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At least 19 recordsLinked to original sources

[The demonstration and staging of bladder carcinoma. A comparative study between magnetic resonance tomography, computed tomography and radioimmunoscintigraphy].

The purpose of the present study was to compare the effectiveness of MRI, CT and radioimmunoscintigraphy in the staging and detection of bladder cancers in 28 patients. We distinguish two groups: Group I included the tumour stages CIS-T3A and the second group the deep infiltrative tumours T3B-T4. MRI was slightly superior to CT in respect of tumour staging (75% correct results as compared to 63%). No understaging occurred with MRI, whereas in 22% of the cases the stage of the tumour was underestimated using CT diagnostics. Overstaging occurred in 25% of the MRI and 15% of the CT-diagnostics, respectively. RIS cannot distinguish the tumour groups, and hence this method is useful only for the detection of the primary tumour and metastases. In 77% of cases the tumour was detected and in 15% the tumour could be safely excluded.

Adult

A comparison of gallium-67 single photon emission computed tomography and computed tomography in mediastinal Hodgkin's disease.

The role of gallium-67 single photon emission computed tomography (Ga-67 SPECT) in the assessment of mediastinal Hodgkin's disease was evaluated prospectively. Ga-67 SPECT and computed tomography (CT) were compared and correlated with clinical findings at initial presentation in 30 patients, 6 weeks after treatment, and 6 months later in 20 of the 30 patients. At initial presentation, active disease was detected on both imaging modalities on all occasions. 6 weeks after treatment CT showed residual mediastinal abnormality in 7 patients, whereas Ga-67 SPECT showed abnormal mediastinal tracer uptake in 3 patients. 6 months later CT showed residual mediastinal abnormality in 5 patients whereas all the Ga-67 SPECT studies were negative. Ga-67 SPECT imaging is a useful tool in assessing response to therapy in mediastinal Hodgkin's disease.

Adult

Evaluation of cholestatic jaundice by computed tomography.

Computed tomography of the abdomen can aid the clinician in distinguishing intrahepatic from extrahepatic causes of jaundice. Hepatobiliary and pancreatic disease may be clearly defined. The timing and selection of further diagnostic and surgical procedures can be guided by computed tomography and unnecessary operations and prolonged hospitalization can be reduced. Computed tomography of the abdomen should not be used as a screening procedure but should be used after simpler techniques fail to establish a definitive diagnosis.

Adolescent

The validity of criteria for the evaluation of cerebral atrophy by computed tomography.

Computed tomography of the brain was used in evaluating demented and nondemented elderly people. The incidence of convulutional atrophy and ventricular enlargement correlated well with pathologic and pneumoencephalographic examination of a similar population. Computed tomography also showed certain instances of dementia without atrophy and evidence of atrophy without dementia. The absence of brain atrophy in a demented patient should prompt a search for a potentially treatable cause of the dementia. The authors discuss criteria for diagnosing atrophy by computed tomography and conclude that, because of its noninvasive nature, it is a valuable aid in screening demented patients for treatable diseases.

Aged

Evaluation of abdominal abscess with computed tomography.

Computed tomography (CT) is valuable in providing a specific diagnosis of abdominal abscess and in determining its site and extent. Computed tomography is also capable of excluding an abscess with a high degree of certainty. In 31 of 34 patients with proven abdominal abscess, CT suggested the correct diagnosis and accurately defined the extent of involvement. In nine patients, the CT findings were specific for abscess. The CT appearance of abscess is diverse, largely depending on its location. The most common appearance is a low density mass often with higher density at the periphery. The presence of gas distributed within the mass or an extraalimentary air--fluid level allows an extremely confident diagnosis of abscess. Differential diagnostic possibilities are reviewed with emphasis on interpretive problems.

Abscess

Subependymal and intraventricular hemorrhage in neonates. Early diagnosis by computed tomography.

Computed tomography was used to evaluate subependymal and intraventricular hemorrhage in 11 formalin-fixed brains obtained at autopsy from newborn infants from a population with a known high incidence of cerebral hemorrhage. After scanning, the brains were step-sectioned at levels corresponding to those of the scans. Subependymal and/or intraventricular hemorrhage was demonstrated in 6 of the 11 brains. There was a very close correlation between the scan images and the gross pathological findings in the affected brains. The authors conclude that computed tomography is an accurate method for the diagnosis of neonatal cerebral hemorrhage.

Evaluation Studies as Topic

Historical experiments predating commercially available computed tomography.

Computed tomography (CT) was a revolution in radiology. Commercially available CT scanners appeared in 1972, a joint effort between the EMI Company, Atkinson Morley's Hospital, London and the Department of Health and Social Security (DHSS). The name of Sir Godfrey Hounsfield will always be associated with these developments. Like most developments in science the breakthrough came by standing on the shoulders of giants and many experiments can, with the curious wisdom of hindsight, be considered precursors to CT. Gabriel Frank's patent in 1940 showed apparatus for back-projection CT and Takahashi developed equipment in the 1940s for reconstructing from a sinogram; in both cases using an optical "computer". A medical CT scanner was reportedly constructed in 1957 in Kiev. Transmission CT was performed by Kuhl in 1965. Cormack built an experimental scanner in 1963. Oldendorf identified what was needed for successful CT as early as 1960. Throughout the 1960s a host of independent workers were busy on the mathematical problems of reconstructing from projections with both medical scanning and non-medical applications in mind. Experiments in early emission tomography influenced the development of CT. With imagination one can even see how close "classical" tomography, as started even before 1920, came to the realization of CT. The pioneering British radiographer Watson stands out from a galaxy of inventors. The lecture at Radiology and Oncology '91 in Brighton was a thumbnail sketch of the origins of radiological CT. A fuller story is told elsewhere (Webb, 1990).

History, 20th Century

Patterns of lesions of corpus callosum in inner cerebral trauma visualized by computed tomography.

Computed tomographic analysis of lesions of the corpus callosum in 13 patients with "inner cerebral trauma" showed significant congruence of linear translation of acceleration and the topographic distribution of such lesions. This congruence permits computed tomography to be used to reconstruct the course of linear translation and the site of the main blow, which can be important for forensic use. The findings of even a small lesion in the corpus callosum indicates the need for further investigation of other structures which are usually involved in inner cerebral trauma, such as the hippocampus and brain stem.

Adolescent

Measurement of lung density by computed tomography.

Computed tomography scanners can be calibrated to provide reproducible measurements for a quantitative analysis of lung density. Typical histograms for inspiration and expiration are presented. The reproducibility of the method is demonstrated as well as the limitations caused by artifacts and incomplete inspiration. This method is suggested for follow-up studies of patients with diseases affecting the entire lung. Early detection of interstitial lung disorders also seems possible.

Absorptiometry, Photon

Evaluation of laryngeal cartilages by computed tomography.

Computed tomography of the larynx was performed in 21 patients and 3 anatomic specimens for evaluation of laryngeal cancer. Special attention was directed to the appearance of the laryngeal cartilages in both the normal and abnormal examinations in order to establish criteria for cancerous invasion. The problem presented by the normal nonuniformity of density of the cartilages is discussed in detail.

Adult

Aberrant thyroid gland demonstrated by computed tomography.

Computed tomography (CT) demonstrated high attenuation values consistent with thyroid gland in scans of a patient with tumors in the base of the tongue and anterior median neck. Radioiodine scintigraphy revealed positive uptake in the same areas. This is an indication that CT attenuation values may be useful in the diagnosis of aberrant thyroid gland.

Adult

Acute isodense epidural hematoma on computed tomography.

Computed tomography (CT) has proven to be invaluable in the diagnosis of craniocerebral injuries. Acute epidural hematomas have been described as having a characteristic appearance on CT of a lenticular shaped area of blood density most commonly situated over the cerebral convexity. This case demonstrates an acute epidural hematoma that is essentially isodense with brain tissue.

Adult

Developmental changes in normal cranial measurements by computed tomography.

Computed tomography (CT) scans were examined for 89 selected patients in an attempt to establish normal values at various ages for longitudinal and transverse diameters of the brain, the greatest distance between the right and left sides of the anterior horn of the lateral ventricle, the width of the lateral ventricles in the region of the caudate nuclei, and the greatest width of the third ventricle. The patients' ages ranged from less than one year to over 40 years. These measurements and their ratios to one another are reported. The cerebral longitudinal fissure, Sylvian fissure and subarachnoid space were evident to some degree below the age of two years, especially below the age of one year, and again above the age of 40 years. The cortical sulcus was occasionally found to have a width of less than 1.9mm below the age of one year and above the age of 40 years.

Adolescent

Thigh composition in young and elderly men determined by computed tomography.

Computed tomography (CT) was used to quantify components of the thigh in young (n = 13) and elderly (n = 11) men. Cross-sectional areas (CSA) of the total limb, total muscle plus bone, quadriceps compartment, hamstring compartment and bone were measured at each of five scan sites along the length of the thigh. Non-muscle tissue (NMT) areas within the muscle compartments were measured using changes in density based on Hounsfield units. Skin plus subcutaneous fat areas and quadriceps and hamstring lean muscle areas were calculated by subtraction. Geometric formulae were used to calculate related volumes for each thigh component. Volumes were also predicted from regression equations employing thigh length and component CSA from single mid-limb CT scans. The results showed that while total thigh CSA was not different in elderly men, they had significantly smaller total muscle plus bone (13.0%), and quadriceps (26.4%), and hamstring (17.9%) muscle areas. The elderly men also had significantly greater CSA for skin plus subcutaneous fat (37.6%), and for NMT in the quadriceps (59.4%) and hamstring (127.3%) muscle compartments. These results suggest that comparisons of relative leg muscle strength between young and elderly men may be misleading due to the decrease in actual muscle tissue associated with ageing. Appropriate quantification of muscle size and CSA must be carried out before such comparisons can be meaningful.

Aging

Attenuation measurements of whole blood and blood fractions in computed tomography.

Computed tomography (CT) provides an extraordinarily effective means of diagnosing intracranial hemorrhages. Normal blood has a relatively high x-ray attenuation in the circulation and following extravasation, permitting the discrimination by CT of many pathologically enlarged vascular spaces containing circulating blood and/or blood clot (such as arteriovenous malformations and large aneurysms) in addition to recent hemorrhages, from continguous anatomical structures. To promote further understanding of the factors contributing to the attenuation of blood in normal and abnormal states. the attenuations of various preparations of whole blood and blood fractions were investigated in further detail.

Blood

Visualization of the thyroid gland with computed tomography.

Computed tomography of the neck will demonstrate the thyroid gland particularly well after contrast enhancement. Lucent nodules within the thyroid can be demonstrated, but the attenuation numbers are not reliable enough to distinguish cystic from solid lesions with current techniques because of partial volume effects and motion artifacts.

Humans

Demonstration of the superior ophthalmic vein by high resolution computed tomography.

Computed tomography has revolutionized the diagnosis of ophthalmologic and neuro-ophthalmologic disease. High resolution CT with thin-section techniques has made available the depiction of finer anatomic orbital detail and permits radiologic detection of more subtle lesions than was previously available. The display of normal-sized superior ophthalmic veins by CT is further evidence of the resolving power of the currently available machines. A segment of the superior ophthalmic vein was identified in 18 of 64 orbits examined by CT. Virtually the entire superior ophthalmic vein was identified in three orbits.

Arteriovenous Fistula