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M L Storto

Publications and source records attributed to M L Storto.

34 records · Page 2Linked to original sources
PubMed1994

Spiral CT of the mediastinum: optimization of contrast medium use.

Spiral computed tomography (CT) allows very satisfactory temporal resolution for the detection and analysis of changes in contrast medium density, so that volumes of contrast material smaller than those recommended for conventional CT can be used. The present double-blind, parallel group study was designed to compare image quality and diagnostic efficacy obtained with two different iodine strengths (200 and 300 mgI/ml) and two different flow rates (2 and 3 ml/s) of a fixed volume (70 ml) of iomeprol in adult consenting patients requiring spiral CT of the mediastinum. Imaging was performed during suspended respiration and, a 15-s delay to scan. Spiral CT was initiated 1 cm above the aortic arch and continued inferiorly for 24 cm in all patients. Two independent readers blindly graded image quality, opacification of the superior vena cava, thoracic aorta and pulmonary arteries, and overall diagnostic quality of the CT examination. CT density measurements were performed over the level of the aortic arch, left and right pulmonary arteries, left atrium, and descending aorta. Opacification of the mediastinal vessels was better in the patients injected at 3 ml/s flow rate and was independent of the iodine strength used, except in the case of the thoracic aorta, which was better opacified by injecting iomeprol 300 mgI/ml at 3 ml/s. The highest diagnostic efficacy of the spiral CT examination was obtained with iomeprol 300 mgI/ml at 3 ml/s infusion rate, which seems to represent the administration scheme of choice.

Adult↗
PubMed1993

[Volumetric computerized tomography (spiral CT). Technical principles and possible applications in the thorax].

Spiral volumetric CT is a new volume scanning technique allowing the one-acquisition imaging of an anatomical volume, by advancing the patient through a continuously rotating X-ray tube. As a result, the X-ray tube moves in spirals around the patient and this is the reason why this new technique is called Spiral CT. At the end of the acquisition, planar images are reconstructed by means of a dedicated image reconstruction algorithm with a linear interpolation between two contiguous spiral segments. Spiral CT offers many advantages, all resulting from the possibility of evaluating anatomical volumes in a short time: the organs which are subject to respiratory motion can be studied in a single breath-hold scan, the quality of secondary reconstructions (2/3 dimensional) is improved, the use of contrast media is optimal and finally motion artifacts are reduced. The authors report their early experience with spiral CT in the chest. Spiral CT is more reliable than conventional CT in the evaluation of pulmonary nodules, which can be easily identified with no risk of missing small lesions, and of the pulmonary apex and of the diaphragm. Moreover, contrast media can be used at a lower dosage than usually recommended with conventional CT.

Adolescent↗
PubMed1992

[Neoplastic involvement of pulmonary fissures. Diagnostic possibility of high resolution x-ray computed tomography].

Acknowledging fissure invasion by pulmonary tumors located in contact with or in the vicinity of a fissure is an important piece of information for the therapeutic choice, especially in patients whose functional respiratory impairments are a contraindication of pneumonectomy. Fifteen patients with pulmonary neoplasms adjacent to a fissure were studied with standard computed tomography (10 mm sections), completed by high-resolution CT. The findings of the CT studies were compared with those operative reports. On surgery, the oblique fissure was infiltrated in 12 patients, unharmed in 2 others, while the horizontal fissure was infiltrated in 3 patients. Standard CT allowed diagnosing the involvement of the oblique fissure in 4 patients. Thin sections with high-resolution reconstruction algorithms allowed detecting the involvement of the oblique fissure in 13 cases, including one false-positive result. On thin sections, the fissures appear as well-delineated, dense lines. This allows an accurate study of the relationships between the tumor and the fissure, thus increasing the sensitivity of CT for the detection of tumoral extension across the fissures. The orientation of the horizontal fissure, which is almost parallel to the plane of section, makes the study of its relationships with an adjacent mass difficult, even in high-resolution CT.

Humans↗
PubMed1992

[Bronchogenic carcinoma staging: comparison of magnetic resonance/computerized tomography].

The staging of bronchogenic carcinoma is an important factor to select the appropriate treatment. Indeed, the definition of locoregional spread and of hilar and mediastinal node involvement is essential for both correct preoperative assessment and prognostic evaluation of bronchogenic carcinoma. CT and MR imaging are the methods of choice in the evaluation of T and N, even though other techniques--e.g., US and nuclear medicine--can also provide valuable diagnostic information. The authors examined 50 patients with primary bronchogenic carcinoma by means of plain radiographs, CT and MR of the chest. MR and CT findings were compared with surgical results on the basis of TNM classification. In the evaluation of T, sensitivity and specificity were 66% and 88.6%, respectively, for CT and 76% and 92% for MR imaging. No statistically significant differences were found between the two imaging methods (p = 0.19). In the evaluation of N, sensitivity and specificity were 56% and 78%, respectively, for CT and 76% and 88% for MR imaging. A statistically significant difference was found between MR and CT accuracy rates (p = 0.934). CT and MR results were in disagreement especially in the evaluation of hilar lymph nodes. To date, MR imaging cannot be considered a substitute for or a routine adjunct to CT in the staging of bronchogenic carcinoma due to its poor spatial resolution, to the presence of artifacts (especially with high-intensity fields), its cost and limited availability. However, in the evaluation of specific anatomical regions--e.g., the pulmonary apex and the peridiaphragmatic region--MR can provide more diagnostic information than CT thanks to its multiplanarity and better contrast resolution.

Humans↗
PubMed1991

[Neoplastic involvement of pulmonary fissures. Usefulness of high resolution CT].

In order to plan an adequate treatment, it is very important to recognize the transfissural spread of lung cancer near a pleural fissure, especially in the patients who cannot bear pneumonectomy because of impaired pulmonary function. Fifteen patients with lung cancer near a fissure were examined by means of conventional CT (10 mm-thick slices) followed by high-resolution CT (HRCT). The results obtained with both techniques were compared with surgical findings. At surgery, major fissure involvement was seen in 12 cases, minor fissure was involved in 3, and 2 patients were normal. In 4 cases fissural involvement was correctly demonstrated by conventional CT scans. Neoplastic involvement of the major fissure was identified in 13 cases by HRCT scans, with only 1 false positive. Pleural fissures appear as thin and sharp lines on HRCT scans. Thus, the relationship of lung cancers to fissures is better identified and the accuracy of the method in defining neoplastic spread is higher. However, the relationship of a neoplastic mass to the minor fissure is difficult to evaluate, because the fissure is roughly parallel to the scanning plane.

Humans↗
PubMed1990

[Opaque enema and radiography of defecation in the pre- and postoperative morpho-functional evaluation of rectal neoplasms].

From November 1989 to April 1990, 16 patients with rectal cancer were examined preoperatively by means of double contrast barium enema and defecography. Double contrast barium enema was used to identify the cancer: based on the distance of cancer from anal rima, the patients were divided into 3 groups: 1) less than 6 cm; 2) 6-11 cm; 3) more than 11 cm. In all patients defecography was performed at the end of barium enema to evaluate rectal wall mobility. Thus, the morphological information yielded by barium enema could be integrated with the dynamic data from defecography. The evaluation was thus possible of both longitudinal and, indirectly, transverse tumor spread. All the patients underwent surgery and radiological findings were compared with surgical ones. In those patients in whom defecography had shown rigidity of the rectal walls, extraparietal tumor spread was observed during surgical resection. Seven patients underwent anterior resection, and were subsequently examined by the same combination of barium enema and defecography. The combined use of the two methods was useful to evaluate the anastomosis and to show possible dynamic changes after surgery.

Barium Sulfate↗
PubMedDate not supplied

[Bedside thoracic radiography: a comparison between 3 different types of grid].

Bedside chest radiography accounts for an increasingly large portion of all chest X-ray examinations. Nevertheless, image quality is often poor mainly because of scattered radiations which decrease image contrast. Moreover, usually no grid is employed because of difficult beam alignment. This work was aimed at comparing different radiologic grids for bedside chest radiography. Fifty patients submitted to two bedside chest radiographs in 24 hours were studied. All the patients underwent the first exam with a Kodak InSight cassette with a newly-designed (columnar type) grid inside, while the second exam was performed with a conventional 8:1 focused lead-strip grid (Gilardoni) in 25 patients and with a 6:1 focused lead-strip grid (Gilardoni) in the extant 25 patients. Both grids were assembled in a Kodak InSight radiographic cassette. Three independent radiologists evaluated film quality, focusing on the depiction of some anatomical structures--e.g., the tracheobronchial tree, the retrocardiac lung, and devices. Seventy-five examinations were obtained for each grid and for each evaluated structure and graded as "good", "acceptable" and "poor". In the 6:1 vs columnar grid test, the highest rate of "good" and "acceptable"--i.e., diagnostic--findings was observed with the columnar grid in evaluating pulmonary vessels (71/75); the highest rate of "poor" findings was obtained with the same grid in evaluating tracheal bifurcation (43/75). In the 8:1 vs columnar grid test, the highest rate of diagnostic findings was shown by the conventional grid in evaluating retrocardiac lung parenchyma and by the columnar grid for pulmonary vessels (69/75); the highest rate of "poor" findings was obtained with the columnar grid in evaluating tracheal bifurcation (40/75). The statistical analysis of the results (Wilcoxon test) was made to compare the two conventional grids with the new columnar one. Statistically significant differences were observed between the 8:1 grid and the columnar grid to evaluate the bronchial tree. No differences were observed between the 8:1 grid and the columnar grid. Furthermore, to determine the effects of different degrees of grid decentering on image quality, a series of exposures was made using a lung-chest phantom. The grids, both the lead-stripe and the columnar one, were comparable. The higher-ratio grid proved better in evaluating tiny details. The columnar grid exhibited better tolerance to X-ray beam and to grid decentering.

Equipment Design↗
PubMedDate not supplied

Pulmonary embolism: the role of computed tomography and magnetic resonance imaging.

The technological progress in Computed Tomography (CT) (spiral and electron beam) and Magnetic Resonance Imaging (MRI fast sequences) has stimulated their interest in the diagnosis of acute and chronic pulmonary embolism (PE). They are noninvasive procedures able to identify thrombi up to the level of segmental pulmonary branches. This result, albeit not ideal, is significant, in view of the lower clinical relevance of peripheral emboli as compared to more central locations, especially in the absence of peripheral venous thrombosis. Spiral CT allows satisfactory assessment of pulmonary branches with high sensitivity (65-100%), specificity (89-96%), positive predictive value (95%) and negative predictive value (80-100%) in the diagnosis of PE. MRI with spin-echo sequences has also a satisfactory sensitivity (75-90%), specificity (up to 100%), positive predictive value (86%) and negative predictive value (85%). Recently, MR angiography was shown to be able to depict smaller pulmonary branches (6th and 7th generation), even if its efficacy in the identification of emboli has not been demonstrated as yet. CT and MRI are bound to play an increasingly relevant role in the diagnosis of PE.

Humans↗