SUMMARY: Oxygen-enhanced magnetic resonance (MR) ventilation imaging is a new technique, and the full extent of its physiologic significance has not been elucidated. This review article includes (1) theory of oxygen enhancement; (2) respiratory physiology; (3) oxygen-enhanced MR imaging (MRI) sequence design; (4) basic study of oxygen-enhanced MRI in animal ...

PURPOSE: To compare dynamic gadolinium-enhanced T1-weighted magnetic resonance (MR) imaging with nonenhanced T1-weighted and T2-weighted MR imaging and thin-section computed tomography (CT) for the demonstration of osteoid osteomas. MATERIALS AND METHODS: The images of 11 patients with pathologically proven osteoid osteomas who underwent nonenhanced MR imaging, dynamic gadolinium-enhanced MR imaging, ...

PURPOSE: To evaluate whether computed tomographic (CT) colonography with intravenously administered contrast material can help predict malignant differentiation of colorectal neoplasms (> or =10 mm in diameter). MATERIALS AND METHODS: Enhancement of 29 consecutive colorectal neoplasms on pre- and postcontrast CT colonographic images was retrospectively measured. The neoplasms were subsequently ...

Various complex pharmacokinetic interrelationships affect the use of contrast media for computed tomography (CT) imaging. These include factors related to each patient's unique body habitus and their degree of health, such as their age, gender, height, weight, and cardiovascular status. Of equal importance are factors related to the contrast material ...

OBJECTIVE: The aim of this study was to compare the sensitivity of pulse inversion harmonic digital sonography, unenhanced transabdominal sonography, and ferumoxides-enhanced MR imaging in the depiction of liver metastases. In addition, pulse inversion harmonic digital sonography was performed at different scanning times after Levovist injection to define the best ...

OBJECTIVE: To report our experience in the assessment of splenic trauma with contrast-coded sonography and a second-generation contrast medium. METHODS: From January to May 2002, 120 patients were studied with sonography for suspected splenic trauma. Twenty-five were selected for further imaging because of sonographic findings positive for splenic injury, findings ...

OBJECTIVE: To evaluate patients with clinically active rheumatoid arthritis (RA) of the shoulder for joint effusion and synovitis using conventional sonography, power Doppler (PD) sonography with and without echo-enhancing contrast agent, and contrast-enhanced MRI. DESIGN AND PATIENTS: Twenty-four patients (mean age 64 years) with known RA had one symptomatic shoulder ...

PURPOSE: To investigate pharmacokinetic and physiologic factors that determine the time to peak intravenous contrast medium enhancement in computed tomographic (CT) and magnetic resonance (MR) angiography in the porcine mid-abdominal aorta. MATERIALS AND METHODS: Four pigs were imaged repeatedly in seven to eight sets: For each set, 20 dynamic CT ...

BACKGROUND AND PURPOSE: To develop an MR imaging method that improves detection of leptomeningeal disease when compared with the current reference standard, contrast-enhanced T1-weighted imaging. METHODS: We investigated the cases of 10 children who were at high risk of intracranial leptomeningeal disease (Sturge-Weber syndrome and medulloblastoma). The cases of Sturge-Weber ...

OBJECTIVE: Contrast-enhanced MR imaging has great clinical value as a means of characterizing myocardial tissue in patients with ischemic heart disease. The purpose of our study was to evaluate use of this technique in the assessment of patients with hypertrophic cardiomyopathy. CONCLUSION: On late-enhancement MR imaging, the various types or ...

PURPOSE: To compare conventional B-mode ultrasonography (US) alone with the combination of conventional B-mode US and contrast material-enhanced (SHU 508A) late-phase pulse-inversion US for the detection of hepatic metastases by using dual-phase spiral computed tomography (CT) as the standard of reference. MATERIALS AND METHODS: One hundred twenty-three patients underwent conventional ...

Optimal contrast medium delivery remains a crucial issue in CT angiography and it will become even more critical with continuously evolving, faster CT scanner technology. This review article first explains the fundamentals of arterial enhancement using mathematical models of early contrast medium dynamics. The relationship of contrast medium volume, injection ...

PURPOSE: To present a case of tonic pupil associated with enhancement in the region of the ciliary ganglion on magnetic resonance imaging in a patient with sarcoidosis. DESIGN: Observational case report. METHODS: A 52-year-old woman with sarcoidosis had a right pupil exhibiting sectoral palsy to light and light-near dissociation. RESULTS: ...

Numerous complex pharmacokinetic interrelationships affect the use of contrast media for computed tomography (CT) imaging. The volume, concentration, and rate of injection, all affect the degree of enhancement that is achieved with an injection of contrast material. In addition, the injection technique, whether the contrast is infused with a constant ...

PURPOSE: To evaluate the value of serially obtained spinal MR images in the diagnosis and clinical follow-up of childhood Guillain-Barré syndrome (GBS), and the time period for resolution of contrast enhancement during the course of illness. MATERIAL AND METHODS: Contrast-enhanced spinal MR images of 11 pediatric patients with GBS were ...

OBJECTIVES/HYPOTHESIS: Magnetic resonance imaging (MRI) has become the investigation of choice to follow up patients after vestibular schwannoma resection. STUDY DESIGN: Retrospective. METHODS: Postoperative MRI findings of 70 patients after vestibular schwannoma resection through a transtemporal (n = 48) and a translabyrinthine (n = 22) approach were reviewed. Time-dependent changes ...

Magnetic resonance imaging (MRI) reveals cardiac signal intensity changes in patients with acute myocarditis; however, the natural history of these changes and their relationship to individual outcomes are unknown. The relationship of MRI findings to long-term outcome was studied by serial MRI studies in 16 patients with acute myocarditis who ...

BACKGROUND: The aim of this study is to assess the usefulness of three-dimensional contrast-enhanced magnetic resonance (MR) imaging, compared with galactography and ultrasonography(US). METHODS: Fifty-five patients with bloody nipple discharge were investigated retrospectively. All patients were examined by galactography, ultrasonography and MR imaging. These three sets of findings were compared ...

The aim of this study was to simplify the imaging of myocardial infarction based on theoretical aspects and patient variables and to define the optimal time for image acquisition. Thirteen patients with chronic myocardial infarction underwent magnetic resonance imaging. After injection of 0.2 mmol/kg body weight Gd-DTPA an inversion recovery ...

We report a case of cerebral fat embolism (CFE) that was imaged with T2- and T2*-weighted, fluid-attenuated inversion recovery, and contrast-enhanced T1-weighted images. Multiple white matter lesions demonstrated contrast enhancement, with little evidence of hemorrhage. The patient regained complete neurologic function. CFE can cause capillary inflammation and breakdown of the ...

Invasive lobular carcinoma (ILC) may be a difficult tumor to detect early by physical examination, mammography, or ultrasound. We undertook this study to describe the spectrum of gadolinium enhancement and morphologic features of ILC on magnetic resonance imaging (MRI). Nineteen patients with ILC who presented with a palpable mass, a ...

The utility of three-dimensional spoiled gradient recalled acquisition in steady state (3D-SPGR) imaging in the cerebral diseases was evaluated and 3D-SPGR after enhancement in depicting contrast enhancement of all lesions and 2D-SE T1WI comparatively analyzed. 117 patients were subjected to MRI by a GE 1.5T MR system. After performance of ...

OBJECTIVE: The objective of our study was to describe the functional and differential uptake features of atypical focal nodular hyperplasia using different MR contrast agents and to evaluate their potential role in the diagnosis and characterization of focal nodular hyperplasia. MATERIALS AND METHODS: Contrast-enhanced MR images of 45 patients with ...

STUDY OBJECTIVES: To explore the diagnostic performance of MRI for the diagnosis of acute myocarditis, using a comprehensive imaging approach. DESIGN AND SETTINGS: Twenty patients with myocarditis and 7 age-matched and gender-matched control subjects underwent comprehensive MRI. Magnetic resonance (MR) examinations included axial T2-weighted sequences, precontrast and postcontrast ECG-gated T1-weighted ...

The authors describe a unique presentation of Wegener granulomatosis (WG) manifesting predominantly as meningitis. Magnetic resonance imaging demonstrated diffuse meningeal enhancement, including the pia mater, in a 28-year-old man with meningitis. A diagnosis of atypical WG was based on the findings of a dural biopsy sample and an elevated cytoplasmic ...

Conventional teleradiology is a useful tool, but sometimes we have found it to be an insufficient means of investigation because the radiological specialists cannot indicate the imaging protocol during the investigation. The purpose of our study was to evaluate the efficacy of real-time teleradiology, which will improve the quality of ...

RATIONALE AND OBJECTIVES: Myocardial fibrosis was evaluated with magnetic resonance (MR) imaging in Bio14.6 hamsters. MATERIALS AND METHODS: Gated gradient-echo T1-weighted images and spin-echo images with gadopentetate dimeglumine enhancement (0.2 mmol/kg) were obtained. RESULTS: Myocardial enhancement persisted for 13 minutes after administration of gadopentetate dimeglumine, and myocardial signal intensity peaked ...

BACKGROUND: Fluoroscopic micturating cystourethrography (MCU) is used for screening and grading of vesicoureteral reflux (VUR). It involves ionizing radiation. This study was designed to assess the efficacy of contrast-enhanced sonography in predicting the presence or absence of VUR. OBJECTIVE: To compare an ultrasound contrast agent for detection of VUR in ...

The purpose of our study is to report personal experience about 28 cases of Ductal Carcinoma In Situ (DCIS) studied with Magnetic Resonance Imaging (MRI). From September 1995 to December 2001, 28 women affected by DCIS lesions underwent contrast enhanced MRI. All patients were submitted previously to mammographic examination. The ...

PURPOSE: To establish a quantitative magnetic resonance (MR) imaging contrast enhancement criterion for distinguishing cysts from solid renal lesions. MATERIALS AND METHODS: Regions of interest were measured in 74 patients with renal lesions evaluated by means of dynamic contrast material-enhanced MR imaging with serial breath-hold spoiled gradient-echo acquisitions. Sensitivity for ...

OBJECTIVE: The purpose of our study was to compare the diagnostic accuracy and lesion conspicuity of ferumoxides-enhanced MR imaging with those of mangafodipir trisodium-enhanced MR imaging for the preoperative detection of hepatocellular carcinoma. SUBJECTS AND METHODS: Twenty-one patients with 39 hepatocellular carcinomas underwent ferumoxides-enhanced and mangafodipir trisodium-enhanced MR imaging. The ...

In this study, we reviewed the computed tomography (CT, n=9) and magnetic resonance (MR, n=5) imaging findings of 11 patients with pathologically confirmed cerebral hydatid disease. Among our patients, there were 10 cases of Echinococcus granulosus and 1 case of Echinococcus multilocularis. Common CT and MR imaging findings of E. ...

PURPOSE: To study the pattern of contrast enhancement in MR and CT of oligodendrogliomas and to compare this with other imaging findings and with histopathological grading criteria. MATERIAL AND METHODS: 20 patients with oligodendrogliomas (12 low-grade WHO II and 8 anaplastic WHO III) were reviewed. 20 complete MR investigations, 20 ...

BACKGROUND: Tuberculosis (TB) of the spine is the most common site of osseous involvement and has a higher prevalence in developing nations with an increasing incidence in developed nations. There are few paediatric reports of TB spondylitis (TBS) that include MRI findings. OBJECTIVE: To determine the MRI characteristics of TBS ...

RATIONALE AND OBJECTIVES: The authors performed this study to assess the effects of furosemide-induced diuresis on paramagnetic contrast material enhancement at magnetic resonance (MR) imaging of the kidney, liver, spleen, and psoas muscle. MATERIALS AND METHODS: Twenty-five patients (average age, 44.9 years; age range, 23-74 years; 13 men, 12 women) ...

The practicability of using Overhauser enhancement of saline in interventional MRI was investigated. Saline was used as a means of marking the path taken by a fluid-filled cavity, similar to that formed by a needle, catheter, or cannula during interventional MRI procedures. A prototype device was designed and constructed for ...

Our objective was to assess the value of delayed contrast-enhanced T1-weighted spin-echo MR imaging in the detection of residual cholesteatoma in patients who have undergone canal wall-up tympanoplasty procedure. The MR imaging was obtained prior to revision surgery in 18 patients with opacity of the post-operative cavity at CT examination ...

We report a pediatric patient with a posterior fossa ependymoma in whom the second of two magnetic resonance imaging (MRI) scans obtained preoperatively within a 10-day span showed intense but transient disseminated enhancement. However, following posterior fossa craniotomy for near total tumor resection, neither three MRI exams nor two craniospinal ...

OBJECTIVE: The aim of our study was to evaluate prospectively the grades and patterns of gadopentetate-enhanced MR imaging in the radiocarpal joints of healthy subjects after IV contrast administration. SUBJECTS AND METHODS: The study included 18 healthy subjects (nine men, nine women; age range, 24-34 years; mean age, 30.8 years). ...

RATIONALE AND OBJECTIVES: This study was conducted to compare the magnetic resonance (MR) contrast medium enhancement of abdominal organs in vivo with the signal intensity (SI) values of known in vitro gadolinium solutions. MATERIALS AND METHODS: A phantom was imaged with the MR contrast medium gadodiamide (Omniscan; Nycomed, Princeton, NJ) ...

PURPOSE: To evaluate magnetic resonance (MR) imaging findings of radiation-induced cranial arteritis regarding arterial wall thickening and degree of enhancement, as well as to compare the findings with those of idiopathic moyamoya disease. MATERIALS AND METHODS: We reviewed cerebral MR images in five patients with radiation-induced large cerebral arteritis. All ...

PURPOSE: To evaluate whether mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance (MR) imaging surpasses dual-phase spiral computed tomography (CT) in differentiating focal liver lesions. MATERIALS AND METHODS: One hundred forty-five patients who had or were suspected of having focal liver lesions were included in a multicenter study and underwent dual-phase spiral CT ...

OBJECTIVES: To evaluate computed tomography (CT) densitometry as a technique for quantifying contrast enhancement of compressive soft tissues in the canine lumbosacral vertebral canal and to determine whether the degree of contrast enhancement can be used to help predict tissue type or histopathologic characteristics. ANIMALS: 29 large breed dogs with ...

BACKGROUND AND PURPOSE: Recent work has shown that fluid-attenuated inversion recovery (FLAIR) imaging with contrast enhancement is highly sensitive for detecting subarachnoid space disease. We hypothesized that contrast-enhanced FLAIR imaging has superior sensitivity to contrast-enhanced T1-weighted MR imaging in detecting leptomeningeal metastases. METHODS: Sixty-eight patients referred for suspected leptomeningeal metastases ...

Magnetic resonance imaging (MRI) has been used to examine conditions that alter the permeability of the blood-retinal barrier. Our goal was to determine if blood-aqueous barrier permeability could be similarly assessed, because MRI offers the theoretical advantage of providing quantitative data directly from inflamed uveal tissues rather than from the ...

We report a case of multiple myeloma with gastric involvement occurring in a patient who underwent an upper gastrointestinal series (UGIS), CT and MRI. UGIS depicted a luminal protruding mass, while contrast-enhanced CT demonstrated marked thickening of the gastric wall, with subtle contrast enhancement. At T1- and T2-weighted MR imaging, ...

The aim of this study was to compare peripheral nodular enhancement with centripetal progression on contrast-enhanced coded harmonic angio (CHA) with those as seen on magnetic resonance imaging (MRI) scan. A total of 20 patients with 24 hemangiomas confirmed by dynamic contrast-enhanced MRI were included in this study. All 20 ...

Radiographic contrast agents using gadolinium have a better safety profile and photoelectric effect than iodinated contrast, allowing use where iodinated contrast is contraindicated. A case of gadolinium-enhanced computed tomographic aortography (CTA) for suspected thoracic dissection is reported. Aortic enhancement was sufficient for confident exclusion of an intimal flap. The findings ...

OBJECTIVES: To present electronic videoendoscopy of the larynx with digital image processing and to discuss this endoscopic technique from the standpoint of diagnostic usefulness of laryngeal lesions. STUDY DESIGN: Electronic videoendoscopic evaluation of laryngeal lesions with digital image processing. METHODS: Seventy patients underwent electronic videoendoscopy without digital image processing and, ...

To compare conventional ultrasonography (US) and magnetic resonance (MR) imaging with contrast agent-enhanced US for detection of VX-2 liver tumors in rabbits. Conventional gray-scale liver US was performed in 65 rabbits, 38 of which had VX-2 hepatic tumor implants. Twenty minutes after contrast agent injection, gray-scale pulse-inversion harmonic US images ...