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M Pistolesi

Publications and source records attributed to M Pistolesi.

64 records · Page 4Linked to original sources
PubMed1978

Chest tomography by gamma camera and external gamma source: concise communication.

To obtain tomographic images of the chest, we used a large-field gamma camera to detect the 90 degrees scattered radiations (180 keV) from a linear source of Hg-203 (279 keV). The primary beam traveling across the chest is scattered according to the relative density of tissues. Chest sections can be visualized at different depths on frontal and sagittal planes. The resolution of the technic is that of the gamma camera.

Gamma Rays↗
PubMedDate not supplied

[High resolution and spirometric synchronization computerized tomography in chronic obstructive bronchopneumopathy].

PURPOSE: To assess the feasibility of spirometrically gated HRCT in patients with chronic obstructive pulmonary disease and to correlate the density measures with the results of pulmonary function tests. MATERIAL AND METHODS: Pulmonary function tests and spirometrically gated HRCT were performed, on the same day, in 20 patients with chronic obstructive pulmonary disease. Spirometrically gated HRCT scans at 90 and 10% of the patient's vital capacity were acquired, at three anatomical levels (carena, carena plus 5 cm, carena minus 5 cm). In each section, lung parenchyma was isolated from the other thoracic structures and from the main bronchi and a densitometric evaluation was applied to the regions of interest. A histogram showing the distribution of the pixel frequencies versus lung densities, the mean CT number and the pixel index at -910 HU (for scans acquired at 10% of the patient's vital capacity) and at -950 HU (for scans obtained at 90% of the patient's vital capacity) were obtained. Average acquisition time for the spirometrically gated HRCt was 15-20 minutes, average data processing time was 20 minutes. RESULTS: The mean CT number and the pixel index at -910 HU obtained at 10% of the patient's vital capacity correlated with the Tiffeneau index (r = 0.85; R = 0.78 respectively). The pixel index at -910 HU correlated also with the ratio of residual volume to total lung capacity (r = 0.65). The mean CT number and the pixel index obtained at 90% of the vital capacity correlated with the lung diffusion of carbon monoxide (r = 0.64 and r = 0.79 respectively). CONCLUSIONS: In our study, we found good correlation between the densitometric values obtained with spirometrically gated HRCT and the respiratory function tests routinely employed to assess the presence and the gravity of obstructive pulmonary disease. A good reproducibility of the data is guaranteed by the spirometical gating which enables standardization of the lung acquisition volume, and by the semiautomatic contour tracing program combined with an automated densitometric evaluation. The main disadvantages of the technique are the relatively long acquisition and evaluation times. Spirometrically gated HRCT densitometry is a promising tool for longitudinal studies of diffuse lung disease (pulmonary emphysema and fibrosis).

Adult↗
PubMedDate not supplied

SPECT perfusion imaging with 123I-HIPDM in a patient with pulmonary embolism.

The use of 123I-N,N,N'trimethyl-N'-2-hydroxy-3-methyl-5-iodobenzyl-1,3-propanediami ne (123I-HIPDM) as a lung perfusion tracer in a patient with pulmonary embolism is shown. 123I-HIPDM is compared with 99mTc-labeled human albumin microspheres (HAM) using both planar and tomographic (SPECT) imaging. Pulmonary segmental defects are shown by 123I-HIPDM as well as by HAM, with a slightly better definition of perfused areas. Tomograms better show segmental shape of perfusion defects. 123I-HIPDM may be proposed as lung perfusion tracer for both clinical and experimental purposes.

Humans↗
PubMedDate not supplied

[Quantification of pulmonary emphysema with computerized tomography. Comparison with various methods].

Computed Tomography (CT) has been proved to be the most accurate imaging modality to diagnose emphysema in vivo. Our study was aimed at comparing different CT methods for pulmonary emphysema quantification in patients with severe chronic obstructive pulmonary disease (COPD). Forty-six consecutive inpatients affected with COPD underwent high resolution CT (HRCT). Three scans were acquired at 3 preselected anatomic levels at both full inspiration and expiration. Three different observers were asked to subjectively evaluate, under blind conditions, the extent alone and both the severity and the extent of emphysema on the 6 scans. HRCT findings were also analyzed quantitatively by measuring the mean CT number in Hounsfield Units (HU) and the % of lung area with CT numbers < -900 HU (pixel index). Quantitative CT data were compared with reference values obtained in 7 normal nonsmokers. The CT visual score of emphysema exhibited medium-high interobserver reproducibility with correlation coefficients ranging from 0.80 to 0.96 and a good correlation with pulmonary function tests, particularly relative to the assessment of the extent of emphysema alone as expressed by one observer. CT quantification demonstrated an excellent correlation with functional indices of expiratory airflow, lung volumes and diffusion coefficients (p < 0.001). The expiratory measurements were better than the inspiratory ones while the analysis of both CT number and pixel index gave comparable results. Only the CT expiratory quantitative data allowed to differentiate the patients affected with COPD from the controls. In conclusion, the severity of emphysema as expressed by CT correctly reflects the functional impairment of patients with severe COPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗