The Journal of computed tomography最新文献

We have reviewed our continued experience with computed tomography guided freehand percutaneous brain biopsy using a needle guide sheath of our own devising. The guide sheath is equipped with small metallic marker beads and throws no artifacts. It is useful in demonstrating the exact tip of the guide biopsy sheath in relation to the wall of the intracerebral lesion. The deforming response of the target lesion wall to the guide sheath and the biopsy needle is easily seen using our technique and is highly correlated to obtaining a satisfactory pathologic specimen. Combination of this guide sheath with a suitable computed tomography compatible head frame may represent a highly accurate and reliable but relatively simple guidance system.

Interfacing of the lung with the mediastinum produces a number of mediastinal lines including those due to the innominate veins, left subclavian artery, paratracheal stripe, both anterior and posterior junction lines, the azygo-esophageal recess, descending aorta and paraspinal lines.

Displacement or absence of one or more of these lines may be due to an abnormality of mediastinal contour or may indicate a mediastinal mass, but can occur in normal subjects.

Correlative findings between chest radiography and chest computed tomography in 50 normal subjects illustrate the variable nature of these lines.

Computed tomography and magnetic resonance imaging of a malignant hemangiopericytoma in a 58-year-old woman are described. The tumor was initially found in the abdomen and resected 34 years ago, but recurred 18 years later, followed by repeated recurrence and eventually metastasis to the lung and then to the liver. The lung nodules were round or oval, homogeneous, and well circumscribed while the massive tumor in the right lobe of the liver was poorly delineated with irregular areas of cystic necrosis. With proper setting of the repetition time and echo delay, the metastatic tumor became distinct from the uninvolved hepatic tissue on magnetic resonance imaging. In this case computed tomography and magnetic resonance imaging were complementary in evaluation of such a tumor.

Numerous reports of complications of central venous catheters have appeared in the literature. Most often these complications are diagnosed by plain or interventional radiography. Two cases are reported in which computed tomography was instrumental in diagnosing an abnormality that was not obvious on conventional radiography. This report demonstrates the value of this noninvasive technique for rapid and accurate evaluation.

Giant pseudopolyp formation is an uncommon but well-recognized complication of Crohn's disease. The computed tomography manifestations are described for the first time. Correlation with air-contrast barium enema, as well as colonoscopy, is presented. Computed tomography can be a useful adjunct in the diagnosis as well as management of this disease entity.

In the course of examining 1,000 patients with various neurological complaints, 17 were found to have abnormalities in the region of the pineal gland. Fourteen had no hydrocephalus or symptoms referable to the region of the midbrain but a well-defined region of high signal on T2 weighted images was demonstrated on magnetic resonance imaging. The other three patients proved to have pineal tumors. All patients had computed tomography examinations prior to magnetic resonance imaging. We believe that the pineal lesion in the 14 asymptomatic patients is a benign cyst not previously reported prior to the advent of magnetic resonance imaging. These benign lesions should be kept in mind in evaluating masses of the pineal region.

Wilms tumor, the most common solid childhood malignancy, is frequently associated with pulmonary metastases, while hepatic metastases occur less frequently. Metastases to the lower lobes of the lungs, when deep in the costophrenic sulcus, may simulate an intraabdominal mass. The differentiation of these lesions is important both diagnostically and therapeutically. Three cases are presented in whom pulmonary sulcus metastases simulated abdominal lesions on computed tomography and could not be clearly localized as thoracic in origin on liver/spleen scintigraphy. Ultrasound evaluation was the most useful; however, integration with other imaging techniques was necessary to correctly identify these lesions as being of pulmonary origin.

Computed tomography finding in a 17-year-old girl with association of the Mayer-Rokitansky-Kuster-Hauser syndrome and endometriosis is presented.

A patient who presented with coexistent xanthogranulomatous pyelonephritis and renal cell carcinoma is reported. Nine previously reported cases are reviewed and the possible significance of this association is discussed.

Sixty-five mass lesions of parotid origin were evaluated using thin-section high-resolution computed tomography to ascertain histologic specificity. All patients were studied after infusion of intravenous contrast media. Factors judged included the extent of glandular involvement, invasion of adjacent soft tissues, degree of postcontrast computed tomography density (relative to muscle), and the presence of calcification.