[Paranasal sinusitis: study with conventional and spiral computerized tomography]

This study was aimed at comparing the diagnostic value of conventional computed tomography (CCT) with that of spiral computed tomography (SCT) in sinonasal structures and ostiomeatal complex in thirty patients with inflammatory disease. Ten patients were examined with CCT (3-mm slice thickness, 120 kV, 100 mA, 2-s gantry rotation) and 20 were examined with SCT (3-mm slice thickness, 120 kV, 200 mA, 1-s gantry rotation and computed image reconstruction every 3 mm); table gain was 3 mm (Pitch 1) in 10 patients and 5 mm (Pitch 1.6) in the other 10 patients. With the latter study protocol, diagnostic image quality was the same as with the other two protocols. Moreover, examination time was reduced, with increased patients' comfort; the exposure dose and X-ray tube overload were also reduced, with increased system yield.

[Nodular lesions simulated on an anthropomorphic thoracic phantom. A comparison between analog and digital images of the thorax]

Aim of this work is to evaluate the diagnostic accuracy of different modalities of digital radiology, compared with conventional radiology, in the detection of lung nodules. Forty images of an anthropomorphic chest phantom, on which simulated nodules had been previously set, were analyzed by 6 radiologists with 4 different viewing modalities: a) conventional radiography; b) photostimulable plates digital radiography; c) photostimulable plates digital image on dedicated monitor; d) conventional radiography digitized with Film Laser Digitizer and viewed on Display Workstation. For each image the radiologists had to transfer on a sketch the site of the detected nodules giving an opinion on their detectability (uncertain-presumable-probable-certain presence) with a 1 to 4 score. The statistical analysis of the results was made using modified ROC curves. No statistically significant difference was found between the areas under a) and c) ROC curves (p = 0.262). A statistically significant difference resulted between the areas under a) and d) ROC curves (p < 0.05) and, particularly, between the a) and b) areas (p < 0.001), in favor of a).

[Conventional radiology, digital radiology with photostimulable phosphor, laser digitalization of thoracic radiographic films at the bedside. A comparative study]

The bedside chest images obtained with conventional radiology and with "on line" and "off line" digital modalities were compared to evaluate the respective capabilities in visualizing chest anatomical structures. Seventy patients were submitted to bedside chest examinations with a portable unit; both a conventional film and a digital system (PCR Graphics 1, Philips) with photostimulable phosphor imaging plate were fitted in the radiographic cassette. The former was digitized using an "off line" laser beam unit (FD 2000, Dupont); the latter was subsequently postprocessed by modifying contrast, optical density and spatial frequencies. Thus, 4 different viewing modalities were obtained for each examination: a) conventional radiography; b) standard digital radiography; c) postprocessed digital radiography; d) digitized conventional radiography. Detectability rates of chest anatomical structures were analyzed by 4 independent radiologists on the different images and expressed by a score 1-4. The values were always higher with digital modalities than with the conventional one and the differences were statistically significant (Student's t-test modified by Bonferroni). In particular, the greatest difference was found between c) and a) in retrocardiac lung parenchyma and in skeletal structures, in favour of c). Concerning the comparative adequacy of the various digital modalities, higher detectability rates of chest anatomical structures were obtained with c), but also with b), than with d).

[Digital radiology with photostimulable image plates and conventional radiology in the study of the interstitial pathology of the lung]

To evaluate the diagnostic possibilities of Digital Radiography (DR) and of Conventional Radiography (CR) in the diagnosis of fine chest lesions, 100 patients with AIDS were examined with both techniques. The gold standards were 67Ga scintigraphy and bronchial washing in 100 patients and Computed Tomography (CT) in 50 patients. The data obtained from DR and CR examinations were separately evaluated by 4 readers and subsequently analyzed by ROC curves with Standard Error calculation and by comparing the areas below the characteristic curves with Student's paired t-test (p less than or equal to 0.05). Statistical analysis showed DR and CR to be of equivalent diagnostic value in the study of interstitial lung diseases.

[High resolution computerized tomography in the study of traumatic pathology of the temporal bone]

Thirty-five patients with temporal bone fractures were examined; the fractures were sometimes associated with dislocation of the ossicular chain caused by road fatalities. Computed Tomography (CT) was performed either because of the presence of clinical symptoms associated with trauma of the temporal bone, or because of a hemotympanum discovered during a CT scan of the brain. Thirty-three fractures were detected: 19 longitudinal, 6 transverse, and 8 complex. An incudostapedial dislocation was also detected, together with a displacement of a stapedial prosthesis from the lenticular process of incus, and 3 incus-malleus dislocations associated with fractures. High resolution CT allows the precise definition of the course of the fractures, of the associated dislocation of the ossicular chain, and of facial nerve lesion, thus allowing a more accurate surgical intervention. In the examination of the temporal bone, high resolution CT is preferable to pluridirectional tomography because it is easier and faster to perform. Moreover, high resolution CT helps reduce the radiation dose, and yields higher-quality images with more accurate diagnostic information. High resolution CT also allows the brain and the temporal bone to be studied at the same time.

[Real-time high-resolution echotomography and oral cholecystography in the study of hyperplastic cholecystosis]

A series of 305 patients underwent both cholecystosonography and oral cholecystography. Ultrasounds showed a higher diagnostic accuracy in the diffuse and localized cholesteroloses. Oral cholecystography is still reliable in the diagnosis of adenomyomatosis, especially of the fundus. As present diagnostic and therapeutical indications are nonhomogeneous, early sonographic visualization and follow-up of small cholesterol polyps are valuable for understanding the development of the disease and its clinical and prognostic significance.