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PubMed1982

Volume determinations using computed tomography.

Computed tomography potentially offers the most accurate noninvasive means of estimating in vivo volumes. Contiguous 1-cm-thick CT scans were obtained through phantoms, dog kidneys in vivo, and human spleens before splenectomy. Cross-sectional areas were calculated for each individual scan and volumes then determined with each of four mathematical integration techniques. Volume estimations were compared to volumes determined by water displacement. The simplest, most practical means of calculating volumes, using the summation-of-areas technique with scans obtained at 2 cm intervals, was similar in accuracy to more complex methods. The mean percentage error of volume calculations using the sum-of-areas technique was 4.95% for five immobile phantoms, 3.86% for eight dog kidneys, 3.59% for eight human spleens in vivo at 1 cm scan spacing, and 3.65% for the same human spleens at 2 cm scan spacings. Difficulties in visual recognition and manual tracking of object boundaries seem to be more significant sources of error than patient-related factors.

Animals↗

PubMed1983

Cross-sectional shape of the child's trachea by computed tomography.

Computed tomographic scanning was used to investigate the shape in cross section of the lumen of the pediatric trachea. Seven children up to age 10 (mostly age 6 or older), six girls aged 10-19, and six boys aged 10-19 had scans of their tracheas, mostly during breath-holding not far from total lung capacity. At these ages and under these circumstances, the trachea may be slightly narrow just below the larynx, and it broadens just above its bifurcation. At other levels, it is only mildly or moderately off-circular although there are variations from patient to patient and from level to level. The severely off-circular shapes found by others during autopsies and computed tomography of the middle-aged and elderly were not detected in these children and adolescents. Under the circumstances of the study, there was little change in shape or size as the trachea passed from the neck into the chest, nor was there a consistent difference in tracheal shape between girls and boys.

Adolescent↗

PubMed1999

Caseous and infiltrative-caseous pneumonia in computed tomography.

Computer tomography (CT) imaging was made in 22 patients with acute tuberculosis--caseous and infiltrative-caseous pneumonia. CT role in detection of caseous changes, assessment of the extent and structure of caseosis, in differentiation of caseous and infiltrative-caseous pneumonia is described. CT is suggested to be an optimal roentgenological method of identifying caseous-pneumonic forms of tuberculosis.

Female↗

PubMedDate not supplied

Radiation dose in computed tomography.

Computed tomography exposes patients to higher radiation levels than most other imaging techniques. This article describes factors that affect radiation dose in CT, how CT dose is measured and methods to reduce the dose to patients and health care professionals.

Humans↗

PubMed2000

[Neonatal hydrocephalus-volume determinations using computed tomography].

Computed tomography potentially offers the most accurate noninvasive means of estimating in vivo volumes. Contiguous 5 and 10-mm-thick CT scans were obtained through phantom and neonatal cranium. Cross-sectional areas were calculated for each individual scan and volumes then determined with summation-of-areas technique. The indirect intracranial volume measurement technique was then used to compare hydrocephalic and non-hydrocephalic intracranial and ventricular volumes in nine neonates. Our findings show that intracranial volumes of hydrocephalic neonates with head circumference of more than 39 cm, have 1.97 times larger than control group. The ratios of lateral ventricle versus intracranial volume are 0.57 +/- 0.2 in hydrocephalic babies and 0.0062 +/- 0.001 in control babies, respectively(p < 0.005).

Brain↗

PubMed2000

[Unsuspected hepatic rupture with peritoneal extravasation of contrast media revealed by computed tomography].

Computed tomography (CT) plays a major role as the initial diagnostic tool in adult blunt abdominal trauma. Indications of CT are hemodynamical instability, abdominal defense and high-speed deceleration. We present the case of a 22 year-old man involved in a motor-vehicle accident admitted in our emergency department with headache but without clinical signs of intraabdominal trauma. The abdominal CT was asked because of the high-speed deceleration and because the patient had to come to the CT room for a head CT. The abdominal multislice helical CT performed with contrast bolus injection showed a massive intraperitoneal extravasation from a hepatic laceration and avulsion. The patient died during operation despite immediate management of the abdominal traumatic lesions detected by CT.

Abdominal Injuries↗

PubMedDate not supplied

[The functional assessment of the renal parenchyma and perirenal fatty tissue during electropiezolithotripsy by x-ray computed tomography].

Computed tomography was performed before and after telelithotripsy to evaluate changes in renal parenchyma induced by the procedure in 34 patients with nephroliths. Piezolith-2300 lithotriptor ("Wolf", FRG) was employed. The images showed no serious parenchymal injuries or paranephric hematomas, on the one hand, but density changes in the parenchyma, on the other hand. These were of 3 types: focal reduction in 3, diffuse reduction in 4 and diffuse increase of the density in 2 patients. As shown by comparison with literature data, telelithotripsy on "Piezolith-2300" causes minimal changes in renal parenchyma and perirenal fat. In view of this, the procedure is recommended for wide clinical and outpatient practice.

Adipose Tissue↗

PubMed2005

[Interstitial (lymphogenous) disseminated pulmonary tuberculosis: diagnostic capacities of computed tomography].

Computed tomography (CT) as a priority radiation diagnostic technique for interstitial lung diseases was used to examine 35 patients with disseminated interstitial lymphogenous tuberculosis (ILT). Individuals having ILT amounted to 29% of the total number of the patients with disseminated pulmonary tuberculosis. The major CT markers of ILT are interstitial diffuse bilateral lesion with the reticular or reticulonodular macrostructure. ILT is characterized by its lymphogenous origin with involvement of the superficial and peripheral lymphatic network, by a productive inflammatory reaction showing no tendency to consolidation and cavernization, by none or meager bacterial isolation, by a negative or insignificant tuberculin sensitivity, as well as by difficulties in the identification of a granulomatous component. In terms of the level of damage to the interstitial structures, ILT presented with predominant intralobular interstitial lesion as small reticularity in 16% of the patients, with predominant intralobular interstitial lesion as large reticularity in 59%, and with predominant peribronchovascular interstitial lesion in 25%. The identified CT types of ILT are noteworthy for a chemotherapeutic approach and its results and for the degree of development of interstitial fibrosis.

Adult↗

PubMedDate not supplied

[Diluted barium contrast agent for digestive opacification in abdominal x-ray computed tomography].

Computed tomography is the gold standard technique for abdominal examination with a sliced-imaging modality, because actually US and MRI are not as available for studying hollow viscera. Oral opacification is necessary to analyze bowel loops, and complete iodinated venous injection which is indispensable to examine intra-abdominal organs. Oral administration of a barium diluted contrast agent, is discussed in terms of tolerance, efficacy and administration mode.

Barium Sulfate↗

PubMedDate not supplied

Primary gastric lymphoma: role of computed tomography.

Computed tomography (CT) has been suggested as an alternative to surgery for predicting the stage and resectability of primary gastric lymphoma. It is our policy to perform CT scan on all patients and the decision to explore is based upon CT findings. We reviewed our experience to see if any changes were warranted. 12 patients with primary gastric lymphoma underwent CT scanning. The CT findings were compared with the pathological findings available for 10 patients. CT correctly staged 90 per cent of the patients and it obviated unnecessary exploratory surgery in 42 per cent of the patients. It permitted the planning of non-excisional therapy in 75 per cent of the patients and was useful as an indicator of response to therapy and as a follow up measure.

Endoscopy, Gastrointestinal↗

PubMed1990

[Analysis of mesenteric thickening on computed tomography].

Computed Tomography (CT) provides a noninvasive information in the evaluation of abnormalities of the gastrointestinal tract by direct imaging of the bowel wall and adjacent mesentery. Several prior studies have discussed the variable CT appearances of mesenteric abnormalities, such as lymphoma, metastasis, inflammatory disease and edema. Although mesenteric thickening was mentioned in these studies, no study has provided a detailed analysis of the CT appearance of the thickened mesentery. Two characteristic types of mesenteric thickening were identified in 47 patients. Type I is "Intra-mesenteric thickening", which was noted in 25 patients with vascular obstruction, inflammatory disease and edema. Type II is "Mesenteric surface thickening", which was noted in 22 patients with peritonitis carcinomatosa, peritoneal mesothelioma, tuberculous peritonitis and pseudomyxoma peritoneal. An understanding of these two types of mesenteric disease is important in the identification of mesenteric pathology.

Adult↗

PubMed1990

Osseous temporomandibular joint abnormalities in rheumatic disease. Computed tomography versus hypocycloidal tomography.

Computed tomography (CT) of the temporomandibular joint (TMJ) was compared with hypocycloidal tomography in 30 joints of 15 adults with rheumatic disease. CT included 1.5 mm thick axial scans (at 1.0 mm intervals) with reformatted oblique sagittal and oblique coronal sections. Multisection (at 2.0 mm intervals) tomography included oblique sagittal and occasionally, oblique coronal sections. CT demonstrated bone abnormalities in 21 and tomography in 20 joints, indicating high agreement between the imaging modalities regarding number of abnormal TMJs. Bone structures were, however, better visualized by multiplanar CT due to superior contrast and spatial resolution particularly in the most lateral and medial parts of the joint, indicating superiority of CT for depicting subtle bony TMJ abnormalities in patients with rheumatic disease.

Adolescent↗

PubMed1990

Contrast enhancement of liver parenchyma and biliary tract related to liver function at delayed computed tomography.

Computed tomography (CT) of the liver was performed in 53 patients before, during and 4 to 6 hours after intravenous administration of approximately 60 g of iodine in metrizoate. At delayed CT, contrast medium was observed in the extrabiliary ducts in 20 patients (38%) and in the gallbladder in 28 (68%) of the 41 patients with no previous cholecystectomy. The increase in attenuation of liver parenchyma at delayed CT compared with the non-enhanced baseline CT ranged between 2 and 26 HU (mean 13.9). The material was divided into three groups with regard to liver function: normal, intermediate and pathologic. In the normal group contrast medium was observed in the gallbladder in 81 per cent and in the bile ducts in 57 per cent and the mean increase in attenuation of the liver parenchyma was 14.5 HU. In the pathologic group the same parameters were 40 per cent, 7 per cent and 10.6 HU, respectively. Contrast medium in the gallbladder and biliary ducts improved the information about anatomy. Pathology of the gallbladder and tumour growth along the hepatoduodenal ligament were better demonstrated. Delayed CT is a simple and non-invasive technique that may improve planning of liver surgery.

Biliary Tract↗

PubMedDate not supplied

The spleen in non-Hodgkin lymphoma. Diagnostic value of computed tomography.

Computed tomography of the spleen was correlated with histologic examination or clinical data in 53 selected patients with non-Hodgkin lymphoma. Calculation of the splenic index with CT by multiplying spleen length, width and thickness is a simple and rapid procedure for defining splenic size in vivo. A good correlation was found between size of the spleen, as estimated by splenic index calculation, and the proven or probable histologic state of the spleen.

Adult↗

PubMed1987

Management of orbital blowout fractures: the prognostic significance of computed tomography.

Computed tomography (CT) can be used to aid surgical decision making when the clinical picture is unclear. Patients with blowout fractures and a large amount of orbital expansion and soft tissue herniation have a high risk for developing enophthalmos. Patients with entrapped inferior rectus muscles on CT may continue to have significant diplopia unless they are treated surgically.

Adult↗

PubMedDate not supplied

Superior pericardial recess simulating aortic dissection on computed tomography.

Computed tomography is frequently used in the initial workup of patients with suspected aortic dissection to distinguish dissection involving the ascending aorta from dissection limited to the descending aorta. We reviewed CT of 19 patients who were proven by aortography to have normal ascending aortas. In eight patients the superior extension of the pericardium was visualized and thought to be a potential source of a false-positive diagnosis of type A aortic dissection.

Aortic Dissection↗

PubMed1985

The radiologic approach to malignant tumors of the head and neck, with emphasis on computed tomography.

Computed tomography is the single most effective tool for the investigation and presurgical mapping of the extent of malignant tumors of the upper aerodigestive tract, paranasal sinuses, orbit, skull base, larynx, and neck. Close cooperation between the primary physician and the radiologist is essential for planning an efficient and cost-effective diagnostic plan. The radiologist may also assist the surgeon by obliterating tumor hypervascularity with preoperative fluoroscopically controlled arterial embolization and occlusion.

Adolescent↗

PubMed1985

Diagnosis and localization of intraocular foreign bodies by computed tomography.

Computed Tomography (CT) is the only imaging modality whereby bone and anatomical soft tissue structures are clearly defined. Detection of intraocular foreign bodies (FBs) can be easily obtained by scanning in the axial plane. For the precise localization of FBs, information in two planes is necessary; this is usually achieved by adding a CT study in the coronal plane to the axial plane study. When using a superimposed grid with millimeter calibration on a zoom orbital scan, the accurate location can be calculated. This contribution is of the utmost importance in deciding upon the appropriate approach when surgical removal is indicated.

Adolescent↗