[Echography and magnetic resonance of the penis. I. Its anatomy]. / Ecografia e risonanza magnetica del pene. Parte I.--Anatomia.

The use of such new diagnostic imaging methods as ultrasonography (US) and Magnetic Resonance Imaging (MRI) has given radiology an increasingly important role in the study of penis abnormalities. The normal anatomy of the penis was investigated with US with real-time units, high-frequency linear probes, and with an 0.5-T MR unit. The two methods are definitely better than conventional radiologic techniques because they allow the direct and detailed demonstration of all anatomical structures. Both the normal and the abnormal anatomy are better depicted when the exam is performed after pharmacologically induced erection. The normal US and MR features of the different anatomical structures must be known to diagnose penis conditions. US exhibited better spatial resolution than MRI and demonstrated very small structures which may be missed at MRI because of gap interslices. On the other hand, MRI exhibited better contrast resolution, especially on T2-weighted sequences. Thus, the two imaging methods must be considered as complementary, even though US is suggested as the method of choice because of its cost-effectiveness and widespread availability.

[The use of a questionnaire to test the reliability of protocols for the indication of radiologic tests in emergencies]. / Impiego di un questionario a verifica dell'affidabilità dei protocolli di indicazione agli esami radiologici nelle urgenze.

The authors developed a series of protocols for selecting patients who need emergency radiography, based on clinical criteria that maximize the yield of abnormal radiographs. In order to test safety and reliability of the protocols and to define the reasons for requesting emergency radiographs, a prospective analysis was carried out, by means of a questionnaire, on 1000 consecutive patients referred to our Accident and Emergency Department for radiography. Seven hundred and twenty-nine patients were considered as negative according to protocol criteria: none of them was found positive on X-ray examination. Of them, 639 exams were requested for medico-legal reasons and 90 for patient reassuring. Of 271 patients considered as true positive or probably positive according to the screening criteria, all the true positive cases were such also on X-ray examinations, whereas, among the probably positives, only 31 were confirmed as positive on radiological studies. Our results demonstrate the efficacy of the suggested protocols: had these referral criteria been used for the patients in our study, only 271 examinations would have been performed with no radiographic abnormalities missed. In addition, this grid included 94 cases evaluated as "probably" positive which were subsequently found negative at X-rays, which makes a further safety margin. Our analysis also shows the low therapeutic value of emergency radiographs in both nasal bone injury and post-traumatic oblique rib views. Therefore we suggest selecting patients who need X-rays based on the clinical criteria shown in our protocols: this could result in economic saving and decreased radiation exposure, with no risks of clinical underestimation of the pattern.