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[Value of conventional tomography and computerized tomography in the diagnosis of tumors of the bronchial system].

66 patients with suspected bronchial tumors were examined by conventional tomography and by CT. The results were evaluated separately by two radiologists (A and B). All diagnoses were confirmed by bronchoscopy or surgery. In evaluating individual bronchi, conventional tomography had a sensitivity of 88% (A) or 87% (B) and a specificity of 97% (A) or 95% (B); CT had a sensitivity of 95% (A and B) and a specificity of 99% (A and B). If CT is available, our experience indicates that conventional tomography is no longer indicated.

Adult↗

Comparison of plain radiography, conventional tomography, and computed tomography in detecting intrathoracic lymph node metastases from lung carcinoma.

Forty-two patients with T2 bronchogenic carcinoma were evaluated with plain radiography, conventional 55 degrees oblique hilar and anteroposterior mediastinal tomography, and computed tomography (CT) to compare their accuracy in assessing mediastinal and hilar nodal metastases. Definitive staging was achieved by thoracotomy and histopathological evaluation of resected specimens. All modalities demonstrated about the same accuracy; however, in the 25 patients with hilar and/or mediastinal lymphadenopathy, CT of the mediastinum was more sensitive but not more specific than the other two and conventional tomography was no more accurate than CT for hilar evaluation. Overall, no technique was accurate enough for routine staging; their value may lie in directing biopsy or in treatment planning in patients with inoperable disease.

Carcinoma, Bronchogenic↗

Oblique hilar tomography, computed tomography, and mediastinoscopy for prethoracotomy staging of bronchogenic carcinoma.

Preoperative oblique hilar tomography was used to evaluate hilar lymph nodes in 150 patients with clinically resectable bronchogenic carcinoma. CT was also used in the evaluation of mediastinal lymph nodes in 50 of these patients. Subsequently, all patients underwent mediastinoscopy and/or thoracotomy. Hilar and mediastinal nodes were evaluated for the presence of metastasis, and these findings were then correlated with the radiographic findings of oblique hilar tomography and CT. CT was found to be a reliable method for prethoracotomy staging of bronchogenic carcinoma and for selecting patients for mediastinoscopy. The sensitivity of CT for evaluation of mediastinal nodal metastasis was 83% and the specificity was 90%. Thus patients with negative mediastinal CT need not undergo mediastinoscopy prior to thoracotomy, while mediastinoscopy and biopsy should be done in patients with enlarged mediastinal nodes on CT. Oblique hilar tomography is an accurate method for evaluation of hilar adenopathy and for predicting mediastinal involvement by extrapolation.

Adult↗

Endoscopic ultrasound, positron emission tomography, and computerized tomography for lung cancer.

Staging of patients with lung cancer to determine operability is intended to efficiently limit futile thoracotomies without denying possibly curative surgery. Currently available staging tests are imperfect alone and in combination. Imaged suspected metastases often require tissue confirmation before surgery can be denied. Endoscopic ultrasound (EUS) may help identify inoperable patients by providing tissue proof of inoperability in a single staging test, with similar sensitivity for identifying inoperable patients as other staging tests. Therefore, we compared computed tomography, positron emission tomography (PET), and EUS with fine-needle aspiration under conscious sedation, each test interpreted blinded with respect to the other tests, for identifying inoperable patients in a consecutive cohort of 79 potentially operable patients with suspected or proven lung cancer. An economic analysis was also performed. Thirty-nine patients were found inoperable (a 40th patient's inoperability was missed by all preoperative staging tests). The sensitivity of computerized tomography was 43%. PET and EUS each had similar sensitivities (68 and 63%, respectively) and similar negative predictive values (64 and 68%, respectively), but EUS's superior specificity (100 vs. 72% for PET) and considerably lower expense means it may be preferred to PET early in staging to identify inoperable patients.

Adult↗

Diagnostic and prognostic value of 18-fluorodeoxyglucose positron emission tomography in adrenocortical carcinoma: a prospective comparison with computed tomography.

OBJECTIVE: Patients with adrenocortical cancer are submitted to multiple imaging procedures for diagnosis of recurrence and staging. The aim of this prospective study was to evaluate the diagnostic and prognostic values of fluorodeoxyglucose (FDG) using a combined positron emission tomography and computed tomography (PET/CT) modality, compared with thoracoabdominopelvic computed tomography (TAP-CT). METHODS: Twenty-eight consecutive patients with adrenocortical cancer referred from November 2003 to December 2004 to the Institut Gustave Roussy were included. Mean time between PET/CT and TAP-CT was 16 d. Independent readers analyzed images of each modality. The gold standard was progression on follow-up TAP-CT or pathology. RESULTS: A total of 269 lesions in 57 organs were depicted in 22 patients. The sensitivities for the detection of distinct lesions and the diagnosis of metastatic organs were 90 and 93% for PET/CT and 88 and 82% for TAP-CT, respectively. Twelve percent of the lesions were seen on PET/CT only and 10% on TAP-CT only. Eighteen percent of the metastatic organs were diagnosed with PET/CT only and 7% with TAP-CT only. Thirty-eight percent of the local relapses were seen only with PET/CT. PET/CT depicted three false-positive lesions. Treatment modalities were modified by PET/CT findings in five cases among which one was falsely positive. Tumor size and mitotic rate were significantly associated with FDG uptake. The intensity of FDG uptake (maximum standardized uptake value > 10) and the volume of FDG uptake (>150 ml) were significant prognostic factors for survival. CONCLUSIONS: We show that FDG-PET/CT is complementary to TAP-CT and of special interest in the diagnosis of local relapses.

Adrenal Cortex Neoplasms↗

The role of computed tomography and coronal plane tomography in radiotherapy for laryngeal cancers.

The results of a study undertaken prospectively in 1983 and 1984 to assess the value of computed tomography (CT) and conventional tomography in the planning of radiotherapy for laryngeal cancer are presented. Of 32 cases treated in 1983, 23 had both CT scans and coronal plane tomography prior to radiotherapy. At the end of 1983 these radiographs were reviewed and an assessment made of their value in treatment planning. As a result of this review it was decided that cancers of the larynx confined to the vocal cords should routinely have conventional coronal plane tomograms rather than CT scans. All other cases were to have CT scans and not tomograms. The results of following this policy in 1984 confirm that it is effective. There was no detriment to patients with early vocal cord cancers in performing coronal plane tomograms rather than CT scans. The survival at 24 months of both cohorts was 93%. In the more invasive cancers of the larynx, greater information about the extent of the disease was obtained using CT scans, and improved treatment plans resulted. When compared with a historical group, there appears to be an advantage for local control, 27.3% of the study group suffering local recurrence as opposed to 53.6% of the historical group.

Follow-Up Studies↗

Absorbed doses from computed tomography for dental implant surgery: comparison with conventional tomography.

Tomography is often needed prior to implant surgery to evaluate jaw bone dimensions. Computed tomography (CT) is advocated as an alternative. The purpose of this study was to measure the absorbed doses to radiosensitive organ in the head and neck region when CT is used. Measurements were made with extruded LiF thermoluminescent dosemeters within and on an anthropomorphic phantom examined with a Philips Tomoscan LX CT scanner. Axial scanning was performed for the maxilla and both frontal, perpendicular to the alveolus, and axial for the mandible. The highest absorbed doses were at the skin surface, 38 mGy with maxillary scans, and from axial and frontal scans of the mandible 35 mGy and 37 Gy, respectively. The parotid dose was 31 mGy from maxillary scans and in the mandible the submandibular gland dose was 27 mGy with axial scanning and 16 mGy with frontal. The eye lens received its highest dose (5.5 mGy) from frontal scans of the mandible. Although outside the scanning plane the pituitary and the thyroid glands received comparatively high absorbed doses of 0.6-4.0 mGy. All organ doses measured were considerably higher than those reported for conventional tomography.

Absorption↗

Computerized tomography, magnetic resonance imaging, and positron emission tomography in the study of brain trauma. Preliminary observations.

Results of computerized tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), xenon-133 measurement of cerebral blood flow (CBF), and neuropsychological assessments are described in three head-injured patients. The patients were selected because they presented with intracranial hemorrhage diagnosed by CT. Two of the patients were studied acutely and again approximately 6 months later. In the acute stage, MRI was superior to CT in identifying the precise location and extent of intracranial hemorrhage and associated edema. Small subdural hematomas diagnosed on MRI were missed with CT scanning. The extent of apparent encephalomalacia in the chronic stages of injury was also better defined with MRI. Positron emission tomography showed disturbances of glucose metabolism that extended beyond the structural abnormalities demonstrated by MRI and CT; anterior temporal lobe dysfunction was particularly evident in all three patients. Regional CBF studies failed to detect a number of the abnormalities seen on MRI and CT, and even ignored the metabolic dysfunction evident on PET that should have been accompanied by changes in regional CBF. The neuropsychological studies localized frontal lesions, but did not reveal abnormalities attributable to the structural lesions and the reduced metabolism in the anterior temporal lobes.

Adult↗

Comparison between positron emission tomography and computed tomography in the use of the assessment of esophageal carcinoma.

BACKGROUND: The role and potential value of positron emission tomography (PET) scanning in certain tumors has been widely investigated in recent years. The authors retrospectively assessed the performance of 18-F-fluorodeoxyglucose (FDG)-PET in the assessment of esophageal squamous cell carcinoma (SCC). METHODS: The results using PET were compared with those using computed tomography (CT), and these were correlated with the pathologic findings. The authors studied 32 patients with thoracic esophageal SCC who had undergone radical esophagectomy. RESULTS: Uptake of FDG in the primary tumor was found in 25 of the 32 (78.1%) cases. Comparison of the FDG uptake and the clinicopathologic findings showed that there was a significant association between the FDG uptake and each of the depth of tumor invasion (P < 0.05), occurrence of lymph node metastasis (P < 0.01), and lymphatic invasion (P < 0.01). The survival rate in cases with high FDG uptake (standardized uptake value [SUV], >3) was significantly lower than that in cases with low FDG uptake (SUV, < 3; P < 0.05). In the evaluation of lymph node staging by the detection of lymph node metastasis, FDG-PET showed 77.8% sensitivity, 92.9% specificity, and 84.4% accuracy, and CT scanning showed 61.1% sensitivity, 71.4% specificity, and 65.6% accuracy. Positron emission tomography scanning showed a high degree of accuracy in the neck, upper thoracic, and abdominal regions. However, in the mid- and lower thoracic regions, the sensitivity was very low. The smallest lymph node metastasis that was detected by FDG-PET imaging was 6 mm. The average size of lymph node metastasis that was undetected by FDG-PET scanning was 7.3 mm (range, 1-17 mm). CONCLUSIONS: In conclusion, FDG-PET may be used as a noninvasive diagnostic technique in assessing the aggressiveness of the tumor and the prognosis in patients with esophageal SCC. During the preoperative diagnostic procedures, the sensitivity, specificity, and accuracy of lymph node staging is higher with FDG-PET than with CT imaging. In view of the high specificity of FDG-PET, it also gives useful information to guide the choice of treatment of esophageal carcinoma.

Adult↗

[Evaluation of the effectiveness of preoperative polychemotherapy of nephroblastomas in children by angiography, ultrasonic tomography and computed tomography].

The results of preoperative polychemotherapy of nephroblastoma in 14 children are presented. Ultrasonic tomography, computed tomography and angiography were performed in all the patients before and after medication. The findings on the efficacy of polychemotherapy were assessed on the basis of surgical evidence and, in particular, resected material examination. A high diagnostic value of all the methods was demonstrated and criteria of the effectiveness of preoperative polychemotherapy as evaluated by application of ultrasonic and computed tomography and angiography were worked out. Optimal terms of carrying out diagnostic procedures in patients with nephroblastoma during preoperative treatment are suggested.

Angiography↗

Otosclerosis: comparison of complex-motion tomography and computed tomography.

A prospective computed tomographic and complex-motion tomographic evaluation was performed in 18 suspected or proven cases of otosclerosis. Although there was good agreement between both methods, there was no greater diagnostic accuracy with computed tomography. However, computed tomography demonstrated the changes better than complex-motion tomography.

Evaluation Studies as Topic↗

[Experimental dosimetric comparison between single tomography and multiple simultaneous tomography with Synchroplan in clinical practice].

Reference is made to a dosimetric comparison between single tomography and simultaneous multiple tomography with Synchroplan in 10 patients subjected to nefroangiotomography. Data from several thermoluminescence dosimeters placed on different parts of the body were used in a careful statistical analysis that showed the absence of significant differences in absorbed dose in function of constitutional habitus. It was also found that the dose absorbed for 6 tomograms of the renal cavities in single tomography was about 4 times higher than with the Synchroplan (using a previously experimented set of high-sensitivity intensifying screens), which provides 6 tomograms in the same dynamic phase at different levels for the same exposure.

Body Constitution↗

Evaluation of the pulmonary hilum: comparison of conventional radiography, 55 degrees posterior oblique tomography, and dynamic computed tomography.

In 84 patients with suspected intrathoracic neoplasms we compared the accuracy of conventional radiography, 55 degrees posterior oblique tomography, and contrast-enhanced dynamic incremental computed tomography (CT) in evaluation of the pulmonary hilum. We found dynamic incremental CT to be better than either conventional radiography or oblique tomography in hilar evaluation. In addition, significant information was detected in extrahilar and extramediastinal locations by CT in 21% of patients. This study, unlike earlier reports, indicates a role for CT in hilar evaluation.

Adenocarcinoma↗

Transaxial tomography: an alternative to computerized tomography in pediatric orthopedic problems.

Because of the information it provides, computerized tomography has gained wide acceptance. However, the radiation delivered is considerable, and the gonads cannot be shielded effectively. Transaxial tomography also produces a cross-sectional image. While the image has less resolution, it is obtained at a fraction of the exposure. The use of transaxial tomography in several clinical situations is outlined here.

Bone Diseases↗

Brain sonography, computed tomography, and single-photon emission computed tomography in term neonates with perinatal asphyxia.

The clinical diagnosis of hypoxic-ischemic brain injury in neonates can be supported by radiologic studies including cranial sonography, computed tomography (CT), single-photon emission computed tomography (SPECT), magnetic resonance imaging, and positron emission tomography. The role of cranial sonography, CT, and SPECT in term neonates with perinatal asphyxia is reviewed in this article.

Adolescent↗

Paradoxical emboli: demonstration using helical computed tomography of the pulmonary artery associated with abdominal computed tomography.

We report the case of a 60-year-old woman with a recent history of a cerebrovascular accident. Because of clinical suspicion of pulmonary embolism and negative Doppler ultrasound findings of the lower limbs, spiral computed tomography of the pulmonary artery was performed and demonstrated pulmonary emboli. We emphasize the role of computed tomography of the abdomen, performed 3 min after the thoracic acquisition, which showed an unsuspected thrombus within the abdominal aorta and the left renal artery with infarction of the left kidney. Paradoxical embolism was highly suspected on computed tomography data and confirmed by echocardiography which demonstrated a patent foramen ovale.

Aorta, Abdominal↗

Gadolinium-enhanced computed tomography angiography in multi-detector row computed tomography: initial observations.

RATIONALE AND OBJECTIVES: The feasibility of using gadolinium contrast medium for computed tomography angiography (CTA) in multi-detector row computed tomography and the effect of contrast medium dilution was investigated. MATERIALS AND METHODS: Three pigs were each scanned in multiple sessions with injections of non-dilute and dilute contrast medium at a dose of 0.3 mmol/kg body weight. Non-spiral dynamic scanning at a fixed mid-abdominal aortic level and thoracoabdominal CTA were performed. RESULTS: The magnitude of peak aortic enhancement was not significantly different between dilute and non-dilute contrast medium injections (P = .88), but the former showed earlier enhancement (mean of 2.3 seconds sooner, P < .01) than the latter. CT angiography with gadolinium contrast medium showed much lower enhancement than iodine contrast medium, but small vessels were readily identifiable. CONCLUSION: Gadolinium contrast medium combined with multi-detector row computed tomography may provide clinically useful CTA. Dilution of contrast medium shortens the enhancement time but has little effect on the magnitude.

Angiography↗

[A comparison of xero-tomography of the lung hilum with conventional tomography (author's transl)].

Because of its particular photoelectric properties, xero-tomography is particularly suited for the investigation of abnormalities in the hilar regions. It is superior to conventional tomography because of the improved edge contrast, which emphasises details of relatively non-opaque structures, and because of its high exposure latitude. This justifies its use despite the higher radiation dose that is necessary. The demonstration of relatively dense and of more transradient tissues on the same picture by xero-tomography, and the ability to read it by ordinary light, makes it less tiring to interpret than the translucencies of conventional radiographs.

Adult↗