[A comparison between traditional mammography and digital with storage phosphors]. / Confronto tra mammografia tradizionale e digitale con fosfori a memoria.

Conventional and digital mammographic images obtained with storage phosphors were compared. The digital images were acquired with high-resolution 3rd-generation (HR III) screens and specifically adapted algorithms. The experience was made both on a phantom and in vivo. The phantom study was carried out by comparing conventional with digital radiographs acquired with: a) same kV (28) and same mAs; b) same kV (24) and same mAs; c) 28 kV with 30% mAs reduction, in digital images only. The results obtained upon counting the amount of recognizable details per image demonstrated slight loss of information in digital radiographs only when mAs was reduced by 30%. Two hundred patients were studied; they were divided into four groups according to the type of breast (medium inherent contrast or solid breast) and to exposure factors. After conventional mammography, an additional digital radiograph was performed using one of the three techniques previously employed on the phantom. Separately, 10 ductogalactographies and 10 magnification radiographs of microcalcifications were compared; the same exposure factors were used in these images too. The radiographs were viewed by three expert mammographic radiologists; contrast quality and spatial resolution were investigated and a score was given to each image on a 3-grade scale (insufficient, sufficient, good). The comparison of the mean values obtained showed higher contrast and better enhancement of nodular lesions on digital images, on which, however, the depiction of microcalcifications was worse than on conventional radiographs, especially with lower radiation doses, even though the number of detected microcalcifications was the same.

[Radiologic study of the thorax using the digital method (FCR 101). Evaluation of various parameters as related to exposure]. / Studio radiologico del torace con metodica digitale (FCR 101). Valutazione di alcuni parametri in relazione alla esposizione.

A computed radiography system with solid state detectors (FCR 101) was employed to evaluate the quality of digital images, with optimal and progressively lowered doses, in the study of the chest. Routine chest radiographs of in patients with no pathologic conditions of the chest were studied. The patients were divided into 3 groups: each patient in group A underwent two radiographs, one at 100% and the other at 50% exposure; patients in group B were imaged with 100% and 25% doses, and those in group C received 50% and 25% exposure. Several parameters were employed for image evaluation, and a value was given to each of them (1 = good, 2 = sufficient, 3 = insufficient). Upon comparison of the average values obtained, we observed that the digital technique allowed a most accurate and well-defined representation of the examined parameters at 100% exposure dose and that a 50% reduction did not decrease the informative content in the least. A 25% reduction, however, determined a high degree of background noise and a subsequent, though slight, loss of information.

[Double-contrast enema. Study of the mucosal pattern and the organ profile with conventional and digital methods]. / Clisma a doppio contrasto. Studio del disegno mucoso e del profilo d'organo con le metodiche tradizionale e digitale.

A solid state digital system (FCR 101) was employed in our comparative evaluation of the image quality of conventional versus digital techniques in the study of colon by means of double-contrast enema. Sixty patients were examined with a single AP view, using digital radiography with 100% radiation dose and progressive 50% and 75% reductions; the radiographs thus obtained were then compared with the corresponding conventional ones. The examined parameters were organ profile and mucosal pattern. Each digital and conventional radiograph was evaluated by 2 independent radiologists and a value was given to each parameter i.e., 1 = good, 2 = sufficient, 3 = insufficient. Upon comparison of the average values obtained for digital and conventional radiographs in optimal conditions and with a dose reduced by 50%, the digital technique was seen to give a more detailed and accurate representation of both low-contrast mucosal pattern and of organ profile. With the dose reduced by 75%, a slight increase was observed in background noise which caused a slight loss in image definition, but this did not reduce image readability with respect to conventional radiographs. To conclude, the digital method with a 50% exposure reduction is to be preferred in the examination of the colon, especially in pediatric radiology; furthermore, since this technique allows better detailing at lower contrast, it is to be preferred in the study of the pathologic conditions affecting mainly/only the mucosal pattern--e.g., cancer, ulcerative colitis, Crohn's disease, and so on. An exposure dose reduced by 75% may be used for following lesions previously diagnosed and when a less detailed depiction of the mucosal pattern is enough.