Desmoplastic fibroma of the mandible.

We report the imaging findings of a desmoplastic fibroma (DF) of the mandible in a 3 years old girl. DF of bone is a rare, no-metastasizing but locally aggressive tumor. Hypercellularity, nuclear pleomorphism, mitotic activity, and traces of odontogenic epithelium and bony tissue are absent. US exam showed a highly vascular and well delimited mass, with no necrotic/hemorrhagic areas. It appeared as a well-defined osteolytic region in RX and a multiloculated, hypodense mass, with no periosteal reaction signs, in CT scans. MRI showed hypointensity in T1w TSE sequence and hyperintensity both in T1w TSE SPIR and T2w ones with no restriction of the "apparent diffusion coefficient" (ADC). In conclusion, remaining histology the gold standard for the DF diagnosis, imaging features may strongly suggest it.

MDCT arthrography of the wrist: diagnostic accuracy and indications.

PURPOSE: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. MATERIALS AND METHODS: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. RESULTS: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k=0.96) and statistically significant (p<0.05). CONCLUSIONS: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.