A method was devised for obtaining dynamic contrast-enhanced T1-weighted and relaxation rate (delta R2*) images simultaneously to evaluate regional hemodynamics of the brain tumors. On a 1.5-T MR system, dual dynamic contrast-enhanced images were obtained using a gradient echo (dual echo fast field echo) pulse sequence with the keyhole technique to improve temporal and spatial resolution during a rapid bolus injection of gadopentetate dimeglumine. The dynamic T1 contrast images were obtained from the first echo: moreover. integral delta R2*dt values were calculated from the first and the second echo images. The dynamic T1 contrast images provided information about characteristic enhancement pattern (vascularization and disruption of blood-brain barrier), and the integral delta R2*dt values provided a map of regional blood pool in tumor site, peritumoral edema, and other surrounding regions of the brain. The ability to obtain dynamic contrast-enhanced T1 contrast and delta R2* imaging at the same time allows optimization of the advantages of each and thereby more information about the microvascular circulation of the brain lesions.

Brain↗

PubMedDate not supplied

Atypical exocrine and endocrine pancreatic tumors (anaplastic, small cell, and giant cell types): CT and pathologic features in 14 patients.

BACKGROUND: Our purpose was to review a series of 14 patients with atypical exocrine and endocrine pancreatic tumors to derive characteristic computed tomographic and pathologic features that might allow better diagnosis, categorization, and management of these patients. METHODS: Medical records from several university medical centers were reviewed retrospectively. RESULTS: We identified three separate types of pancreatic tumors that had substantially different morphologic and prognostic features. Among these rare tumors, anaplastic carcinoma was the most common (nine of 14 cases), and these tumors were large, partly necrotic, locally invasive, and invariably metastatic (lymph nodes and/or liver) at the time of diagnosis. Three patients with poorly differentiated (small cell) carcinoma had a confluent pancreatic mass and lymphadenopathy but no ductal obstruction, closely resembling lymphoma or metastatic disease. Two patients with giant cell (osteoclastlike) carcinoma had a large, encapsulated multicystic tumor with hemorrhage, and these tumors were resectable for cure. CONCLUSION: Although a specific diagnosis may not be possible in some cases, we believe that knowledge of certain pathologic and computed tomographic features should lead to optimal diagnosis, therapy, and prognosis.

Carcinoma↗

PubMedDate not supplied

Direct coronal CT scanning for the body.

A direct coronal CT scanning technique for the trunk, named "Quasi-Coronal" CT, is presented and its usefulness demonstrated with clinical examples. Patients are placed in the lateral position on a wide plate laid on the scanner bed and instructed to assume various special postures. An important concept of this technique is to obtain the tomograms in which target organs with predominant longitudinal orientation are directly imaged in the coronal plane. An analysis of artifacts due to "Out of Field" objects is presented. When properly performed, "Quasi-Coronal" CT can provide useful additional information, despite having some limitations.

Aged↗

PubMedDate not supplied

Calcific tendinitis of the gluteus maximus tendon with cortical bone erosion: CT findings.

A case of calcific tendinitis of the gluteus maximus tendon with cortical erosion is presented. Roentgenography demonstrated calcification on the posterior surface of the proximal femur. Computed tomography showed flame-like appearance of calcific tendinitis and bone erosion. Magnetic resonance imaging showed minimal inflammatory reaction around the lesion.

Bone Resorption↗

PubMedDate not supplied

Diffuse pulmonary lesions in early phase Takayasu arteritis predominantly involving pulmonary artery.

We report a case of early phase Takayasu arteritis that predominantly involved the pulmonary arteries and had, along with expected radiographic findings, the unusual pattern of diffuse pulmonary parenchymal lesions on CT. We suggest that this finding may be an additional feature in early phase Takayasu arteritis and need not require investigation for an additional diagnosis.

Aorta↗

PubMedDate not supplied

Contribution of a peroxide adduct of copper(II)-peptide complex to modify the secondary structure of albumin.

We have found that copper(II) compounds containing a peptide group in the chelate exhibit high activity for modification or degradation of albumin in the presence of hydrogen peroxide, whereas no activity was detected for the copper(II) compounds without an amide-group. It is suggested that presence of the amide-group in the ligand may play an important role in the formation of a peroxide adduct and in activation of the peroxide ion, leading to cleavage of the peptide bond of a neighboring protein. It is implied that conversion of normal cellular prion protein PrPC into a disease-causing isoform, PrPSc is attributed to the activated peroxide ion coordinated to a copper(II) captured in the NH2-terminal domain of the PrPC.

Carbonic Anhydrases↗

PubMedDate not supplied

A case of ganglioneuroma with fatty replacement: CT and MRI findings.

We report a rare case of posterior mediastinal ganglioneuroma with fatty replacement together with its appearance on CT and MRI and suggest adding this entity to the differential diagnosis of fat-containing posterior mediastinal masses.

Adipose Tissue↗

PubMedDate not supplied

A case of thymic cyst associated with thymoma and intracystic dissemination.

We report a rare case of anterior mediastinal thymic cyst together with a thymoma and its intracystic dissemination. More attention should be given to intramural nodules, especially in patients with an anterior mediastinal thin wall cystic lesion.

Contrast Media↗

PubMedDate not supplied

A case of right-sided aortic arch with isolation of the left subclavian artery: CT findings.

We report a case of right-sided aortic arch with isolation of the left subclavian artery diagnosed using computed tomography (CT). This was a rare type in which the left subclavian artery, originating from the pulmonary artery via the arterial duct, was isolated after closure of the ductus. Collateral circulation was considered to be obtained mainly from the left intercostal artery via the costocervical trunk through the supreme intercostal artery.

Aorta, Thoracic↗