Imaging after radiofrequency ablation of renal tumors.

The number of percutaneous radiofrequency ablation procedures performed for renal tumors is progressively increasing worldwide. Periodic imaging follow-up has the double role to guarantee the treatment efficacy over time and to early detect any possible complication. Tumor size reductions, as well as the appearance of the characteristic 'halo sign', are normal findings that represent good ablative outcomes. However the most reliable factor of ablation efficacy remains the total absence of contrast enhancing zones within the ablated area. The aim of this article is to illustrate the typical aspect of an effective radiofrequency ablation treatment, which are the imaging findings that may suggest the presence of residual tumoral tissue and which are the main early and late procedural complications.

MRI in acute ligamentous injuries of the ankle.

Ankle sprains are the most common lower limb injuries and affect more frequently young athletes; imaging is needed for an accurate diagnosis of such traumatic injuries. The purpose of this review is to analyse the magnetic resonance (MR) findings of both normal and pathological ankle's ligaments; indeed, MRI is the gold standard for the diagnosis of acute traumatic injuries and is useful for differentiation of the causes of ankle instability as well as for pre-operative planning.

Use of DWI in identification of small solid pancreatic focalities (≤ 2 cm).

Incidental finding of pancreatic focalities has increased thanks to a larger use of radiological examinations (Ultrasound, CT). The differential diagnosis between focal inflammatory and heteroplastic disease is frequently complicated by the wide spectrum of lesions and by the aspecificity of clinical and medical history, as well as of imaging findings. MRI is the second level choice of examination thanks to its higher intrinsic contrast resolution and parametric capability (1); furthermore, the use of Diffusion Weighted Imaging (DWI) sequences provides additional diagnostic informations.

Defecography: a still needful exam for evaluation of pelvic floor diseases.

The aim of this discussion is to describe what is a defecography, how we have to perform it, what can we see and to present the main physio-pathological illnesses of pelvic floor and anorectal region that can be studied with this method and its advantages over other screening techniques. Defecography is a contrastographic radiological examination that highlights structural and functional pelvic floor diseases. Upon preliminary ileum-colic opacification giving to patient radiopaque contrast, are first acquired static images (at rest, in maximum voluntary contraction of the pelvic muscles, while straining) and secondarily dynamic sequences (during evacuation), allowing a complete evaluation of the functionality of the anorectal region and the pelvic floor. Defecography is an easy procedure to perform widely available, and economic, carried out in conditions where the patient experiences symptoms, the most realistic possible. It can be still considered reliable technology and first choice in many patients in whom the clinic alone is not sufficient and it is not possible or necessary to perform a study with MRI.