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Urologiia 2018 Oct(4):154-160

I.M. Sechenov First MSMU of Minzdrav of Russia, Moscow, Russia.

The article presents pooled results of domestic and international studies investigating genetic aspects of urolithiasis associated with impaired calcium metabolism. The review highlights the importance of early and accurate diagnosis of hereditary diseases associated with kidney stone formation. Of more than 80 currently known monogenic forms of urolithiasis, the authors provide the list of the most significant forms. Read More

Urologiia 2018 Oct(4):96-101

N.A. Lopatkin Scientific Research Institute of Urology and Interventional Radiology branch of the NMRRC of Minzdrav of Russia, Moscow, Russia.

Aim: To compare the results of a single tract versus multi-tract percutaneous nephrolithotomy (PNL) MATERIALS AND METHODS: Over a period of 6 years, a total of 2,264 PNLs was performed at the N.A. Lopatkin Scientific Research Institute of Urology and Interventional Radiology, of which 875 PNLs were done for stage K3-K4 staghorn calculi. Read More

J Nephrol 2019 Jan 24. Epub 2019 Jan 24.

Department of Internal Medicine, and Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.

A symposium on kidney stones and mineral metabolism held on December 2017 in Brussels, Belgium was the first international multidisciplinary conference of the International Collaborative Network on Kidney Stones and Mineral Metabolism. This meeting addressed epidemiology, underlying pathophysiological mechanisms, genetics, pathological, as well as clinical and research topics. The participants included clinicians and recognized experts in the field from Europe and the United States interacted closely during the symposium which promoted a chance to explore new frontiers in the field of kidney stone disease. Read More

Urolithiasis 2019 Feb 23;47(1):35-42. Epub 2019 Jan 23.

Royal Free Hospital/Medical School, Centre for Nephrology, University College London, London, NW3 2PF, UK.

The proximal tubule is responsible for reclaiming water, phosphates and amino acids from the tubular filtrate. There are genetic defects in both phosphate and amino acid transporters leading to nephrolithiasis. This review also explores genetic defects in regulators of phosphate and calcium transport in this nephron segment that lead to stone formation. Read More

Nihon Hinyokika Gakkai Zasshi 2018 ;109(1):54-57

The Department of Urology, Osaka Police Hospital.

We report a case of lithiasis of the left ectopic pelvic kidney. A 70-year-old man was admitted to our department for left lower back pain. He has been aware of gross hematuria since three or four years before. Read More

Nihon Hinyokika Gakkai Zasshi 2018 ;109(1):50-53

Department of Urology, Toyohashi Municipal Hospital.

A 77-year-old man with a right kidney stone was admitted to our hospital. A ureteroscope was introduced into the ureter without dilation under direct vision. We then performed flexible transurethral lithotripsy (f-TUL) using a ureteral access sheath and successfully fragmented the stone and extracted almost all the stone fragments without any complications. Read More

J Urol 2019 02;201(2):356-357

CDC Zdorovie, Rostov-on-Don, Russia.

J Urol 2019 02;201(2):356

Department of Urology, Vanderbilt University Medical Center, Nashville, Tennessee.

J Urol 2019 02;201(2):224

J Urol 2019 02;201(2):223

Pediatr Nephrol 2019 Jan 4. Epub 2019 Jan 4.

Department of Pediatrics, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada.

Background: The incidence of nephrolithiasis in children and adolescents is increasing and appears to double every 10 years. The most important role of the pediatric nephrologist is to diagnose and modify various metabolic and non-metabolic risk factors, as well as prevent long-term complications especially in the case of recurrent nephrolithiasis.

Objective: The purpose of this review is to summarize the existing literature on the etiology and management of pediatric nephrolithiasis. Read More

Free Radic Biol Med 2018 Dec 29;134:9-22. Epub 2018 Dec 29.

Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.

Hyperoxaluria induces oxidative stress, and inflammation causes renal epithelial cell injury in nephrolithiasis, suggesting that reduced oxalate toxicity may be beneficial. This study aimed to investigate whether nuclear factor (erythroid-derived 2)-like 2 (Nrf2, also called Nfe2l2) induced by dimethyl fumarate (DMF) could protect renal epithelial cells against oxalate-mediated injury both in vivo and in vitro. Glyoxylic acid monohydrate was intraperitoneally injected into Sprague-Dawley rats with or without intragastric administration of DMF. Read More

Drug Healthc Patient Saf 2018 12;10:103-108. Epub 2018 Dec 12.

Infectious Disease Research Center, Birjand University of Medical Sciences, Birjand, Iran,

Background: Ceftriaxone (CTX) is widely used for the treatment of bacterial infections; however, side effects such as gallstone and nephrolithiasis have been reported in children. There is limited information about urinary tract calculi as CTX side effects in adults. Therefore, the present study was aimed to evaluate the incidence of gallstone and nephrolithiasis following CTX administration. Read More

J Urol 2019 01;201(1):187-188

Service d'Urologie, Hôpital Tenon, Assistance publique-Hôpitaux de Paris, Groupe de Recherche Clinique sur la Lithiase Urinaire, Sorbonne Université, Paris, France.

J Urol 2019 01;201(1):24-25

J Urol 2019 01;201(1):24

Transplant Proc 2018 Dec 29;50(10):3950-3953. Epub 2018 May 29.

Kidney Transplantation, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy; Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy. Electronic address:

Increasing demand drives the expansion of criteria for kidney donation, and nephrolithiasis is now considered a relative contraindication. We report for the first time a case of intra-operative, postperfusion kidney allograft micronephrolithotomy. A 64-year-old man with end-stage renal disease secondary to Alport syndrome underwent primary deceased donor kidney transplantation at our center. Read More

Urologiia 2018 Dec(5):122-127

FGAOU VO I.M. Sechenov First Moscow State Medical University, Moscow, Russia.

Disturbances of vitamin D metabolism is one of the factors leading to the impairment of phosphate and calcium homeostasis which plays leading role in the development of urinary stone disease. Vitamin D is necessary for wide spectrum of physiologic processes and good health condition. Until now, in many guidelines on urolithiasis there is an advice to limit vitamin D intake due to concerns of an increase in the stone formation. Read More

Urologiia 2018 Dec(5):74-80

Research Institute of Uronephrology and Human Reproductive Health, Department and Clinic of Urology, I.M. Sechenov First MSMU, Moscow, Russia.

Aim: Experimental evaluation of the efficacy and safety of lithotripsy using a new pulsed thulium fiber laser operating at a wavelength of 1.94 microns, peak power of 500 watts (maximum average power of 50 watts) by comparing it with a holmium laser operating at a wavelength of 2.1 microns (average maximum power 100 W and 120 W). Read More

Clin Interv Aging 2018 28;13:2443-2452. Epub 2018 Nov 28.

Center for Bioinformatics and Genomics, Department of Global Biostatistics and Data Science, Tulane University, New Orleans, LA 70112, USA,

Calcium is an important integrative component of the human body and critical for human health. It has been well established that calcium intake is helpful in the prevention and treatment of osteoporosis, which has become one of the most serious public health problems across the world. However, community-dwelling adults with and without osteoporosis are rarely concerned or even not aware of the potential side effects of high or inappropriate doses of calcium intake. Read More

Urolithiasis 2019 Feb 18;47(1):91-98. Epub 2018 Dec 18.

Chair of Nephrology, Department of Translational Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy.

In the last decades, proteomics has been largely applied to the Nephrology field, with the double aim to (1) elucidate the biological processes underlying renal diseases; (2) identify disease-specific biomarkers, predictor factors of therapeutic efficacy and prognostic factors of disease progression. Kidney stone disease, and in particular, inherited nephrolithiasis (INL) are not an exception. Given the multifactorial origin of these disorders, the combination of genomics and proteomics studies may complement each other, with the final objective to give a global and comprehensive mechanistic view. Read More

J Clin Exp Hepatol 2018 Dec 11;8(4):375-379. Epub 2018 Feb 11.

Division of Nephrology & Hypertension, Mayo Clinic, Jacksonville, FL, United States.

Background And Aims: Nephrolithiasis is known to be associated with several systemic diseases including chronic kidney disease and renal failure, which can also occur as a complication of chronic liver disease (CLD). This study aimed to assess the prevalence of nephrolithiasis in patients with CLD.

Methods: A short survey was completed by 198 patients with CLD and 322 controls matched by age, sex, and state of residence. Read More

Acta Biomed 2018 Dec 17;89(9-S):76-80. Epub 2018 Dec 17.

Pediatric Emergency Unit, University Hospital of Parma, Maternal and Infant Department, Parma, Italy.

Background And Aim Of The Work: Historical studies have demonstrated that the prevalence of symptomatic nephrolithiasis is higher in patients with inflammatory bowel disease (IBD), compared to general population. The aim of the review was to analyze literature data in order to identify the main risk conditions described in literature and the proposed treatment.

Methods: A research on the databases PubMed, Medline, Embase and Google Scholar was performed by using the keywords "renal calculi/lithiasis/stones" and "inflammatory bowel diseases". Read More

Urolithiasis 2019 Feb 6;47(1):11-21. Epub 2018 Dec 6.

Department of Statistics, deCODE genetics, Reykjavik, Iceland.

Kidney stone disease is a common disorder in Western countries that is associated with significant suffering, morbidity, and cost for the healthcare system. Numerous studies have demonstrated familial aggregation of nephrolithiasis and a twin study estimated the heritability to be 56%. Over the past decade, genome-wide association studies have uncovered several sequence variants that confer increased risk of common complex kidney stone disease. Read More

Urolithiasis 2019 Feb 10;47(1):79-89. Epub 2018 Dec 10.

Mayo Clinic, Rochester, MN, USA.

Primary hyperoxaluria (PH) is caused by genetic mutations resulting in oxalate overproduction leading to nephrolithiasis, nephrocalcinosis, extrarenal manifestations, chronic kidney disease, and end-stage renal disease. Advances in genetic testing techniques have improved our ability to efficiently and effectively obtain a definitive diagnosis of PH as well as easily screen at-risk family members. Similarly, advances in technologies related to intervening at the genetic and molecular level promise to change the way we treat patients with PH. Read More

Front Pediatr 2018 16;6:353. Epub 2018 Nov 16.

Scott Department of Urology, Baylor College of Medicine, Houston, TX, United States.

While small non-obstructive stones in the adult population are usually observed with minimal follow-up, the same guidelines for management in the pediatric population have not been well-studied. We evaluate the clinical outcomes of small non-obstructing kidney stones in the pediatric population to better define the natural history of the disease. In this IRB-approved retrospective study, patients with a diagnosis of kidney stones from January 2011 to March 2017 were identified using ICD9 and ICD10 codes. Read More

Ulus Travma Acil Cerrahi Derg 2018 Nov;24(6):514-520

Sorbonne Université, GRC n°20 LITHIASE RENALE, AP-HP, Hôpital Tenon, Paris-France.

Background: Ureteral access sheaths (UASs) are commonly used in retrograde intra-renal surgery (RIRS). Despite their advantages, there is a risk of ureteral trauma during their placement and subsequent stricture following surgery. The aim of this study was to evaluate the UAS force of insertion (FOI) during placement and its impact on ureteral trauma. Read More

Int J Rheum Dis 2018 Nov 28. Epub 2018 Nov 28.

Department of Internal Medicine, Midorigaoka Hospital, Takatsuki-shi, Japan.

Objective: To clarify the clinical and laboratory characteristics of nephrolithiasis in gout by computed tomography (CT).

Methods: In 350 gout patients, unenhanced CT was performed at the 1st visit to hospital. Calculus density spots exceeding 1 mm in diameter with a CT value >120 Hounsfield units in the kidneys were defined as kidney stones. Read More

Urol Int 2018 Nov 27:1-7. Epub 2018 Nov 27.

Department of Urology, St. Elisabeth Hospital, Straubing, Germany.

Background: The Post-Ureteroscopic Lesion Scale (PULS) is a validated, standardised scale that classifies iatrogenic ureteral lesions during ureteroscopy (URS).

Objective: To determine risk factors for the various PULS-grades caused by URS.

Method: We prospectively investigated the independent influence of various risk factors in correlation with PULS-Grade 1+ and 2+ on 307 patients with ureterorenoscopic stone treatment from 14 German urologic departments. Read More

Urolithiasis 2019 Feb 26;47(1):107-113. Epub 2018 Nov 26.

Nephrology Division, NYU Langone Health, New York, NY, USA.

Careful phenotyping of patients to classify those with kidney stones has a long and important history in revealing the chemical basis for stone formation. Advances in our genetic understanding of kidney stones will lead to incredible insights regarding the pathophysiology of this common disorder. At this time, both evaluation of urine chemistry and genotyping of patients are extremely useful in the setting of a university and research-based kidney stone clinic. Read More

Nutrition 2019 Mar 22;59:83-89. Epub 2018 Aug 22.

Kidney Stone Clinic, Medical-Geriatric-Rehabilitation Department, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy; Department of Medicine and Surgery, University of Parma, Parma, Italy.

Objectives: Urinary hippuric acid (HA) and citrate can represent useful biomarkers of fruit and vegetable (FAV) intake in nephrolithiasis. However, their clinical significance across the life span has been poorly investigated. The aim of this study was to investigate the association between the two biomarkers with FAV intake across different age groups and sexes in a large group of stone formers (SFs). Read More

Urolithiasis 2019 Feb 23;47(1):115-123. Epub 2018 Nov 23.

UOC Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.

Deciding whether to accept a donor with nephrolithiasis is a multifaceted task because of the challenge of finding enough suitable donors while at the same time ensuring the safety of both donors and recipients. Until not long ago, donors with a history of renal stones or with stones emerging during screening on imaging were not considered ideal, but recent guidelines have adopted less stringent criteria for potential donors at risk of stones. This review goes through the problems that need to be approached to arrive at a wise clinical decision, balancing the safety of donors and recipients with the need to expand the organ pool. Read More

J Ayub Med Coll Abbottabad 2018 Jul-Sep;30(3):470-472

Aga Khan University, Pakistan.

Extracorporeal shock wave lithotripsy (ESWL) is among the most widely used modalities for treatment of urolithiasis since its introduction in the 1980s. The non-invasive technique reduces the risk of post-procedure complications and produces excellent stone free rates. However, complications may still follow and albeit rare, there are reports in literature of abscess formation post ESWL. Read More

Medicine (Baltimore) 2018 Nov;97(47):e13314

Department of Urology, The Second Affiliated Hospital of Zhejiang University School of Medicine.

Background: The aim of this study was to provide a randomized controlled trial comparing single B-mode ultrasound guidance and color doppler ultrasound guidance in minimally invasive percutaneous nephrolithotomy.

Methods: Three hundred patients with renal calculus were prospectively randomly assigned into 2 groups. In group 1 (150 patients), minimally invasive percutaneous nephrolithotomy (m-PCNL) were managed with single B-mode ultrasound guidance; In group 2 (150 patients), m-PCNL were managed with color Doppler ultrasound guidance and a needle bracket in order to guide placement at a target location beneath the skin. Read More

Urolithiasis 2019 Feb 20;47(1):43-56. Epub 2018 Nov 20.

Division of Nephrology and Hypertension, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 15, 3010, Bern, Switzerland.

Twin and genealogy studies suggest a strong genetic component of nephrolithiasis. Likewise, urinary traits associated with renal stone formation were found to be highly heritable, even after adjustment for demographic, anthropometric and dietary covariates. Recent high-throughput sequencing projects of phenotypically well-defined cohorts of stone formers and large genome-wide association studies led to the discovery of many new genes associated with kidney stones. Read More

Urolithiasis 2019 Feb 20;47(1):99-105. Epub 2018 Nov 20.

Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle, NE1 3BZ, UK.

Here we define precision medicine approaches and discuss how these may be applied to renal stone-formers to optimise diagnosis and a management. Using the gene discovery of monogenic stone disorders as examples, we discuss the benefits of personalising therapies for renal stone-formers to provide improved prevention and treatment of these disorders. Read More

Urolithiasis 2019 Feb 20;47(1):5-10. Epub 2018 Nov 20.

Genomic Medicine Institute, Department of Nephrology and Hypertension, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.

Urinary stones tend to cluster in families. Of the known risk factors, evidence is strongest for heritability of urinary calcium excretion. Recent studies suggest that other stone risk factors may have heritable components including urinary pH, citrate and magnesium excretion, and circulating vitamin D concentration. Read More

Urolithiasis 2019 Feb 16;47(1):23-33. Epub 2018 Nov 16.

Nephrology and Dialysis Unit, Postgraduate School of Nephrology, IRCCS San Raffaele Scientific Institute, Vita Salute University, 20132, Milan, Italy.

Calcium-sensing receptor (CaSR) is a plasma-membrane G protein-coupled receptor activated by extracellular calcium and expressed in kidney tubular cells. It inhibits calcium reabsorption in the ascending limb and distal convoluted tubule when stimulated by the increase of serum calcium levels; therefore, these tubular segments are enabled by CaSR to play a substantial role in the regulation of serum calcium levels. In addition, CaSR increases water and proton excretion in the collecting duct and promotes phosphate reabsorption and citrate excretion in the proximal tubule. Read More

Medicine (Baltimore) 2018 Nov;97(45):e13037

Department of Urology, Yangzhou No.1 People's Hospital, Yangzhou.

The objective of this study is to find about the association between calcium-sensing receptor (CaSR) genetic variants and susceptibility to nephrolithiasis in the Chinese Han population.This hospital-based case-control study included 319 nephrolithiasis cases and 378 healthy controls subjects. Two SNPs in CaSR were genotyped using the TaqMan assay. Read More

Arch Esp Urol 2018 Nov;71(9):772-781

Department of Urology. Kecioren Research and Training Hospital. Ankara. Turkey.

Introduction: Fluoroscopy is used for access sheath insertion and postoperative control during retrograde intrarenal surgery (RIRS) operation but with this technique both patient and operation team are exposed to radiation. The use of fluoroscopy is disadvantage for both patient and surgeon. Considering results of recent studies, it is clearly seen that fluoroscopy doesn't affect the success and complication rates of RIRS. Read More

Arch Esp Urol 2018 Nov;71(9):765-771

Servicio de Urología. Hospital Universitario Virgen del Rocío. Sevilla. España.

Objective: To evaluate patient compliance with treatment for urinary lithiasis and to detect differences in adherence, causes of this behavior and associated factors.

Methods: We performed a retrospective study of 93 patients with positive urinary metabolic study (UMS) for lithogenic pathology, diagnosed between 2013 and 2015, gathering data from the digital medical records and a structured telephonic questionnaire in 75 of them. Results were analyzed using the X2 test. Read More

Ren Fail 2018 Nov;40(1):618-627

a The Emergency Center, Gansu Nephro-Urological Clinical Center, Lanzhou University Second Hospital , Lanzhou China.

Purpose: To evaluate a Angelica sinensis polysaccharide aqueous extract as a preventive agent in experimentally induced urolithiasis using in- vitro and vivo models.

Material And Methods: Angelica sinensis polysaccharide was investigated in vitro to determine its antilithiatic effects on the formation and morphology of calcium oxalate (CaOx) crystals and was analyzed in vivo to determine its ability to prevent CaOx urolithiasis in rats subjected to ethylene glycol-induced urolithiasis. Potassium citrate administration was used in the positive control group. Read More

Saudi J Kidney Dis Transpl 2018 Sep-Oct;29(5):1203-1206

Department of Pediatric Nephrology, Sheikh Khalifa Medical City, Abu Dhabi, UAE.

The incidence of urolithiasis in children has shown an increase in recent years which may be attributed to changing dietary patterns, sedentary lifestyles, and obesity. Among the various etiologies for renal stones in children, two rare entities worth mentioning are cystinuria and 2, 8-dihydroxyadenine (DHA) urolithiasis. Cystinuria is an inherited cause of nephrolithiasis which occurs due to impaired cystine reabsorption in the renal proximal tubule. Read More

Luminescence 2018 Dec 31;33(8):1438-1444. Epub 2018 Oct 31.

CSIC. Museo Nacional de Ciencias Naturales, C/José Gutiérrez Abascal 2, Madrid, Spain.

The radiation effect of luminescence emission of Ca-rich oxalate biogenic materials (gallbladder and renal calculi) and a commercial standard sample (CaC O ·H O) is reported. The samples were characterized by environmental scanning electron microscopy, energy dispersive X-ray spectroscopy, thermogravimetric and differential thermal analyses, display complex cathodoluminescence (CL) and thermoluminescence (TL) glow emissions. CL spectra (in the UV-infrared range) displayed non-well defined peaks, and exhibited emission at: (i) higher energies (300-490 nm) mainly associated with non-bridging oxygen hole centers, oxygen-deficient centers and peroxy intrinsic defects, regardless of the sample; and (ii) higher, narrow and sharp wavebands, in the red region, probably induced by the presence of traces of Sm ( G → H transition) and/or Tb ( D → F transition) only for mineral-like materials in the human body. Read More

J Coll Physicians Surg Pak 2018 Nov;28(11):858-861

Department of Urology, The Kidney Centre, Postgraduate Training Institute, Karachi, Pakistan.

Objective: To compare postoperative mean pain score of bupivacaine versus placebo in patients undergoing percutaneous nephrolithotomy.

Study Design: An experimental study.

Place And Duration Of Study: Department of Urology, The Kidney Centre, Postgraduate Training Institute (PGTI), Karachi, from November 2014 to December 2015. Read More

Urolithiasis 2018 Oct 27. Epub 2018 Oct 27.

Department of Urology, Loyola University Medical Center, Maywood, IL, 60153, USA.

Antepartum nephrolithiasis presents a complex clinical scenario which often requires an intervention such as ureteral stent or percutaneous nephrostomy tube (PCNT) placement, especially in the setting of urinary tract infection (UTI). We assess the risk of UTI and preterm labor in the setting of antepartum nephrolithiasis. A retrospective review of an administrative dataset for California and Florida was performed, which included pregnant women admitted for a delivery between 2008 and 2011. Read More

Asian J Urol 2018 Oct 4;5(4):256-263. Epub 2018 Sep 4.

Division of Urology, St. Michael's Hospital, Toronto, Canada.

For over 35 years shock wave lithotripsy has proven to be an effective, safe and truly minimally invasive option for the treatment of nephrolithiasis. Various technical factors as well as patient selection can impact the success of the procedure. We used published work focusing on outcomes of shock wave lithotripsy, risk of complications, and strategies for improving stone fragmentation to create this review. Read More

Asian J Urol 2018 Oct 26;5(4):235-242. Epub 2018 Jun 26.

Universidade Federal de São Paulo, Nephrology Division, São Paulo, Brazil.

Considering the variation in metabolic evaluation and medical management of kidney stone disease, this consensus review was created to discuss the metabolic activity of nephrolithiasis, define the difference between single and recurrent stone formers, and develop a schema for metabolic and radiologic follow-up. A systematic review of the literature was performed to identify studies of metabolic evaluation and follow-up of patients with nephrolithiasis. Both single and recurrent stone formers share many similarities in metabolic profiles. Read More

Asian J Urol 2018 Oct 8;5(4):215-222. Epub 2018 Jun 8.

Department of Urology, University of Alabama-Birmingham, Birmingham, AL, USA.

The prevalence of kidney stone disease is increasing, afflicting 7%-11% of the United States population. Multiple systemic conditions, including obesity and diabetes, are also on the rise. Further, the literature has demonstrated a strong association between metabolic syndrome, its components, and kidney stone disease. Read More

Biomed Res Int 2018 27;2018:5120974. Epub 2018 Sep 27.

Department of Urology, University of Florida, Gainesville, FL, USA.

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. Read More