Appearance and distinguishing features of retroperitoneal calcifications at computed tomography.

Objectives: To describe the appearance of retroperitoneal calcifications seen at computed tomography (CT) and to investigate which CT features distinguish benign from malignant retroperitoneal calcifications.

Methods: We identified 25 patients with retroperitoneal calcifications by retrospective review of 39,931 abdominopelvic CT scans. Etiology of retroperitoneal calcifications was determined by examination of medical and histopathological records.

Dedicated extremity MR imaging of the foot and ankle.

The purpose of this review is to provide illustrative examples of diseases of the foot and ankle when imaged with a low-field MR imaging system. A retrospective review of 268 foot and ankle examinations, performed in our institution within the past 3 years with a 0.2-T (Artoscan Esaote, Genoa, Italy) dedicated extremity MR system was done.

Complex adnexal masses: detection and characterization with MR imaging--multivariate analysis.

Purpose: To evaluate the accuracy of magnetic resonance (MR) imaging in the detection and characterization of complex adnexal masses, with particular reference to the findings predictive of malignancy, role of gadolinium-enhanced contrast material, and observer variability.

Materials And Methods: Preoperative MR imaging of the pelvis was performed in 128 consecutive patients with clinically or ultrasonographically detected complex adnexal masses. Histopathologic examination demonstrated 187 masses, 96 of which were malignant.

Reperfused myocardial infarction as seen with use of necrosis-specific versus standard extracellular MR contrast media in rats.

Purpose: To measure the difference in size of reperfused myocardial infarction with necrosis-specific (bis-gadolinium-mesoporphyrin [hereafter, mesoporphyrin]) and standard extracellular (gadopentetate dimeglumine) magnetic resonance (MR) contrast media.

Materials And Methods: Echo-planar (for T1 measurement) and spin-echo (for infarction size) MR imaging were conducted in 32 rats subjected to reperfused reversible (n = 16) and irreversible (n = 16) myocardial injuries. All animals received gadopentetate dimeglumine 1 hour after reperfusion and underwent imaging.

Radiologic staging in patients with endometrial cancer: a meta-analysis.

Purpose: To apply a meta-analysis to compare the utility of computed tomography (CT), ultrasonography (US), and magnetic resonance (MR) imaging in staging endometrial cancer.

Materials And Methods: Data were obtained from a MEDLINE literature search and from manual reviews of article bibliographies. Articles were selected that included results in patients with proved endometrial cancer and imaging-histopathologic correlation and that presented data that allowed calculation of contingency tables.

The vascular vise causing TAPVR type I to radiographically mimic TAPVR type III.

A subtype of supracardiac total anomalous pulmonary venous return (TAPVR) consists of the vertical vein passing between the left pulmonary artery and the left mainstem bronchus resulting in relative obstruction to pulmonary venous return. This has been termed the vascular vise. In this situation, the supracardiac type of TAPVR (Type I) may mimic radiographically the infradiaphragmatic type (Type 3).

Cryptorchidism: strategies in detection.

Imaging evaluation of the patient with a non-palpable testis has evolved over recent decades. The rational explanation of imaging in these patients requires a clear understanding of the various causes of a non-palpable testis, and an appreciation of the utility and limitations of the available imaging modalities. This review describes the classification of non-palpable testis and discusses the role of modern imaging in evaluation.

Magnetic resonance imaging of the elbow.

Magnetic resonance imaging (MRI) provides useful information regarding the elbow joint. Many abnormalities seen in the elbow are a result of trauma, often from sports such as baseball and tennis. Elbow problems are frequently related to the medial tension-lateral compression phenomenon where repeated valgus stress produces flexor-pronator strain, ulnar collateral ligament sprain, ulnar traction spurring, and ulnar neuropathy.

Inhomogeneous lung attenuation at thin-section CT: diagnostic value of expiratory scans.

Purpose: To determine the utility of expiratory scans for diagnosis of inhomogeneous attenuation on thin-section computed tomographic (CT) scans.

Materials And Methods: On the basis of clinical information and pulmonary function test results, disease in 53 patients with inhomogeneous attenuation on inspiratory scans was classified into four groups--infiltrative, airway, vascular, or mixed. Without knowledge of the diagnosis, inhomogeneous attenuation was classified as (a) ground-glass opacity due to infiltrative disease, (b) mosaic perfusion due to airway disease, or (c) mosaic perfusion due to vascular disease, and the degree of confidence was indicated.

Ureteric bud remnant in two patients with renal agenesis: diagnosis by MRI.

The diagnosis of ureteral bud remnant associated with renal agenesis or dysplasia can be difficult. US and CT can be of limited value in these challenging congenital aberrations. When further evaluation is clinically required, MRI is recommended as a useful adjunct, as shown in the two cases discussed.

MRI of primary malignant cardiovascular tumors.

Purpose: The purpose of this study was to describe the MR features of primary malignant cardiac tumors, which may aid in differentiation from primary benign cardiac tumors.

Method: Seven patients with primary malignant cardiac tumor were imaged with MR. All studies were performed on a 1.

Assessing tumor angiogenesis using macromolecular MR imaging contrast media.

MRI enhanced with a macromolecular contrast medium (MMCM) has previously been shown to estimate tumor microvascular characteristics that correlate closely with histologic microvascular density, an established surrogate of tumor angiogenesis. A similar MMCM-enhanced MRI technique has now been used to investigate the acute tumor microvascular effects of antibody-mediated inhibition of vascular endothelial growth factor (VEGF), a well-studied and potent angiogenesis stimulator. Athymic rats xenografted with a human breast carcinoma (MDA-MB-435) were imaged after administration of albumin-gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA30) using a heavily T1-weighted three dimensional-spoiled gradient-refocused acquisition in a steady-state pulse sequence before and 24 hours after treatment with anti-VEGF antibody (single dose of 1 mg).

Task-induced asymmetry of the auditory evoked M100 neuromagnetic field elicited by speech sounds.

The auditory evoked neuromagnetic fields elicited by synthesized speech sounds (consonant-vowel syllables) were recorded in six subjects over the left and right temporal cortices using a 37-channel SQUID-based magnetometer. The latencies and amplitudes of the peaks of the M100 evoked responses were bilaterally symmetric for passively presented stimuli. In contrast, when subjects were asked to discriminate among the same syllabic stimuli, the amplitude of the M100 increased in the left and decreased in the right temporal cortices.

Vascular complications in lumbar disk surgery: report of four cases.

Vascular injuries in lumbar disk surgery, although rare, are serious complications which may be overlooked due to a broad range of clinical manifestations. It is important that surgeons and radiologists be aware of these potentially fatal complications and develop an appropriate symptom-based diagnostic paradigm. We reviewed 8099 consecutive cases of lumbar disk surgery, performed over a 14-year period at a single institution, for postoperative vascular complications.

MR imaging characterization of postischemic myocardial dysfunction ("stunned myocardium"): relationship between functional and perfusion abnormalities.

Stunned myocardium has been detected in patients treated successfully with thrombolytic agents. The hypothesis of this study was that fast gradient echo (GRE) imaging could be used to characterize the regional functional and perfusion abnormalities that are indicative of myocardial stunning. This study was designed to monitor and correlate the extent of wall thickness and perfusion abnormalities as determined by fast (segmented k space) cine and contrast enhanced GRE imaging, respectively.

Hormonal ablation of prostatic cancer: effects on prostate morphology, tumor detection, and staging by endorectal coil MR imaging.

Objective: The purpose of our study was to evaluate the effect of androgen deprivation therapy on the MR imaging findings of prostate gland anatomy and cancer pathology in men with prostatic cancer treated with hormonal ablation before radical prostatectomy.

Materials And Methods: Twenty-two patients (mean age, 66 years old) were divided into two groups: in group I (n=10), MR imaging studies were done before and after hormonal treatment; in group II (n=12), MR imaging studies were done only after hormonal treatment. MR imaging was performed on a 1.

Monitoring neovascularity as an indicator to response to chemotherapy in osteogenic and Ewing sarcoma using magnetic resonance angiography.

Histologic studies on resected specimen have shown that tumor neovascularity is related to prognosis and response to therapy in a variety of human neoplasms. In nine patients with osteogenic or Ewing sarcoma, we evaluated the use of magnetic resonance angiography (MRA) to assess neovascularity non-invasively in vivo and to monitor response to chemotherapy. Seven patients with osteosarcoma and two patients with Ewing sarcoma were studied before and after chemotherapy by MRA (2-D time-of-flight gradient-echo sequence, TR = 50 msec, TE = 9.