Case report 852. Periosteal osteosarcoma of femur.
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Adult↗
Biomedical subjects
E K Fishman
Publications and source records attributed to E K Fishman.
Case report 854: Eosinophilic granuloma.
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Child, Preschool↗
Digital video applications in radiologic education: theory, technique, and applications.
Computer-assisted instruction (CAI) has great potential in medical education. The recent explosion of multimedia platforms provides an environment for the seemless integration of text, images, and sound into a single program. This article discusses the role of digital video in the current educational environment as well as its future potential. An indepth review of the technical decisions of this new technology is also presented.
Computer-Assisted Instruction↗
Two-dimensional and three-dimensional imaging of the in vivo lung: combining spiral computed tomography with multiplanar and volumetric rendering techniques.
We applied multiplanar techniques and a modified version of our volumetric rendering program for three-dimensional imaging to single-breath hold spiral computed tomography (CT) datasets to generate two- and three-dimensional (2-D and 3-D) images of the in vivo lung. We report details of the combined 2-D/3-D spiral CT technique along with three representative cases from our initial experience.
Adult↗
Intrahepatic cholangiocarcinoma: findings on spiral CT during arterial portography.
To attempt to determine the characteristic imaging features of intrahepatic cholangiocarcinoma on spiral CT during arterial portography (CTAP), spiral CTAP examinations of 17 patients with pathologically confirmed intrahepatic cholangiocarcinoma were reviewed in consensus by three radiologists. The diameter of the tumors ranged from 1 to 12 cm (mean diameter, 6.6 cm). All tumors (100%) were hypoattenuating masses on spiral CTAP. In 11 cases, the tumor was homogeneous in attenuation (65%). Tumor margins were smooth and regular in 11 cases (65%). Vascular invasion was found in 14 cases (82%). Intrahepatic bile duct dilatation was present in seven cases (41%). This review shows that intrahepatic cholangiocarcinoma is associated with a constellation of findings on spiral CTAP. The presence of a low attenuation homogeneous intrahepatic mass with vascular invasion and intrahepatic bile duct dilatation on spiral CTAP images should raise the possibility of intrahepatic cholangiocarcinoma. However, these findings can be associated with other types of primary and secondary malignant hepatic tumors.
Adult↗
Pictorial review: computed tomography of renal inflammatory disease.
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Abscess↗
Spiral CT of the liver: current applications.
Spiral CT allows rapid imaging of the liver resulting in improved contrast dynamics compared with conventional CT techniques. Improved lesion detection has been shown with spiral CT by using overlapping reconstruction intervals and by eliminating respiratory misregistration. Vascular and parenchymal abnormalities, including portal venous thrombosis or cirrhosis with development of collateral vessels, are readily appreciated using spiral technique. Combining spiral CT and portography enhances lesion detection by maintaining high levels of hepatic contrast enhancement for the duration of the liver scan.
Humans↗
Spiral CT of the pancreas.
Spiral CT technology now represents the gold standard in the evaluation of known or suspected pancreatic pathology. For both neoplastic and inflammatory diseases of the pancreas, spiral CT offers many unique advantages over conventional dynamic CT scanning. This article reviews the basic technique and applications of spiral CT in evaluation of the pancreas, with emphasis on its specific advantages.
Humans↗
Dose requirements for a nonionic contrast agent for spiral computed tomography of the liver in rabbits.
RATIONALE AND OBJECTIVES: The purpose of this study was to determine the relationship between intravenous dose of a nonionic contrast agent and hepatic enhancement using spiral computed tomography. METHODS: The enhancement of the liver, hepatic vein, inferior vena cava, and aorta was evaluated in the New Zealand male rabbit after intravenous injection of iohexol, 300 mg iodine (I)/mL, at 2 mL/sec. Spiral computed tomography scans of 10 animals were evaluated at each of nine different contrast doses (857, 771, 686, 600, 514, 429, 343, 257, and 171 mg I/kg) for a total of 90 spiral scans. RESULTS: Hepatic attenuation was linearly proportional to the contrast dose over the range of doses examined. The average change in attenuation of the liver from the first to the last scanned portion of the liver ranged from 0 to 7 Hounsfield Units (HU) (standard deviation ranging from 4 to 11 HU). Hepatic venous enhancement was greater than that of the liver for doses greater than 171 mg I/mL. The aortocaval difference in enhancement was greater than 10 HU in all cases. CONCLUSION: A dose of 429 mg I/kg, providing an average hepatic enhancement greater than 30 HU, is predicted to be the lower dose limit for hepatic parenchymal enhancement using spiral computed tomography.
Animals↗
Spiral computed tomography arterial portography with three-dimensional volumetric rendering for oncologic surgery planning. A retrospective analysis.
RATIONALE AND OBJECTIVES: Surgical resection of metastatic neoplasms of the liver can prolong survival of patients. The decision to resect a tumor depends to a great extent on the location of lesions relative to hepatic vasculature. Spiral computed tomography arterial portography (SCTAP) is an excellent technique for preoperative localization of tumors. The addition of three-dimensional rendering of image data sets should enhance the efficiency and accuracy of the interpretation of these data by the surgeon. METHODS: Fourteen patients with surgically and pathologically proven solitary and multiple metastatic hepatic neoplasms underwent SCTAP: Volume data sets thus derived were used to produce life-like three-dimensional animated images through a process known as volumetric rendering. These images were presented to the surgeon, who evaluated them based on several criteria. RESULTS: Accurate and clinically useful images were produced routinely in 13 of 14 patients. CONCLUSIONS: Clinical utility of three-dimensional rendering of SCTAP data sets for preoperative localization of hepatic lesions has been shown retrospectively. A larger, prospective study is suggested to demonstrate the accuracy and efficacy of the technique.
Adult↗
Skeletal complications of radiation therapy.
Radiation therapy is an important modality in the treatment of a wide variety of neoplasms. Skeletal complications of radiation therapy include alterations in bone growth, radiation osteitis with secondary stress fractures, and radiation-induced sarcoma. Routine follow-up of patients who are asymptomatic may show radiation changes that must be differentiated from recurrent disease. In symptomatic patients who are examined for metastatic disease, imaging findings may suggest stress fractures related to prior radiation therapy or, rarely, radiation-induced tumors. Correlation of the clinical presentation, radiation ports, and radiologic findings will often help in the differential diagnosis in these patients.
Adult↗
Imaging of the spleen: CT with supplemental MR examination.
Splenic lesions tend to be small or infiltrating and vary in size and configuration, making detection difficult, particularly without use of an organ-specific contrast agent. The authors present a series of selected cases to show the value of computed tomography (CT) and magnetic resonance (MR) imaging in depiction of splenic disease. Six major categories are presented: (a) inflammatory disease, (b) splenic cysts, (c) infarction, (d) nonneoplastic and noninfectious diffuse splenic disease, (e) benign tumors, and (f) malignant tumors. CT attenuation of splenic tissue is homogeneous, typically measuring 40-60 HU on non-contrast material-enhanced scans. Splenic attenuation is normally 5-10 HU less than that of liver, a standard of reference used in evaluation of either hepatic or splenic disease. On T1-weighted MR images, the normal signal intensity of the spleen is less than that of hepatic tissue and slightly greater than that of muscle. On T2-weighted images, the spleen shows higher signal intensity, appearing brighter than the liver. CT is currently the choice for evaluation of the spleen; however, MR imaging may be increasingly used as newer pulse sequences and organ-specific contrast agents are developed.
Abscess↗
CT and MR imaging evaluation of chest wall disorders.
Computed tomography (CT) and magnetic resonance (MR) imaging have complementary roles in the evaluation of chest wall disorders, which include mesenchymal tumors, primary and secondary malignancies, and inflammatory and infectious diseases. Important anatomic regions of the chest wall to evaluate on axial images include the supraclavicular fossa, axilla, and parasternal-internal mammary zone. For diagnosis of a suspected lipoma, CT is faster and less expensive; however, MR imaging may better delineate the extent of more invasive tumors if surgery is planned. MR imaging best depicts intramuscular neurofibromas and soft-tissue, intraspinal, and marrow involvement of neurogenic tumors, although CT more readily shows small calcifications and bone destruction. For diagnosis of lymphangioma, particularly when intravenous contrast material cannot be given for CT, MR imaging is preferred. CT more accurately demonstrates cortical bone destruction from masses arising in the ribs, but MR imaging is better for depicting infiltration of bone marrow and the extent of soft-tissue involvement. MR imaging displays Pancoast tumors and chest wall invasion from lung cancer better than CT because of its multiplanar capability and depiction of subtle differences in soft-tissue contrast. Both CT and MR imaging are helpful in evaluating infections, with CT being used to reveal bone destruction and to guide aspiration and drainage and MR imaging demonstrating soft-tissue involvement. The choice of technique, CT versus MR imaging, often depends on the specific clinical question to be addressed.
Humans↗
CT evaluation of the anterior mediastinum: spectrum of disease.
Computed tomography (CT) is the study of choice for evaluating disease in the anterior mediastinum. Mediastinal CT is usually performed with intravenously administered contrast material, and spiral CT is the preferred technique for evaluating a mediastinal mass. CT demonstrates thymic hyperplasia and thymic cysts and can help differentiate thymoma and thymic Hodgkin lymphoma. It is also useful in staging Hodgkin lymphoma and non-Hodgkin lymphoma. In thyroid malignancy, CT can depict mediastinal extension and lymphadenopathy; it also allows detection of goiter and ectopic parathyroid glands. Germ cell tumors such as teratoma and seminoma have characteristic appearances at CT. CT can also demonstrate miscellaneous mediastinal masses, such as lymphangioma, hematoma, those due to fibrosing mediastinitis, and pericardial cysts. Adenopathy due to tuberculosis or sarcoidosis is evident at CT, as is osteomyelitis due to a postsurgical abscess. Finally, CT features can suggest the pathologic origin of metastasis in the anterior mediastinum.
Adult↗
Interactive multimedia program for imaging the spleen: concept, design, and development.
The authors present some of the decision making and design goals that guided the development of computer-based educational programs, specifically a module to teach the role of computed tomography in detection and evaluation of splenic disease. One goal was that the program would take advantage of the computer yet allow users to recognize or learn quickly the techniques used to navigate through the program. A game interface was chosen as a means to aid retention of the material being taught, as well as to make use of the module enjoyable. The structure used to present the program content was based on the common means by which radiology has traditionally been taught. The four sections of the module consist of the slide lecture, traditional text, a quiz, and teaching files. Each question in the quiz section is linked to the relevant text section for review, and the teaching file section can be used as a self-test by hiding the text and diagnosis fields. Computer-based educational programs are an important resource for residents and practicing professionals, and they will continue to evolve with developments in technology. However, it should be the goal of all new projects to find a balance of form, in which the value of traditional teaching methods can be preserved with the maximum opportunity for innovation.
CD-ROM↗
Primary malignant neoplasms of the liver: detection with helical CT during arterial portography.
PURPOSE: To assess the sensitivity of helical computed tomography during arterial portography (CTAP) in the detection of primary malignant neoplasms of the liver. MATERIALS AND METHODS: Preoperative helical CTAP examinations of 19 patients (13 men, six women, aged 33-78 years) with primary malignant neoplasms of the liver (hepatoma, n = 12; cholangiocarcinoma, n = 4; angiosarcoma, n = 1; biliary cystadenoma, n = 1; hepatoblastoma, n = 1) were retrospectively reviewed by three radiologists. Imaging findings were correlated with intraoperative and pathologic findings. RESULTS: A total of 29 separate malignant neoplastic nodules (mean diameter, 6.6 cm) were identified in the resected specimens (16 patients) or intraoperatively in three patients. The overall sensitivity of helical CTAP was 72%; for neoplasms with a diameter less than 1.0 cm, 25%; for neoplasms 1.1-2.0 cm and 2.1-4.0 cm, 25% and 67%, respectively; and for neoplasms over 4.0 cm, 100%. CONCLUSION: The overall sensitivity of helical CTAP in the preoperative detection of primary malignant hepatic neoplasms is low.
Adult↗
Hepatic metastases from colorectal cancer: detection and false-positive findings with helical CT during arterial portography.
PURPOSE: To determine the sensitivity and false-positive rate of helical computed tomography during arterial portography (CTAP) in the detection of hepatic metastases from colorectal cancer. MATERIALS AND METHODS: Preoperative helical CTAP was performed to examine 23 patients (10 men and 13 women, aged 43-77 years [mean, 63 years]) who later underwent surgical tumor resection. Imaging findings were retrospectively reviewed by two radiologists and were correlated with intraoperative and histologic findings. RESULTS: Helical CTAP demonstrated 33 of 35 metastases, with diameters of 4-95 mm, that were identified in resected specimens (sensitivity, 94%). The two metastases not demonstrated were 4 and 5 mm in diameter. Five false-positive lesions were found in four patients, yielding a false-positive rate of 17% by patient analysis and 13% by lesion analysis. CONCLUSION: The sensitivity of helical CTAP in the preoperative detection of hepatic metastases is high, and its false-positive rate compares favorably with that of conventional CTAP, but future comparative studies are needed to determine which is the better modality.
Colorectal Neoplasms↗
CT of intraabdominal desmoid tumors: is the tumor different in patients with Gardner's disease?
OBJECTIVE: A retrospective study of abdominal CT scans of patients with proved intraabdominal desmoid tumors was done to determine if any objective characteristics exist to differentiate desmoids related to Gardner's syndrome from isolated desmoids. Because the desmoid tumors of Gardner's syndrome can predate the diagnosis of Gardner's syndrome, it would be helpful to know which patients with desmoids need careful follow-up studies as well as initial workup for Gardner's syndrome and all its ramifications. Also, it would be important to differentiate benign from malignant desmoids associated with Gardner's syndrome. It was hoped that the location, enhancement characteristics, and/or the presence or absence of infiltration might be of value. We were interested in noting if, over time, the growth characteristics of desmoids found in Gardner's syndrome were different from those of isolated desmoids. MATERIALS AND METHODS: We reviewed 101 abdominal CT scans obtained in 23 patients during a 13-year period. Forty desmoid tumors were intraabdominal, including 30 lesions associated with Gardner's syndrome in 13 patients and 10 desmoids of the idiopathic form in 10 patients. These tumors were studied to define location; whether they were single or multiple; and whether they had any specific CT characteristics regarding margins, attenuation numbers, or contrast enhancement. RESULTS: Desmoid tumors associated with Gardner's syndrome were more likely to be multiple (38%, five of 13 patients) and to involve the mesentery (60%, 18 of 30 tumors) and the abdominal wall (40%, 12 of 30 tumors), whereas isolated desmoid tumors were singular (all 10 patients) and were located in the retroperitoneum (six cases), pelvis (three), and anterior wall (one). Desmoids related to Gardner's syndrome also tended to be smaller (mean diameter, 4.8 cm) than idiopathic desmoids (mean diameter, 13.8 cm). No differentiating CT characteristics regarding margins, attenuation numbers, or response to contrast material were ascertained. Ten new lesions (seven intraabdominal, three mesenteric) developed in three patients with Gardner's syndrome, whereas no new intraabdominal lesions developed in patients with idiopathic desmoids. Follow-up data on 16 surgically resected desmoids in nine patients (seven with Gardner's syndrome and two with isolated desmoids) revealed seven local recurrences (two in the two patients with isolated desmoids and five in two patients with Gardner's syndrome). CONCLUSION: No CT characteristics, such as attenuation values, margins, and response to the contrast material, were found that would enable differentiation between isolated intraabdominal desmoids and those associated with Gardner's disease. Desmoid tumors associated with Gardner's syndrome tend to occur in the mesentery and abdominal wall, whereas isolated desmoids involve the retroperitoneum and pelvis. When studying CT scans obtained over time, new lesions were noted to develop in a few of the patients with Gardner's syndrome (three of 13), whereas no new lesions were found in patients with isolated desmoids.
Adult↗