Thalmann GN, Roth B. Identification of ureteral stones at reduced radiation exposure: a pilot study comparing conventional versus digital low-dosage linear slot scanning (Lodox ®) radiography. World J Urol 2019; 38:1065-1071. [PMID: 31165230 DOI: 10.1007/s00345-019-02803-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 05/04/2019] [Indexed: 02/04/2023] Open
Abstract
PURPOSE Digital low-dosage, linear slot scanning radiography (Lodox®) is an imaging modality that can emit down to one-tenth the radiation of conventional X-ray systems. We prospectively evaluated Lodox® as a diagnostic imaging modality in patients with ureterolithiasis. METHODS Conventional kidney-ureter-bladder (KUB) X-ray and Lodox® were performed in 41 patients presenting with acute flank pain due to unilateral ureteral stone confirmed by computed tomography. KUB X-ray and Lodox® images were then reviewed by four blinded readers (urology expert/resident, radiology expert/resident). Identification rates were compared using Pearson's Chi square test. The impact of different parameters on stone identification by Lodox® was evaluated using logistic regression and generalized linear mixed models. Inter-reader agreement was tested using Cohen's kappa coefficient. RESULTS Median stone size was 5 mm (range 2-12), median stone density was 800 HU (range 200-1500). The identification rates of the urology expert were 68% for KUB X-ray and 90% for Lodox® (p = 0.014), and for all four readers 61% for KUB X-ray and 62% for Lodox® (p = 0.8). Radiation exposure for KUB X-ray and Lodox® was 0.45 mSv (SD ± 0.64) and 0.027 mSv (SD ± 0.038), respectively. Multivariable analyses showed an association between stone identification by Lodox® and stone size (p < 0.001), stone density (p = 0.005), lower body mass index (p = 0.005), and reader (p < 0.001). CONCLUSIONS The high identification rates and low radiation doses of Lodox® make it a promising imaging modality for the diagnosis of ureteral stones. Further validation in larger cohorts, including performance evaluation for renal stones, is warranted. TRIAL REGISTRATION http://www.controlled-trails.com/ISRCTN12915426.
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Affiliation(s)
| | - Elio Geissbühler
- Department of Urology, University of Bern, 3010, Bern, Switzerland
| | | | - Verena Obmann
- Department of Radiology, University of Bern, Bern, Switzerland
| | - Susan Meierhans
- Department of Urology, University of Bern, 3010, Bern, Switzerland
| | | | - Andreas Christe
- Department of Radiology, University of Bern, Bern, Switzerland
| | | | - Beat Roth
- Department of Urology, University of Bern, 3010, Bern, Switzerland. .,Department of Urology, University Hospital of Lausanne (CHUV), University of Lausanne, Lausanne, Switzerland.
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30
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Tzou DT, Zetumer S, Usawachintachit M, Taguchi K, Bechis SK, Duty BD, Harper JD, Hsi RS, Sorensen M, Sur RL, Reliford-Titus S, Chang HC, Isaacson D, Bayne DB, Wang ZJ, Stoller ML, Chi T. Computed Tomography Radiation Exposure Among Referred Kidney Stone Patients: Results from the Registry for Stones of the Kidney and Ureter. J Endourol 2019; 33:619-624. [PMID: 31030576 DOI: 10.1089/end.2019.0091] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Purpose: Kidney stone patients routinely have CT scans during diagnostic work-up before being referred to a tertiary center. How often these patients exceed the recommended dose limits for occupational radiation exposure of >100 mSv for 5 years and >50 mSv in a single year from CT alone remains unknown. This study aimed to quantify radiation doses from CTs received by stone patients before their evaluation at a tertiary care stone clinic. Methods: From November 2015 to March 2017, consecutive new patients enrolled into the Registry for Stones of the Kidney and Ureter (ReSKU™) had the dose-length product of every available CT abdomen/pelvis within 5 years of their initial visit recorded, allowing for an effective dose (EDose) calculation. Multivariate logistic regression analysis identified factors associated with exceeding recommended dose limits. Models were created to test radiation reducing effects of low-dose and phase-reduction CT protocols. Results: Of 343 noncontrast CTs performed, only 29 (8%) were low-dose CTs (calculated EDose <4 mSv). Among 389 total patients, 101 (26%) and 25 (6%) had an EDose >20 mSv and >50 mSv/year, respectively. Increased body mass index, number of scans, and multiphase scans were associated with exceeding exposure thresholds (p < 0.01). The implementation of a low-dose CT protocol decreased the estimated number of scans contributing to overexposure by >50%. Conclusions: Stone patients referred to a tertiary stone center may receive excessive radiation from CT scans alone. Unnecessary phases and underutilization of low-dose CT protocols continue to take place. Enacting new approaches to CT protocols may spare stone patients from exceeding recommended dose limits.
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Affiliation(s)
- David T Tzou
- 1 Department of Urology, University of California, San Francisco, San Francisco, California.,2 Division of Urology, Department of Surgery, University of Arizona College of Medicine, Tucson, Arizona
| | - Samuel Zetumer
- 1 Department of Urology, University of California, San Francisco, San Francisco, California
| | - Manint Usawachintachit
- 1 Department of Urology, University of California, San Francisco, San Francisco, California.,3 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand
| | - Kazumi Taguchi
- 1 Department of Urology, University of California, San Francisco, San Francisco, California.,4 Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Seth K Bechis
- 5 Department of Urology, University of California, San Diego, San Diego, California
| | - Brian D Duty
- 6 Department of Urology, Oregon Health & Science University, Portland, Oregon
| | - Jonathan D Harper
- 7 Department of Urology, University of Washington, Seattle, Washington
| | - Ryan S Hsi
- 8 Department of Urology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Mathew Sorensen
- 7 Department of Urology, University of Washington, Seattle, Washington
| | - Roger L Sur
- 5 Department of Urology, University of California, San Diego, San Diego, California
| | | | - Helena C Chang
- 7 Department of Urology, University of Washington, Seattle, Washington
| | - Dylan Isaacson
- 1 Department of Urology, University of California, San Francisco, San Francisco, California
| | - David B Bayne
- 1 Department of Urology, University of California, San Francisco, San Francisco, California
| | - Zhen J Wang
- 9 Department of Radiology, University of California, San Francisco, San Francisco, California
| | - Marshall L Stoller
- 1 Department of Urology, University of California, San Francisco, San Francisco, California
| | - Thomas Chi
- 1 Department of Urology, University of California, San Francisco, San Francisco, California
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Image Quality and Patient-Specific Organ Doses in Stone Protocol CT: A Comparison of Traditional CT to Low Dose CT with Iterative Reconstruction. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5120974. [PMID: 30363655 PMCID: PMC6181004 DOI: 10.1155/2018/5120974] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/16/2018] [Indexed: 02/03/2023]
Abstract
Objective To compare organ specific radiation dose and image quality in kidney stone patients scanned with standard CT reconstructed with filtered back projection (FBP-CT) to those scanned with low dose CT reconstructed with iterative techniques (IR-CT). Materials and Methods Over a one-year study period, adult kidney stone patients were retrospectively netted to capture the use of noncontrasted, stone protocol CT in one of six institutional scanners (four FBP and two IR). To limit potential CT-unit use bias, scans were included only from days when all six scanners were functioning. Organ dose was calculated using volumetric CT dose index and patient effective body diameter through validated conversion equations derived from previous cadaveric, dosimetry studies. Board-certified radiologists, blinded to CT algorithm type, assessed stone characteristics, study noise, and image quality of both techniques. Results FBP-CT (n=250) and IR-CT (n=90) groups were similar in regard to gender, race, body mass index (mean BMI = 30.3), and stone burden detected (mean size 5.4 ± 1.2 mm). Mean organ-specific dose (OSD) was 54-62% lower across all organs for IR-CT compared to FBP-CT with particularly reduced doses (up to 4.6-fold) noted in patients with normal BMI range. No differences were noted in radiological assessment of image quality or noise between the cohorts, and intrarater agreement was highly correlated for noise (AC2=0.873) and quality (AC2=0.874) between blinded radiologists. Conclusions Image quality and stone burden assessment were maintained between standard FBP and low dose IR groups, but IR-CT decreased mean OSD by 50%. Both urologists and radiologists should advocate for low dose CT, utilizing reconstructive protocols like IR, to reduce radiation exposure in their stone formers who undergo multiple CTs.
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32
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Bayne DB, Usawachintachit M, Tzou D, Taguchi K, Shindel A, Chi TL. Increasing Body Mass Index Steepens the Learning Curve for Ultrasound-guided Percutaneous Nephrolithotomy. Urology 2018; 120:68-73. [PMID: 30077540 DOI: 10.1016/j.urology.2018.07.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/11/2018] [Accepted: 07/23/2018] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To define how the learning curve for success in ultrasound-guided percutaneous nephrolithotomy (PCNL) is impacted by body mass index (BMI). Previous research has shown ultrasound-guided PCNL to be an effective method of nephrolithiasis treatment comparable to fluoroscopy-guided PCNL. A common concern for the ultrasound-guided approach is potential imaging difficulty in the obese patient population. METHODS A prospective cohort study of consecutive patients undergoing PCNL with ultrasound guidance for renal tract access was performed. Clinical data collected included success in gaining renal access with ultrasound guidance, patient BMI, and clinical outcomes over time. Nonparametric LOWESS regression modeling was performed in R using locally weighted scatterplot smoother (R version 3.3.3) for gradations of patients by BMI group (<30, 30-40, and >40). RESULTS A total of 150 cases were examined. Case number and BMI were evaluated as continuous variables. Multivariate logistic regression revealed that BMI (P = .010; OR 0.93) and case number (P<.001; OR 1.03) were significantly correlated with ultrasound success. Sex, age, hydronephrosis, stone type, puncture location, and stone size did not influence success at obtaining ultrasound-only access in a statistically significant fashion. LOWESS regression modeling of the relationship between case number and renal access success depicts that the curve representative of the BMI >40 group is downward and right-shifted relative to the other two groups. CONCLUSION The learning curve for successful ultrasound-guided PCNL is impacted by patient's BMI as well as case number. Increasing BMI makes access more challenging when performing ultrasound-guided PCNL.
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Affiliation(s)
- David B Bayne
- Department of Urology, University of California, San Francisco, San Francisco, CA.
| | | | - David Tzou
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Kazumi Taguchi
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Alan Shindel
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Thomas L Chi
- Department of Urology, University of California, San Francisco, San Francisco, CA
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Thomas A, Ewald J, Kelly I, Pierce M, Thomas J, Mattison B, West B, Ruckle D, Keheila M, Abourbih S, Krause R, Dinh VA, Baldwin DD, Baldwin DD. Conventional vs Computer-Assisted Stereoscopic Ultrasound Needle Guidance for Renal Access: A Randomized Crossover Bench-Top Trial. J Endourol 2018; 32:424-430. [DOI: 10.1089/end.2018.0015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- Alexander Thomas
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Jonathan Ewald
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Isaac Kelly
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Matthew Pierce
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Jerry Thomas
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Braden Mattison
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Benjamin West
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - David Ruckle
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Mohamed Keheila
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Samuel Abourbih
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Reed Krause
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - Vi Am Dinh
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - D. Daniel Baldwin
- Department of Urology, Loma Linda University Health, Loma Linda, California
| | - D. Duane Baldwin
- Department of Urology, Loma Linda University Health, Loma Linda, California
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Assimos DG. Re: Evaluation of Kidney Stones with Reduced-Radiation Dose CT: Progress from 2011-2012 to 2015-2016—Not There Yet. J Urol 2018. [DOI: 10.1016/j.juro.2017.11.088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Shakuri-Rad J, Cicic A, Thompson J. Prospective randomized study evaluating ultrasound versus fluoroscopy guided sacral InterStim® lead placement: A pilot study. Neurourol Urodyn 2018; 37:1737-1743. [PMID: 29464748 DOI: 10.1002/nau.23502] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 12/26/2017] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To investigate the use of intraoperative ultrasound during stage I InterStim® sacral lead placement. METHODS A total of 40 patients were randomly assigned to undergo InterStim® lead placement utilizing fluoroscopy or ultrasound guidance. Patients were blinded for the duration of the study. The surgeon and staff were blinded until after induction of anesthesia. Patients met criteria for refractory overactive bladder, fecal incontinence, or both. The ICIQ-OABqol, OABSS, and FIQL validated questionnaires were used pre- and post-operatively. Primary endpoint was total fluoroscopy time. Secondary endpoints were total radiation exposure and total number of foramen needle skin punctures. RESULTS Forty patients were enrolled, twenty in the ultrasound and twenty in the fluoroscopy only arm. Mean age was 60 (SD = 14.4) and mean BMI 32 (SD = 7.2). Twenty-seven patients (67.5%) had urinary symptoms, four (10%) fecal incontinence, and nine (22.5%) had mixed symptoms. Radiation exposure time was reduced by 70.5 s (P = 0.002), radiation exposure was decreased by 42.3 mGy (P = 0.017), and the number of needle skin punctures decreased by 3.6 (P = 0.035) with use of ultrasound. Mean OR time in minutes was 55.5 in ultrasound and 58.2 in fluoroscopy group (P = 0.53). There were no statistically significant differences in questionnaire scores between groups. CONCLUSION Ultrasound guided placement of foramen needle during Stage I sacral neuromodulation results in reduction of radiation exposure to the patient, surgeon, and operating room staff. Further studies are necessary to determine the learning curve and efficacy of this technique.
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Affiliation(s)
- Jaschar Shakuri-Rad
- University of Michigan Health, Metro Health Hospital, Byron Center, Wyoming, Michigan
| | - Arman Cicic
- University of Michigan Health, Metro Health Hospital, Byron Center, Wyoming, Michigan
| | - Jannah Thompson
- University of Michigan Health, Metro Health Hospital, Byron Center, Wyoming, Michigan
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Chi T, Usawachintachit M, Weinstein S, Kohi MP, Taylor A, Tzou DT, Chang HC, Stoller M, Mongan J. Contrast Enhanced Ultrasound as a Radiation-Free Alternative to Fluoroscopic Nephrostogram for Evaluating Ureteral Patency. J Urol 2017; 198:1367-1373. [PMID: 28743528 DOI: 10.1016/j.juro.2017.07.074] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2017] [Indexed: 12/19/2022]
Abstract
PURPOSE We compared contrast enhanced ultrasound and fluoroscopic nephrostography in the evaluation of ureteral patency following percutaneous nephrolithotomy. MATERIALS AND METHODS This prospective cohort, noninferiority study was performed after obtaining institutional review board approval. We enrolled eligible patients with kidney and proximal ureteral stones who underwent percutaneous nephrolithotomy at our center. On postoperative day 1 patients received contrast enhanced ultrasound and fluoroscopic nephrostogram within 2 hours of each other to evaluate ureteral patency, which was the primary outcome of this study. RESULTS A total of 92 pairs of imaging studies were performed in 82 patients during the study period. Five study pairs were excluded due to technical errors that prevented imaging interpretation. Females slightly predominated over males with a mean ± SD age of 50.5 ± 15.9 years and a mean body mass index of 29.6 ± 8.6 kg/m2. Of the remaining 87 sets of studies 69 (79.3%) demonstrated concordant findings regarding ureteral patency for the 2 imaging techniques and 18 (20.7%) were discordant. The nephrostomy tube was removed on the same day in 15 of the 17 patients who demonstrated antegrade urine flow only on contrast enhanced ultrasound and they had no subsequent adverse events. No adverse events were noted related to ultrasound contrast injection. While contrast enhanced ultrasound used no ionizing radiation, fluoroscopic nephrostograms provided a mean radiation exposure dose of 2.8 ± 3.7 mGy. CONCLUSIONS A contrast enhanced ultrasound nephrostogram can be safely performed to evaluate for ureteral patency following percutaneous nephrolithotomy. This imaging technique was mostly concordant with fluoroscopic findings. Most discordance was likely attributable to the higher sensitivity for patency of contrast enhanced ultrasound compared to fluoroscopy.
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Affiliation(s)
- Thomas Chi
- Department of Urology, University of California-San Francisco, California.
| | - Manint Usawachintachit
- Department of Urology, University of California-San Francisco, California; Division of Urology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Stefanie Weinstein
- Department of Radiology and Biomedical Imaging, University of California-San Francisco, California
| | - Maureen P Kohi
- Department of Radiology and Biomedical Imaging, University of California-San Francisco, California
| | - Andrew Taylor
- Department of Radiology and Biomedical Imaging, University of California-San Francisco, California
| | - David T Tzou
- Department of Urology, University of California-San Francisco, California
| | - Helena C Chang
- Department of Urology, University of California-San Francisco, California
| | - Marshall Stoller
- Department of Urology, University of California-San Francisco, California
| | - John Mongan
- Department of Radiology and Biomedical Imaging, University of California-San Francisco, California
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Hein S, Schoenthaler M, Wilhelm K, Schlager D, Vach W, Wetterauer U, Miernik A. Ultralow Radiation Exposure During Flexible Ureteroscopy in Patients With Nephrolithiasis-How Far Can We Go? Urology 2017. [PMID: 28648966 DOI: 10.1016/j.urology.2017.06.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To evaluate the feasibility and clinical performance of a novel surgeon technique and protocol targeting ultralow fluoroscopy usage in retrograde intrarenal surgery (RIRS). MATERIALS AND METHODS All RIRS procedures between 2009 and 2015 for 10- to 20-mm renal calculi performed by the same 2 experienced urologists were eligible. All procedures were performed using a highly standardized step-by-step RIRS technique. This technique was modified by the ultralow radiation exposure RIRS protocol; herein, as much as possible of the standardized steps were performed without radiation control targeting ultralow fluoroscopy usage. Primary end points were fluoroscopy time and dose area product. Secondary end points were stone-free rate (SFR) and intraoperative complications according to Satava classification. End points were evaluated using scatter plots and linear regression model. RESULTS Overall, 174 procedures were assessed. Over the study period, fluoroscopy time and dose area product could be reduced from 167.7 s/318.4 cGy/cm2 in 2009 to 7.4 s/6.4 cGy/cm2 in 2015 (P <.001). SFR (66.7% in 2009; 100% in 2015) and complications (Satava 1 and 2: 28.5% and 4.8%, respectively) improved P <.1), and the surgical duration was reduced (91 minutes and 65 minutes, respectively, P <.001). CONCLUSION Our findings revealed a continuous reduction of the amount of radiation used by the implementation of a novel ultralow X-ray usage protocol. SFR, complications, and surgical duration all improved, demonstrating that the novel protocol is as effective as current methods. Exposure to ionizing radiation can be significantly reduced if the presented protocol is followed strictly.
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Affiliation(s)
- Simon Hein
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| | - Martin Schoenthaler
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Konrad Wilhelm
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Daniel Schlager
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Werner Vach
- Centre for Medical Biometry and Medical Informatics, University of Freiburg, Freiburg, Germany
| | - Ulrich Wetterauer
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Arkadiusz Miernik
- Department of Urology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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The Utility of the Kidneys-ureters-bladder Radiograph as the Sole Imaging Modality and Its Combination With Ultrasonography for the Detection of Renal Stones. Urology 2017; 104:40-44. [DOI: 10.1016/j.urology.2017.03.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/30/2017] [Accepted: 03/09/2017] [Indexed: 11/19/2022]
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Urolithiasis: evaluation, dietary factors, and medical management: an update of the 2014 SIU-ICUD international consultation on stone disease. World J Urol 2017; 35:1331-1340. [DOI: 10.1007/s00345-017-2000-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 01/02/2017] [Indexed: 01/13/2023] Open
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The Diagnosis and Management of Patients with Renal Colic across a Sample of US Hospitals: High CT Utilization Despite Low Rates of Admission and Inpatient Urologic Intervention. PLoS One 2017; 12:e0169160. [PMID: 28046001 PMCID: PMC5207425 DOI: 10.1371/journal.pone.0169160] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 12/13/2016] [Indexed: 11/20/2022] Open
Abstract
Objectives Symptomatic ureterolithiasis (renal colic) is a common Emergency Department (ED) complaint. Variation in practice surrounding the diagnosis and management of suspected renal colic could have substantial implications for both quality and cost of care as well as patient radiation burden. Previous literature has suggested that CT scanning has increased with no improvements in outcome, owing at least partially to the spontaneous passage of kidney stones in the majority of patients. Concerns about the rising medical radiation burden in the US necessitate scrutiny of current practices and viable alternatives. Our objective was to use data from a diverse sample of US EDs to examine rates of and variation in the use of CT scanning, admission, and inpatient procedures for patients with renal colic and analyze the influence of patient and hospital factors on the diagnostic testing and treatment patterns for patients with suspected renal colic. Methods We conducted a retrospective cohort study of adult patients who received a diagnosis of renal colic via a visit to an ED at 444 US hospitals participating in the Premier Healthcare Alliance database from 2009–2011. We modeled use of CT, admission, and inpatient urologic intervention as functions of both patient characteristics and hospital characteristics. Results Over the 2-year period, 307,612 patient visits met inclusion criteria. Among these patients, 254,211 (82.6%) had an abdominal CT scan, with 91.5% being non-contrast (“renal protocol”) CT scans. Nineteen percent of visits (58,266) resulted in admission or transfer, and 9.8% of visits (30,239) resulted in a urologic procedure as part of the index visit. On multivariable analysis male patients, Hispanic patients, uninsured patients, and privately insured patients were more likely to have a CT scan performed. Older patients and those covered by Medicare were more likely to be admitted, and once admitted, white patients and privately insured patients were more likely to have a urologic intervention. Only hospital region was associated with variation in CT rates, and this variation was minimal. Region and size of the hospital were associated with admission rates, and hospitals with more practicing urologists had higher intervention rates. Conclusions In this dataset, the majority of patients did not require admission or immediate intervention. Despite this, the large majority received CT scans, in a cohort representing 15–20% of all US ED visits. The CT rate was minimally variable at the hospital level, but the admission rates varied 2-fold, suggesting that hospital-level factors affect patient management. The high rate of CT usage coupled with the low rate of immediate intervention suggests that further research is warranted to identify patients who are at low risk for an immediate intervention, and could potentially be managed with ultrasound alone, expectant management, or delayed CT.
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Colleran GC, Callahan MJ, Paltiel HJ, Nelson CP, Cilento BG, Baum MA, Chow JS. Imaging in the diagnosis of pediatric urolithiasis. Pediatr Radiol 2017; 47:5-16. [PMID: 27815617 DOI: 10.1007/s00247-016-3702-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 06/28/2016] [Accepted: 09/01/2016] [Indexed: 12/31/2022]
Abstract
Pediatric urolithiasis is an important and increasingly prevalent cause of pediatric morbidity and hospital admission. Ultrasound (US) is the recommended primary imaging modality for suspected urolithiasis in children. There is, however, widespread use of CT as a first-line study for abdominal pain in many institutions involved in pediatric care. The objective of this review is to outline state-of-the-art imaging modalities and methods for diagnosing urolithiasis in children. The pediatric radiologist plays a key role in ensuring that the appropriate imaging modality is performed in the setting of suspected pediatric urolithiasis. Our proposed imaging algorithm starts with US, and describes the optimal technique and indications for the use of CT. We emphasize the importance of improved communication with a greater collaborative approach between pediatric and general radiology departments so children undergo the appropriate imaging evaluation.
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Affiliation(s)
- Gabrielle C Colleran
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02116, USA.
| | - Michael J Callahan
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02116, USA
| | - Harriet J Paltiel
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02116, USA
| | - Caleb P Nelson
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
| | | | - Michelle A Baum
- Department of Nephrology, Boston Children's Hospital, Boston, MA, USA
| | - Jeanne S Chow
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02116, USA
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Hudnall M, Usawachintachit M, Metzler I, Tzou DT, Harrison B, Lobo E, Chi T. Ultrasound Guidance Reduces Percutaneous Nephrolithotomy Cost Compared to Fluoroscopy. Urology 2016; 103:52-58. [PMID: 28024969 DOI: 10.1016/j.urology.2016.12.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 11/03/2016] [Accepted: 12/16/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To examine the cost factors associated with ultrasound and fluoroscopic guidance for percutaneous nephrolithotomy (PCNL) and to determine which method can be performed at a lower cost per case. METHODS A cost comparison study was performed utilizing clinical data from a prospectively maintained research database. We included the most recent 33 consecutive ultrasound-guided PCNL cases in 2016 and the most recent 40 consecutive fluoroscopy-guided PCNL cases before the operative surgeon transitioned to ultrasound guidance in May 2014. The total operative time and clinical outcomes were examined. Costs were extracted from the institution accounting systems and given a uniform multiplier to protect institutional financial reporting confidentiality. Comparisons were made using the Student t test and the chi-squared test. RESULTS After excluding outliers, 71 PCNL procedures were included in the analysis. Demographic data and stone characteristics were not different between ultrasound-guided and fluoroscopy-guided groups. However, the mean operative time for ultrasound-guided PCNL was significantly shorter (99.8 ± 27.0 vs 144.9 ± 55.1 minutes, P < .05). When capital equipment costs were included, the mean total cost per case of ultrasound-guided PCNL was approximately 30% less than fluoroscopy-guided PCNL (simulated costs with a uniform multiplier; $5258.90 ± 957.12 vs $7508.60 ± 1163.83, P < .05). Postoperative clinical outcomes were comparable between the 2 groups. CONCLUSION When capital costs are included, ultrasound-guided PCNL can produce comparable clinical outcomes to fluoroscopy-guided procedures at a lower cost to the institution. Shorter operative time drives significant savings with the adoption of ultrasound guidance, which may be magnified with increasing case volume. Using ultrasound imaging during PCNL may be more cost-effective compared to fluoroscopy and warrants further study.
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Affiliation(s)
- Matthew Hudnall
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Manint Usawachintachit
- Department of Urology, University of California, San Francisco, San Francisco, CA; Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Chulalongkorn University, Bangkok, Thailand
| | - Ian Metzler
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - David T Tzou
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Brittany Harrison
- Department of Urology, University of California, San Francisco, San Francisco, CA
| | - Errol Lobo
- Department of Anesthesia, University of California, San Francisco, San Francisco, CA
| | - Thomas Chi
- Department of Urology, University of California, San Francisco, San Francisco, CA.
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Assimos DG. Re: Pulsed versus Continuous Mode Fluoroscopy during PCNL: Safety and Effectiveness Comparison in a Case Series Study. J Urol 2016; 197:172. [PMID: 27979530 DOI: 10.1016/j.juro.2016.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Horsburgh BA, Higgins M. A Study of Occupational Radiation Dosimetry During Fluoroscopically Guided Simulated Urological Surgery in the Lithotomy Position. J Endourol 2016; 30:1312-1320. [DOI: 10.1089/end.2016.0596] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Ben A. Horsburgh
- Department of Urology, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, United Kingdom
| | - Mike Higgins
- Diagnostic Radiation Protection, Integrated Radiological Services (IRS) Limited, Liverpool, United Kingdom
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Cochon L, Smith J, Baez AA. Bayesian comparative assessment of diagnostic accuracy of low-dose CT scan and ultrasonography in the diagnosis of urolithiasis after the application of the STONE score. Emerg Radiol 2016; 24:177-182. [PMID: 27885441 DOI: 10.1007/s10140-016-1471-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/16/2016] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective of our study was to assess the diagnostic quality of low-dose computed tomography (CT) when compared to ultrasound (US) in diagnosis of urolithiasis using STONE score as a predictor of pre-test probability and the Bayesian statistical model to calculate post-test probabilities (POST) for both diagnostic tests. METHODS STONE score was used to form risk groups to obtain pre-test probabilities. Likelihood ratios (LR) were calculated from external data for low-dose CT and US. POST were obtained using pre-test probabilities and likelihood ratios with Bayesian nomogram. Absolute (ADG) and relative (RDG) gains in diagnostic value were calculated. RESULTS Calculated +LR for US was 12 and -LR was 0.32; for CT, +LR was 19 and -LR 0.04. +LR and low STONE for US yielded POST 57% and RDG 470%; intermediate STONE POST 92% and RDG 84%; and high STONE POST 99% and RDG 10%. -LR and low STONE for US POST 3% and RDG -70%; intermediate POST 24% and RDG -52%; and high STONE POST 74% and RDG -17.7%. +LR and low STONE for CT POST 68% and RDG 580%; moderate STONE POST 95% and RDG 90%; and high STONE POST 99% and RDG 10%. -LR and low STONE for CT POST 0% and RDG -100%; intermediate POST 4% and RDG -92%; and high STONE POST 26% and RDG -71.1%. ANOVA calculations comparing CT vs US for +LR showed no statistical significance (P value = 0.9893; LR- P value = 0.5488). CONCLUSION Bayesian statistical analysis demonstrated slight superiority of CT scan over US on STONE score low- and moderate-risk stratified subtypes, whereas no significant advantage was seen when evaluating high-probability patients.
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Affiliation(s)
| | - Jeffrey Smith
- Miller School of Medicine, University of Miami, Miami, FL, USA
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Akhavein A, Ganesan V, Tarplin S, Monga M, Sivalingam S. Urolithiasis and Frequent CT Scans: Does Chronic Pain Play a Role? J Endourol 2016; 30:1161-1164. [DOI: 10.1089/end.2016.0204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Arash Akhavein
- Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Vishnu Ganesan
- Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Sarah Tarplin
- Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Manoj Monga
- Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Sri Sivalingam
- Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
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Chi T, Usawachintachit M, Mongan J, Kohi MP, Taylor A, Jha P, Chang HC, Stoller M, Goldstein R, Weinstein S. Feasibility of Antegrade Contrast-enhanced US Nephrostograms to Evaluate Ureteral Patency. Radiology 2016; 283:273-279. [PMID: 28234551 DOI: 10.1148/radiol.2016160959] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Purpose To demonstrate the feasibility of contrast material-enhanced ulrasonographic (US) nephrostograms to assess ureteral patency after percutaneous nephrolithotomy (PCNL) in this proof-of-concept study. Materials and Methods For this HIPAA-compliant, institutional review board-approved prospective blinded pilot study, patients undergoing PCNL provided consent to undergo contrast-enhanced US and fluoroscopic nephrostograms on postoperative day 1. For contrast-enhanced US, 1.5 mL of Optison (GE Healthcare, Oslo, Norway) microbubble contrast agent solution (perflutren protein-type A microspheres) was injected via the nephrostomy tube. Unobstructed antegrade ureteral flow was defined by the presence of contrast material in the bladder. Contrast-enhanced US results were compared against those of fluoroscopic nephrostograms for concordance. Results Ten studies were performed in nine patients (four women, five men). Contrast-enhanced US demonstrated ureteral patency in eight studies and obstruction in two. One patient underwent two studies, one showing obstruction and the second showing patency. Concordance between US and fluoroscopic assessments of ureteral patency was evaluated by using a Clopper-Pearson exact binomial test. These results were perfectly concordant with fluoroscopic nephrostogram results, with a 95% confidence interval of 69.2% and 100%. No complications or adverse events related to contrast-enhanced US occurred. Conclusion Contrast-enhanced US nephrostograms are simple to perform and are capable of demonstrating both patency and obstruction of the ureter. The perfect concordance with fluoroscopic results across 10 studies demonstrated here is not sufficient to establish diagnostic accuracy of this technique, but motivates further, larger scale investigation. If subsequent larger studies confirm these preliminary results, contrast-enhanced US may provide a safer, more convenient way to evaluate ureteral patency than fluoroscopy. © RSNA, 2016 Online supplemental material is available for this article.
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Affiliation(s)
- Thomas Chi
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Manint Usawachintachit
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - John Mongan
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Maureen P Kohi
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Andrew Taylor
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Priyanka Jha
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Helena C Chang
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Marshall Stoller
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Ruth Goldstein
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
| | - Stefanie Weinstein
- From the Departments of Urology (T.C., M.U., H.C.C., M.S.) and Radiology and Biomedical Imaging (J.M., M.P.K., A.T., P.J., R.G., S.W.), University of California, San Francisco. 505 Parnassus Ave, M-391, San Francisco, CA 94143; and Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, The Thai Red Cross Society, Bangkok, Thailand (M.U.)
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Usawachintachit M, Masic S, Allen IE, Li J, Chi T. Adopting Ultrasound Guidance for Prone Percutaneous Nephrolithotomy: Evaluating the Learning Curve for the Experienced Surgeon. J Endourol 2016; 30:856-63. [PMID: 27150671 DOI: 10.1089/end.2016.0241] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To define the learning curve associated with adopting ultrasound guidance for prone percutaneous nephrolithotomy (PCNL) for the experienced surgeon. METHODS A prospective cohort study of consecutive patients undergoing PCNL with ultrasound guidance for renal tract access and dilation was performed. Clinical data reviewed included success in gaining renal access with ultrasound guidance, total fluoroscopic screening time, and radiation exposure dose. PCNL cases performed with fluoroscopic guidance matched for stone size served as control cases. RESULTS One hundred consecutive ultrasound-guided procedures performed by a single experienced endourologist were divided into five experience groups. Significant improvement in renal access success rate with ultrasound was seen after 20 cases (p < 0.05). Total fluoroscopic screening time, radiation exposure dose, and operative time were also statistically significantly improved over the study period. When compared with fluoroscopy-guided PCNL, significant decreases in total fluoroscopic screening time (33.4 ± 35.3 seconds vs 157.5 ± 84.9 seconds, p < 0.05) and radiation exposure (7.0 ± 8.7 mGy vs 47.8 ± 45.9 mGy, p < 0.05) were seen. No differences in complication rates were found. CONCLUSIONS Ultrasound-guided renal access for PCNL can be performed effectively after 20 cases. Transition to the use of ultrasound will quickly reduce radiation exposure for patients and intraoperative personnel.
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Affiliation(s)
- Manint Usawachintachit
- 1 Department of Urology, University of California , San Francisco, San Francisco, California.,2 Division of Urology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Chulalongkorn University , Bangkok, Thailand
| | - Selma Masic
- 1 Department of Urology, University of California , San Francisco, San Francisco, California
| | - Isabel E Allen
- 3 Department of Epidemiology and Biostatistics, University of California , San Francisco, San Francisco, California
| | - Jianxing Li
- 4 Department of Urology, Tsinghua Changgung Hospital , Beijing, China
| | - Thomas Chi
- 1 Department of Urology, University of California , San Francisco, San Francisco, California
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Young BJ, Tejwani R, Wang HHS, Wolf S, Purves JT, Wiener JS, Routh JC. Is the Economic Impact and Utilization of Imaging Studies for Pediatric Urolithiasis Across the United States Increasing? Urology 2016; 94:208-13. [PMID: 27208819 DOI: 10.1016/j.urology.2016.05.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/05/2016] [Accepted: 05/10/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To identify longitudinal trends of economic impact and resource utilization for management of pediatric urolithiasis using national databases. METHODS We analyzed the 2006-2012 Nationwide Emergency Department Sample and Nationwide Inpatient Sample. We used ICD-9 (International Classification of Diseases) codes to identify patients (≤18 years) diagnosed with urolithiasis. Diagnostic imaging and surgeries were identified using ICD-9 and Current Procedural Technology codes. We abstracted demographic, imaging, procedure, and charge data. Weighted descriptive statistics were calculated to describe the population's demographics and economic expenditures by clinical setting and year. RESULTS In total, 45,333 inpatient admissions (68% females) and 234,559 emergency department encounters (63% females) were identified. Most patients (84%) were teenagers and the southern region of the United States was the most common geographic region for all encounters (44%). There was no significant trend in number of urolithiasis encounters over the period studied. Utilization of all imaging techniques increased; in particular, computed tomography was used in 23% of encounters in 2006 and 40% in 2012 (P < .0001). The mean charge per emergency department visit increased by 60% from $3645 in 2006 to $5827 in 2012 (P < .0001). The mean charge increased for inpatient admissions by 102%, from $16,399 in 2006 to $33,205 in 2012 (P < .0001). Total charges increased 72% over the study period from $230 million in 2006 to $395 million in 2012 (P < .0001), outpacing medical inflation over the same period. CONCLUSION Charges for pediatric urolithiasis management increased by 65% from 2006 to 2012 despite stable frequency of patient encounters. The utilization of computerized tomography in pediatric urolithiasis increased as well.
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Affiliation(s)
- Brian J Young
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC
| | - Rohit Tejwani
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC
| | - Hsin-Hsiao S Wang
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC
| | - Steven Wolf
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC
| | - J Todd Purves
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC
| | - John S Wiener
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC
| | - Jonathan C Routh
- Division of Urologic Surgery, Duke University Medical Center, Durham, NC.
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