Purpose: To preoperatively assess the composition of urinary stones by using dual-energy computed tomography (CT), with postoperative in vitro x-ray diffraction analysis as the reference standard. Materials and Methods: Institutional review board approval was obtained, and all participants provided written informed consent. Twenty-seven patients aged 50-64 years with renal stones, ...

OBJECTIVES: To evaluate the ability of noncontrast computed tomography (NCCT) to predict stone composition and fragility for treatment with extracorporeal shock wave lithotripsy (SWL). METHODS: A total of 103 stones from patients who had undergone different open surgical procedures were scanned with a 64 detector row helical computed tomography (CT) ...

OBJECTIVES: To evaluate differences in stone measurement using computed tomography (CT) and ultrasound (US). Axial unenhanced helical CT is the reference-standard imaging modality for the assessment of urinary tract calculi; however, US is also commonly used. Differences in stone measurement using these techniques are poorly described and contributors to measurement ...

Urinary tract stone disease is common in the Western world. Nonenhanced computed tomography (CT) is the method of choice for stone diagnosis; however, it has a limited role in predicting stone type. Knowledge of stone composition is currently determined by postoperative assessment of stone fragments. A noninvasive tool for accurate ...

AIMS: To compare in vivo DNA lesions induced during helical and sequential coronary computed tomography angiography (CTA) and to evaluate the effect of CT parameters on double-strand break (DSB) levels. METHODS: Thirty-six patients were examined with various CT protocols and modes (helical scan, n = 27; sequential scan, n = ...

PURPOSE: The potential of dual energy computed tomography (DECT) for the analysis of gallstone compounds was investigated. The main goal was to find parameters, that can reliably define high percentage (>70%) cholesterol stones without calcium components. MATERIALS AND METHODS: 35 gallstones were analyzed with DECT using a phantom model. Stone ...

PURPOSE: To evaluate the detectability of urinary stones on virtual nonenhanced images generated at pyelographic-phase dual-energy computed tomography (CT). MATERIALS AND METHODS: This retrospective HIPAA-compliant study was institutional review board approved. All included patients had previously consented to the use of their medical records for research. Sixty-two patients (38 men, ...

To reconstruct the first and last sections of a helical computed tomographic (CT) scan, the scan length is automatically extended beyond the planned image boundaries, a phenomenon known as overranging. With common 16-section CT scanning protocols, the overrange length is between 3 and 6 cm. For scanners with 64 or ...

Acute ureteric colic is a common emergency, often dealt with by the emergency physician or general practitioner and referred on to the urologist. Unenhanced CT of the kidneys, ureters and bladder (CTKUB) is the 'gold standard' imaging investigation for establishing a diagnosis and guiding management. An appreciation of the CTKUB ...

OBJECTIVE: To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol. MATERIALS AND METHODS: Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to ...

The high convenience of data collection by helical scanning, such as making multi planner reformat (MPR) and shortening scan time, means that the technique is widely used to diagnose various body parts. However, non-helical scanning is still a main current for plane brain computed tomography. The possibility of diagnosing acute ...

The primary imaging modality for the detection of pulmonary metastases is computed tomography (CT). Ideally, a helical CT scan with 3- to 5-mm reconstruction thickness or a volumetric thin section scanning should be performed within 4 weeks of pulmonary metastasectomy. A period of observation to see whether further metastases develop ...

Unenhanced computed tomography (CT) is currently being widely used for the evaluation of patients presenting with acute flank pain. A variety of primary and secondary findings detected on unenhanced CT contribute not only to the diagnosis but also to the treatment plan. This review includes primary and secondary multidetector CT ...

The purpose of this study was to develop methods for the differentiation of urinary stones and vascular calcifications using computer-aided diagnosis (CAD) of non-contrast computed tomography (CT) images. From May 2003 to February 2004, 56 patients that underwent a pre-contrast CT examination and subsequently diagnosed as ureter stones were included ...

PURPOSE: To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making. METHODS: We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) ...

OBJECTIVE: To investigate the feasibility of using standard nonenhanced axial-mode scans as precontrast scans for bone elimination in cerebral CT angiography (CTA). MATERIALS AND METHODS: A consecutive dataset of 32 patients who had both cerebral nonenhanced CT (NECT) (scanned in axial mode) and subtraction CTA (scanned in helical mode) examinations ...

This study was conducted to assess the diagnostic yield of B-Mode Ultrasonography compared to unenhanced helical CT scan in detecting urinary stones in patients with acute renal colic. This retrospective study comprised of 156 patients who underwent unenhanced urinary tract CT scan and ultrasonography for suspicion of urolithiasis. Both techniques ...

PURPOSE: To determine the effect of reduced radiation (tube charge, measured as milliamperes per second) protocols on the sensitivity and specificity of multidetector computed tomography (CT) in the detection of renal calculi. MATERIALS AND METHODS: This Health Insurance Portability and Accountability Act-compliant human cadaveric study was approved by the Department ...

STUDY OBJECTIVE: We sought to determine the incidence of alternative diagnosis in patients with a history of kidney stones who experience recurrent symptoms and undergo repeat computed tomography (CT) imaging at their return to the emergency department (ED). METHODS: This was a retrospective chart review of ED patients at a ...

BACKGROUND: Recently a 320-detector-row CT (MDCT) scanner has become available that allows axial volumetric scanning of a 16-cm-long range (50 cm field of view) in a single 0.35-s rotation. For imaging neonates and small children, volume scanning is potentially of great advantage as the entire scan range can be acquired ...

INTRODUCTION: The characterization of urinary calculi using noninvasive methods has the potential to affect clinical management. CT remains the gold standard for diagnosis of urinary calculi, but has not reliably differentiated varying stone compositions. Dual-energy CT (DECT) has emerged as a technology to improve CT characterization of anatomic structures. This ...

We wanted to compare the image quality and radiation dose of retrospective versus prospective ECG-gated dual-source CT imaging in pediatric patients with congenital heart diseases. We retrospectively evaluated 44 thorax CT images that were obtained using two different protocols (retrospective helical ECG-gated [n = 22] versus prospective non-helical ECG-triggering [n ...

OBJECTIVE: To analyse the structure and composition of unattached stones in idiopathic calcium oxalate (CaOx) stone-formers (ICSF) and compare them to attached stones from the same cohort, to investigate whether there is more than one pathogenic mechanism for stone formation in ICSF. PATIENTS AND METHODS: ICSF undergoing percutaneous nephrolithotomy or ...

PURPOSE: To assess image quality and capability of stone differentiation between UA-containing and non-UA-containing uroliths with the latest dual-energy (DE) computed tomography (CT) system equipped with a tin filter (TF) using various data acquisition parameters in a work bench model. METHODS AND MATERIALS: One hundred ten urinary stones (4.2 +/- ...

Primary cutaneous mucinous carcinomas originating from sweat glands are rare tumors with patterns of spread that are difficult to predict. We present a case of a five times recurring eccrine mucinous adenocarcinoma of the scalp, previously treated with surgery and adjuvant radiation therapy. After magnetic resonance imaging (MRI) and 18F-fluoro-2-deoxyglucose ...

The objective of this article was developing an automated tool for routine clinical practice to estimate urinary stone composition from CT images based on the density of all constituent voxels. A total of 118 stones for which the composition had been determined by infrared spectroscopy were placed in a helical ...

BACKGROUND: To prospectively investigate the in vivo diagnostic performance of dual-energy (DE) computed tomography (CT) for the differentiation between uric acid (UA)-containing and non-UA-containing urinary stones. METHODS: DE CT scans were performed in 180 patients with suspected urinary stone disease using a dual-source CT scanner in the DE mode (tube ...

PURPOSE: To compare the detection of urinary stones using standard gray scale ultrasound for diagnostic accuracy using the color Doppler "twinkling sign". MATERIALS AND METHODS: Our study population consisted of forty-one patients who demonstrated at least one urinary stone on unenhanced CT evaluation of the kidneys or ureters. Each patient ...

OBJECTIVE: To assess the sensitivity of computed tomography (CT) scout topograms and kidney-ureter-bladder abdominal radiography (KUB) in detecting urinary tract stones. PATIENTS AND METHODS: We assessed films taken on presentation for 163 consecutive patients referred to our service for stone follow-up. Only those with both CT and KUB imaging on ...

A whole-body examination was performed with multidetector computed tomography (CT) of a completely wrapped Egyptian mummy from the collection at the Egyptian Museum in Turin, Italy. The mummy dates from the Eighteenth Dynasty. Although embalmment of the deceased man should have included evisceration in accordance with his social rank, no ...

Myelography and/or computed tomography (CT) are commonly used to evaluate acute intervertebral disk extrusion in chondrodystrophic dogs. The purpose of this study was to evaluate the sensitivity of myelography and two different CT protocols in determining level and lateralization of acute thoracolumbar intervertebral disk extrusion in comparison with surgical findings, ...

Startup of a 0.1 MA tokamak plasma is demonstrated on the ultralow aspect ratio Pegasus Toroidal Experiment using three localized, high-current density sources mounted near the outboard midplane. The injected open field current relaxes via helicity-conserving magnetic turbulence into a tokamaklike magnetic topology where the maximum sustained plasma current is ...

OBJECTIVE: The objective of our study was to compare the detection rate, conspicuity, and size measurements of urinary tract calculi on coronal reformations versus the axial plane using 64-MDCT. MATERIALS AND METHODS: For this retrospective study, 80 consecutive CT examinations performed for clinical diagnosis of renal colic or for the ...

For measuring the in-vivo range of motion of the hindfoot, a CT-based bone contour registration method (CT-BCM) was developed to determine the three-dimensional position and orientation of bones. To validate this technique, we hypothesized that the range of motion in the hindfoot is equally, accurately measured by roentgen stereophotogrammetric analysis ...

Drilling is one of the most complex techniques for making ancient stone implement or adornment. For smaller perforations, it is very difficult to effectively observe drilling marks under microscope, SEM, or to obtain negative silicone rubber cast. In this report, a new exclusive nondestructive method was first introduced to resolve ...

PURPOSE: To retrospectively determine the effect of 50% and 75% dose reduction on sensitivity and specificity of computed tomography (CT) for the detection of urinary calculi. MATERIALS AND METHODS: This HIPAA compliant study was institutional review board approved; informed consent was waived. Raw CT data from 47 consecutive patients (24 ...

Presented is a case of ureteral pseudodiverticulosis diagnosed by multidetector computed tomography (CT). Axial and coronal reformatted CT images revealed multiple small (2-4 mm) outpouchings of both ureters, characteristic of ureteral pseudodiverticulosis. The unenhanced CT also revealed a 6-mm stone at the left ureterovesical junction and a high attenuation lesion ...

BACKGROUND AND PURPOSE: Most series on ureteroscopy for urolithiasis use postoperative plain radiography of the kidneys, ureters, and bladder (KUB) or intravenous urography (IVU) to determine outcomes. These imaging modalities, however, are not very sensitive and may overestimate stone-free rates (SFRs). The aim of our study was to assess SFRs ...

Multisource cone-beam computed tomography (CT) is an attractive approach of choice for superior temporal resolution, which is critically important for cardiac imaging and contrast enhanced studies. In this paper, we present a filtered-backprojection (FBP) algorithm for triple-source helical cone-beam CT. The algorithm is both exact and efficient. It utilizes data ...

RATIONALE AND OBJECTIVES: The impact of varying image acquisition parameters on the precision of measurements using quantitative computed tomography is currently based on studies performed before the advent of helical image acquisition and multidetector-row scanners. The aim of this study was to evaluate helical multidetector-row quantitative computed tomography to determine ...

AIMS: To determine whether visibility of ureteral calculi on plain radiographs of the kidney, ureter and bladder (KUB) could be predicted based on characteristics on unenhanced helical computed tomography (UHCT) and CT scout radiographs (CTSR). METHODS: One hundred and twenty-three patients diagnosed with 140 ureteral calculi on UHCT, had undergone ...

Imaging has an essential role in the diagnosis, management, and follow-up of patients with stone disease. A variety of imaging modalities are available to the practicing urologist, including conventional radiography (KUB), intravenous urography (IVU), ultrasound (US), magnetic resonance urography, and computed tomography (CT) scans, each with its advantages and limitations. ...

OBJECTIVE: The purpose of our study was to prospectively determine optimal scan delays for multiphasic imaging of the kidney performed with multidetector row computed tomography (CT) and fixed injection duration of intravenous contrast medium. MATERIALS AND METHODS: One hundred ninety-eight patients underwent 3-phase CT of the kidney with 8-slice CT ...

OBJECTIVE: Survival in patients after surgical resection of pulmonary metastases correlates with the complete resection of all metastatic deposits. The purpose of this study was to evaluate the additional value of helical CT to see whether the slice thickness and the reading environment was a factor determining the accuracy of ...

AIM: To evaluate the association between computed tomography (CT) detection of early gastric cancer (EGC) and various parameters, including the depth of invasion, lesion extent, morpholgical type, location, and histological type. MATERIALS AND METHODS: One hundred and ten patients with 114 EGCs were preoperatively examined using multidetector CT (MDCT). All ...

OBJECTIVE: To develop a whole-kidney computed tomography (CT) technique that would allow 3-point Patlak plot determination of glomular filtration rate (GFR) and assess the correlation of GFR determined via CT (CT-GFR) with GFR determined via renal plasma clearance of inulin (Inu-GFR) in pigs. ANIMALS: 6 healthy anesthetized pigs. PROCEDURES: Each ...

OBJECTIVE: Renal calculi are sometimes incidentally detected on contrast-enhanced computed tomography (CT) scans. The purpose of this study was to evaluate the detectability of renal calculi on arterial phase CT. METHODS: One hundred thirty-three kidneys of 67 consecutive patients (one had prior unilateral nephrectomy) who underwent multidetector CT including noncontrast ...

BACKGROUND: Although urinalysis is simple and inexpensive to perform, the finding of microhaematuria on urinalysis may be unreliable for diagnosing urolithiasis. OBJECTIVE: To evaluate microhaematuria as a diagnostic marker for urolithiasis compared with low-dose unenhanced multidetector computed tomography (MDCT) as the "gold standard". SETTING: A level 1 emergency department in ...

OBJECTIVES: To determine the accuracy of stone size determination by computed tomography (CT) for distal ureteral calculi. METHODS: A total of 76 patients who presented with distal ureteral stone were evaluated with CT. Of the 76 patients, 41 successfully passed the stone spontaneously and intact. The largest stone size dimension ...

BACKGROUND AND AIM: Many technical developments of computed tomography (CT) made in recent years have improved imaging quality. However, the diagnostic efficacy of CT with coronal reconstruction for choledocholithiasis remains uncertain. This study aimed to investigate if CT with coronal reconstruction can aid in the diagnosis of choledocholithiasis. METHODS: Two ...