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 ...

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 ...

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. DE CT scans were performed in 180 patients with suspected urinary stone disease using a dual-source CT scanner in the DE mode (tube voltages 80 ...

To compare the detection of urinary stones using standard gray scale ultrasound for diagnostic accuracy using the color Doppler "twinkling sign". 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 was evaluated using gray ...

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 ...

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 ...

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 ...

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, ...

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 ...

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. ICSF undergoing percutaneous nephrolithotomy or ureteroscopy for the treatment ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

In this study, we proposed a new method of measuring temporal resolution using an impulse signal in the time domain in computed tomography (CT). We employed a metal ball with a diameter of 11 mm as the source of the impulse signal, which was shot to a slice plane at ...

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 ...

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 ...

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 ...

PURPOSE: We evaluated the effect of increased body habitus on stone-free rates after shockwave lithotripsy (SWL), determined by three reproducible skin-to-stone distances (SSDs) on CT. PATIENTS AND METHODS: We retrospectively reviewed the records of 85 patients with preoperative CT scans available on Stentor Radiology Imaging who underwent SWL with the ...

Diagnostic computed tomography (CT) images are usually acquired in both helical and axial scans in the clinical applications using cone beam volumetric CT. In addition to faster patient throughput, a helical scan in volumetric CT can provide better image quality because of the satisfaction of data sufficiency condition, and thus ...

OBJECTIVE: We describe CT features of our three cases with localized Castleman disease in the retroperitoneum and review literature. Besides those CT features, which have been reported before, we mainly present some newly discovered CT findings of the disease. These new CT findings include the sign of peripheral 'rim-like' enhancement ...

This article describes the principles and evolution of multislice CT (MSCT), including conceptual differences associated with slice definition, cone beam effects, helical pitch, and helical scan technique. MSCT radiation dosimetry is described, and dose issues associated with MSCT-and with CT in general-as well as techniques for reducing patient radiation dose ...

OBJECTIVE: The objective of our study was to evaluate the feasibility of virtual unenhanced images reconstructed from a dual-energy CT scan to depict urinary stones in an iodine solution in a phantom study. MATERIALS AND METHODS: Twenty urinary stones of different sizes (1.4-4.2 mm in short-axis diameter) were placed in ...

Posterior fossa artifacts constitute a characteristic limitation of cranial CT. To identify practical benefits and drawbacks of newer CT systems with reduced collimation in routine cranial imaging, we aimed to investigate image quality, posterior fossa artifacts and parenchymal delineation in non-enhanced CT (NECT) with 1-, 4-, 16- and 64-slice scanners ...

Radiology has a primary role in the work-up of renal colic, both to confirm urolithiasis and to help determine management. The traditional imaging has been conventional radiography and intravenous program with multidetector non-contrast-enhanced helical computed tomography (NCECT) now the modality of choice. Nuclear medicine studies for renal colic are done ...

AIM: Compare the performances of EUS to helical CT in the diagnosis and staging of pancreatic adenocarcinoma. METHODS: Forty two consecutive patients (mean age 63 years; 25 men, 17 women) who had surgical exploration and histologically proved pancreatic cancer were retrospectively included. All our patients underwent with endoscopic ultrasonography (EUS) ...

The gantry-tilted helical cone-beam computed tomography (CT) has an inherent problem that the relative shift of the region of interest (ROI) blurs the reconstructed image. This problem becomes more serious in the gantry-tilted local CT imaging due to the nature of local scanning. This paper proposes a new method to ...

PURPOSE: There is increasing concern about the risks of radiation exposure with the advent of new, more complex imaging modalities. For example, computed tomography (CT), with its obvious advantages, is being more commonly used in the investigation of acute flank pain. The likely radiation exposure a patient can expect during ...

PURPOSE: Magnetic resonance cholangiopancreatography (MRCP) is not sufficient to detect pancreaticobiliary maljunction (PBM) in young infants because the main pancreatic duct is not visualized and respiratory artifacts occur. To our knowledge, there are no reports highlighting the diagnostic accuracy of evaluation using the axial planes of helical computed tomographic (CT) ...

OBJECTIVE: The purpose of this study is to assess the accuracy of dual energy CT (DECT) in the characterization of renal and ureteral stones. MATERIAL AND METHODS: Twenty-four renal calculi of known variable composition were scanned on a dual-source CT scanner (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) in dual ...

OBJECTIVES: To evaluate intraoperative decision making regarding the necessity of second-look nephroscopy after percutaneous nephrolithotomy. METHODS: Percutaneous nephrolithotomy was performed cooperatively by a urologist and radiologist equipped with a high-resolution C-arm. Ultrasonic lithotripsy was performed followed by thorough flexible nephroscopy and fluoroscopy. At conclusion patients were prospectively classified as radiologically ...

BACKGROUND: We wondered whether noncontrast CT performs better than the intravenous urogram (IVU) in the detection of urinary calculi. METHODS: A comprehensive search of the literature was undertaken in order to answer the above question. Both primary and secondary sources of evidence were searched. The retrieved evidence was then appraised. ...

Nowadays, computed tomography (CT) is established for diagnosing gastrointestinal bleeding. In this retrospective study, the use of CT in diagnosing gastrointestinal bleeding was evaluated. Fifty-three patients received a contrast-medium-enhanced helical multislice CT (MSCT) to locate the bleeding site. Seventy-nine percent of the hemorrhage were acute gastrointestinal bleedings. Fifty-five percent of ...

BACKGROUND: The purpose of this prospective study was to evaluate the feasibility of replacing intravenous urography (IVU) with unenhanced computed tomography (CT) as the first line diagnostic modality for acute renal colic in the emergency department. METHODS: In the 1-year study period, 82 patients who presented themselves to the emergency ...

PURPOSE: To compare multidetector CT scan (MDCT) results with intraoperative findings in the detection of an inferior-pole pedicle crossing the ureteropelvic junction. PATIENTS AND METHODS: Over the 2-year study period, 35 patients receiving laparoscopic pyeloplasty underwent preoperative investigation with a novel MDCT protocol in order to detect crossing vessels. Postprocessing, ...

OBJECTIVES: To assess the value of dual-energy contrast-enhanced computed tomography (CT) imaging for the detection of urinary stone disease using dual-source CT. MATERIALS AND METHODS: Forty consecutive patients (mean age 46.6 +/- 16.2 years, range 27-85 years) suspected of having urinary stone disease underwent dual-source CT of the urinary tract. ...

PURPOSE: To compare angiographic computed tomographic (CT) imaging with standard spiral CT imaging for the depiction of extraosseous cement after vertebral augmentation. MATERIALS AND METHODS: Retrospective analysis of 28 consecutive patients treated with vertebral augmentation for compression fracture was conducted. Intraprocedural angiographic CT and postprocedural spiral CT images were acquired ...