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At least 109 records · Page 6Linked to original sources
PubMed1984

Abnormal fat: a useful marker of intra-abdominal disease at computed tomography.

Computed tomography (CT) gives unique information about the margins of the intra-abdominal organs and the intervening fat and fascial planes. Not infrequently, these planes appear abnormal without any visible underlying cause. We present 85 patients in whom such an abnormality was shown. Although the appearances are non-specific, tumour infiltration was the most common cause (57 (70%) out of 82 where the cause is known). Infection, secondary effects of pancreatitis, granulomatous disease, haemorrhage, early ascites or oedema and the effects of radiotherapy should all be considered in the differential diagnosis.

Adipose Tissue↗
PubMed1987

Extending the search pattern in computed tomography.

Computed tomography has made new demands upon the traditional search patterns used by radiologists. These demands reflect not only the novel orientation of the images, being a series of axial slices, but also increased detail shown on the films. The scope for macropathological correlation with the image has also increased. Review areas are suggested which are pertinent to interpretation of the scans.

Humans↗
PubMed1988

Demonstration of a tracheal bronchus by computed tomography.

Computed tomography (CT) demonstrated a tracheal bronchus in a young child as well as the associated cystic disease of the right lung. Confirmation of the anatomical bronchial variant was obtained later when the cystic lesion was infected with aspergillus and surgically removed.

Aspergillosis↗
PubMed1988

The anatomy and pathology of the brachial plexus as demonstrated by computed tomography.

Computed tomography (CT) scanning can demonstrate a wide range of abnormalities affecting both the brachial plexus and the surrounding structures. Narrow section (4 mm) CT was used with bolus intravenous enhancement to examine the root of the neck and axilla in 62 patients with cancer, many of whom had symptoms of brachial plexus neuropathy. The normal anatomy of the plexus and its relations are described and illustrated. Examples of pathological changes caused by tumour and irradiation are also presented. The narrow scanning width (4 mm) is needed as the details sought are small and will be missed on thicker slice widths, particularly the changes of fibrosis in the upper axilla. Injection of intravenous contrast medium is essential for identifying the vascular structures which are used to locate the brachial plexus, especially when disease processes and post-irradiation fibrosis have destroyed the tissue planes.

Axilla↗
PubMed2003

Triplane fractures of the distal tibia requiring open reduction and internal fixation. Pre-operative planning using computed tomography.

Computed tomography (CT) of triplane fractures provides useful information not available on conventional radiographs. Knowledge of the size and position of displaced fragments, the location of the intra-articular fracture and any associated articular incongruency is useful when undertaking pre-operative planning.A postal survey of surgeons revealed only 38% always requested CT scans before undertaking open reduction and internal fixation of displaced triplane fractures. Examples of the usefulness of CT scans in pre-operative planning is presented in two cases.

Fracture Fixation, Internal↗
PubMed1981

Diagnosis of dissecting aortic aneurysm by computed tomography.

Computed tomography (CT) of the torso combined with simultaneous intravenous bolus injection of contrast media was used in sixteen patients suspected of having dissected their aorta. All patients had subsequent correlative percutaneous aortography within 24 h of the CT examination. Four patients proved to be normal, one had an aneurysm of the thoracic aorta, and eleven had aortic dissection (five type I, six type III dissection). All eleven patients with aortic dissections were diagnosed by CT and angiography; nine had spontaneous dissections and two had iatrogenic injuries to the aorta. Limitations of this imaging procedure include; inability to detect aortic valvular dysfunction and failure to provide an adequate perspective of aortic branch involvement. Potential benefits include: avoidance of aortogram in some cases, relative non-invasiveness, rapidity and ease of procedure, and less expense, radiation, contrast media, and discomfort to the patient. Early experience with CT-enhancement technique has reliably demonstrated normal as well as abnormal aortic wall morphology. It may have a place as an alternative to the conventional aortogram.

Adult↗
PubMed2002

The unilateral opaque maxillary sinus on computed tomography.

Computed tomography (CT) is the imaging method of choice for conditions that affect the paranasal sinuses. We reviewed all paranasal CT scans in the ear nose and throat (ENT) and maxillofacial surgery departments in 1 year. Of these 372 scans, unilateral opacity of the maxillary sinus was seen in 20 cases. Neoplastic disease was diagnosed in six of these, four of which were malignant. We describe the cases of neoplastic disease, particularly features of the history, examination, and scans that should alert the clinician to the possibility of sinister pathology. We emphasise the importance of nasendoscopic examination in the accurate assessment of sinonasal disease.

Adult↗
PubMed1984

The relative proportions of fat, muscle and bone in the normal human forearm as determined by computed tomography.

Computed tomography has been used to establish the proportions of fat, muscle and bone present in the normal human forearm. Subjects were healthy young volunteers, eight males and eight females. A series of six cross-sectional scans at right angles to the long axis of the forearm was obtained, the scans being made at equidistant intervals between the olecranon process and the ulnar styloid. The volumes occupied by fat, muscle and bone were calculated for the complete forearm. Total forearm volume calculated by this method agreed closely with that measured by water displacement. For the male subjects, forearm composition was 72.1 +/- 4.4% muscle (mean +/- SD), 15.0 +/- 5.3% fat and 12.9 +/- 1.2% bone. Female forearms had less muscle (P less than 0.001) and more fat (P less than 0.001) than those of the male subjects: 58.5 +/- 4.0% muscle, 29.3 +/- 5.0% fat and 12.3 +/- 1.4% bone. Forearm muscle volume was significantly correlated (r = 0.75; P less than 0.05) with lean body mass in the male subjects; the range of values for lean body mass in the female subjects was too small to permit calculation of the equivalent relationship. Forearm fat content, as a percentage of total volume, was proportional to whole body fat content as estimated from skinfold thickness (males, r = 0.84; P less than 0.01; females, r = 0.77; P less than 0.05). These relationships enable estimates of the volumes of forearm tissue components to be derived from anthropometric measurements.

Adipose Tissue↗
PubMed1998

Densities and sizes of main masticatory muscles in patients with internal derangements of temporomandibular joint obtained by computed tomography.

Computed tomography (CT), due to its excellent resolution capacity, is a suitable method to examine the soft and bony structures of the masticatory system. The aim of this study was to compare densities and sizes of the masseter and medial and lateral pterygoid muscles obtained by CT between the symptomatic and asymptomatic side in patients with internal derangement of the temporomandibular joint (TMJ). The aim was also to correlate these variables to sex and age, duration of the symptoms, diagnosis and dentition. The material consisted of 33 patients (26 women, 7 men, mean age 37 years, range 14-74 years) whose TMJs were examined by CT and whose coronal CT scans were available. Diagnosis in the symptomatic TMJ was confirmed in operation. No statistically significant difference was seen in mean densities and sizes of the masticatory muscles between the symptomatic and asymptomatic side. The duration of the symptoms, however, correlated positively to the density of the lateral pterygoid muscles in patients with complete dentition. The age of the patients in this group correlated negatively to the size of the masseter muscles. It can be concluded that patients with internal derangements of TMJ with a long duration of symptoms have structural changes in their masticatory muscles which are detectable by CT.

Adolescent↗
PubMed1988

[Malignant fibrous histiocytoma of soft tissue. Possibilities and limitations of computed tomography].

Computed tomography was performed in 27 patients with confirmed malignant fibrous histiocytoma of the soft tissue. Compared with the CT results obtained in other tumours of the soft tissues. CT accuracy in malignant fibrous histiocytoma was only 74%. Non-typical attenuation values, diffuse tumour growth and non-typical contrast enhancement are discussed as reasons for the diagnostic understaging or overstaging of these soft tissue tumours. A higher accuracy was found on ultrasound examination with regard to tumour extension. Bone destruction was better visualised by CT. A base-line CT is recommended postoperatively for the earlier detection of recurrent tumours in further investigations.

Adult↗
PubMed1989

Endotheliomatous meningioma with coalescing microcysts, presenting as an hypodense lesion with ring enhancement on computed tomography.

Computed tomography (CT) revealed a hypodense intracranial tumour that showed a slight ring enhancement and a peripheral tumour nodule. Although this suggested a cystic astrocytoma, angiography identified a meningeal tumour. Microscopical examination demonstrated a cystic endotheliomatous meningioma. Neuropathological and intraoperative findings suggested that the meningioma was an intermediate form between the microcystic and macrocystic types, illustrating the evaluation from the former to the latter.

Cysts↗
PubMed1982

Assessment of abdominal fat content by computed tomography.

Computed tomography (CT) produces thin cross-sectional radiographs that may prove very useful in body composition research. CT images of the abdomen allow computerized measurement of total fat area, and also enable the differentiation of subcutaneous fat from intraabdominal fat. The preset investigation examines whether a single CT scan of the abdomen provides an accurate indication of overall abdominal adiposity. Graphs of measurements from seven sequential scans of the abdomen in eight patients showed that rankings of total abdominal area, total fat area, subcutaneous and intraabdominal fat area are relatively consistent no matter which abdominal level is chosen. Correlations of 0.89 to 0.99 between single scans and the average values for all scans show that a single CT image contains the same information on adiposity as a series of scans. These results suggest that future CT studies of body composition can limit radiation exposure by using single scans at different anatomical sites. If only a single scan at one site can be obtained, the level of the umbilicus may be the most useful, because it contains the largest percentage of fat in the body, and best allows differentiation of intraabdominal from subcutaneous fat.

Abdomen↗
PubMed1983

Age changes in body composition revealed by computed tomography.

Computed tomography scans were taken of 21 middle-aged men (M age 46.3 years) and 20 older men (M age 69.4 years) to measure differences in body composition with age. Overall, the older men weighed 8.2 kg less than the middle-aged men, and this difference was primarily the result of their having less lean tissue. Although fat mass was only slightly less in older men, there were clear distributional differences in fat between the age groups. Total abdomen fat area was similar in both groups, although the subcutaneous portion of the abdomen fat was less in the older men, and they had correspondingly greater intra-abdominal fat. Muscle areas of the leg and arm were significantly less in the older men, as were all lean tissues of the abdomen and chest. Analysis of fat accumulation between muscles of the abdomen and leg indicated fat infiltration into lean tissue in the older men. Causes of this apparent fat redistribution and lean body mass decline with age are presently unknown.

Adipose Tissue↗
PubMedDate not supplied

Factors affecting the measurement of size and CT number in computed tomography.

Computed tomography scanners may be used to make anatomic size measurement; however, manipulating the viewer controls (especially the window center) can have a significant influence on the apparent size of structures in the image. A special phantom was constructed to study the effect of window center adjustments on the apparent size of lone cylindrical objects (no variation within slice thickness) and also for spherical objects (maximum variation within slice thickness). Using this phantom, the authors were able to identify several commonly encountered situations in which both the apparent size and CT numbers may be seriously in error. It was found that for cylindrical objects larger than about one transverse resolution element and aligned with the scanner axis, CT numbers may be determined accurately; however, the apparent diameter changes by several millimeters as the window center setting is changed. CT numbers for spheres are inaccurate when the diameter is comparable to or less than the slice thickness and, as a result, diameters of spheres cannot be measured accurately with fixed window center settings. Diameters of spheres can be measured accurately (+/- 1 mm) if the sphere is centered in the slice and the full width at half maximum of the CT number profile is used.

Humans↗
PubMed1978

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↗
PubMed1979

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↗
PubMed1979

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↗