OBJECTIVE: The purpose of this study was to determine if the radiographic visibility of urinary tract calculi could be predicted on the basis of CT features. MATERIALS AND METHODS: The images of 26 patients whose urinary tract calculi were revealed on unenhanced helical CT and who also underwent digital abdominal ...

Spiral computed tomography (CT) is the state of the art today in imaging many features of the genitourinary tract. The use of dual-phase CT imaging improves our ability to detect and stage a wide range of pathologies. However, imaging in the arterial phase has several potential pitfalls that can result ...

The diagnosis and initial management of urolithiasis have undergone considerable evolution in recent years. The application of noncontrast helical computed tomography (CT) in patients with suspected renal colic is one major advance. The superior sensitivity and specificity of helical CT allow urolithiasis to be diagnosed or excluded definitively and expeditiously ...

Using a fresh frozen cadaver head, a series of axial helical CT scans were obtained using varying imaging parameters both before and after traumatizing the head. The appearance of reformatted coronal images was optimized for the lowest radiation dose. A protocol for imaging the maxillofacial region was developed that produced ...

BACKGROUND: Proper recognition, classification and assessment of the tracheobronchial anatomy are essential for surgical management planning in left pulmonary artery sling (LPAS). OBJECTIVE: To demonstrate the various imaging modalities in diagnosing and assessing anatomical relationships with tracheobronchial tree in LPAS. MATERIALS AND METHODS: Seven patients (three infants, three children, one ...

OBJECTIVE: This study seeks to evaluate three-dimensional (3D) helical CT portography as a tool for examining patients with gastric fundic varices. SUBJECTS AND METHODS: We compared 3D helical CT portography and conventional angiographic portography in 30 consecutive patients with gastric fundic varices. We assessed whether 3D helical CT portography is ...

Multislice compound tomography (MCT) is one of the recent technology advancements in CT. Compared to single slice CT, MCT significantly improves examination time, x-ray tube efficiency, and contrast material utilization. Although the scan mode of MCT is predominately helical, step-and-shoot (axial) scans continue to be an important part of routine ...

OBJECTIVE: The purpose of this study was to ascertain whether the difference in attenuation frequently noted on unenhanced helical CT scans between a patient's acutely obstructed kidney and the unobstructed kidney is a reliable secondary sign of acute renal obstruction. CONCLUSION: In 95% of patients with acute renal obstruction, the ...

OBJECTIVE: The diagnostic value of unenhanced helical computed tomography (CT) for the evaluation of acute flank pain is investigated in a prospective study. PATIENTS AND METHODS: In 125 patients aged 18-86 years, we performed unenhanced helical CT in addition to abdominal plain film, abdominal ultrasound and urinalysis as a diagnostic ...

We prospectively evaluated subtalar inversion stress views (Brodén view) with inversion stress views on helical CT in a group of 10 patients with unilateral instability. The contralateral, asymptomatic ankle was used as control. All patients were examined with inversion stress views on plain stress radiography and helical CT. Subtalar tilt ...

PURPOSE: To determine whether the perirenal spaces communicate across the midline and with the pelvic extraperitoneal spaces. MATERIALS AND METHODS: Helical CT was used to guide the sequential injection of 100-mL intravenous boluses of dilute contrast medium, up to 300 mL, into the perirenal space of eight embalmed cadavers (three ...

To compare how often the central lucency of pelvic phleboliths is seen on plain radiographs and noncontrast helical computed tomography (CT), both images in 70 patients with renal colic were analyzed. Both images revealed the same number of phleboliths in all cases except one in which one of two phleboliths ...

PURPOSE: The purpose of this work was to determine the reproducibility of coronary total calcium score (TCS) with dual-slice helical CT and compare three acquisition protocols. METHOD: Fifty patients (59 +/- 10 years old) underwent dual-slice helical CT (collimation = 2 x 2.5 mm) and coronary angiography. Two successive scans ...

OBJECTIVE: This study evaluated helical CT as an imaging modality for preoperative staging of endometrial carcinoma. MATERIALS AND METHODS: Three radiologists retrospectively and independently reviewed the preoperative helical CT scans of 25 consecutive patients with endometrial carcinoma. The presence or absence of deep myometrial invasion and the presence or absence ...

PURPOSE: We validated the descriptive characteristics of emergency cases presenting with urolithiasis, determined the incidence of normal urinalysis in such cases and compared the expense of diagnostic computerized tomography (CT) and excretory urography (IVP). MATERIALS AND METHODS: We retrospectively reviewed the charts of all consecutive patient visits to a community ...

Informed selection of treatment requires knowledge of the size and composition of a calculus. Spiral CT has a growing role in the detection of calculi, with an overall accuracy in excess of 95%. Moreover, the margin of error in determining stone size does not exceed 3.6%, and stone volume is ...

BACKGROUND: The relative accuracy of helical CT and EUS for defining the local resectability of peripapillary malignancies is undefined. METHODS: Fifty-one patients with a peripapillary malignancy and no metastatic disease were prospectively evaluated with helical CT and EUS. Imaging results were compared with surgical staging, and a tumor was defined ...

Unenhanced helical CT allows rapid and accurate determination of whether a stone is present anywhere in the urinary tract. There is a learning curve for both radiologist and urologist, but a number of signs are highly predictive of stone. Helical CT scans should always be accompanied by a "scoutogram" to ...

In the past decade alternatives to urography have been proposed for the study of patients with renal colic. In 1992 it was suggested to replace urography with KUB and ultrasonography. In 1993 the combination of KUB and ultrasonography followed by urography in unresolved cases was proposed and, in 1995, it ...

The goal of this study was to determine the diagnostic value of the helical CT without contrast in suspected cases of choledocholithiasis, comparing this test with endoscopic retrograde cholangiopancreatography (ERCP). Forty patients with possible choledocholithiasis were studied prospectively. There were 23 women and 17 men, ranging in age from 24 ...

In tracheo- and bronchomalacia, localisation and determination of collapse is necessary for planning of surgical procedure. We compared inspiratory and expiratory spiral CT, cine CT, bronchoscopy, exemplary cine MR, and evaluated the clinical relevance. Twenty-nine patients (2 follow-ups; mean age 61 years, age range 27-85 years) with suspected or verified ...

Tumors arising within a horseshoe kidney are uncommon and may be difficult to characterize. We report a case of transitional cell carcinoma in a horseshoe kidney. Although several conventional imaging techniques were used to define the mass, each provided limited information. Recent advances in computer technology permit radiologic imaging to ...

PURPOSE: To prospectively evaluate helical computed tomography (CT) in the preoperative detection of hepatic metastases and assessment of resectability with surgical, intraoperative ultrasonographic (US), and histopathologic correlation. MATERIALS AND METHODS: Between October 1995 and December 1998, preoperative staging with helical CT (5-mm collimation; reconstruction interval, 5 mm) was performed in ...

We report a case of agnathia-holoprosencephaly which was prenatally diagnosed based on helical computed tomography (CT) images obtained at 23 weeks of gestation. Ultrasound examination first showed the presence of alobar holoprosencephaly, but the facial structures were not clearly detailed. However, three-dimensional imaging by helical CT precisely demonstrated the most ...

PURPOSE: To compare nonenhanced helical computed tomography (CT) with ultrasonography (US) for the depiction of urolithiasis. MATERIALS AND METHODS: During 9 months, 45 patients (mean age, 44 years; mean weight, 92.5 kg) prospectively underwent both nonenhanced helical CT (5-mm collimation; pitch of 1.5) and US of the kidneys, ureters, and ...

The purpose of this study was to evaluate the efficacy of three-dimensional (3-D) images produced with a helical CT for the diagnosis of lesions occurring in the maxillofacial region. Thirty-four patients, who had lesions in the maxillofacial region, were examined by plain radiography (intra and extraoral) and the helical CT. ...

BACKGROUND: The new transxiphoid video-assisted approach allows manual palpation of both lungs, thus permitting better evaluation of helical computed tomography (CT) in detection of pulmonary metastases. METHODS: From December 1995 to May 1999, 22 patients underwent a transxiphoid video-assisted pulmonary metastasectomy. Manual palpation of both lungs was possible in 18 ...

OBJECTIVE: Our purpose was to evaluate thick-section reformatted helical CT of the brain base as a technique for reducing skull base-related artifacts and to compare it with conventional CT. MATERIALS AND METHODS: Twenty-three patients with suspected intracranial abnormalities related to the brain base, as determined either by clinical examination or ...

Multisection computed tomography (CT) was introduced in 1992 with the advent of dual-section-capable scanners and was improved in 1998 following the development of quad-section technology. With a recent increase in gantry speed from one to two revolutions per second, multisection CT scanners are now up to eight times faster than ...

To evaluate the usefulness of stereoscopic images of larynges using helical CT in stereo mode, a retrospective review of the characteristics of stereoscopic viewing of larynges was made. The subjects were 3 patients with laryngeal cancer, 1 patient with laryngeal leiomyosarcoma and 1 patient with an advanced tongue carcinoma whose ...

PURPOSE: To evaluate the accuracy of dual-section helical computed tomography (CT) in acute pulmonary embolism (PE) diagnosis. MATERIALS AND METHODS: Of 204 consecutive patients with clinically suspected acute PE (mean age, 58 years +/- 14 [SD]), 158 were enrolled. All patients underwent dual-section helical CT (2.7-mm effective section thickness) and ...

The intravenous urogram (IVU) remains a useful investigation in the assessment of upper urinary tract calculi. Helical computed tomography scanning appears to have superseded the IVU in the diagnosis of acute flank pain due to a higher sensitivity in diagnosis. Results of extracorporeal shockwave lithotripsy (ESWL) for lower calyceal stones ...

BACKGROUND: Multisection helical computed tomography (CT) has the potential for providing data sets with better section profiles, more anatomic coverage, and shorter breath-holding periods. Our purpose was to quantitate these advantages in a clinical setting when imaging the abdomen and pelvis. METHODS: CT parameters including collimation, timing, z-axis coverage, and ...

BACKGROUND/AIMS: ERCP is an established method for the diagnosis and treatment of common bile duct stones, however, it is invasive, time-consuming, and expensive. The purpose of this study was to determine whether unenhanced spiral CT and US, compared with ERCP, have sufficient sensitivity and negative predictive value to be useful ...

We set out to evaluate the accuracy of nonenhanced helical computed tomography (CT) scanning at stone detection in the patient with acute flank pain, and as a means of detecting noncalculus causes of acute flank pain. Between April 1995 and April 1997, 412 consecutive patients with acute flank pain underwent ...

BACKGROUND: The standard evaluation of mediastinal gunshot wounds usually requires angiography and either esophagoscopy or esophagography. In the present study, we have evaluated the role of helical computed tomographic (CT) scanning in reducing the need for angiographic and esophageal studies. METHODS: This was a prospective study of patients with mediastinal ...

OBJECTIVE: This study was undertaken to determine the sensitivity and specificity of coronal images reformatted from helical thin-section axial CT data obtained for the evaluation of maxillofacial fractures. MATERIALS AND METHODS: Multiple fractures were created in nine cadaver heads by blunt trauma and were then evaluated using a late-generation helical ...

BACKGROUND: The purpose of this study was to evaluate the use of dynamic helical computed tomography (CT) scan for screening patients with pelvic fractures and hemorrhage requiring angiographic embolization for control of bleeding. METHODS: Patients admitted to the trauma service with pelvic fractures were identified from the trauma registry. Data ...

OBJECTIVE: In this investigation we compared the diagnostic performance of unenhanced helical CT, oral contrast-enhanced CT cholangiography, and MR cholangiography for the diagnosis of choledocholithiasis. SUBJECTS AND METHODS: Fifty-one patients referred for endoscopic retrograde cholangiography of suspected biliary stones were studied with unenhanced helical CT, MR cholangiography, and helical CT ...

Helical computed tomography (CT) was used to demonstrate the distribution of crossing vessels in patients with ureteropelvic junction (UPJ) obstruction for planning surgical management. Twenty patients with symptomatic UPJ obstruction were evaluated with dual-phase contrast material-enhanced helical CT. In addition to axial images, coronal, sagittal, and curved paracoronal images along ...

RATIONALE AND OBJECTIVES: The aim of our study was to assess the image quality, radiation dose, and clinical applicability of low-dose, volumetric helical CT in the evaluation of bronchiectasis. METHODS: Volumetric helical CT scans (120 kVp, 3-mm collimation, pitch of 2, and reconstruction interval of 2 mm) were obtained through ...

PURPOSE: To determine the accuracy and utility of unenhanced helical CT for suspected renal colic, using a pitch of either 2.5 or 3.0. METHODS: 59 consecutive patients underwent unenhanced helical CT. 5 mm contiguous images were obtained at a kVP of 120 and an mA of 260. Thirty-four patients were ...

BACKGROUND AND PURPOSE: Helical CT has become the preferred method for imaging urinary calculi, and so it would be useful if data from helical CT could also be used to predict the number of shockwaves (SWs) needed to break a given stone. METHODS AND MATERIALS: We measured the number of ...

PURPOSE: Urolithiasis followup with plain abdominal x-ray requires adequate visualization of the calculus on the initial x-ray or computerized tomography (CT) study. We compared the sensitivity of plain abdominal x-ray versus CT for stone localization after positive nonenhanced spiral CT. MATERIALS AND METHODS: We evaluated 46 consecutive nonenhanced spiral CT ...

OBJECTIVE: Helical CT has become the preferred methodology for identifying urinary calculi. However, the ability to predict stone composition, which influences patient treatment, depends on the accurate measurement of the radiographic attenuation of stones. We studied the effects of stone composition, stone size, and scan collimation width on the measurement ...

The purpose of this study was to compare the performance of magnetic resonance (MR) imaging using currently available techniques with contrast-enhanced single-phase helical computed tomography (CT) in depicting extrahepatic disease in patients with malignancy. At two institutions, 164 patients with known or suspected malignancy underwent abdominal imaging with contrast-enhanced helical ...

OBJECTIVE: We compared the sensitivity of CT scout radiography with that of abdominal radiography in revealing ureteral calculi on unenhanced helical CT. MATERIALS AND METHODS: Over a 6-month period, patients presenting to the emergency department with acute flank pain were examined with standard abdominal radiography and unenhanced helical CT, which ...

PURPOSE: To compare the effects of acquisition parameters on the magnitude and appearance of artifacts between single and multiple detector-row helical computed tomography (CT). MATERIALS AND METHODS: A cylindric (12.7 x 305.0-mm) acrylic rod inclined 45 degrees relative to the z axis was scanned at the isocenter and 100 mm ...

OBJECTIVES: To determine the incidence and spectrum of significant alternative or additional diagnoses established or suggested on unenhanced helical computed tomography (CT) in a large series of patients with suspected renal colic. METHODS: One thousand consecutive unenhanced helical CT examinations were performed for suspected renal colic. All official CT reports ...

With the advent of helical CT, the capability of noninvasive imaging of the thoracic aorta has been enhanced considerably. In this article, we describe the potential of helical CT using dual-slice technology to evaluate thoracic aortic diseases such dissection, aneurysm, trauma, infection, inflammation, thromboembolic disease, and postoperative complications. Technical considerations ...